@article {287, title = {An abundant ginger compound furanodienone alleviates gut inflammation via the xenobiotic nuclear receptor PXR in mice.}, journal = {Nat Commun}, volume = {16}, year = {2025}, month = {2025 Feb 03}, pages = {1280}, abstract = {

The literature documenting the value of drug-like molecules found in natural products is vast. Although many dietary and herbal remedies have been found to be effective for treating intestinal inflammation, the identification of their active components has lagged behind. In this study, we find that a major ginger component, furanodienone (FDN), is a selective pregnane X receptor (PXR) ligand with agonistic transcriptional outcomes. We show that FDN binds within a sub-pocket of the PXR ligand binding domain (LBD), with subsequent alterations in LBD structure. Using male mice, we show that orally provided FDN has potent PXR-dependant anti-inflammatory outcomes that are colon-specific. Increased affinity and target gene activation in the presence of synergistically acting agonists indicates further opportunities for augmenting FDN activity, efficacy and safety. Collectively, these results support the translational potential of FDN as a therapeutic agent for the treatment and prevention of colonic diseases.

}, keywords = {Animals, Anti-Inflammatory Agents, Colitis, Colon, Furans, Humans, Inflammation, Ligands, Male, Mice, Mice, Inbred C57BL, Pregnane X Receptor, Zingiber officinale}, issn = {2041-1723}, doi = {10.1038/s41467-025-56624-0}, author = {Wang, Xiaojuan and Zhang, Guohui and Bian, Zhiwei and Chow, Vimanda and Grimaldi, Marina and Carivenc, Coralie and Sirounian, Savannah and Li, Hao and Sladekova, Lucia and Mott, Stefano and Luperi, Yulia and Gong, Yufeng and Costello, Cait and Li, Linhao and Jachimowicz, Matthew and Guo, Miao and Hu, Shian and Wilson, Derek and Balaguer, Patrick and Bourguet, William and Mani, Sridhar and Bonati, Laura and Peng, Hui and March, John and Wang, Hongbing and Wang, Shengpeng and Krause, Henry M and Liu, Jiabao} } @article {297, title = {Binding of per- and polyfluoroalkyl substances with liver and serum proteins in rats: implications for physiologically based pharmacokinetic modelling}, journal = {Environment International}, volume = {201}, year = {2025}, author = {Fan, XR and Li, XM and Li, T and Shao, B and Niu, S and Fan, WH and Wang, Q and Zhong, L and Wang, XR and Wang, ZW and Ma, FJ and Zheng GM and Peng, H and Chen, LL and Dong, ZM} } @article {301, title = {Characterizing the metal(loid) contribution to the oxidative potential of thoracic-sized road dust particles.}, journal = {Environ Pollut}, volume = {383}, year = {2025}, month = {2025 Jul 06}, pages = {126785}, abstract = {

To better link airborne PM exposures with toxic endpoints, measurements of oxidative potential (OP) could be an important metric to supplement existing mass-based approaches. The OP of airborne PM has been previously examined elsewhere using acellular chemical assays. The OP of road dust, which is an airborne source of metal(loid)s capable of inducing the generation of reactive oxygen species (ROS), has yet to be characterized. To address existing knowledge gaps, the OP of \< 10\ μm road dust fractions (n\ =\ 27) previously collected in Toronto, Canada, using regenerative-air street sweepers, was measured using the ascorbic acid (AA) and the dithiothreitol (DTT) assays. The lung simulant Gamble{\textquoteright}s solution was used to characterize the OP of total, soluble and insoluble fractions. Stock solutions of V, Cr, Mn, Fe, Ni, Co, Cu, Sb, and Pb were also examined to assess the relative importance of metal(loid)s to OP. To generate an approximate volumetric estimate of the road dust contribution to ambient OP, the mass-based measurements from both chemical assays were modeled using AERMOD. Soluble elemental fractions accounted for 84\ {\textpm}\ 39\% and 65\ {\textpm}\ 26\% of total OP measured using the AA and DTT assays, respectively. Most notably, soluble Cu, Fe, and Mn were found to be primary drivers of OP, estimated to account for 83\ {\textpm}\ 39\% of total OP in the AA assay. These elements amounted to 59\ {\textpm}\ 26\% of total OP using DTT, which is less sensitive to the presence of inorganic constituents. AERMOD modeling revealed that arterial road dust contributed a mean OP of 1.20\ {\textpm}\ 0.41\ nmol/min/m and OP of 1.16\ {\textpm}\ 0.23\ nmol/min/m within 20\ m of the road. The results highlight the importance of road dust in contributing to the potential of airborne PM to induce oxidative stress in the lung.

}, issn = {1873-6424}, doi = {10.1016/j.envpol.2025.126785}, author = {Das, Sourav and Peng, Hui and Wiseman, Clare L S} } @article {298, title = {Enantioselectivity in Metabolism and Toxicity of 6PPD-Quinone in Salmonids}, journal = {Environmental Science and Technology}, volume = {59}, year = {2025}, author = {Li, R and Barrett, H and Nair, P and Wang, MH and Tomlin, H and Atkinson, JB and Krogh, E and Xie, LN and Peng, H} } @article {288, title = {Fast autoxidation of unsaturated lipid films on indoor surfaces.}, journal = {Nat Commun}, volume = {16}, year = {2025}, month = {2025 Feb 12}, pages = {1557}, abstract = {

Organic films containing unsaturated lipids are widespread, yet their oxidation pathways with associated impacts on contaminant lifetimes and human exposure remain poorly explored under indoor environmental conditions. This study demonstrates that UVA radiation and radical exposure drive rapid autoxidation of thin films of methyl linolenate (ML) and canola oil (which contains polyunsaturated triglycerides), primarily producing organic hydroperoxides. For ML films this fast chemistry occurs at the same rate under entirely dark, genuine indoor conditions as it does when the films are exposed to significantly higher OH radicals in a flow reactor. Both OH and organic radicals are detected within the oxidized films, propagating fast autoxidation in dark indoor environments with minimal sensitivity to the radical initiation rate. When mixed into the films, bisphenol A is hydroxylated, illustrating potential transformation pathways for toxic organic contaminants. This study uncovers insights into lipid autoxidation processes under environmental conditions and underscores their potential health impacts.

}, keywords = {Benzhydryl Compounds, Bisphenol A Compounds, Fatty Acids, Monounsaturated, Humans, Hydrogen Peroxide, Linoleic Acids, Oxidation-Reduction, Phenols, Rapeseed Oil, Surface Properties, Ultraviolet Rays}, issn = {2041-1723}, doi = {10.1038/s41467-025-56802-0}, author = {Wang, Xinke and Fahy, William D and Xie, Linna and Peng, Hui and Abbatt, Jonathan P D} } @article {286, title = {Haloacetonitriles Induce Structure-Related Cellular Toxicity Through Distinct Proteome Thiol Reaction Mechanisms.}, journal = {ACS Environ Au}, volume = {5}, year = {2025}, month = {2025 Jan 15}, pages = {101-113}, abstract = {

Haloacetonitriles (HANs) are a class of toxic drinking water disinfection byproducts (DBPs). However, the toxicity mechanisms of HANs remain unclear. We herein investigated the structure-related in vitro toxicity of 6 representative HANs by utilizing complementary bioanalytical approaches. Dibromoacetonitrile (DBAN) displayed strong cytotoxicity and Nrf2 oxidative stress responses, followed by monohalogenated HANs (monoHANs) while other polyhalogenated HANs (polyHANs) exhibited little toxicity. Activity based protein profiling (ABPP) revealed that toxic HANs adduct to human proteome thiols, supporting thiol reactivity as the primary toxicity mechanism for HANs. By using glutathione (GSH) as a thiol surrogate, monoHANs reacted with GSH via S2 while polyHANs reacted through ultrafast addition reactions. In contrast, DBAN generated an unexpected fully debrominated product and glutathione disulfide (GSSG). The unique reaction of DBAN with GSH was found to be mediated by radicals which was supported by electron paramagnetic resonance (EPR) spectroscopy and by radical trapping reagent reaction quenching. Shotgun proteomics further revealed that monoHANs and DBAN adducted to proteome thiols in live cells forming dehalogenated adducts. Multiple antioxidant proteins, SOD1, CSTB, and GAPDH, were adducted by toxic HANs at specific cysteine residues. This study highlights the structurally selective toxicity of HANs in human cells, which are attributed to their distinct reactions with proteome thiols.

}, issn = {2694-2518}, doi = {10.1021/acsenvironau.4c00068}, author = {Yeung, Kirsten and Xie, Linna and Nair, Pranav and Peng, Hui} } @article {294, title = {Increased UV{\textendash}Visible Particle Absorption via Evaporation and Drying of Aqueous Droplets Containing Catechol/HONO Solutions}, journal = {Environmental Science and Technology Letters}, year = {2025}, author = {Wang, Yutong and Yang, Diwen and Fahy, William and Rivellini, Laura-Helena and Peng, Hui and Abbatt, Jonathan} } @article {285, title = {Ligand interaction landscape of transcription factors and essential enzymes in E.~coli.}, journal = {Cell}, year = {2025}, month = {2025 Jan 22}, abstract = {

Knowledge of protein-metabolite interactions can enhance mechanistic understanding and chemical probing of biochemical processes, but the discovery of endogenous ligands remains challenging. Here, we combined rapid affinity purification with precision mass spectrometry and high-resolution molecular docking to precisely map the physical associations of 296 chemically diverse small-molecule metabolite ligands with 69 distinct essential enzymes and 45 transcription factors in the gram-negative bacterium Escherichia coli. We then conducted systematic metabolic pathway integration, pan-microbial evolutionary projections, and independent in-depth biophysical characterization experiments to define the functional significance of ligand interfaces. This effort revealed principles governing functional crosstalk on a network level, divergent patterns of binding pocket conservation, and scaffolds for designing selective chemical probes. This structurally resolved ligand interactome mapping pipeline can be scaled to illuminate the native small-molecule networks of complete cells and potentially entire multi-cellular communities.

}, issn = {1097-4172}, doi = {10.1016/j.cell.2025.01.003}, author = {Peng, Hui and Kotelnikov, Sergei and Egbert, Megan E and Ofaim, Shany and Stevens, Grant C and Phanse, Sadhna and Saccon, Tatiana and Ignatov, Mikhail and Dutta, Shubham and Istace, Zoe and Moutaoufik, Mohamed Taha and Aoki, Hiroyuki and Kewalramani, Neal and Sun, Jianxian and Gong, Yufeng and Padhorny, Dzmitry and Poda, Gennady and Alekseenko, Andrey and Porter, Kathryn A and Jones, George and Rodionova, Irina and Guo, Hongbo and Pogoutse, Oxana and Datta, Suprama and Saier, Milton and Crovella, Mark and Vajda, Sandor and Moreno-Hagelsieb, Gabriel and Parkinson, John and Segre, Daniel and Babu, Mohan and Kozakov, Dima and Emili, Andrew} } @article {291, title = {New Sources of Very Persistent and Very Mobile (vPvM) Substances: A Case Study of the Fluorinated Herbicide Pyroxasulfone.}, journal = {Environ Sci Technol}, year = {2025}, month = {2025 Apr 03}, abstract = {

With the increasing use of fluorinated agrochemicals, more fluorinated compounds enter into the environment. Pyroxasulfone (PYS), a broad-spectrum herbicide containing an aromatic CF (Ar-CF), is expected to grow significantly in application. Although several transformation products (TPs) of PYS have been reported, their distribution and contribution to transformation processes remain largely unknown. This study combined laboratory simulations and a field study. In soil incubation and soil surface photolysis experiments, (5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1-pyrazol-4-yl)methanesulfonic acid (TFPSA) was identified as the main TP of PYS in soil, accounting for over 90\% of all TPs. Field study results showed that PYS and TFPSA were the main species in soil (6.48 {\textpm} 1.82 and 1.54 {\textpm} 0.90 ng g wet weight) and corn plants (2.55 {\textpm} 2.61 and 31.1 {\textpm} 39.6 ng g dry weight in roots) before harvest. Surface water photolysis experiments showed that TFPSA and TP were the major TPs of PYS and no significant photodegradation of TFPSA was observed. Persistent (P) and mobile (M) property assessment indicated TFPSA, TP, and other Ar-CF containing TPs of various fluorinated agrochemicals could be potential very P and very M (vPvM) substances. More attention should be paid to Ar-CF containing agrochemicals and their TPs.

}, issn = {1520-5851}, doi = {10.1021/acs.est.4c13346}, author = {Hou, Xingwang and Gauthier, Jeremy R and Nair, Pranav and Fahy, William D and Peng, Hui and Mabury, Scott A} } @article {292, title = {Quantifying the Effect of Dietary Microplastics on the Potential for Biological Uptake of Environmental Contaminants and Polymer Additives.}, journal = {Environ Sci Technol}, year = {2025}, month = {2025 Apr 22}, abstract = {

The pervasive presence of microplastic in food raises the question of how this presence influences the uptake of organic contaminants from the gastrointestinal tract. Depending on the relative contamination of diet and microplastics, the latter can act either as a vector of contaminants facilitating biological uptake or as a contaminant sink whose sorptive capacity does not diminish during digestion. A comprehensive understanding of these effects ultimately requires the quantification of the effect of microplastics on the thermodynamic driving force responsible for diffusion from the gut lumen to the tissues of an organism. Using silicone-based equilibrium sampling, we quantified the effect of polyvinyl chloride (PVC) microplastics on the fugacity of polychlorinated biphenyls (PCBs) and two polymer additives in dietary and fecal samples of a zoo-housed polar bear. Although PVC microplastics at concentrations well above current observations reduced the fugacities of spiked isotopically labeled PCBs in the polar bear diet and feces slightly, but significantly, leaching from these microplastics greatly elevated fugacities of the additives UV-328 and octabenzone in these samples. The impact of microplastics in the diet on the biological uptake of environmental hydrophobic organic contaminants is likely to be negligible. Microplastics have the potential to be effective vectors for the dietary uptake of polymer additives.

}, issn = {1520-5851}, doi = {10.1021/acs.est.5c02616}, author = {Ng, Desmond and Chen, Yuhao and Lei, Ying Duan and Chen, Wanzhen and Peng, Hui and Gourlie, Sarra and Wania, Frank} } @article {293, title = {A Rapid Testing Kit for 6PPD Screening in Rubber Products.}, journal = {Anal Chem}, year = {2025}, month = {2025 Apr 26}, abstract = {

-(1,3-dimethylbutyl)--phenyl--phenylenediamine (6PPD) has received increasing attention due to its ubiquitous environmental occurrence and extreme aquatic toxicity of its oxidation product 6PPD-quinone. Given 6PPD{\textquoteright}s application as an antioxidant in a wide array of rubber products, cost-effective detection of 6PPD is important for product and waste management. We herein developed a rapid testing kit for the detection (\<10 min) of 6PPD in rubber products with low costs (\<$1/sample), which was inspired by the observation of a red-colored product after 6PPD exposure to oxidants. The selectivity of this reaction was evaluated by 14 structurally diverse phenols and anilines. Interestingly, the protonated -1,3-dimethyl butyl--phenyl quinone diimine (6QDI+H), rather than its neutral or radical counterparts, appeared to be the red-colored product with λ = 490 nm. We further developed a "green" and user-friendly 6PPD rapid testing kit, which was further applied to a wide array of 50 rubber products. 6PPD was detected in 22 out of 50 samples, with a strong agreement ( = 0.896) observed between the results of the rapid testing kit and LC-MS. In summary, this study introduces a 6PPD rapid testing kit for users without requiring expertise in chemistry.

}, issn = {1520-6882}, doi = {10.1021/acs.analchem.5c00079}, author = {Li, Zhuoyuan and Xie, Linna and Nair, Pranav and Yeung, Kirsten and Meek, Oliver and Tao, Juan and Hiki, Kyoshiro and Hao, Chunyan and Peng, Hui} } @article {295, title = {Semiquantitative Nontargeted Screening of Organophosphorus Plastic Additives in Consumer Products Using P NMR.}, journal = {Environ Sci Technol}, year = {2025}, month = {2025 Jun 02}, abstract = {

Mass spectrometry (MS) is typically employed for the nontargeted identification of unknown organophosphorus compounds (OPCs). However, quantitative analysis remains a major challenge due to the lack of authentic standards for most of the OPCs. A phosphorus NMR (P NMR) method for semiquantitative nontargeted analysis was developed and applied to 37 different plastic products, where OPCs were detected in nine at high concentrations (86.9-7206 nmol/g). Three classes of compounds were detected with clearly separated chemical shifts, including organophosphites (δ = 125-140 ppm) and organophosphates (δ = (-20)-5 ppm), as well as an unexpected "unannotated" class (δ = 5-20 ppm). The "unannotated" class was subsequently identified as organophosphite diesters and confirmed through in-lab hydrolysis trials. In this work, we demonstrate how a P NMR method may serve as a powerful analytical tool when combined with mass spectrometry for the nontargeted analysis of OPCs. We highlight organophosphite diesters as a novel class of compounds which represent a potential source of organophosphate diesters in the environment.

}, issn = {1520-5851}, doi = {10.1021/acs.est.5c02789}, author = {Chen, Wanzhen and Miller, Jolie M and Burns, Darcy C and Almuhtaram, Husein and Andrews, Robert C and Peng, Hui} } @article {289, title = {Structure and Toxicity Characterization of Alkyl Hydroxylated Metabolites of 6PPD-Q.}, journal = {Environ Sci Technol}, year = {2025}, month = {2025 Apr 08}, abstract = {

Distinct from other nontoxic phenyl--phenylenediamine (PPD) quinones, -(1,3-dimethylbutyl)-{\textquoteright}-phenyl--phenylenediamine-quinone (6PPD-Q) was recently discovered to be regioselectively metabolized to alkyl hydroxylated metabolites (alkyl-OH-6PPD-Q) in rainbow trout. It remains unknown whether the unique alkyl-OH-6PPD-Q contributes to the toxicity of 6PPD-Q. To test this, we herein synthesized chemical standards of alkyl-OH-6PPD-Q isomers and investigated their metabolic formation mechanism and toxicity. The predominant alkyl-OH-6PPD-Q was confirmed to be hydroxylated on the C tertiary carbon (C-OH-6PPD-Q). The formation of C-OH-6PPD-Q was only observed in microsomal but not in cytosolic fractions of rainbow trout () liver S9. A general cytochrome P450 (CYP450) inhibitor fluoxetine inhibited the formation of hydroxylated metabolites of 6PPD-Q, supporting that CYP450 catalyzed the hydroxylation. This well-explained the compound- and regio-selective formation of C-OH-6PPD-Q, due to the weak C-H bond on the C tertiary carbon. Surprisingly, while cytotoxicity was observed for 6PPD-Q and C-OH-6PPD-Q in a coho salmon () embryo (CSE-119) cell line, no toxicity was observed for C-OH-6PPD-Q. To further confirm this under physiologically relevant conditions, we fractionated 6PPD-Q metabolites formed in the liver microsome of rainbow trout. Cytotoxicity was observed for the fraction of 6PPD-Q, but not the fraction of C-OH-6PPD-Q. In summary, this study highlighted the C tertiary carbon as the key moiety for both metabolism and toxicity of 6PPD-Q and confirmed that alkyl hydroxylation is a detoxification pathway for 6PPD-Q.

}, issn = {1520-5851}, doi = {10.1021/acs.est.4c11823}, author = {Nair, Pranav and Barrett, Holly and Tanoto, Kaylin and Xie, Linna and Sun, Jianxian and Yang, Diwen and Yao, Han and Song, Datong and Peng, Hui} } @article {290, title = {Synthesis and Toxicity Evaluation of -Phenylenediamine-Quinones.}, journal = {Environ Sci Technol}, year = {2025}, month = {2025 Apr 08}, abstract = {

-(1,3-Dimethylbutyl)--phenyl--phenylenediamine-quinone (6PPD-Q), the tire rubber-derived transformation product of 6PPD, was recently discovered to cause the acute mortality of coho salmon (). Aiming to identify potential replacement antiozonants for 6PPD that do not produce toxic quinones, seven PPD-quinones with distinct side chains were synthesized to investigate their structure-related toxicities using rainbow trout (). While 6PPD-Q exerted high toxicity (96 h LC = 0.35 μg/L), toxicity was not observed for six other PPD-quinones despite their similar structures. The fish tissue concentrations of 6PPD-Q after sublethal exposure (0.29 μg/L) were comparable to the other PPD-quinones, which indicated that bioaccumulation levels were not the reason for the selective toxicity of 6PPD-Q. Hydroxylated PPD-quinones were detected as the predominant metabolites in fish tissue. Interestingly, a single major aromatic hydroxylation metabolite was detected for the alternate PPD-quinones, but two abundant OH-6PPD-Q isomers were detected for 6PPD-Q. MS spectra confirmed that hydroxylation occurred on the alkyl side chain for one isomer. The structurally selective toxicity of 6PPD-Q was also observed in a coho salmon (CSE-119) cell line, which further supports its intrinsic toxicity. This study reported the selective toxicity of 6PPD-Q and pinpointed the possibility for other PPDs to be applied as potential substitutes of 6PPD.

}, issn = {1520-5851}, doi = {10.1021/acs.est.4c12220}, author = {Nair, Pranav and Sun, Jianxian and Xie, Linna and Kennedy, Lisa and Kozakiewicz, Derek and Kleywegt, Sonya M and Hao, Chunyan and Byun, Hannah and Barrett, Holly and Baker, Joshua and Monaghan, Joseph and Krogh, Erik T and Song, Datong and Peng, Hui} } @article {277, title = {Compound Class-Specific Temporal Trends (2021{\textendash}2023) of Tire Wear Compounds in Suspended Solids from Toronto Wastewater Treatment Plants}, journal = {ACS ES\&T Water}, year = {2024}, month = {11/2024}, author = {Xie, Linna and Yuan, Lai and Sun, Jianxian and Yang, Miqing and Khan, Ismail and Lopez, Joselyn and Gong, Yufeng and Nair, Pranav and Hao, Chunyan and Helm, Paul and Barrett, Holly and Edwards, Elizabeth and Peng, Hui} } @article {263, title = {Diindoles produced from commensal microbiota metabolites function as endogenous CAR/Nr1i3 ligands}, journal = {Nature Communications}, year = {2024}, author = {Liu, Jiabao and Malekoltojari, Aniaz and Asokakumar, Anjana and Chow, Vimanda and Li, Linhao and Li, Hao and Grimaldi, Marina and Dang, Nathanlown and Campbell, Jhenielle and Barrett, Holly and Sun, Jianxian and Navarre, William and Wilson, Derek and Wang, Hongbing and Mani, Sridhar and Balaguer, Patrick and Anakk, Sayeepriyadarshini and Peng, Hui* and Krause, Henry*} } @article {275, title = {Emerging investigator series: nontargeted screening of aryl hydrocarbon receptor agonists in endangered beluga whales from the St. Lawrence Estuary: beyond legacy contaminants.}, journal = {Environ Sci Process Impacts}, volume = {26}, year = {2024}, month = {2024 Sep 18}, pages = {1451-1464}, abstract = {

The elevated concentrations of organohalogen contaminants in the endangered St. Lawrence Estuary (SLE) belugas have prompted the hypothesis that aryl hydrocarbon receptor (AhR) activity may be a contributor towards their potential adverse effects. While indirect associations between AhR and contaminant levels have been reported in SLE beluga tissues, AhR activity was never directly measured. Using bioassays and nontargeted analysis, this study contrasted AhR activity and agonist profiles between pooled tissue extracts of endangered SLE and non-threatened Arctic belugas. Tissue extracts of SLE belugas exhibited significantly higher overall AhR activity than that of Arctic belugas, with a 2000s SLE beluga liver extract exerting significantly higher activity than blubber extracts of SLE and Arctic belugas from the same time period. Contrary to our expectations, well-known AhR agonists detected by nontargeted analysis, including polychlorinated biphenyls (PCBs), were only minor contributors to the observed AhR activity. Instead, Tox21 suspect screening identified more polar chemicals, such as dyes and natural indoles, as potential contributors. Notably, the natural product bromoindole was selectively detected in SLE beluga liver at high abundance and was further confirmed as an AhR agonist. These findings highlighted the significance of the AhR-mediated toxicity pathway in belugas and underscored the importance of novel AhR agonists, particularly polar compounds, in its induction.

}, keywords = {Animals, Beluga Whale, Endangered Species, Environmental Monitoring, Estuaries, Liver, Polychlorinated Biphenyls, Receptors, Aryl Hydrocarbon, Water Pollutants, Chemical}, issn = {2050-7895}, doi = {10.1039/d4em00243a}, author = {Barrett, Holly and Sun, Jianxian and Chen, Yuhao and Yang, Diwen and Verreault, Jonathan and Houde, Magali and Wania, Frank and Peng, Hui} } @article {273, title = {Hydroxyl radical oxidation of chemical contaminants on indoor surfaces and dust.}, journal = {Proc Natl Acad Sci U S A}, volume = {121}, year = {2024}, month = {2024 Nov 05}, pages = {e2414762121}, abstract = {

Humans are widely exposed to semivolatile organic contaminants in indoor environments. Many contaminants have long lifetimes following partitioning to the large surface reservoirs present indoors, which leads to long exposure times to gas-phase oxidants and multiphase chemistry. Studies have shown selective multiphase oxidation of organics on indoor surfaces, but the presence of hydroxyl radicals with nonselective reactivity and evidence of multiphase OH radical reactivity toward common indoor contaminants indicates that there may be additional unknown transformation chemistry indoors. We screened genuine indoor samples for 60 OH radical oxidation products of the common plasticizer and endocrine-disrupting contaminant bis(2-ethylhexyl) phthalate (DEHP) identified in laboratory experiments using nontargeted high-resolution mass spectrometry. At least 30 and 10 of these products are observed in indoor dust and DEHP films exposed to ambient indoor conditions, respectively, indicating that multiphase OH reactions occur indoors. Using the PROTEX model and a multimedia indoor chemical fate model, we demonstrate that these products have long indoor lifetimes and cause a higher potential for human exposure than DEHP. Some of these products are more active endocrine disruptors than DEHP itself, but most have unknown toxicities. Coexposure to all oxidation products will likely have an additive effect, leading to higher human health risks from indoor organic contaminants than previously thought. Due to the nonselective reactivity of OH radicals, it is likely that most indoor contaminants follow similar chemistry, and further study is needed to understand the prevalence and human health implications of such multiphase chemistry.

}, issn = {1091-6490}, doi = {10.1073/pnas.2414762121}, author = {Fahy, William D and Gong, Yufeng and Wang, Shenghong and Zhang, Zhizhen and Li, Li and Peng, Hui and Abbatt, Jonathan P D} } @article {269, title = {Identification of environmental and methodological factors driving variability of Pepper Mild Mottle Virus (PMMoV) across three wastewater treatment plants in the City of Toronto.}, journal = {Sci Total Environ}, volume = {932}, year = {2024}, month = {2024 Jul 01}, pages = {172917}, abstract = {

PMMoV has been widely used to normalize the concentration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, influenza, and respiratory syncytial virus (RSV) to account for variations in the fecal content of wastewater. PMMoV is also used as an internal RNA recovery control for wastewater-based epidemiology (WBE) tests. While potentially useful for the interpretation of WBE data, previous studies have suggested that PMMoV concentration can be affected by various physico-chemical characteristics of wastewater. There is also the possibility that laboratory methods, particularly the variability in centrifugation steps to remove supernatant from pellets can cause PMMoV variability. The goal of this study is to improve our understanding of the main drivers of PMMoV variability by assessing the relationship between PMMoV concentration, the physico-chemical characteristics of wastewater, and the methodological approach for concentrating wastewater samples. We analyzed 24-hour composite wastewater samples collected from the influent stream of three wastewater treatment plants (WWTPs) located in the City of Toronto, Ontario, Canada. Samples were collected 3 to 5 times per week starting from the beginning of March 2021 to mid-July 2023. The influent flow rate was used to partition the data into wet and dry weather conditions. Physico-chemical characteristics (e.g., total suspended solids (TSS), biological oxygen demand (BOD), alkalinity, electrical conductivity (EC), and ammonia (NH)) of the raw wastewater were measured, and PMMoV was quantified. Spatial and temporal variability of PMMoV was observed throughout the study period. PMMoV concentration was significantly higher during dry weather conditions. Multiple linear regression analysis demonstrates that the number and type of physico-chemical parameters that drive PMMoV variability are site-specific, but overall BOD and alkalinity were the most important predictors. Differences in PMMoV concentration for a single WWTP between two different laboratory methods, along with a weak correlation between pellet mass and TSS using one method may indicate that differences in sample concentration and subjective subsampling bias could alter viral recovery and introduce variability to the data.

}, keywords = {Environmental Monitoring, Ontario, Tobamovirus, Waste Disposal, Fluid, Wastewater}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2024.172917}, author = {Goitom, Eyerusalem and Ariano, Sarah and Gilbride, Kim and Yang, Minqing Ivy and Edwards, Elizabeth A and Peng, Hui and Dannah, Nora and Farahbakhsh, Farnaz and Hataley, Eden and Sarvi, Hooman and Sun, Jianxian and Waseem, Hassan and Oswald, Claire} } @article {271, title = {Identification of Hydrocarbon Sulfonates as Previously Overlooked Transthyretin Ligands in the Environment.}, journal = {Environ Sci Technol}, year = {2024}, month = {2024 May 30}, abstract = {

Incidences of thyroid disease, which has long been hypothesized to be partially caused by exposure to thyroid hormone disrupting chemicals (TDCs), have rapidly increased in recent years. However, known TDCs can only explain a small portion (\~{}1\%) of human transthyretin (hTTR) binding activities in environmental samples, indicating the existence of unknown hTTR ligands. In this study, we aimed to identify the major environmental hTTR ligands by employing protein ffinity urification with ontargeted nalysis (APNA). hTTR binding activities were detected in all 11 indoor dust and 9 out of 10 sewage sludge samples by the FITC-T displacement assay. By using APNA, 31 putative hTTR ligands were detected including perfluorooctanesulfonate (PFOS). Two of the most abundant ligands were identified as hydrocarbon surfactants ( dodecyl benzenesulfonate). Moreover, another abundant ligand was surprisingly identified as a disulfonate fluorescent brightener, 4,4{\textquoteright}-bis(2-sulfostyryl)biphenyl sodium (CBS). CBS was validated as a nM-affinity hTTR ligand with an IC of 345 nM. In total, hydrocarbon surfactants and fluorescent brighteners explain 1.92-17.0 and 5.74-54.3\% of hTTR binding activities in dust and sludge samples, respectively, whereas PFOS only contributed \<0.0001\%. Our study revealed for the first time that hydrocarbon sulfonates are previously overlooked hTTR ligands in the environment.

}, issn = {1520-5851}, doi = {10.1021/acs.est.3c10973}, author = {Gong, Yufeng and Sun, Jianxian and Wang, Xiaoyun and Barrett, Holly and Peng, Hui} } @article {260, title = {Light Exposure of Wood Smoke Aerosol: Connecting Optical Properties, Oxidation, Radical Formation, and Chemical Composition}, journal = {ACS ES\&T Air}, volume = {1}, year = {2024}, author = {Liu-Kang, Carolyn and Sokolova, Anna and Gong, Yufeng and Fahy, William D and Peng, Hui and Abbatt, Jonathan PD} } @article {274, title = {Multigenerational effects of disperse blue 79 at environmentally relevant concentrations on zebrafish (Danio rerio) fecundity: An integrated approach.}, journal = {J Hazard Mater}, volume = {478}, year = {2024}, month = {2024 Oct 05}, pages = {135442}, abstract = {

The brominated azo dye (BAD) Disperse Blue (DB79) is a widespread environmental pollutant. The long-term toxicological effects of DB79 and the mechanisms thereof must be understood to allow assessment of the risks of DB79 pollution. A dual-omics approach employing in silico analysis, bioinformatics, and in vitro bioassays was used to investigate the transgenerational (F-F) toxicity of DB79 in zebrafish at environmentally relevant concentrations and identify molecular initiating events and key events associated with DB79-induced fertility disorders. Exposure to 500\ {\textmu}g/L DB79 decreased fecundity in the F and F generations by \>\ 30\ \% and increased the condition factor of the F generation 1.24-fold. PPARα/RXR and PXR ligand binding activation were found to be critical molecular initiating events associated with the decrease in fecundity. Several key events (changes in fatty acid oxidation and uptake, lipoprotein metabolism, and xenobiotic metabolism and transport) involved in lipid dysregulation and xenobiotic disposition were found to be induced by DB79 through bioinformatic annotation using dual-omics data. The biomolecular underpinnings of decreased transgenerational fertility in zebrafish attributable to BAD exposure were elucidated and novel biomolecular targets in the adverse outcome pathway framework were identified. These results will inform future studies and facilitate the development of mitigation strategies.

}, keywords = {Animals, Azo Compounds, Female, Fertility, Male, Pregnane X Receptor, Water Pollutants, Chemical, Zebrafish}, issn = {1873-3336}, doi = {10.1016/j.jhazmat.2024.135442}, author = {Wang, Chao and Gu, Wen and Zhang, Shaoping and Li, Li and Kong, Jian and Zhi, Hong and Liu, Juan and Wang, Mengmeng and Miao, Ke and Li, Qi and Yu, Jie and Wang, Runming and He, Runming and Zhang, Shuyi and Deng, Fuchang and Duan, Shuling and Zhang, Qiannan and Liu, Zhenming and Yang, Hui and Jia, Xudong and Peng, Hui and Tang, Song} } @article {254, title = {Multiphase Ozonolysis of Bisphenol A: Chemical Transformations on Surfaces in the Environment.}, journal = {Environ Sci Technol}, year = {2024}, month = {2024 Feb 13}, abstract = {

High global plastic production volumes have led to the widespread presence of bisphenol compounds in human living and working environments. The most common bisphenol, bisphenol A (BPA), despite being endocrine disruptive and estrogenic, is still not fully banned worldwide, leading to continued human exposure via particles in air, dust, and surfaces in both outdoor and indoor environments. While its abundance is well documented, few studies have addressed the chemical transformations of BPA, the properties of its reactive products, and their toxicity. Here, the first gas-surface multiphase ozonolysis experiment of BPA thin films, at a constant ozone mixing ratio of 100 ppb, was performed in a flow tube for periods up to 24 h. Three transformation products involving the addition of 1, 2, and 3 oxygen atoms to the molecule were identified by LC-ESI-HRMS analyses. Exposure of indoor air to thin BPA surface films and BPA-containing thermal paper over periods of days validated the flow tube experiments, demonstrating the rapid nature of this multiphase ozonolysis reaction at atmospherically relevant ozone levels. Multiple transformation pathways are proposed that are likely applicable to not only BPA but also emerging commercial bisphenol products.

}, issn = {1520-5851}, doi = {10.1021/acs.est.3c08932}, author = {Yu, Jie and Gong, Yufeng and Nair, Pranav and Liggio, John and Peng, Hui* and Abbatt, Jonathan P D*} } @article {276, title = {Structurally Selective Ozonolysis of -Phenylenediamines and Toxicity in Coho Salmon and Rainbow Trout.}, journal = {Environ Sci Technol}, year = {2024}, month = {2024 Nov 23}, abstract = {

The tire-rubber-derived ozonation product of -(1,3-dimethylbutyl)-{\textquoteright}-phenyl--phenylenediamine (6PPD), -(1,3-dimethylbutyl)-{\textquoteright}-phenyl--phenylenediamine-quinone (6PPD-Q), was recently discovered to cause acute mortality in coho salmon (). -Phenylenediamines (PPDs) with variable side chains distinct from 6PPD have been identified as potential replacement antioxidants, but their toxicities remain unclear under environmentally relevant ozone conditions. We herein tested the multiphase gas-surface ozone reactivity of four select PPDs [6PPD, -isopropyl-{\textquoteright}-phenyl--phenylenediamine (IPPD), ,{\textquoteright}-diphenyl--phenylenediamine (DPPD), and -phenyl-{\textquoteright}-cyclohexyl--phenylenediamine (CPPD)] and evaluated the toxicity of their reaction mixtures in coho salmon, rainbow trout (), and fathead minnow (). 6PPD and IPPD were found to rapidly react with ozone, while no significant multiphase ozone reactivity was observed for DPPD or CPPD. The viability of coho salmon CSE-119 cells was strongly affected by the ozonolysis products of 6PPD but not by those of the other three PPDs. Acute mortality was only observed in juvenile rainbow trout that were exposed to oxidized 6PPD, suggesting a common mechanism of toxic action in the two salmonid fish species. This study reports the structurally selective ozone reactivity of PPDs and the unique toxicity of 6PPD ozonolysis mixtures, which demonstrates that other PPDs are potential alternative antioxidants.

}, issn = {1520-5851}, doi = {10.1021/acs.est.4c04817}, author = {Xie, Linna and Yu, Jie and Nair, Pranav and Sun, Jianxian and Barrett, Holly and Meek, Oliver and Qian, Xing and Yang, Diwen and Kennedy, Lisa and Kozakiewicz, Derek and Hao, Chunyan and Hansen, John D and Greer, Justin B and Abbatt, Jonathan P D and Peng, Hui} } @article {270, title = {Underestimation of SARS-CoV-2 in wastewater due to single or double mutations in the N1 qPCR probe binding region.}, journal = {Water Res X}, volume = {22}, year = {2024}, month = {2024 Jan 01}, pages = {100221}, abstract = {

Wastewater surveillance using RT-qPCR has now been widely adopted to track circulating levels of SARS-CoV-2 virus in many sewersheds. The CDC qPCR assays targeting two regions (N1 and N2) within the N gene are commonly used, but a discrepancy between the two biomarkers has been noticed by independent studies using these methods since late 2021. The reason is presumed to be due to mutations in regions targeted by the N1 qPCR probe. In this study, we systematically investigated and unequivocally confirmed that the underlying reason for this discrepancy was mutations in the N1 probe target, and that a single mutation could cause a significant drop in signal. We first confirmed the proportion of related mutations in wastewater samples (Jan 2021-Dec 2022) using nested PCR and LC-MS. Based on relative proportions of N1 alleles, we separated the wastewater data into four time periods corresponding to different variant waves: Period I (Alpha and Delta waves with 0 mutation), Period II (BA.1/BA.2 waves with a single mutation found in all Omicron strains), Period III (BA.5.2* wave with two mutations), and Period IV (BQ.1* wave with two mutations). Significantly lower N1 copies relative to N2 copies in samples from Periods II-IV compared to those from Period I was observed in wastewater. To further pinpoint the extent to which each mutation impacted N1 quantification, we compared the qPCR response among different synthetic oligomers with corresponding mutations. This study highlighted the impact of even just one or two mutations on qPCR-based wastewater surveillance of SARS-CoV-2.

}, issn = {2589-9147}, doi = {10.1016/j.wroa.2024.100221}, author = {Sun, Jianxian and Yang, Minqing Ivy and Peng, Jiaxi and Khan, Ismail and Lopez, Jhoselyn Jaramillo and Chan, Ronny and Edwards, Elizabeth A and Peng, Hui} } @article {268, title = {Unique hepatic maternal transfer pattern of trace metals and perfluoroalkyl substances (PFAS) in a bluntnose sixgill shark (Hexanchus griseus).}, journal = {Chemosphere}, volume = {359}, year = {2024}, month = {2024 May 10}, pages = {142315}, abstract = {

The fate and distribution of environmental contaminants includes bioaccumulation within marine organisms. A deceased 4-m long adult female bluntnose sixgill shark, pregnant with 72 pups, was recovered from Coles Bay on Vancouver Island, BC, Canada in 2019. This specimen provided a unique opportunity to examine maternal transfer of contaminants in a yolk-sac viviparous shark species. Liver subsamples of the adult and offspring were analyzed for 18 targeted inorganic elements by inductively coupled plasma optical emission spectroscopy (ICP-OES) and 21 targeted perfluoroalkyl substances (PFAS) by liquid chromatography-electrospray ionization-high resolution mass spectrometry (LC-ESI-Orbitrap MS). The maternal-offspring transfer efficiencies in liver tissue were subsequently examined for both contaminant classes. Concentrations of all detectable metals apart from calcium and magnesium were found to be higher in the mother compared to the offspring, including substantial levels of toxic cadmium (6\ {\textpm}\ 2\ mg\ kg dw) and lead (7\ {\textpm}\ 3\ mg\ kg dw). Conversely, high maternal transfer efficiencies were observed for PFAS (i.e., ΣPFAS\ =\ 71\ {\textpm}\ 9\ ng\ g ww in offspring compared to 13\ {\textpm}\ 9\ ng\ g ww in the mother). This study highlighted the unique maternal transfer characteristics of PFAS in bluntnose sixgill sharks depending on the structure of the polar head group, with greater liver-to-liver transfer efficiencies observed for perfluorocarboxylic acids (PFCAs) than perfluorosulfonic acids (PFSAs) of the same fluorocarbon chain length.

}, issn = {1879-1298}, doi = {10.1016/j.chemosphere.2024.142315}, author = {Zvekic, Misha and Barrett, Holly and Diamente, Peter and Peng, Hui and Krogh, Erik T} } @article {227, title = {All-in-one digital microfluidics pipeline for proteomic sample preparation and analysis}, journal = {Chemical Science}, year = {2023}, chapter = {in press}, author = {Peng, JX and Chan, C and Zhang, SL and Sklavounos, AA and Olson, ME and Scott, EY and Hu, YC and Rajesh, V and LI, BB and Chamberlain, MD and Zhang, S and Peng, H and Wheeler, AR} } @article {225, title = {Building the Environmental Chemical-Protein Interaction Network (eCPIN): An Exposome-Wide Strategy for Bioactive Chemical Contaminant Identification}, journal = {Environmental Science and Technology}, year = {2023}, chapter = {in press}, author = {Gong, YF and Yang, DW and Barrett, H and Yang, DW and Peng, H} } @article {221, title = {Declining concentrations of chlorinated paraffins in endangered St. Lawrence Estuary belugas (Delphinapterus leucas): Response to regulations or a change in diet?}, journal = {Sci Total Environ}, year = {2023}, month = {2023 Jan 07}, pages = {161488}, abstract = {

Very high levels of industrial contaminants in St. Lawrence Estuary (SLE) beluga whales represent one of the major threats to this population classified as endangered under the Species at Risk Act in Canada. Elevated concentrations of short-chained chlorinated paraffins (SCCPs) were recently reported in blubber of adult male SLE belugas. Recent regulations for SCCPs in North America, combined with their replacement by medium- (MCCPs) and long-chained chlorinated paraffins (LCCPs), highlight the importance of tracking this toxic chemical class. The objectives of this study were to evaluate (1) levels and profiles of chlorinated paraffins (CPs) in samples obtained from carcasses of adult male, adult female, juvenile, newborn, and fetus beluga, and (2) trends in adult male belugas between 1997 and 2018. Factors potentially influencing CP temporal trends such as age, feeding ecology and sampling year were also explored. SCCPs dominated (64 to 100 \%) total CP concentrations across all age and sex classes, MCCPs accounted for the remaining proportion of total CPs, and LCCPs were not detected in any sample. The chlorinated paraffin homolog that dominated the most in beluga blubber was CCl. Adult male SCCP concentrations from this study were considerably lower (\> 2000-fold) than those recently reported in Simond et al. (2020), likely reflecting a previously erroneous overestimate due to the lack of a suitable analytical method for SCCPs at the time. Both SCCPs and total CPs declined over time in adult males in our study (rate of 1.67 and 1.33 \% per year, respectively), presumably due in part to the implementation of regulations in 2012. However, there is a need to better understand the possible contribution of a changing diet to contaminant exposure, as stable isotopic ratios of carbon also changed over time.

}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2023.161488}, author = {Simond, Antoine {\'E} and Ross, Peter S and Cabrol, Jory and Lesage, V{\'e}ronique and Lair, St{\'e}phane and Woudneh, Million B and Yang, Diwen and Peng, Hui and Colbourne, Katerina and Brown, Tanya M} } @article {237, title = {Disclosing Environmental Ligands of L-FABP and PPARγ: Should We Re-evaluate the Chemical Safety of Hydrocarbon Surfactants?}, journal = {Environ Sci Technol}, year = {2023}, month = {2023 Aug 01}, abstract = {

Chemical contaminants can cause adverse effects by binding to the liver-fatty acid binding protein (L-FABP) and peroxisome proliferator-activated nuclear receptor γ (PPARγ), which are vital in lipid metabolism. However, the presence of numerous compounds in the environment has hindered the identification of their ligands, and thus only a small portion have been discovered to date. In this study, protein ffinity urification with ontargeted nalysis (APNA) was employed to identify the ligands of L-FABP and PPARγ in indoor dust and sewage sludge. A total of 83 nonredundant features were pulled-out by His-tagged L-FABP as putative ligands, among which 13 were assigned as fatty acids and hydrocarbon surfactants. In contrast, only six features were isolated when His-tagged PPARγ LBD was used as the protein bait. The binding of hydrocarbon surfactants to L-FABP and PPARγ was confirmed using both recombinant proteins and reporter cells. These hydrocarbon surfactants, along with \>50 homologues and isomers, were detected in dust and sludge at high concentrations. Fatty acids and hydrocarbon surfactants explained the majority of L-FABP (57.7 {\textpm} 32.9\%) and PPARγ (66.0 {\textpm} 27.1\%) activities in the sludge. This study revealed hydrocarbon surfactants as the predominant synthetic ligands of L-FABP and PPARγ, highlighting the importance of re-evaluating their chemical safety.

}, issn = {1520-5851}, doi = {10.1021/acs.est.3c02898}, author = {Gong, Yufeng and Yang, Diwen and Liu, Jiabao and Barrett, Holly and Sun, Jianxian and Peng, Hui} } @article {222, title = {Dynamic Wood Smoke Aerosol Toxicity during Oxidative Atmospheric Aging.}, journal = {Environ Sci Technol}, year = {2023}, month = {2023 Jan 11}, abstract = {

Wildfires are a major source of biomass burning aerosol to the atmosphere, with their incidence and intensity expected to increase in a warmer future climate. However, the toxicity evolution of biomass burning organic aerosol (BBOA) during atmospheric aging remains poorly understood. In this study, we report a unique set of chemical and toxicological metrics of BBOA from pine wood smoldering during multiphase aging by gas-phase hydroxyl radicals (OH). Both the fresh and OH-aged BBOA show activity relevant to adverse health outcomes. The results from two acellular assays (DTT and DCFH) show significant oxidative potential (OP) and reactive oxygen species (ROS) formation in OH-aged BBOA. Also, radical concentrations in the aerosol assessed by electron paramagnetic resonance (EPR) spectroscopy increased by 50\% following heterogeneous aging. This enhancement was accompanied by a transition from predominantly carbon-centered radicals (85\%) in the fresh aerosol to predominantly oxygen-centered radicals (76\%) following aging. Both the fresh and aged biomass burning aerosols trigger prominent antioxidant defense during the exposure, indicating the induction of oxidative stress by BBOA in the atmosphere. By connecting chemical composition and toxicity using an integrated approach, we show that short-term aging initiated by OH radicals can produce biomass burning particles with a higher particle-bound ROS generation capacity, which are therefore a more relevant exposure hazard for residents in large population centers close to wildfire regions than previously studied fresh biomass burning emissions.

}, issn = {1520-5851}, doi = {10.1021/acs.est.2c05929}, author = {Wang, Shunyao and Gallimore, Peter J and Liu-Kang, Carolyn and Yeung, Kirsten and Campbell, Steven J and Utinger, Battist and Liu, Tengyu and Peng, Hui and Kalberer, Markus and Chan, Arthur W H and Abbatt, Jonathan P D} } @article {236, title = {Effects of Triclosan on the Development of Antimicrobial Resistance in the Environment: A Review}, journal = {Current Pollution Report}, year = {2023}, author = {Zhang, CZ and Liu, SH and Feng, HD and Barrett, H and Karunaratne, SHP and Zhang, Y and Yang, M} } @article {231, title = {Leaching of dibutyltin dichloride from virgin polyvinyl chloride (PVC) pipe material}, journal = {ACS ES\&T Water}, year = {2023}, month = {In press}, author = {Wu, MH and Chen, WZ and Peng, H and Almuhtaram H and Andrews RC} } @article {235, title = {Multi-omics reveals 2-bromo-4,6-dinitroaniline (BDNA)-induced hepatotoxicity and the role of the gut-liver axis in rats.}, journal = {J Hazard Mater}, volume = {457}, year = {2023}, month = {2023 Jun 03}, pages = {131760}, abstract = {

2-Bromo-4, 6-dinitroaniline (BDNA) is a widespread azo-dye-related hazardous pollutant. However, its reported adverse effects are limited to mutagenicity, genotoxicity, endocrine disruption, and reproductive toxicity. We systematically assessed the hepatotoxicity of BDNA exposure via pathological and biochemical examinations and explored the underlying mechanisms via integrative multi-omics analyses of the transcriptome, metabolome, and microbiome in rats. After 28 days of oral administration, compared with the control group, 100\ mg/kg BDNA significantly triggered hepatotoxicity, upregulated toxicity indicators (e.g., HSI, ALT, and ARG1), and induced systemic inflammation (e.g., G-CSF, MIP-2, RANTES, and VEGF), dyslipidemia (e.g., TC and TG), and bile acid (BA) synthesis (e.g., CA, GCA, and GDCA). Transcriptomic and metabolomic analyses revealed broad perturbations in gene transcripts and metabolites involved in the representative pathways of liver inflammation (e.g., Hmox1, Spi1, L-methionine, valproic acid, and choline), steatosis (e.g., Nr0b2, Cyp1a1, Cyp1a2, Dusp1, Plin3, arachidonic acid, linoleic acid, and palmitic acid), and cholestasis (e.g., FXR/Nr1h4, Cdkn1a, Cyp7a1, and bilirubin). Microbiome analysis revealed reduced relative abundances of beneficial gut microbial taxa (e.g., Ruminococcaceae and Akkermansia muciniphila), which further contributed to the inflammatory response, lipid accumulation, and BA synthesis in the enterohepatic circulation. The observed effect concentrations here were comparable to the highly contaminated wastewaters, showcasing BDNA{\textquoteright}s hepatotoxic effects at environmentally relevant concentrations. These results shed light on the biomolecular mechanism and important role of the gut-liver axis underpinning BDNA-induced cholestatic liver disorders in vivo.

}, issn = {1873-3336}, doi = {10.1016/j.jhazmat.2023.131760}, author = {Deng, Fuchang and Qin, Guangqiu and Chen, Yuanyuan and Zhang, Xu and Zhu, Mu and Hou, Min and Yao, Qiao and Gu, Wen and Wang, Chao and Yang, Hui and Jia, Xudong and Wu, Chongming and Peng, Hui and Du, Huamao and Tang, Song} } @article {228, title = {Per- and Polyfluoroalkyl Substances in Canadian Fast Food Packaging}, journal = {Environ. Sci. Technol. Lett}, year = {2023}, author = {Schwartz-Narbonne, Heather and Xia, CJ and Shalin, A and Whitehead, HD and Yang, DW and Peaslee, Graham F and Wang, ZY and Wu, Y and Peng, H and Blum, A and Venier, M and Diamond, ML} } @article {232, title = {PPARg as a potential target for adipogenesis induced by fine particulate matter in 3T3-L1 preadipocytes}, journal = {Environmental Science and Technology}, year = {2023}, chapter = {in press}, author = {Cao, YQ and Chen, YY and Miao, K and Zhang, SY and Deng, FC and Zhu, M and Wang, C and Gu, W and Huang, YX and Shao, ZJ and Dong, XY and Gong YF and Peng, H and Yang, H and Wan, Y and Jia, XD and Tang, S} } @article {244, title = {Prioritizing molecular formulae identified by non-target analysis through high-throughput modelling: application to identify compounds with high human accumulation potential from house dust.}, journal = {Environ Sci Process Impacts}, year = {2023}, month = {2023 Oct 16}, abstract = {

Because it is typically not possible to pursue compound identification efforts for all chemical features detected during non-target analysis (NTA), the need for prioritization arises. Here we propose a strategy that ranks chemical features detected in environmental samples based on a model-derived metric that quantifies a feature{\textquoteright}s attribute that makes it desirable to elucidate its structure, , a high potential for bioaccumulation in humans or wildlife. The procedure involves the identification of isomers that could plausibly represent the molecular formulae assigned to NTA-detected chemical features. For each isomer, the prioritization metric is calculated using properties predicted with high-throughput methods. After the molecular formulae are ranked based on the average values of the prioritization metric calculated for all isomers assigned to a formula, the highest ranked molecular formulae are prioritized for structure elucidation. We applied this workflow to features identified in house dust, using the ratio of chemical intake through dust ingestion to chemical concentration in blood (dose-to-concentration ratio, DCR) as the prioritization metric. Collections of isomers for the molecular formulae were assembled from the PubChem database and DCR was estimated using partitioning and biotransformation properties predicted for each isomer using quantitative structure property relationships. The ten top-ranked molecular formulae with notably lower average DCR-values represented mostly compounds already known to be indoor pollutants of concern, such as two polybrominated diphenyl ethers, bis(2-ethylhexyl) tetrabromophthalate, tetrabromobisphenol A, tris(1,3-dichloroisopropyl)phosphate and the azo dye disperse blue 373.

}, issn = {2050-7895}, doi = {10.1039/d3em00317e}, author = {Zhang, Zhizhen and Li, Li and Peng, Hui and Wania, Frank} } @article {240, title = {Querying the In Vitro Proteome Cysteine Reactivity of 8:2 Fluorotelomer Acrylate.}, journal = {Environ Sci Technol}, year = {2023}, month = {2023 Aug 22}, abstract = {

Despite the phase out of legacy per- and polyfluoroalkyl substances (PFAS), fluorotelomer-based polymers (FTP) have been used for many applications, notably textile surface coatings. FTPs are of a health concern due to their breakdown into legacy PFAS and the co-occurrence of fluorotelomer acrylate (FTAC) monomers, of which the latter may potentially react with cellular thiols. To evaluate this hypothesis, we employed fluorous-solid-phase extraction (FSPE), to enrich peptides covalently modified by 8:2 fluorotelomer acrylate (8:2 FTAC) and coupled it to a modified nano-liquid chromatography method for the identification of in vitro protein adducts using bottom-up data-dependent proteomics analysis. Using this method, over 100 unique peptides were detected with 8:2 FTAC modifications, although none of the modified cysteine residues were annotated active site nucleophiles. In parallel, a synthetic CF-iodoacetamide (F-IAM) chemical probe was used to gauge the upper bound of PFAS-thiol reactivity. Over seven hundred peptides were detected with modifications but only 9 of 28 annotated active site cysteines in this dataset were modified by F-IAM. Further exploration of the impacts of 8:2 FTAC adducts on protein function revealed that 8:2 FTAC modification promotes protein aggregation in vitro. These results suggest that 8:2 FTAC may exhibit significant proteome thiol reactivity and imply a more general mechanism of toxicity of PFAS-induced protein aggregation.

}, issn = {1520-5851}, doi = {10.1021/acs.est.3c02930}, author = {Hall, David Ross and Gauthier, Jeremy and Peng, Hui} } @article {243, title = {Screening of Indoor Transformation Products of Organophosphates and Organophosphites with an in Silico Spectral Database}, journal = {ACS measurement Science Au (invited article)}, year = {2023}, chapter = {in press}, author = {Kutarna, S and Chen, WZ and Xiong, Y and Liu, RZ and Gong, YF and Peng, H} } @article {230, title = {Thiol Reactome: A Nontargeted Strategy to Precisely Identify Thiol Reactive Drinking Water Disinfection Byproducts}, journal = {Environmental Science and Technology}, year = {2023}, author = {Yeung, KY and Moore, N and Sun, JX and Edmonds, LT and Andrews, S and Hofmann, R and Peng, H} } @article {226, title = {Widespread Presence of Chlorinated Paraffins in Consumer Products}, journal = {Environmental Science: Processes \& Impacts}, year = {2023}, chapter = {in press}, author = {Kutarna, S and Du, X and Diamond, ML and Blum, A and Peng, H} } @article {186, title = {Behaviors and trophodynamics of o,p{\textquoteright}-dichlorodiphenyltrichloroethane (o,p{\textquoteright}-DDT) in the aquatic food web: Comparison with p,p{\textquoteright}-DDT.}, journal = {Sci Total Environ}, year = {2022}, month = {2022 Jan 26}, pages = {153447}, abstract = {

The broad-spectrum insecticide p,p{\textquoteright}-dichlorodiphenyltrichloroethane (p,p{\textquoteright}-DDT) has been banned in most countries since the 1970s on account of its environmental persistence as well as the high biomagnification of its major metabolite 1,1-dichloro-2,2-bis(4-chorophenyl)ethylene (p,p{\textquoteright}-DDE). However, the information on the bioaccumulation and behavior of p,p{\textquoteright}-DDTs in aquatic organisms is lacking. In this study, all 6 DDT isomers were detected in biota from the food web of the Liaodong Bay, China, and the total concentrations of DDT isomers in Chinese anchovy (Thrissa kammalensis) and Japanese Spanish mackerel (Scomberomrus niphonius) were 223 {\textpm} 42 ng/g ww and 242 {\textpm} 70 ng/g ww, respectively. In biota, o,p{\textquoteright}-DDD dominated among the o,p{\textquoteright}-isomers (80.5 {\textpm} 17.3\%), while p,p{\textquoteright}-DDE dominated among the p,p{\textquoteright}-isomers (61.8 {\textpm} 15.2\%). Contrastingly, sediment from the Liaodong Bay contained similar proportions of o,p{\textquoteright}-DDT and p,p{\textquoteright}-DDTs, suggesting an isomer-specific metabolism of the compounds in biota. A well-controlled laboratory exposure experiment with Japanese medaka (Oryzias latipes) demonstrated that o,p{\textquoteright}-DDT was more difficult to metabolize to o,p{\textquoteright}-DDE compared with that of p,p{\textquoteright}-DDT. Significantly positive regressions were found between trophic levels and lipid equivalent concentrations for both o,p{\textquoteright}-DDT and o,p{\textquoteright}-DDD, and the trophic magnification factors (TMFs) were estimated as 12.3 and 9.12 (p \< 0.05), respectively. The TMFs of o,p{\textquoteright}-DDT and o,p{\textquoteright}-DDD in the aquatic food web were higher than p,p{\textquoteright}-DDT (7.76), p,p{\textquoteright}-DDD (4.17), and p,p{\textquoteright}-DDE (3.39), which may be explained by the isomer-specific metabolism differences in biota.

}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2022.153447}, author = {Sun, Jianxian and Xu, Chenke and Peng, Hui and Wan, Yi and Luo, Kai and Barrett, Holly and Hu, Jianying} } @article {209, title = {Chronic toxicity of PFAS-free AFFF alternatives in terrestrial plant Brassica rapa.}, journal = {Sci Total Environ}, year = {2022}, month = {2022 Aug 17}, pages = {158100}, abstract = {

Fluorine (F)-free firefighting foams will be replacing per- and polyfluoroalkyl substances (PFAS)-containing aqueous film-forming foams (AFFFs) at U.S. military installations imminently, yet the environmental impacts of F-free foams are largely unknown. Ecotoxicity assessment of F-free foams is urgently needed to avoid replacement regret. In this study, we comparatively assessed phytotoxicity of six F-free formulations and one current short-chain fluorinated AFFF in terrestrial plant Brassica rapa. Five of six F-free formulations exerted higher toxicity than the short-chain AFFF to the growth and reproduction of B. rapa, with 8-51 times and \> 10 times lower EC values, respectively. Nontargeted analysis indicated the occurrence of transformation products of the test formulations in the above-ground plant tissues. In agreement with their phytotoxicity, the five highly toxic F-free formulations generated more transformation products with higher peak intensities in plant tissues than the two weakly toxic formulations. The most abundant transformation products detected in plant extracts were suspect transformation products derived from diethylene glycol monobutyl ether, a common ingredient of the five toxic formulations. This study provides ecotoxicological data that, combined with data from all related ongoing research, should be used in decision making regarding recommendations for manufacturing and use of candidate F-free foams.

}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2022.158100}, author = {Wu, Xiaoqin* and Nguyen, Helen and Kim, Damian and Peng, Hui*} } @article {199, title = {Community Surveillance of Omicron in Ontario: Wastewater-based Epidemiology Comes of Age}, journal = {Research Square}, year = {2022}, author = {Arts, E and Brown, S and Bulir, D and Charles, TC and DeGroot, CT and Delatolla, R and Desaulniers, JP and Edwards, EA and Fuzzen, M and Gilbride, K and Gilchrist, J and Goodridge, L and Graber, T and Habash, M and Juni, P and Kirkwood, A and Knockleby, J and Kyle, C and Landgraff, C and Mangat, C and Manuel, DG and McKay, RM and Mejia, E and Mloszewska, A and Ormeci, B and Oswald, C and Payne, SJ and Peng, H and Peterson, S and Poon, A and Servos, MR and Simmons, D and Sun, JX and Yang MQ and Ybazeta, G} } @article {217, title = {Defining the Chemical Additives Driving In Vitro Toxicities of Plastics}, journal = {Environ. Sci. Technol.}, year = {2022}, author = {Chen, Wanzhen and Gong, Yufeng and Michael, McKie and Husein, Almuhtaram and Sun, Jianxian and Barrett, Holly and Yang, Diwen and Wu, Menghong and Andrews, Robert and Peng, Hui} } @article {202, title = {Early Warning Measurement of SARS-CoV-2 Variants of Concern in Wastewaters by Mass Spectrometry}, journal = {Environ. Sci. Technol. Lett}, year = {2022}, month = {06/2022}, author = {Peng, JX and Sun, JX and Yang, MQ and Gibson, R and Arts, E and Olabode, AS and Poon, AF and Wang, XY and Wheeler, AR and Edwards, E and Peng, H} } @article {189, title = {Long-term trends of fluorotelomer alcohols in a wastewater treatment plant impacted by textile manufacturing industry.}, journal = {Chemosphere}, year = {2022}, month = {2022 Mar 25}, pages = {134442}, abstract = {

Fluorotelomer alcohols (FTOHs) are important precursors and substitutes of perfluoroalkyl carboxylic acids (PFCAs). This study investigated the long-term trends of FTOHs in a municipal wastewater treatment plant impacted by textile manufacturing industry (T-WWTP) in Wuxi city from 2013 to 2021. For comparison, four domestic wastewater treatment plants (D-WWTPs) were also selected for the investigation. The total concentrations of FTOHs, which were 9.8-43 ng/L, 5.9-29 ng/L and 10-50 ng/g in influent, effluent, and sludge samples from the T-WWTP, were significantly higher than those of the D-WWTPs (p \< 0.01). The significant correlation between decrease of mass loads for FTOH and the increase for PFCAs was observed, suggesting the potential biotransformation of FTOHs to PFCAs. Concentration variation in FTOH concentrations was observed for the T-WWTP, which was in accord with the variation in annual output of textile products in Wuxi city (p = 0.005). The predominance of 8:2 FTOH in the influents of T-WWTP between 2013 and 2016 switched over to 6:2 FTOH in 2020-2021. This work highlighted the textile manufacturing industry as a significant discharge route for FTOHs to municipal WWTP, as well as the dramatic change in the usage of FTOHs in the textile manufacturing industry in Wuxi.

}, issn = {1879-1298}, doi = {10.1016/j.chemosphere.2022.134442}, author = {Ma, Chunmeng and Peng, Hui and Chen, Hongrui and Shang, Wei and Zheng, Xingcan and Yang, Min and Zhang, Yu} } @article {211, title = {Measuring Perfluoroalkyl Acid Contamination at a Local Hot Spot: An Authentic Field-Based Laboratory Experience in a Senior Analytical Environmental Chemistry Course}, journal = {Journal of Chemical Education}, year = {2022}, author = {Joudan, Shira and Barrett, Holly and Silva, Amila O De and Solla, Shane R and Peng, Hui and Deon, Jessica C} } @article {205, title = {The omega-3 hydroxy fatty acid 7(S)-HDHA is a high-affinity PPARα ligand that regulates brain neuronal morphology}, journal = {Science Signaling}, year = {2022}, author = {Liu, JB and Sahin, C and Ahmad, S and Magomedova, L and Zhang, MH and Jia, ZP and Metherel, AH and Orellana, A and Poda, G and Bazinet, RP and Attisano, L and Cummins, CL and Peng, H* and Krause, H*} } @article {215, title = {Per- and Polyfluoroalkyl Substances in North American School Uniforms.}, journal = {Environ Sci Technol}, year = {2022}, month = {2022 Sep 21}, abstract = {

We analyzed 72 children{\textquoteright}s textile products marketed as stain-resistant from US and Canadian stores, particularly school uniforms, to assess if clothing represents a significant route of exposure to per- and polyfluoroalkyl substances (PFAS). Products were first screened for total fluorine (total F) using particle-induced γ-ray emission (PIGE) spectroscopy ( = 72), followed by targeted analysis of 49 neutral and ionic PFAS ( = 57). PFAS were detected in all products from both markets, with the most abundant compound being 6:2 fluorotelomer alcohol (6:2 FTOH). Total targeted PFAS concentrations for all products collected from both countries ranged from 0.250 to 153 000 ng/g with a median of 117 ng/g (0.0281-38 100 μg/m, median: 24.0 μg/m). Total targeted PFAS levels in school uniforms were significantly higher than in other items such as bibs, hats, stroller covers, and swimsuits, but comparable to outdoor wear. Higher total targeted PFAS concentrations were found in school uniforms made of 100\% cotton than synthetic blends. Perfluoroalkyl acids (PFAAs) precursors were abundant in school uniforms based on the results of hydrolysis and total oxidizable precursor assay. The estimated median potential children{\textquoteright}s exposure to PFAS via dermal exposure through school uniforms was 1.03 ng/kg bw/day. Substance flow analysis estimated that \~{}3 tonnes/year (ranging from 0.05 to 33 tonnes/year) of PFAS are used in US children{\textquoteright}s uniforms, mostly of polymeric PFAS but with \~{}0.1 tonne/year of mobile, nonpolymeric PFAS.

}, issn = {1520-5851}, doi = {10.1021/acs.est.2c02111}, author = {Xia, Chunjie and Diamond, Miriam L and Peaslee, Graham F and Peng, Hui and Blum, Arlene and Wang, Zhanyun and Shalin, Anna and Whitehead, Heather D and Green, Megan and Schwartz-Narbonne, Heather and Yang, Diwen and Venier, Marta} } @article {198, title = {Quantitative Trend Analysis of SARS-CoV-2 RNA in Municipal Wastewater Exemplified with Sewershed-Specific COVID-19 Clinical Case Counts}, journal = {ACS ES\&T Water}, volume = {2}, year = {2022}, month = {05/2022}, author = {Pileggi, V and Shurgold, J and Sun, JX and Yang, MQ and Edwards, E and Peng, H and Tehrani A and Gilbride, KA and Oswald CJ and Wijayasri, S and AI-Bargash, D and Stuart, R and Khansari, Z and Raby, M and Thomas, J and Fletcher, T and Simon, A} } @article {196, title = {Triclosan is the Predominant Antibacterial Compound in Ontario Sewage Sludge}, journal = {Environmental Science and Technology}, volume = {56}, year = {2022}, author = {Barrett, Holly and Sun, Jianxian and Gong, Yufeng and Yang, Paul and Hao, Chunyan and Verreault, Jonathan and Zhang, Yu and Peng, Hui} } @article {212, title = {Wastewater to clinical case (WC) ratio of COVID-19 identifies insufficient clinical testing, onset of new variants of concern and population immunity in urban communities.}, journal = {Sci Total Environ}, year = {2022}, month = {2022 Sep 03}, pages = {158547}, abstract = {

Clinical testing has been the cornerstone of public health monitoring and infection control efforts in communities throughout the COVID-19 pandemic. With the anticipated reduction of clinical testing as the disease moves into an endemic state, SARS-CoV-2 wastewater surveillance (WWS) will have greater value as an important diagnostic tool. An in-depth analysis and understanding of the metrics derived from WWS is required to interpret and utilize WWS-acquired data effectively (McClary-Gutierrez et al., 2021; O{\textquoteright}Keeffe, 2021). In this study, the SARS-CoV-2 wastewater signal to clinical cases (WC) ratio was investigated across seven cities in Canada over periods ranging from 8 to 21 months. This work demonstrates that significant increases in the WC ratio occurred when clinical testing eligibility was modified to appointment-only testing, identifying a period of insufficient clinical testing (resulting in a reduction to testing access and a reduction in the number of daily tests) in these communities, despite increases in the wastewater signal. Furthermore, the WC ratio decreased significantly in 6 of the 7 studied locations, serving as a potential signal of the emergence of the Alpha variant of concern (VOC) in a relatively non-immunized community (40-60 \% allelic proportion), while a more muted decrease in the WC ratio signaled the emergence of the Delta VOC in a relatively well-immunized community (40-60 \% allelic proportion). Finally, a significant decrease in the WC ratio signaled the emergence of the Omicron VOC, likely because of the variant{\textquoteright}s greater effectiveness at evading immunity, leading to a significant number of new reported clinical cases, even when community immunity was high. The WC ratio, used as an additional monitoring metric, could complement clinical case counts and wastewater signals as individual metrics in its potential ability to identify important epidemiological occurrences, adding value to WWS as a diagnostic technology during the COVID-19 pandemic and likely for future pandemics.

}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2022.158547}, author = {D{\textquoteright}Aoust, Patrick M and Tian, Xin and Towhid, Syeda Tasneem and Xiao, Amy and Mercier, Elisabeth and Hegazy, Nada and Jia, Jian-Jun and Wan, Shen and Kabir, Md Pervez and Fang, Wanting and Fuzzen, Meghan and Hasing, Maria and Yang, Minqing Ivy and Sun, Jianxian and Plaza-Diaz, Julio and Zhang, Zhihao and Cowan, Aaron and Eid, Walaa and Stephenson, Sean and Servos, Mark R and Wade, Matthew J and MacKenzie, Alex E and Peng, Hui and Edwards, Elizabeth A and Pang, Xiao-Li and Alm, Eric J and Graber, Tyson E and Delatolla, Robert} } @article {218, title = {Widespread formation of toxic nitrated-bisphenols indoors by heterogeneous reactions with HONO}, journal = {Science Advances}, year = {2022}, author = {Yang, Diwen and Liu, Qifan and Wang, Sizhi and Bozorg, Martin and Liu, Jiabao and Nair, Pranav and Balaguer, Patrick and Song, Datong and Krause, Henry and Ouazia, Boualem and Abbatt, Jonathan and Peng, Hui} } @article {183, title = {Ecological Role of 6OH-BDE47: Is It a Chemical Offence Molecule Mediated by Enoyl-ACP Reductases?}, journal = {Environ. Sci. Technol.}, year = {2021}, author = {Sun, Jianxian and Barrett, Holly and Hall, David and Kutarna, Steven and Wu, Xiaoqin and Wang, Yan and Peng, Hui} } @article {173, title = {Enhanced Nontarget Screening Algorithm Reveals Highly Abundant Chlorinated Azo Dye Compounds in House Dust}, journal = {Environ. Sci. Technol.}, volume = {55}, year = {2021}, abstract = {

Humans spend 90\% of their time indoors, but the majority of indoor pollutants remain unknown. In this study, a nontarget screening algorithm with reduced false discovery rates was developed to screen indoor pollutants using the Toxic Substances Control Act (TSCA) database. First, a Putative Lock Mass Algorithm was developed for post-acquisition calibration of Orbitrap mass spectra to sub-ppm mass accuracy. Then, a one-stop screening algorithm was developed by combining MS1 spectra, isotopic peaks, retention time prediction, and in silico MS2 spectra. Sufficient true positive rate (73\%) and false discovery rate (5\%) were achieved for the screening of halogenated compounds at a score cut-off of 0.28. Above this cut-off, 427 chemicals were detected from 24 house dust samples, including 39 chlorinated compounds. While some identified halogenated compounds (e.g., triclosan) are well known, 18 previously unrecognized chlorinated azo dyes were detected with high abundance as the largest class of chlorinated compounds. Two chlorinated azo dyes were confirmed by authentic standards, but the two most abundant chlorinated azo dyes were missed by the algorithm due to the limited breadth of the TSCA database. These compounds were annotated as chlorinated analogues of Disperse Blue 373 and Disperse Violet 93 using the DIPIC-Frag method.This study revealed the presence of highly abundant chlorinated azo dyes in house dusts, highlighting their potential health risks in the indoor environment.

}, author = {Steven Kutarna and Song Tang and Xiaojian Hu and Hui Peng} } @article {178, title = {Quantitative Chemical Proteomics Reveals Interspecies Variations on Binding Schemes of L-FABP with Perfluorooctanesulfonate}, journal = {Environ. Sci. Technol.}, volume = {55}, year = {2021}, abstract = {

Evaluating interspecies toxicity variation is a long-standing challenge for chemical hazard assessment. This study developed a Quantitative Interspecies Thermal Shift Assay (QITSA) for in-situ, quantitative, and modest-throughput investigation of chemical-protein interactions in cell and tissue samples across species. By using liver fatty acid binding protein (L-FABP) as a case study, the QITSA method was benchmarked with six per- and polyfluoroalkyl substances (PFAS) and thermal shifts (∆Tm) were inversely related to their dissociation constants (R2=0.98). QITSA can also distinguish binding modes of chemicals exemplified by palmitic acid. The QITSA was applied to determine the interactions between perfluorooctanesulfonate(PFOS) and L-FABP in liver cells or tissues from human, mouse, rat, and zebrafish. The largest thermal stability enhancement by PFOS was observed for human L-FABP, followed by mouse, rat and zebrafish. While endogenous ligands were revealed to partially contribute to the large interspecies variation, recombinant proteins were employed to confirm the high binding affinity of PFOS to human L-FABP, compared to rat and mouse. This study implemented an experimental strategy to characterize chemical-protein interactions across species and future application of QITSA to other chemical contaminants is of great interest.

}, author = {Han, JJ and Fu, J and Sun, JX and Hall, DR and Yang, DW and Blatz, D and Houck, KA and Ng, CA and Doering, JA and LaLone, CA and Peng, H} } @article {175, title = {A Roadmap to the Structure-Related Metabolism Pathways of Per- and Polyfluoroalkyl Substances in the Early Life Stages of Zebrafish (Danio rerio)}, journal = {Environ. Health. Perspect.}, volume = {129}, year = {2021}, abstract = {

BACKGROUND: Thousands of per- and polyfluoroalkyl substances (PFAS) with diverse structures have been detected in the ambient environment. Apart from a few well studied PFAS, the structure-related toxicokinetics of a broader set of PFAS remain unclear.

OBJECTIVES: To understand the toxicokinetics of PFAS, we attempted to characterize the metabolism pathways of 74 structurally diverse PFAS samples from the U.S. EPA{\textquoteright}s PFAS screening library.

METHODS: Using the early life stages of zebrafish (Danio rerio) as a model, we determined the bioconcentration factors and phenotypic toxicities of 74 PFAS. Then, we applied High-Resolution Mass Spectrometry based non-targeted analysis to identify metabolites of PFAS in zebrafish larvae after five days of exposure, by incorporating retention time and mass spectra. In vitro enzymatic activity experiments with human recombinant liver carboxylesterase (hCES1) were employed to validate the structure-related hydrolysis of 11 selected PFASs.

RESULTS: Our findings identified five structural categories of PFAS prone to metabolism. The metabolism pathways of PFAS are highly related to their structures as exemplified by fluorotelomer alcohols that the predominance of β-oxidation or taurine conjugation pathways were primarily determined by the number of hydrocarbons. Hydrolysis is a major metabolism pathway for diverse PFAS and perfluoroalkyl carboxamides showed the highest in vivo hydrolysis rates, followed by carboxyesters and sulfonamides. The hydrolysis of PFAS was verified with recombinant hCES1, with strong substrate preferences towards perfluoroalkyl carboxamides.

CONCLUSIONS:We suggest that the roadmap of the structure-related metabolism pathways of PFAS established in this study would provide a starting point to inform the potential health risks of other PFAS.

}, author = {Han, JJ and Gu, W and Barrett, H and Yang, DW and Tang, S and Sun, JX and Liu, JB and Krause, HM and Houck, KA and Peng, H} } @article {145, title = {Suspect and Nontarget Screening Revealed Class-Specific Temporal Trends (2000-2017) of Poly- and Perfluoroalkyl Substances in St. Lawrence Beluga Whales.}, journal = {Environ Sci Technol}, year = {2021}, month = {2021 Jan 14}, abstract = {

The global use of \>3000 per- and polyfluoroalkyl substances (PFASs) has given rise to chemical regulatory action. However, limited information exists regarding current and historical emissions for the majority of PFASs under currently implemented regulations. This study employed suspect and nontarget screening to examine the temporal trends of legacy and unregulated PFASs in liver of the endangered beluga whale () population from the St. Lawrence Estuary in Canada collected from 2000 to 2017. A suite of 54 PFASs were tentatively identified, and were grouped into nine structurally distinct classes. Single-hydrogenated perfluoro carboxylic acids (H-PFCAs), single-hydrogenated sulfonamides (H-Sulfonamides), as well as other select sulfonamides were detected for the first time in wildlife. Greater concentrations of the majority of PFASs were determined in newborns and juveniles than in adults, suggesting effective placental and lactational transfer of PFASs. Legacy per- and polyfluoroalkyl acids and perfluorooctane sulfonamide in beluga whale liver were found to significantly decrease in concentration between 2000 and 2017, while unregulated short-chain PFAS alternatives, H-PFCAs, and odd-chain FTCAs were found to increase over time. The implementation of suspect and nontarget screening revealed class-specific temporal trends of PFASs in SLE beluga whales, and supported continuous emissions of unregulated PFASs into the environment.

}, issn = {1520-5851}, doi = {10.1021/acs.est.0c05957}, author = {Barrett, Holly and Du, Xuan and Houde, Magali and Lair, St{\'e}phane and Verreault, Jonathan and Peng, Hui} } @article {135, title = {Characterizing physical protein targets of chemical contaminants with chemical proteomics: Is it time to fill a crucial environmental toxicology knowledge gap?}, journal = {Comp Biochem Physiol Part D Genomics Proteomics (invited perspective)}, volume = {34}, year = {2020}, month = {2020 Jun}, pages = {100655}, abstract = {

Current environmental toxicological studies are challenged by the immense number (\>80,000) of chemical contaminants. While several strategies including adverse outcome pathway (AOP), High-Throughput Screening (HTS), and computational toxicology have been proposed to tackle this challenge, we argue here that characterizing the protein targets of chemical contaminants is the major bottleneck. In this commentary article, we reviewed current environmental toxicology research, and pinpointed the urgency to identify physical protein targets of chemical contaminants. We also reviewed several chemical proteomics methodologies developed in our and other groups, and their advantages and disadvantages to identify protein targets. At the end of the article, we also pointed out several potential follow-up research directions should be pursued once protein targets are identified.

}, issn = {1878-0407}, doi = {10.1016/j.cbd.2020.100655}, author = {Hall, David Ross and Peng, Hui} } @article {139, title = {Mechanisms of pH-Dependent Uptake of Ionizable Organic Chemicals by Fish from Oil Sands Process-Affected Water (OSPW).}, journal = {Environ Sci Technol}, volume = {54}, year = {2020}, month = {2020 Aug 04}, pages = {9547-9555}, abstract = {

Uptake and effects of ionizable organic chemicals (IOCs) that are weak acids in aqueous solution by fish can differ as a function of pH. While the pH-dependent behavior of select IOCs is well-understood, complex mixtures of IOCs, e.g., from oil sands process-affected water (OSPW), have not yet been studied systematically. Here, we established an in vitro screening method using the rainbow trout gill cell line, RTgill-W1, to investigate pH-dependent cytotoxicity and permeation of IOCs across cultured epithelia using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UPLC-HRMS). The assay was benchmarked using model chemicals and technical mixtures, and then used to characterize fractions and reconstituted extracts of field-collected OSPW. Significant pH-dependent cytotoxicity of individual IOCs, acidic fractions, and reconstituted extracts of OSPW was observed. In vitro data were in good agreement with data from a 96 h in vivo exposure experiment with juvenile rainbow trout. Permeation of some IOCs from OSPW was mediated by active transport, as revealed by studies in which inhibitors of these active transport mechanisms were applied. We conclude that the RTgill-W1 in vitro assay is useful for the screening of pH-dependent uptake of IOCs in fish, and has applications for in vitroin vivo extrapolation, and prioritization of chemicals in nontarget screenings.

}, issn = {1520-5851}, doi = {10.1021/acs.est.0c02522}, author = {Brinkmann, Markus and Alharbi, Hattan and Fuchylo, Ulyana and Wiseman, Steve and Morandi, Garrett and Peng, Hui and Giesy, John P and Jones, Paul D and Hecker, Markus} } @article {141, title = {Monohaloacetic Acids and Monohaloacetamides Attack Distinct Cellular Proteome Thiols}, journal = {Environ. Sci. Technol.}, volume = {54}, year = {2020}, chapter = {in press}, author = {Hall, DR and Yeung, K and Peng, H} } @article {138, title = {Nontarget Screening of Per- and Polyfluoroalkyl Substances Binding to Human Liver Fatty Acid Binding Protein}, journal = {Environ. Sci. Technol.}, volume = {54}, year = {2020}, chapter = {5676-5686}, author = {Yang, DW and Han, JJ and Hall, DR and Sun, JX and Fu, J and Kutarna, S and Houck, KA and LaLone, CA and Doering, JA and Ng, CA and Peng, H} } @article {140, title = {Proteome-wide effects of naphthalene-derived secondary organic aerosol in BEAS-2B cells are caused by short-lived unsaturated carbonyls.}, journal = {Proc Natl Acad Sci U S A}, year = {2020}, month = {2020 Sep 28}, abstract = {

Exposure to air pollution causes adverse health outcomes, but the toxicity mechanisms remain unclear. Here, we investigated the dynamic toxicities of naphthalene-derived secondary organic aerosol (NSOA) in a human bronchial epithelial cell line (BEAS-2B) and identified the chemical components responsible for toxicities. The chemical composition of NSOA was found to vary with six simulated atmospheric aging conditions (C-C), as characterized by high-resolution mass spectrometry and ion mobility mass spectrometry. Global proteome profiling reveals dynamic evolution in toxicity: Stronger proteome-wide impacts were detected in fresh NSOA, but the effects declined along with atmospheric aging. While Nrf2-regulated proteins (e.g., ) were significantly up-regulated, the majority (78 to 97\%) of proteins from inflammation and other pathways were down-regulated by NSOA exposure (e.g., ). This pattern is distinct from the reactive oxygen species (ROS)-mediated toxicity pathway, and an alternative cysteine reaction pathway was revealed by the decreased abundance of proteins (e.g., ) prone to posttranslational thiol modification. This pathway was further validated by observing decreased Nrf2 response in reporter cells, after preincubating NSOA with cysteine. Ethynyl-naphthalene probe was employed to confirm the alkylation of cellular proteome thiols on the proteome-wide level by fresh NSOA via in-gel fluorescence imaging. Nontarget analysis identified several unsaturated carbonyls, including naphthoquinones and hydroxylated naphthoquinones, as the toxic components responsible for cysteine reactivity. Our study provides insights into the dynamic toxicities of NSOA during atmospheric aging and identifies short-lived unsaturated carbonyls as the predominant toxic components at the posttranslational level.

}, issn = {1091-6490}, doi = {10.1073/pnas.2001378117}, author = {Han, Jiajun and Wang, Shunyao and Yeung, Kirsten and Yang, Diwen and Gu, Wen and Ma, Zhiyuan and Sun, Jianxian and Wang, Xiaomin and Chow, Chung-Wai and Chan, Arthur W H and Peng, Hui} } @article {130, title = {Toxicokinetics of Brominated Azo Dyes in the Early Life Stages of Zebrafish () Is Prone to Aromatic Substituent Changes.}, journal = {Environ Sci Technol}, volume = {54}, year = {2020}, month = {2020 04 07}, pages = {4421-4431}, abstract = {

Brominated azo dyes (BADs) have been identified as predominant indoor brominated pollutants in daycare dust; thus, their potential health risk to children is of concern. However, the toxicities of BADs remain elusive. In this study, the toxicokinetics of two predominant BADs, Disperse Blue 373 (DB373) and Disperse Violet 93 (DV93), and their suspect metabolite 2-bromo-4,6-dinitroaniline (BDNA) was investigated in embryos of zebrafish (). The bioconcentration factor of DV93 at 120 hpf is 6.2-fold lower than that of DB373. The nontarget analysis revealed distinct metabolism routes between DB373 and DV93 by reducing nitro groups to nitroso (DB373) or amine (DV93), despite their similar structures. NAD(P)H quinone oxidoreductase 1 (NQO1) and pyruvate dehydrogenase were predicted as the enzymes responsible for the reduction of DB373 and DV93 by correlating time courses of the metabolites and enzyme development. Further in vitro recombinant enzyme and in vivo inhibition results validated NQO1 as the enzyme specifically reducing DB373, but not DV93. Global proteome profiling revealed that the expression levels of proteins from the "apoptosis-induced DNA fragmentation" pathway were significantly upregulated by all three BADs, supporting the bioactivation of BADs to mutagenic aromatic amines. This study discovered the bioactivation of BADs via distinct eukaryotic enzymes, implying their potential health risks.

}, keywords = {Animals, Azo Compounds, Child, Dust, Embryo, Nonmammalian, Humans, Mutagens, Toxicokinetics, Zebrafish}, issn = {1520-5851}, doi = {10.1021/acs.est.9b07178}, author = {Han, Jiajun and Yang, Diwen and Hall, David Ross and Liu, Jiabao and Sun, Jianxian and Gu, Wen and Tang, Song and Alharbi, Hattan A and Jones, Paul D and Krause, Henry M and Peng, Hui} } @article {129, title = {Abundances and concentrations of brominated azo dyes detected in indoor dust.}, journal = {Environ Pollut}, volume = {252}, year = {2019}, month = {2019 Sep}, pages = {784-793}, abstract = {

Dust samples were collected from four indoor environments, including childcare facilities, houses, hair salons, and a research facility from the USA and were analyzed for brominated compounds using full scan liquid chromatography high-resolution mass spectrometry. A total of 240 brominated compounds were detected in these dust samples, and elemental formulas were predicted for 120 more abundant ions. In addition to commonly detected brominated flame retardants (BFRs), nitrogen-containing brominated azo dyes (BADs) were among the most frequently detected and abundant. Specifically, greater abundances of BADs were detected in indoor dusts from daycares and salons compared to houses and the research facility. Using authentic standards, a quantitative method was established for two BADs (DB373: Disperse Blue 373 and DV93: Disperse Violet 93) and 2-bromo-4,6-dinitroaniline, a commonly used precursor in azo dye production, in indoor dust. Generally, greater concentrations of DB373 (<=3850 ng/g) and DV93 (<=1190 ng/g) were observed in indoor dust from daycares highlighting children as a susceptible population to potential health risk from exposure to BADs. These data are important because, to date, targeted analysis of brominated compounds in indoor environments has focused mainly on BFRs and appears to underestimate the total amount of brominated compounds.

}, keywords = {Air Pollution, Indoor, Aniline Compounds, Azo Compounds, Child, Child Day Care Centers, Chromatography, Liquid, Dust, Flame Retardants, Halogenated Diphenyl Ethers, Humans, Hydrocarbons, Brominated, Nitrogen, Tandem Mass Spectrometry}, issn = {1873-6424}, doi = {10.1016/j.envpol.2019.05.153}, author = {Dhungana, Birendra and Peng, Hui and Kutarna, Steven and Umbuzeiro, Gisela and Shrestha, Sujan and Liu, Jing and Jones, Paul D and Subedi, Bikram and Giesy, John P and Cobb, George P} } @article {81, title = {Acid mine drainage affects the diversity and metal resistance gene profile of sediment bacterial community along a river}, journal = {Chemosphere}, volume = {217}, year = {2019}, month = {Date}, pages = {790-199}, doi = {10.1016/j.chemosphere.2018.10.210}, url = {https://www.sciencedirect.com/science/article/pii/S004565351832085X}, author = {Xiaohui Zhang and Song Tang and Mao Wang and Weimin Sun and Yuwei Xie and Hui Peng and Aimin Zhong and Hongling Liu and Xiaowei Zhang and Hongxia Yu and John P. Giesy and Markus Hecker} } @article {82, title = {Relationship between perfluorooctanoate and perfluorooctane sulfonate blood concentrations in the general population and routine drinking water exposure.}, journal = {Environ Int}, volume = {126}, year = {2019}, month = {2019 Feb 15}, pages = {54-60}, abstract = {

In regions with heavily contaminated drinking water, a significant contribution of drinking water to overall human perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) exposure has been well documented. However, the relationship of PFOA/PFOS blood concentrations in the general population to routine drinking water exposure is not well characterized. This study determined the PFOA and PFOS concentrations in 166 drinking water samples across 28 cities in China. For 13 of the studied cities, PFOA and PFOS concentrations were analyzed in 847 human blood samples which were collected in parallel with the drinking water samples. The geometric mean PFOA and PFOS concentrations in drinking water were 2.5 {\textpm} 6.2 ng/L and 0.7 {\textpm} 11.7 ng/L, and population-weighted geometric mean blood concentrations were 2.1 {\textpm} 1.2 ng/mL and 2.6 {\textpm} 1.3 ng/mL, respectively. We found a significant correlation between the PFOA concentration in drinking water and blood (r = 0.87, n = 13, p \< 0.001). The total daily intake of PFOA (0.24-2.13 ng/kg/day) and PFOS (0.19-1.87 ng/kg/day) were back-calculated from the blood concentrations with a one-compartment toxicokinetic model. We estimated relative source contributions (RSCs) of drinking water to total daily intake in China of 23 {\textpm} 3\% for PFOA and 12.7 {\textpm} 5.8\% for PFOS. Using the mean RSCs, we derived the health advisory values of 85 ng/L for PFOA and 47 ng/L for PFOS in China.

}, issn = {1873-6750}, doi = {10.1016/j.envint.2019.02.009}, author = {Zhang, Shiyi and Kang, Qiyue and Peng, Hui and Ding, Mengyu and Zhao, Fanrong and Zhou, Yuyin and Dong, Zhaomin and Zhang, Haifeng and Yang, Min and Tao, Shu and Hu, Jianying} } @article {127, title = {Screening of House Dust from Chinese Homes for Chemicals with Liver X Receptors Binding Activities and Characterization of Atherosclerotic Activity Using an Macrophage Cell Line and Mice.}, journal = {Environ Health Perspect}, volume = {127}, year = {2019}, month = {2019 11}, pages = {117003}, abstract = {

BACKGROUND: Atherosclerotic cardiovascular disease has become the leading cause of death worldwide, and environmental pollutants are increasingly recognized as risk factors for atherosclerosis. Liver X receptors (LXRs) play a central role in atherosclerosis; however, LXR activity of organic pollutants and associated potential risk of atherosclerosis have not yet been characterized.

OBJECTIVES: This study aimed to explore whether LXR-antagonistic chemicals are present in indoor house dust and, if so, to characterize this activity in relation to changes in macrophages and cardiovascular disease indicators in an atherosclerosis mouse model.

METHODS: We used a -down assay and a nontarget high-resolution mass spectrometry method to screen house dust collected from Chinese homes for - and -antagonist activity. A chemical identified in this manner was assessed for its ability to induce cholesterol efflux and foam cell formation in RAW264.7 macrophages, to down-regulate the expression of two LXR-dependent genes, and , and finally to induce atherosclerotic lesions using an mouse model.

RESULTS: We identified the flame retardants triphenyl phosphate (TPHP) and 2-ethylhexyl diphenyl phosphate (EHDPP) in house dust samples and demonstrated their ability to antagonize LXRs. The potency of TPHP was similar to that of the LXR-antagonist SR9238. TPHP could also inhibit cholesterol efflux and promote foam cell formation in RAW264.7 macrophages and mouse peritoneal macrophages and significantly promoted atherosclerotic lesion formation in the mouse model.

CONCLUSIONS: We found LXR-antagonist chemicals in environmental samples of indoor dust from Chinese homes. One of the chemicals, TPHP, was able to promote the development of atherosclerotic lesions in the mouse model. These results highlight the need to assess the LXR-antagonist activities of pollutants in future environmental management programs. https://doi.org/10.1289/EHP5039.

}, keywords = {Air Pollutants, Air Pollution, Indoor, Animals, Atherosclerosis, China, Dust, Liver X Receptors, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, ApoE, RAW 264.7 Cells}, issn = {1552-9924}, doi = {10.1289/EHP5039}, author = {Hu, Wenxin and Jia, Yingting and Kang, Qiyue and Peng, Hui and Ma, Haojia and Zhang, Shiyi and Hiromori, Youhei and Kimura, Tomoki and Nakanishi, Tsuyoshi and Zheng, Lemin and Qiu, Yifu and Zhang, Zhaobin and Wan, Yi and Hu, Jianying} } @article {128, title = {Underlying mechanisms of reproductive toxicity caused by multigenerational exposure of 2, bromo-4, 6-dinitroaniline (BDNA) to Zebrafish (Danio rerio) at environmental relevant levels.}, journal = {Aquat Toxicol}, volume = {216}, year = {2019}, month = {2019 Nov}, pages = {105285}, abstract = {

2-bromo-4, 6-dinitroaniline (BDNA) is a mutagenic aromatic amine involved in the production and degradation of Disperse blue 79, one of the most extensively used brominated azo dyes. In our previous study, a multigenerational exposure of BDNA (0.5, 5, 50 and 500 μg/L) to zebrafish from F adult to F larvae including a recovery group in F larvae was conducted. The effects on apical points observed in individuals and the long-term effects predicted on population were all related to reproduction. In this study, we performed molecular analysis to elucidate the underlying mechanisms of the reproductive toxicity of BDNA. In F generation, measurement of vitellogenin and transcription levels of genes associated with hypothalamus-pituitary-gland (HPG) axis, estrogen receptor (ER) and androgen receptor (AR) were conducted. There was a decrease in VTG level in the blood of F female fish and transcription of genes related to ER was more affected than that of genes related to AR. These results were consistent with adverse effects that sexual differentiation was biased towards males and fecundity was impaired in a concentration-dependent manner in adults of F generation after 150 days exposure. In F generation, global gene transcriptions of F larvae were investigated. It was uncovered that processes related to apoptosis, development and DNA damage were strongly affected. Alterations to these biological pathways accounted for the irreversible parental influence on a significant decrease in hatchability and increase in abnormality of F larvae. All evidence suggested that the multigenerational exposure of BDNA posed lasting effects transmitted from parents to offspring that persisted after exposure ceased.

}, keywords = {Aniline Compounds, Animals, DNA Damage, Environmental Exposure, Female, Larva, Male, Principal Component Analysis, Reproduction, Toxicity Tests, Transcription, Genetic, Transcriptome, Vitellogenins, Water Pollutants, Chemical, Zebrafish}, issn = {1879-1514}, doi = {10.1016/j.aquatox.2019.105285}, author = {Xie, Xianyi and Jin, Yaru and Ma, Zhiyuan and Tang, Song and Peng, Hui and Giesy, John P and Liu, Hongling} } @article {86, title = {Current and historical concentrations of poly and perfluorinated compounds in sediments of the northern Great Lakes - Superior, Huron, and Michigan.}, journal = {Environ Pollut}, volume = {236}, year = {2018}, month = {2018 May}, pages = {373-381}, abstract = {

Current and historical concentrations of 22 poly- and perfluorinated compounds (PFASs) in sediment collected from Lake Superior and northern Lake Michigan in 2011 and Lake Huron in 2012 are reported. The sampling was performed in two ways, Ponar grabs of surface sediments for current spatial distribution across the lake and dated cores for multi-decadal temporal trends. Mean concentrations of the sum of PFASs (∑PFASs) were 1.5, 4.6 and 3.1 ng g dry mas (dm) in surface sediments for Lakes Superior, Michigan and Huron, respectively. Of the five Laurentian Lakes, the watersheds of Superior and Huron are the less densely populated by humans, and concentrations observed were typically less and from more diffuse sources, due to lesser urbanization and industrialization. However, some regions of greater concentrations were observed and might indicate more local, point sources. In core samples concentrations ranged from 7 that include perfluoro-n-octane sulfonate (PFOS) bind more strongly to sediment, which resulted in more accurate analyses of temporal trends. Shorter-chain PFASs, such as perfluoro-n-butanoic acid which is the primary replacement for C8 PFASs that have been phased out, are more soluble and were identified in some core layers at depths corresponding to pre-production periods. Thus, analyses of temporal trends of these more soluble compounds in cores of sediments were less accurate. Total elemental fluorine (TF) and extractable organic fluorine (EOF) indicated that identified PFASs were not a significant fraction of fluorine containing compounds in sediment (\<0.01\% in EOF).

}, keywords = {Environmental Monitoring, Fluorocarbons, Geologic Sediments, Great Lakes Region, Lakes, Water Pollutants, Chemical}, issn = {1873-6424}, doi = {10.1016/j.envpol.2018.01.065}, author = {Codling, Garry and Hosseini, Soheil and Corcoran, Margaret B and Bonina, Solidea and Lin, Tian and Li, An and Sturchio, Neil C and Rockne, Karl J and Ji, Kyunghee and Peng, Hui and Giesy, John P} } @article {83, title = {Multigenerational Effects and Demographic Responses of Zebrafish ( Danio rerio) Exposed to Organo-Bromine Compounds.}, journal = {Environ Sci Technol}, volume = {52}, year = {2018}, month = {2018 Aug 07}, pages = {8764-8773}, abstract = {

Long-term exposure to toxic chemicals often has deleterious effects on aquatic organisms. In order to support appropriate environmental management of chemicals, a mathematical model was developed to characterize the effects of chemicals on multigenerational population dynamics in aquatic animals. To parametrize the model, we conducted a multigenerational laboratory toxicity test in zebrafish ( Danio rerio) exposed to 2-bromo-4,6-dinitroaniline (BDNA). Long-term exposure to BDNA considerably reduced the fecundity of adult zebrafish (F and F) and caused deformities in the offspring (F). Life history data, including changes in fecundity and population growth, were then integrated into the model to predict population dynamics of zebrafish exposed to two novel brominated flame retardants, bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH) and 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB). The model predicted that the fecundity of adult zebrafish would be significantly impaired after exposure to 90.36 μM TBPH and 99.16 μM TBB. Thus, prolonged exposure to such levels over multiple generations could result in population extinction within 20 years. Our results provide an intensive temporal perspective to investigate a keystone that connects with individual response to chemicals, population dynamics, and ultimately ecosystem influences.

}, issn = {1520-5851}, doi = {10.1021/acs.est.8b00569}, author = {Ma, Zhiyuan and Peng, Hui and Jin, Yaru and Zhang, Xianming and Xie, Xianyi and Jian, Kang and Liu, Hongling and Su, Guanyong and Tang, Song and Yu, Hongxia} } @article {89, title = {A rapid and sensitive fluorometric method for determination of aldehyde oxidase activity.}, journal = {Toxicol Appl Pharmacol}, volume = {341}, year = {2018}, month = {2018 02 15}, pages = {30-37}, abstract = {

Previous research has characterized the important role of aldehyde oxidases (AOX) in biotransformation of N-heterocyclic therapeutic drugs and environmental contaminants in mammals. Research pertaining to AOX activity in non-mammalian vertebrates, however, is scarce, despite its biological role as a potentially important metabolic pathway for xenobiotics. One of the limiting factors of research on AOX is that available photometric methods are relatively insensitive, limited in throughput, and prone to cross-reactivity from other enzymes. Therefore, this study aimed to develop a novel and improved fluorometric AOX assay. This assay is based on the conversion of the exogenous aldehyde substrate 4-(dimethyl)amino cinnamaldehyde to its corresponding fluorescent acid by AOX, and was evaluated using partially purified hepatic cytosol from rat, human, and rainbow trout. Purification of native cytosol by heat treatment and ammonium sulfate precipitation resulted in increased specific activity of AOX. Michaelis-Menten kinetic parameters (Kand V) were comparable to values previously generated by photometric methods. Furthermore, effects of the inhibitor hydralazine on AOX activity revealed half maximal inhibitory concentrations comparable to those generated using conventional methods. Product identity was confirmed by liquid chromatography and mass spectrometry. In summary, this study successfully developed a rapid and sensitive assay for determination of AOX activity in across different vertebrate species that is 4- to 10-fold more sensitive compared to conventional absorbance-based methods. It can be applied in environmental, toxicological, and pharmacological studies relating to identification of AOX substrates, as well as the induction of AOX expression through drugs and environmental contaminants.

}, keywords = {Aldehyde Oxidase, Animals, Chromatography, Liquid, Dose-Response Relationship, Drug, Enzyme Activation, Enzyme Inhibitors, Fluorometry, Humans, Hydralazine, Mass Spectrometry, Oncorhynchus mykiss, Rats, Time Factors}, issn = {1096-0333}, doi = {10.1016/j.taap.2018.01.006}, author = {Apenova, Nancy and Peng, Hui and Hecker, Markus and Brinkmann, Markus} } @article {88, title = {Simultaneous determination of (N-ethyl perfluorooctanesulfonamido ethanol)-based phosphate diester and triester and their biotransformation to perfluorooctanesulfonate in freshwater sediments.}, journal = {Environ Pollut}, volume = {234}, year = {2018}, month = {2018 Mar}, pages = {821-829}, abstract = {

While (N-ethyl perfluorooctanesulfonamido ethanol)-based phosphates (SAmPAPs) have been proposed as a group of perfluorooctanesulfonate (PFOS) precursors, investigation of their occurrence and fate has been limited to SAmPAP diester. In this study, SAmPAP diester and triester were simultaneously determined in freshwater sediment from Taihu Lake using a newly developed UPLC-MS/MS method, and their biotransformation to PFOS in lake sediment was investigated. SAmPAP diester and triester were detected in sediments with a detection frequency of 56\% and 88\%, and their mean concentrations were 0.24\ {\textpm}\ 0.11\ ng/g dry weight (dw) and 0.12\ {\textpm}\ 0.03\ ng/g dw, respectively. The SAmPAP diester/triester ratio in sediment was 1.1\ {\textpm}\ 4.2, much lower than that (6.7) observed in the technical product, and the positive correlation was found between the concentrations of SAmPAP diester and PFOS in sediments (r\ =\ 0.45, p\ =\ 0.01), suggesting that SAmPAP diester would be biotransformed to PFOS in the lake sediment. The microbial degradation test in the lake sediments further clarified that SAmPAP diester was biodegraded to PFOS, but SAmPAP triester was highly recalcitrant to microbial degradation. This study suggests that the occurrence of SAmPAP diester in freshwater lake sediments may be an important precursor of PFOS.

}, keywords = {Alkanesulfonic Acids, Bacteria, Biodegradation, Environmental, Biotransformation, China, Environmental Monitoring, Fluorocarbons, Geologic Sediments, Hydrocarbons, Fluorinated, Lakes, Organophosphates, Sulfonamides, Tandem Mass Spectrometry, Water Pollutants, Chemical}, issn = {1873-6424}, doi = {10.1016/j.envpol.2017.12.021}, author = {Zhang, Shiyi and Peng, Hui and Mu, Di and Zhao, Haoqi and Hu, Jianying} } @article {84, title = {Sono-chemical treatment of per- and poly-fluoroalkyl compounds in aqueous film-forming foams by use of a large-scale multi-transducer dual-frequency based acoustic reactor.}, journal = {Ultrason Sonochem}, volume = {45}, year = {2018}, month = {2018 Jul}, pages = {213-222}, abstract = {

Aqueous film-forming foams (AFFFs) contain a mixture of organic chemicals, including per- and poly-fluorinated, alkyl sulfonate substances (PFAS) (1-5\%, w/w). Some longer-chain PFAS can be toxic, moderately bioaccumulative and persistent in the environment. In the present work, decomposition of PFAS present in two commercially available AFFFs (ANSUL- and 3M-) was investigated using a sono-chemical reactor of volume 91 L. The reactor consists of 12 transducers with operating frequencies of 1 MHz or 500 kHz and total input power of 12 kW. Degradation of PFASs performed using various dilutions of AFFF revealed that release of F and SO ions was inversely proportional to initial pH of up to 4. Defluorination of ANSUL-AFFF resulted in an increase in the concentration of F released from 55.6 {\textpm} 0.3 {\textmu}M (500{\texttimes} dilution) to 58.6 {\textpm} 0.6 (25{\texttimes} dilution), while for 3M AFFF it increased from 19.9 {\textpm} 0.7 {\textmu}M (500{\texttimes} dilution) to 217.1 {\textpm} 2.4 {\textmu}M (25{\texttimes} dilution). Though amounts of F released were less for ANSUL-AFFF than for 3M-AFFF, there was a considerable increase in removal of TOC and release of SO present in ANSUL-AFFF. Approximately 90.5\% and 26.6\% reduction of perfluoroalkyl sulfonates (PFSA) and perfluoroalkyl carboxylates (PFCA) in 3M, respectively, and 38.4\% reduction of fluorotelomer sulfonates in ANSUL-AFFF were achieved in 13 h. Estimated costs of energy for the treatment of ANSUL-AFFF and 3M-AFFF at a 500{\texttimes} dilution were $0.015 {\textpm} 0.0001/L and $0.019 {\textpm} 0.0002/L, respectively.

}, issn = {1873-2828}, doi = {10.1016/j.ultsonch.2018.02.014}, author = {Gole, Vitthal L and Sierra-Alvarez, Reyes and Peng, Hui and Giesy, John P and Deymier, Pierre and Keswani, Manish} } @article {85, title = {Spatial and temporal trends in poly- and per-fluorinated compounds in the Laurentian Great Lakes Erie, Ontario and St. Clair.}, journal = {Environ Pollut}, volume = {237}, year = {2018}, month = {2018 Jun}, pages = {396-405}, abstract = {

The temporal and spatial trends in sediment of 22 poly- and perfluorinated (PFAS) compounds were investigated in the southern Great Lakes Erie and Ontario as well as Lake St. Clair. Surface concentrations measured by Ponar grab samples indicated a trend for greater concentrations near to urban sites. Mean concentrations ∑PFAS were 15.6, 18.2 and 19 ng g dm for Lakes St. Clair, Erie and Ontario, respectively. Perfluoro-n-butanoic acid (PFBA) and Perfluoro-n-hexanoic acid (PFHxA) were frequently determined in surface sediment and upper core samples indicating a shift in use patterns. Where PFBA was identified it was at relatively great concentrations typically \>10 ng g dm. However as PFBA and PFHxA are less likely to bind to sediment they may be indicative of pore water concentrations Sedimentation rates between Lake Erie and Lake Ontario differ greatly with greater rates observed in Lake Erie. In Lake Ontario, in general concentrations of PFAS observed in core samples closely follow the increase in use along with an observable change due to regulation implementation in the 1970s for water protection. However some of the more water soluble PFAS were observed in deeper core layers than the time of production could account for, indicating potential diffusion within the sediment. Given the greater sedimentation rates in Lake Erie, it was hoped to observe in greater resolution changes since the mid-1990s. However, though some decrease was observed at some locations the results are not clear. Many cores in Lake Erie had clearly observable gas voids, indicative of gas ebullition activity due to biogenic production, there were also observable mussel beds that could indicate mixing by bioturbation of core layers.

}, keywords = {Environmental Monitoring, Fluorocarbons, Great Lakes Region, Lakes, Ontario, Water Pollutants, Chemical, Water Pollution, Chemical}, issn = {1873-6424}, doi = {10.1016/j.envpol.2018.02.013}, author = {Codling, Garry and Sturchio, Neil C and Rockne, Karl J and Li, An and Peng, H and Tse, Timothy J and Jones, Paul D and Giesy, John P} } @article {91, title = {Detection, Occurrence, and Fate of Fluorotelomer Alcohols in Municipal Wastewater Treatment Plants.}, journal = {Environ Sci Technol}, volume = {51}, year = {2017}, month = {2017 Aug 15}, pages = {8953-8961}, abstract = {

Fluorotelomer alcohols (FTOHs) are the most well-known precursors of perfluoroalkyl carboxylic acids (PFCAs), but limited information is available on their occurrence and fate in municipal wastewater treatment plants (WWTPs). The occurrence of FTOHs was investigated in influent, secondary effluent, and sludge of 12 municipal WWTPs in nine cities of China. FTOHs were detected in all WWTPs, and 8:2 FTOH was the predominant congener, with concentrations of 2.10-11.0 ng/L, 3.05-12.4 ng/L, and 0.36-1.91 ng/g dry weight in the influent, secondary effluent, and sludge, respectively. Relatively high proportions of long-chain FTOHs (C) were mainly detected in sludge samples. The mass balance of FTOHs and PFCAs in one of the WWTPs with an anaerobic-anoxic-oxic process was further explored. The decrease of mass loads was observed for 4:2 FTOH (mass change percentage: 21 {\textpm} 3.3\%), 8:2 FTOH (22 {\textpm} 1.5\%), and 10:2 FTOH (29 {\textpm} 7.3\%) through aerobic treatment, while the increase of mass loads was observed for 12 PFCAs from 18 {\textpm} 16\% (perfluorononanoic acid) to 165 {\textpm} 15\% (perfluorobutyric acid)), suggesting the potential biotransformation of FTOHs to PFCAs in the aerobic unit. This work provides the first report on the occurrence of FTOHs in sludge samples of municipal WWTPs and their mass balance and highlights a new emission route to environment via WWTPs.

}, keywords = {Alcohols, China, Cities, Fluorocarbons, Sewage, Waste Water}, issn = {1520-5851}, doi = {10.1021/acs.est.7b00315}, author = {Chen, Hongrui and Peng, Hui and Yang, Min and Hu, Jianying and Zhang, Yu} } @article {92, title = {Hydroxylated 2-Ethylhexyl tetrabromobenzoate isomers in house dust and their agonistic potencies with several nuclear receptors.}, journal = {Environ Pollut}, volume = {227}, year = {2017}, month = {2017 Aug}, pages = {578-586}, abstract = {

In the current study, by combining ultra-high resolution (UHR) MS spectra, MS spectra, and derivatization, three hydroxylated isomers of 2-ethylhexyl tetrabromobenzoate (OH-TBB) were identified in Firemaster 550 and BZ-54 technical products. Also, a new LC-UHRMS method, using atmospheric pressure chemical ionization (APCI), was developed for simultaneous analysis of OH-TBB, TBB, hydroxylated bis(2-ethylhexyl)-tetrabromophthalate (OH-TBPH) and TBPH in 23 samples of dust collected from houses in Saskatoon, SK, Canada. OH-TBBs were detected in 91\% of samples, with a geometric mean concentration of 0.21\ ng/g, which was slightly less than those of OH-TBPH (0.35\ ng/g). TBB was detected in 100\% of samples of dust with a geometric mean concentration of 992\ ng/g. Significant (p\ \<\ 0.001) log-linear relationships between concentrations of OH-TBBs, TBB, or OH-TBPHs and TBPH in dust support the hypothesis of a common source of these compounds. OH-TBBs were found to be strong agonists of peroxisome proliferator-activated receptor gamma (PPARγ) and weaker agonists of the estrogen receptor (ER), but no agonistic potencies was observed with the androgen receptor (AR). Occurrence of OH-TBBs in technical products and house dust, together with their relatively strong PPARγ potencies, indicated their potential risk to health of humans.

}, keywords = {Air Pollution, Indoor, Bromobenzoates, Canada, Dust, Environmental Monitoring, Flame Retardants, Halogenated Diphenyl Ethers, Humans}, issn = {1873-6424}, doi = {10.1016/j.envpol.2017.04.094}, author = {Peng, Hui and Sun, Jianxian and Saunders, David M V and Codling, Garry and Wiseman, Steve and Jones, Paul D and Giesy, John P} } @article {93, title = {Identification of Chemicals that Cause Oxidative Stress in Oil Sands Process-Affected Water.}, journal = {Environ Sci Technol}, volume = {51}, year = {2017}, month = {2017 Aug 01}, pages = {8773-8781}, abstract = {

Oil sands process-affected water (OSPW) has been reported to cause oxidative stress in organisms, yet the causative agents remain unknown. In this study, a high-throughput in vitro Nrf2 reporter system was used, to determine chemicals in OSPW that cause oxidative stress. Five fractions, with increasing polarity, of the dissolved organic phase of OSPW were generated by use of solid phase extraction cartridges. The greatest response of Nrf2 was elicited by F2 (2.7 {\textpm} 0.1-fold), consistent with greater hydroperoxidation of lipids in embryos of Japanese medaka (Oryzias latipes) exposed to F2. Classic naphthenic acids were mainly eluted in F1, and should not be causative chemicals. When F2 was fractionated into 60 subfractions by use of HPLC, significant activation of Nrf2 was observed in three grouped fractions: F2.8 (1.30 {\textpm} 0.01-fold), F2.16 (1.34 {\textpm} 0.05-fold), and F2.25 (1.28 {\textpm} 0.15-fold). 54 compounds were predicted to be potential chemicals causing Nrf2 response, predominated by SO and O species. By use of high-resolution MS spectra, these SO and O species were identified as hydroxylated aldehydes. This study demonstrated that polyoxygenated chemicals, rather than classic NAs, were the major chemicals responsible for oxidative stress in the aqueous phase of OSPW.

}, keywords = {Animals, Carboxylic Acids, Oil and Gas Fields, Oryzias, Oxidative Stress, Water, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/acs.est.7b01987}, author = {Sun, Jianxian and Peng, Hui* and Alharbi, Hattan A and Jones, Paul D and Giesy, John P and Wiseman, Steve B} } @article {90, title = {Mass spectrometry methods to study protein-metabolite interactions.}, journal = {Expert Opin Drug Discov}, volume = {12}, year = {2017}, month = {2017 12}, pages = {1271-1280}, abstract = {

INTRODUCTION: To ​​​​understand and manipulate biochemical processes and signaling pathways, the knowledge of endogenous protein-metabolite interactions would be extremely helpful. Recent developments in precision mass spectrometry, high-throughput proteomics and sensitive metabolomic profiling are beginning to converge on a possible solution, heralding a new era of global metabolome-proteome {\textquoteright}interactome{\textquoteright} studies that promise to change biomedical research and drug discovery. Areas covered: Here, we review innovative mass spectrometry-based methods and recent pioneering studies aimed at elucidating the physical associations of small molecule ligands with cellular proteins. The technologies covered belong to two main categories: tag-based and tag-free methods. We emphasize the latter in this review, and outline promising experimental workflows and key data analysis considerations involved. Expert opinion: Recent ground-breaking advances in chemical-proteomics technology and allied computational methods now make the global detection of protein-ligand engagement an increasingly attractive research problem. Despite ongoing challenges, rapid progress in the field is expected these coming next few years, leading to a refreshed systems biology research paradigm and much needed new opportunities for improving sparse drug discovery pipelines.

}, keywords = {Biomedical Research, Drug Discovery, High-Throughput Screening Assays, Humans, Ligands, Mass Spectrometry, Metabolome, Metabolomics, Proteins, Proteome, Proteomics, Systems Biology}, issn = {1746-045X}, doi = {10.1080/17460441.2017.1378178}, author = {Guo, Hongbo and Peng, Hui and Emili, Andrew} } @article {94, title = {Response to Comment on "Mutagenic Azo Dyes, Rather than Flame Retardants, are the Predominant Brominated Compounds in House Dust".}, journal = {Environ Sci Technol}, volume = {51}, year = {2017}, month = {2017 03 21}, pages = {3591-3592}, keywords = {Air Pollution, Indoor, Azo Compounds, Dust, Environmental Exposure, Flame Retardants, Halogenated Diphenyl Ethers, Hydrocarbons, Brominated, Mutagens}, issn = {1520-5851}, doi = {10.1021/acs.est.7b00675}, author = {Peng, Hui and Saunders, David M V and Jones, Paul D and Giesy, John P} } @article {100, title = {Combined Transcriptomic and Proteomic Approach to Identify Toxicity Pathways in Early Life Stages of Japanese Medaka (Oryzias latipes) Exposed to 1,2,5,6-Tetrabromocyclooctane (TBCO).}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 07 19}, pages = {7781-90}, abstract = {

Currently, the novel brominated flame retardant 1,2,5,6-tetrabromocyclooctane (TBCO) is considered a potential replacement for hexabromocyclododecane (HBCD). Therefore, use of TBCO could increase in the near future. To assess potential toxicological risks to aquatic organisms, embryos of Japanese medaka (Oryzias latipes) were exposed to 10, 100, or 1000 μg/L TBCO from 2 h postfertilization until 1 day post-hatch. TBCO accumulated in embryos in the order of 0.43-1.3 {\texttimes} 10(4)-fold, and the rate constant of accumulation was 1.7-1.8 per day. The number of days to hatch and the hatching success of embryos exposed to the medium and the greatest concentrations of TBCO were impaired. Responses of the transcriptome (RNA-seq) and proteome were characterized in embryos exposed to 100 μg/L TBCO because this was the least concentration of TBCO that caused an effect on hatching. Consistent with effects on hatching, proteins whose abundances were reduced by exposure to TBCO were enriched in embryo development and hatching pathways. Also, on the basis of the responses of transcriptome and proteome, it was predicted that TBCO might impair vision and contraction of cardiac muscle, respectively, and these effects were confirmed by targeted bioassays. This study provided a comprehensive understanding of effects of TBCO on medaka at early life stages and illustrated the power of "omics" to explain and predict phenotypic responses to chemicals.

}, keywords = {Animals, Oryzias, Proteomics, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/acs.est.6b01249}, author = {Sun, Jianxian and Tang, Song and Peng, Hui* and Saunders, David M V and Doering, Jon A and Hecker, Markus and Jones, Paul D and Giesy, John P and Wiseman, Steve} } @article {101, title = {High Conservation in Transcriptomic and Proteomic Response of White Sturgeon to Equipotent Concentrations of 2,3,7,8-TCDD, PCB 77, and Benzo[a]pyrene.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 05 03}, pages = {4826-35}, abstract = {

Adverse effects associated with exposure to dioxin-like compounds (DLCs) are mediated primarily through activation of the aryl hydrocarbon receptor (AHR). However, little is known about the cascades of events that link activation of the AHR to apical adverse effects. Therefore, this study used high-throughput, next-generation molecular tools to investigate similarities and differences in whole transcriptome and whole proteome responses to equipotent concentrations of three agonists of the AHR, 2,3,7,8-TCDD, PCB 77, and benzo[a]pyrene, in livers of a nonmodel fish, the white sturgeon (Acipenser transmontanus). A total of 926 and 658 unique transcripts were up- and down-regulated, respectively, by one or more of the three chemicals. Of the transcripts shared by responses to all three chemicals, 85\% of up-regulated transcripts and 75\% of down-regulated transcripts had the same magnitude of response. A total of 290 and 110 unique proteins were up- and down-regulated, respectively, by one or more of the three chemicals. Of the proteins shared by responses to all three chemicals, 70\% of up-regulated proteins and 48\% of down-regulated proteins had the same magnitude of response. Among treatments there was 68\% similarity between the global transcriptome and global proteome. Pathway analysis revealed that perturbed physiological processes were indistinguishable between equipotent concentrations of the three chemicals. The results of this study contribute toward more completely describing adverse outcome pathways associated with activation of the AHR.

}, keywords = {Animals, Benzo(a)pyrene, Dioxins, Fishes, Polychlorinated Dibenzodioxins, Proteomics}, issn = {1520-5851}, doi = {10.1021/acs.est.6b00490}, author = {Doering, Jon A and Tang, Song and Peng, Hui and Eisner, Bryanna K and Sun, Jianxian and Giesy, John P and Wiseman, Steve and Hecker, Markus} } @article {95, title = {Mutagenic Azo Dyes, Rather Than Flame Retardants, Are the Predominant Brominated Compounds in House Dust.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 12 06}, pages = {12669-12677}, abstract = {

Characterization of toxicological profiles by use of traditional targeted strategies might underestimate the risk of environmental mixtures. Unbiased identification of prioritized compounds provides a promising strategy for meeting regulatory needs. In this study, untargeted screening of brominated compounds in house dust was conducted using a data-independent precursor isolation and characteristic fragment (DIPIC-Frag) approach, which used data-independent acquisition (DIA) and a chemometric strategy to detect peaks and align precursor ions. A total of 1008 brominated compound peaks were identified in 23 house dust samples. Precursor ions and formulas were identified for 738 (73\%) of the brominated compounds. A correlation matrix was used to cluster brominated compounds; three large groups were found for the 140 high-abundance brominated compounds, and only 24 (17\%) of these compounds were previously known flame retardants. The predominant class of unknown brominated compounds was predicted to consist of nitrogen-containing compounds. Following further validation by authentic standards, these compounds (56\%) were determined to be novel brominated azo dyes. The mutagenicity of one major component was investigated, and mutagenicity was observed at environmentally relevant concentrations. Results of this study demonstrated the existence of numerous unknown brominated compounds in house dust, with mutagenic azo dyes unexpectedly being identified as the predominant compounds.

}, keywords = {Azo Compounds, Dust, Flame Retardants, Halogenated Diphenyl Ethers, Hydrocarbons, Brominated, Mutagens}, issn = {1520-5851}, doi = {10.1021/acs.est.6b03954}, author = {Peng, Hui and Saunders, David M V and Sun, Jianxian and Jones, Paul D and Wong, Chris K C and Liu, Hongling and Giesy, John P} } @article {99, title = {Peroxisome Proliferator-Activated Receptor γ is a Sensitive Target for Oil Sands Process-Affected Water: Effects on Adipogenesis and Identification of Ligands.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 07 19}, pages = {7816-24}, abstract = {

Identification of toxic components of complex mixtures is a challenge. Here, oil sands process-affected water (OSPW) was used as a case study to identify those toxic components with a known protein target. Organic chemicals in OSPW exhibited dose-dependent activation of peroxisome proliferator-activated receptor γ (PPARγ) at concentrations less than those currently in the environment (0.025{\texttimes} equivalent of full-strength OSPW), by use of a luciferase reporter gene assay. Activation of PPARγ-mediated adipogenesis by OSPW was confirmed in 3T3L1 preadipocytes, as evidenced by accumulation of lipids and up-regulation of AP2, LPL, and PPARγ gene expression after exposure to polar fractions of OSPW. Unexpectedly, the nonpolar fractions of OSPW inhibited differentiation of preadipocytes via activation of the Wnt signaling pathway. Organic chemicals in OSPW that were ligands of PPARγ were identified by use of a pull-down system combined with untargeted chemical analysis (PUCA), with a recombinant PPARγ protein. Thirty ligands of PPARγ were identified by use of the PUCA assay. High resolution MS(1) and MS(2) spectra were combined to predict the formulas or structures of a subset of ligands, and polyoxygenated or heteroatomic chemicals, especially hydroxylated carboxylic/sulfonic acids, were the major ligands of PPARγ.

}, keywords = {Adipogenesis, Ligands, Oil and Gas Fields, PPAR gamma, Water}, issn = {1520-5851}, doi = {10.1021/acs.est.6b01890}, author = {Peng, Hui and Sun, Jianxian and Alharbi, Hattan A and Jones, Paul D and Giesy, John P and Wiseman, Steve} } @article {104, title = {p,p{\textquoteright}-DDE Induces Gonadal Intersex in Japanese Medaka (Oryzias latipes) at Environmentally Relevant Concentrations: Comparison with o,p{\textquoteright}-DDT.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 Jan 05}, pages = {462-9}, abstract = {

Previous studies have reported high body burdens of dichlorodiphenyltrichloroethane (DDT) and its metabolites in wild fishes worldwide. This study evaluated the adverse effects of 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p{\textquoteright}-DDE) and o,p{\textquoteright}-DDT on gonadal development and reproduction by exposing transgenic Japanese medaka (Oryzias latipes) from hatch for 100 days. While both p,p{\textquoteright}-DDE and o,p{\textquoteright}-DDT induced intersex in male medaka, the lowest observable effective concentration (LOEC) of o,p{\textquoteright}-DDT was 57.7 ng/g ww, about 5-fold lower than that (272 ng/g ww) of p,p{\textquoteright}-DDE. Since LOECs of both chemicals were comparable to the body concentrations in wild fish, DDT contamination would likely contribute to the occurrence of intersex observed in wild fish. Exposure to o,p{\textquoteright}-DDT resulted in much higher expression of vitellogenin in liver of males than p,p{\textquoteright}-DDE, accordant with the higher potency of o,p{\textquoteright}-DDT than p,p{\textquoteright}-DDE to induce intersex. This phenomenon could be partly explained by the significantly elevated levels of 17β-estradiol in plasma of males exposed to o,p{\textquoteright}-DDT, in addition to its estrogenic activity via the estrogen receptor. Significantly lower fertilization (p = 0.006) and hatchability (p = 0.019) were observed in the 13 intersex males. This study for the first time demonstrated the induction of intersex and reproductive effects of p,p{\textquoteright}-DDE and o,p{\textquoteright}-DDT at environmentally relevant concentrations.

}, keywords = {Animals, DDT, Dichlorodiphenyl Dichloroethylene, Disorders of Sex Development, Estradiol, Gonads, Male, Oryzias, Vitellogenins, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/acs.est.5b05042}, author = {Sun, Jianxian and Wang, Chen and Peng, Hui and Zheng, Guomao and Zhang, Shiyi and Hu, Jianying} } @article {96, title = {Sonochemical degradation of perfluorinated chemicals in aqueous film-forming foams.}, journal = {J Hazard Mater}, volume = {317}, year = {2016}, month = {2016 Nov 05}, pages = {275-283}, abstract = {

Aqueous film-forming foams (AFFFs) are complex mixtures containing 1-5\% w/w fluorocarbons (FCs). Here, we have investigated degradation of two commercial AFFF formulations, 3M and Ansul, using sound field at 500kHz and 1MHz, with varying initial concentrations ranging from 200 to 930{\texttimes} dilution. The foams were readily degraded by 1MHz, with percentage of defluorination ranging from 11.1{\textpm}1.4\% (200{\texttimes} dilution of 3M) to 47.1{\textpm}5.8\% (500{\texttimes} dilution of Ansul). Removal of total organic carbon (TOC) ranged from 16.0{\textpm}1.4\% (200{\texttimes} dilution Ansul) to 39.0{\textpm}7.2\% (500{\texttimes} dilution Ansul). Degradation of AFFF was affected by sound frequency with rates of defluorination 10-fold greater when the frequency was 1MHz than when it was 500kHz. Mineralization of TOC was 1.5- to 3.0-fold greater under 1MHz than 500kHz. Rate of fluoride release was 60\% greater for the greatest initial concentration of FC in Ansul compared to the least initial concentration. While the rate of mineralization of AFFF was directly proportional to the initial concentration of Ansul, that was not the case for 3M, where the rates of mineralization were approximately the same for all three initial concentrations. Results of the study demonstrate that sonolysis is a promising technology to effectively treat AFFFs.

}, issn = {1873-3336}, doi = {10.1016/j.jhazmat.2016.05.078}, author = {Rodriguez-Freire, Lucia and Abad-Fern{\'a}ndez, Nerea and Sierra-Alvarez, Reyes and Hoppe-Jones, Christiane and Peng, Hui and Giesy, John P and Snyder, Shane and Keswani, Manish} } @article {102, title = {Ubiquitous Occurrence of Fluorotelomer Alcohols in Eco-Friendly Paper-Made Food-Contact Materials and Their Implication for Human Exposure.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 Jan 19}, pages = {942-50}, abstract = {

The occurrence of fluorotelomer alcohols (FTOHs) was investigated in 94 food-contact materials (FCMs). We detected 6:2 FTOH (\<0.60-1110 ng/g), 8:2 FTOH (\<0.40-8490 ng/g), and 10:2 FTOH (\<0.02-9350 ng/g) in most FCM samples, and four longer-chain C14-20 FTOHs were, for the first time, identified in FCMs with relatively high concentrations (\<0.02-8450 ng/g for 12:2 FTOH, \<0.02-1640 ng/g for 14:2 FTOH, \<0.02-372 ng/g for 16:2 FTOH, and \<0.02-130 ng/g for 18:2 FTOH). There were three typical profiles of FTOHs that were dominated by 6:2 FTOH (95.6 {\textpm} 8.1\% in 9 FCMs), 8:2 FTOH (50.9 {\textpm} 20.8\% in 22 FCMs), and 10:2 FTOH (44.5 {\textpm} 20.9\% in 30 FCMs), indicating the congener-specific usage of FTOHs for different commercial purposes. All nine detectable FCMs produced in the United States were dominated by 6:2 FTOH, which was significantly different from those produced in China. The median concentration of total FTOHs in eco-friendly paper tableware was 2990 ng/g, which was lower than in popcorn bags (18 200 ng/g) but much higher than other FCMs (\<0.55-38.7 ng/g). FTOHs could migrate from paper bowls, with migration efficiencies of 0.004-0.24\% into water, 0.004-0.24\% into 10\% ethanol, 0.009-2.79\% into 30\% ethanol, 0.06-13.0\% into 50\% ethanol (v/v) simulants, and 0.04-2.28\% into oil. Migration efficiencies decreased with increasing carbon chain lengths of FTOHs.

}, keywords = {Alcohols, Biodegradation, Environmental, Fluorocarbons, Food Contamination, Food Packaging, Humans, Paper}, issn = {1520-5851}, doi = {10.1021/acs.est.5b03806}, author = {Yuan, Guanxiang and Peng, Hui and Huang, Chong and Hu, Jianying} } @article {97, title = {An Unbiased Chemical Proteomics Method Identifies FabI as the Primary Target of 6-OH-BDE-47.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 Oct 18}, pages = {11329-11336}, abstract = {

Determination of the physical interactions of environmental chemicals with cellular proteins is important for characterizing biological and toxic mechanism of action. Yet despite the discovery of numerous bioactive natural brominated compounds, such as hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their corresponding protein targets remain largely unclear. Here, we reported a systematic and unbiased chemical proteomics assay (Target Identification by Ligand Stabilization, TILS) for target identification of bioactive molecules based on monitoring ligand-induced thermal stabilization. We first validated the broad applicability of this approach by identifying both known and unexpected proteins bound by diverse compounds (anticancer drugs, antibiotics). We then applied TILS to identify the bacterial target of 6-OH-BDE-47 as enoyl-acyl carrier protein reductase (FabI), an essential and widely conserved enzyme. Using affinity pull-down and in vitro enzymatic assays, we confirmed the potent antibacterial activity of 6-OH-BDE-47 occurs via direct binding and inhibition of FabI. Conversely, overexpression of FabI rescued the growth inhibition of Escherichia coli by 6-OH-BDE-47, validating it as the primary in vivo target. This study documents a chemical proteomics strategy for identifying the physical and functional targets of small molecules, and its potential high-throughput application to investigate the modes-of-action of environmental compounds.

}, issn = {1520-5851}, doi = {10.1021/acs.est.6b03541}, author = {Peng, Hui and Guo, Hongbo and Pogoutse, Oxana and Wan, Cuihong and Hu, Lucas Z and Ni, Zuyao and Emili, Andrew} } @article {103, title = {Untargeted Screening and Distribution of Organo-Bromine Compounds in Sediments of Lake Michigan.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 Jan 05}, pages = {321-30}, abstract = {

Previously unreported natural and synthetic organo-bromine compounds (NSOBCs) have been found to contribute more than 99\% of total organic bromine (TOB) in environmental matrices. We recently developed a novel untargeted method (data-independent precursor isolation and characteristic fragment, DIPIC-Frag) and identified \~{}2000 NSOBCs in two sediments from Lake Michigan. In this study, this method was used to investigate the distributions of these NSOBCs in 23 surficial samples and 24 segments of a sediment core from Lake Michigan. NSOBCs were detected in all 23 surficial samples and exhibited 10- to 100-fold variations in peak abundance among locations. The pattern of distributions of NSOBCs was correlated with depth of the water column (r(2) = 0.61, p \< 0.001). Hierarchical cluster analysis showed that sediments in close proximity exhibited similar profiles of NSOBCs. Distributions of NSOBCs in 24 segments of a sediment core dated from 1766 to 2008 were investigated, and samples from similar depths exhibited similar profiles of NSOBCs. NSOBCs were grouped into four clusters (soft-cluster analysis) with different temporal trends of abundances. 515 and 768 of the NSOBCs were grouped into cluster 1 and cluster 3 with increasing temporal trends, especially since 1950, indicating that abundances of these compounds might have been affected by human activities.

}, keywords = {Bromine Compounds, Environmental Monitoring, Geologic Sediments, Halogenated Diphenyl Ethers, Hydrocarbons, Brominated, Lakes, Michigan, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/acs.est.5b04709}, author = {Peng, Hui and Chen, Chunli and Cantin, Jenna and Saunders, David M V and Sun, Jianxian and Tang, Song and Codling, Garry and Hecker, Markus and Wiseman, Steve and Jones, Paul D and Li, An and Rockne, Karl J and Sturchio, Neil C and Giesy, John P} } @article {98, title = {Untargeted Screening and Distribution of Organo-Iodine Compounds in Sediments from Lake Michigan and the Arctic Ocean.}, journal = {Environ Sci Technol}, volume = {50}, year = {2016}, month = {2016 09 20}, pages = {10097-105}, abstract = {

The majority of halogenated organic compounds present in the environment remain unidentified. To address this data gap, we recently developed an untargeted method (data-independent precursor isolation and characteristic fragment; DIPIC-Frag) for identification of unknown organo-bromine compounds. In this study, the method was adapted to enable untargeted screening of natural and synthetic organo-iodine compounds (NSOICs) in sediments. A total of 4,238 NSOIC peaks were detected in sediments from Lake Michigan. Precursor ions and formulas were determined for 2,991 (71\%) of the NSOIC peaks. These compounds exhibited variations in abundances (\<10(3) to \~{}10(7)), m/z values (206.9304-996.9474), retention times (1.0-29.7 min), and number of iodine atoms (1-4). Hierarchical cluster analysis showed that sediments in closer proximity exhibited similar profiles of NSOICs. NSOICs were screened in 10 samples of sediment from the Arctic Ocean to compare the profiles of NSOICs between freshwater and marine sediments. A total of 3,168 NSOIC peaks were detected, and profiles of NSOICs in marine sediments were clearly distinct from Lake Michigan. The coexistence of brominated and iodinated analogues indicated that some NSOICs are of natural origin. Different ratios of abundances of iodinated compounds to brominated analogues were observed and proposed as a marker to distinguish sources of NSOICs.

}, keywords = {Geologic Sediments, Iodine Compounds, Lakes, Michigan, Oceans and Seas, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/acs.est.6b03221}, author = {Peng, Hui and Chen, Chunli and Cantin, Jenna and Saunders, David M V and Sun, Jianxian and Tang, Song and Codling, Garry and Hecker, Markus and Wiseman, Steve and Jones, Paul D and Li, An and Rockne, Karl J and Sturchio, Neil C and Cai, Minghong and Giesy, John P} } @article {107, title = {Detection, identification, and quantification of hydroxylated bis(2-ethylhexyl)-tetrabromophthalate isomers in house dust.}, journal = {Environ Sci Technol}, volume = {49}, year = {2015}, month = {2015 Mar 03}, pages = {2999-3006}, abstract = {

Ultra-High Resolution LC/mass spectrometry (LC-UHRMS; Thermo Fisher Q-Exactive) was used to identify two novel isomers of hydroxylated bis(2-ethylhexyl)-tetrabromophthalate (OH-TBPH) which were unexpectedly observed in a commercial standard of TBPH. By combining ultra-high resolution (UHR) mass spectra (MS(1)), mass errors to theoretical [TBPH-Br+O](-) were 2.1 and 1.0 ppm for the two isomers, UHR-MS(2) spectra and NMR analysis; the structures of the two compounds were identified as hydroxylated TBPH with a hydroxyl group on the aromatic ring. Relatively great proportions of the two isomers of OH-TBPH were detected in two technical products, Firemaster 550 (FM-550; 0.1\% and 6.2\%, respectively) and Firemaster BZ 54 (BZ-54; 0.1\% and 7.9\%), compared to a commercial standard (0.4\% and 0.9\%). To simultaneously analyze OH-TBPH isomers and TBPH in samples of dust, a method based on LC-UHRMS was developed to quantify the two compounds, using negative and positive ion modes, respectively. The instrumental limit of detection for TBPH was 0.01 μg/L, which was 200-300 times better than traditional methods (2.5 μg/L) based on gas chromatography-mass spectrometry. The analytical method combined with a Florisil cleanup was successfully applied to analyze TBPH and OH-TBPH in 23 indoor dust samples from Saskatoon, Saskatchewan, Canada. Two OH-TBPH isomers, OH-TBPH1 and OH-TBPH2, were detected in 52\% and 91\% of dust samples, respectively. Concentrations of OH-TBPH2 (0.35 {\textpm} 1.0 ng/g) were 10-fold greater than those of OH-TBPH1 (0.04 {\textpm} 0.88 ng/g) in dust, which was similar to profiles in FM-550 and BZ-54. TBPH was also detected in 100\% of dust samples with a mean concentration of 733 {\textpm} 0.87 ng/g. A significant (p \< 0.001) log-linear relationship was observed between TBPH and OH-TBPH isomers, further supporting the hypothesis of a common source of emission. Relatively small proportions of OH-TBPH isomers were detected in dust (0.01\% {\textpm} 0.67 OH-TBPH1 and 0.1\% {\textpm} 0.60 OH-TBPH2), which were significantly less than those in technical products (p \< 0.001). This result indicated different environmental behaviors of OH-TBPH and TBPH. Detection of isomers of OH-TBPH is important, since compounds with phenolic groups have often shown relatively greater toxicities than nonhydroxylated analogues. Further study is warranted to clarify the environmental behaviors and potential toxicities of OH-TBPH isomers.

}, keywords = {Chromatography, Liquid, Dust, Flame Retardants, Limit of Detection, Mass Spectrometry, Phthalic Acids}, issn = {1520-5851}, doi = {10.1021/es505743d}, author = {Peng, Hui and Saunders, David M V and Sun, Jianxian and Codling, Garry and Wiseman, Steve and Jones, Paul D and Giesy, John P} } @article {108, title = {Isomer-specific trophic transfer of perfluorocarboxylic acids in the marine food web of Liaodong Bay, North China.}, journal = {Environ Sci Technol}, volume = {49}, year = {2015}, month = {2015 Feb 03}, pages = {1453-61}, abstract = {

Trophic transfers of perfluorocarboxylic acids (PFCAs) have been well studied in aquatic food webs; however, most studies examined PFCAs as single compounds without differentiating isomers. In this study, an in-port derivatization GC-MS method was used to determine PFCA (perfluorooctanoic acid, PFOA; perfluorononanoic acid, PFNA; perfluorodecanoate acid, PFDA; perfluoroundecanoate acid, PFUnDA; perfluorododecanoate acid, PFDoDA; perfluorotridecanoate acid, PFTriDA, and perfluorotetradecanoate acid, PFTeDA) structural isomers in 11 marine species including benthic invertebrates, fishes, and gulls collected in November 2006 from Liaodong Bay in China. The total concentrations of linear PFCAs were 0.35-1.10, 0.93-2.61, and 2.13-2.69 ng/g ww, and the corresponding percentages of branched PFCAs to linear PFCAs were 6.6-15.5\%, 4.2-9.9\%, and 4.5-6.0\% in invertebrates, fishes, and birds, respectively. Except for linear PFOA, significant positive relationships were found between the concentrations of all the target linear PFCAs and trophic levels, and the trophic magnification factors (TMFs) ranged from 1.90 to 4.88. Positive correlations between the concentrations of branched PFCAs isomers and trophic levels were also observed but were without statistical significance. The relatively high biomagnification of linear isomers of PFCAs would lead to low percentages of branched PFCAs to total PFCAs in organisms at high trophic levels. This study for the first time clarified isomer-specific trophic transfers of PFCAs in a marine food web.

}, keywords = {Animals, Bays, Birds, Carboxylic Acids, China, Environmental Monitoring, Fishes, Fluorocarbons, Food Chain, Invertebrates, Isomerism, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/es504445x}, author = {Zhang, Zhong and Peng, Hui and Wan, Yi and Hu, Jianying} } @article {106, title = {Levels of Phthalate Metabolites in Urine of Pregnant Women and Risk of Clinical Pregnancy Loss.}, journal = {Environ Sci Technol}, volume = {49}, year = {2015}, month = {2015 Sep 01}, pages = {10651-7}, abstract = {

Toxicological studies have shown that phthalate esters (PAEs), a class of widely used and environmentally prevalent chemicals, can increase the abortion rate in animals, but epidemiological evidence is scarce. This study aimed to explore the relationship between the urinary concentration of phthalate metabolites and the risk of clinical pregnancy loss. A total of 132 women who underwent clinical pregnancy loss (cases) and 172 healthy pregnant women (controls) were recruited from Beijing, China. Eight phthalate metabolites in urine were determined by ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Five phthalate metabolites, monomethyl phthalate (MMP), monoethyl phthalate (MEP), monoisobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), and mono(2-ethlyhexyl) phthalate (MEHP), were detected in at least 95\% of the urine samples, with the highest median concentration of 51.0 μg/g of creatinine for MnBP of all participants. The differences in urinary concentrations of phthalate metabolites between cases and controls were evaluated using the Mann-Whitney U test. The concentrations of MEP (median of 18.7 μg/g of creatinine), MiBP (23.3 μg/g of creatinine), and MnBP (58.2 μg/g of creatinine) detected in the cases were significantly higher than those (15.7 μg/g of creatinine for MEP, 19.4 μg/g of creatinine for MiBP, and 43.9 μg/g of creatinine for MnBP) in the controls (p \< 0.05). Increasing risks of clinical pregnancy loss were observed from the first to fourth quartiles of the MEP, MiBP, and MnBP concentrations (p \< 0.05 for trend). We concluded that exposure to MEP, MiBP, and MnBP was associated with an increased risk of clinical pregnancy loss.

}, keywords = {Adult, Beijing, Case-Control Studies, Embryo Loss, Environmental Monitoring, Esters, Female, Humans, Metabolome, Middle Aged, Odds Ratio, Phthalic Acids, Pregnancy, Risk Factors, Young Adult}, issn = {1520-5851}, doi = {10.1021/acs.est.5b02617}, author = {Mu, Di and Gao, Fumei and Fan, Zhanlan and Shen, Huan and Peng, Hui and Hu, Jianying} } @article {109, title = {Temporal trends of polychlorinated biphenyls, polybrominated diphenyl ethers, and perfluorinated compounds in Chinese sturgeon (Acipenser sinensis) eggs (1984-2008).}, journal = {Environ Sci Technol}, volume = {49}, year = {2015}, month = {2015 Feb 03}, pages = {1621-30}, abstract = {

Because investigation on the temporal trends of persistent halogenated compounds (PHCs) is necessary to predict their future impacts on the environment and human health and evaluate the effectiveness of regulations on their production and usage, it is of concern to investigate annual temporal trends of PHCs in biota samples. This study examined the temporal trends of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorinated compounds (PFCs) in Chinese sturgeon (Acipenser sinensis) eggs over a period of 25 years (1984-2008), and 62 PCBs (19.2-1030 ng/g dw for total PCBs), 16 PBDEs (4.7-572 ng/g dw for total PBDEs), and 14 PFCs (26-46 ng/g dw for total PFCs) were detected. Although a decreasing temporal trend was observed for total PCBs with annual reduction rate of 3.4\% (ρ = 0.005), a clear break point was observed around 1991, indicating their continuing emission in the 1980s in China. All major PBDEs showed increasing temporal trends, with annual change rates at 3.5-10.2\% over the 25 years, but a sharp decreasing trend was observed after 2006, indicating a rapid response to the banning of PBDE usage in China in 2004. The greatest annual rate of increase was observed for BDE-28 (10.2\%) followed by BDE-100 (7.7\%), which would be due to metabolism input from higher brominated PBDEs. Significantly increasing temporal trends were observed for all PFCs, and the annual rates of increase were 7.9\% and 5.9\% for total perfluorinated carboxylic acids and perfluorooctanesulfonate (PFOS), respectively. A peak concentration for PFOS was observed in 1989, which may be related to the import history of PFCs in China. The present study is the first report of systematic temporal trends of PHCs in biota samples from China and shows that regulatory policy is needed to reduce their potential health and ecological risk in China considering the increasing temporal trends of PBDEs and PFCs.

}, keywords = {Animals, China, Environmental Monitoring, Fishes, Fluorocarbons, Halogenated Diphenyl Ethers, Humans, Longitudinal Studies, Ovum, Polybrominated Biphenyls, Polychlorinated Biphenyls}, issn = {1520-5851}, doi = {10.1021/es505378b}, author = {Jianxian, Sun and Hui, Peng and Jianying, Hu} } @article {105, title = {Untargeted Identification of Organo-Bromine Compounds in Lake Sediments by Ultrahigh-Resolution Mass Spectrometry with the Data-Independent Precursor Isolation and Characteristic Fragment Method.}, journal = {Anal Chem}, volume = {87}, year = {2015}, month = {2015 Oct 20}, pages = {10237-46}, abstract = {

While previous studies have found that unknown natural and synthetic organo-bromine compounds (NSOBCs) contributed more than 99\% of the total organic bromine (Br) in the environment, there was no efficient method for untargeted screening to identify NSOBCs in environmental matrixes. A novel untargeted method for identifying NSOBCs, based on ultrahigh-resolution mass spectrometry (UHRMS) with the Q Exactive instrument was developed. This method included a data-independent precursor isolation and characteristic fragment (DIPIC-Frag) procedure to identify NSOBCs. A total of 180 successive 5-m/z-wide windows were used to isolate precursor ions. This resulted in a sufficient dynamic range and specificity to identify peaks of Br fragment ions for analysis. A total of 2520 peaks of NSOBC compounds containing Br were observed in sediments from Lake Michigan, United States. A new chemometric strategy which combined chromatographic profiles, isotopic peaks, precursor isolation window information, and intensities was used to identify precursor ions and chemical formulas for detecting NSOBCs. Precursor ions for 2163 of the 2520 NSOBCs peaks (86\%) were identified, and chemical formulas for 2071 NSOBCs peaks (82\%) were determined. After exclusion of isotopic peaks, 1593 unique NSOBCs were identified and chemical formulas derived for each. Most of the compounds identified had not been reported previously and had intensities which were 100- to 1000-fold greater than the congeners of polybrominated diphenyl ethers (PBDEs). In extracts of sediments, these compounds exhibited variations in intensities (\<10(3) to \~{}10(8)), m/z values (170.9438-997.5217), retention times on a C18 column (1.0-29.3 min), and the number of Br atoms (1-8). Generally, compounds with greater m/z values had longer retention times and greater numbers of Br atoms. Three compounds were used in a proof-of-concept experiment to demonstrate that structures of some of the screened NSOBCs could be further predicted by combining searching of database libraries and high-resolution MS(2) spectra.

}, keywords = {Databases, Chemical, Geologic Sediments, Hydrocarbons, Brominated, Lakes, Mass Spectrometry}, issn = {1520-6882}, doi = {10.1021/acs.analchem.5b01435}, author = {Peng, Hui and Chen, Chunli and Saunders, David M V and Sun, Jianxian and Tang, Song and Codling, Garry and Hecker, Markus and Wiseman, Steve and Jones, Paul D and Li, An and Rockne, Karl J and Giesy, John P} } @article {112, title = {Isomer-specific accumulation of perfluorooctanesulfonate from (N-ethyl perfluorooctanesulfonamido)ethanol-based phosphate diester in Japanese Medaka (Oryzias latipes).}, journal = {Environ Sci Technol}, volume = {48}, year = {2014}, month = {2014 Jan 21}, pages = {1058-66}, abstract = {

While (N-ethyl perfluorooctanesulfonamido)ethanol (FOSE) -based phosphate diester (diSPAP) has been proposed as a candidate precursor of perfluorooctanesulfonate (PFOS), its potential biotransformation to PFOS has not been verified. Metabolism of diSPAP was investigated in Japanese medaka ( Oryzias latipes ) after exposure in water for 10 days, followed by 10 days of depuration. Branched isomers of diSPAP (B-diSPAP) were preferentially enriched in medaka exposed to diSPAP, with the proportion of branched isomers (BF) ranging from 0.56 to 0.80, which was significantly greater than that in the water to which the medaka were exposed (0.36) (p \< 0.001). This enrichment was due primarily to preferential uptake of B-diSPAP. PFOS together with perfluorooctanesulfonamide (PFOSA), N-ethyl perfluorooctanesulfonamide (NEtFOSA), 2-(perfluorooctanesulfonamido)acetic acid (FOSAA), NEtFOSAA, FOSE, and NEtFOSE were detected in medaka exposed to diSPAP, which indicated the potential for biotransformation of diSPAP to PFOS via multiple intermediates. Due to preferential metabolism of branched isomers, FOSAA and PFOSA exhibited greater BF values (\>0.5) than those of NEtFOSA, NEtFOSAA, and NEtFOSE (\<0.2). Such preferential metabolism of branched isomers along the primary pathway of metabolism and preferential accumulation of B-diSPAP led to enrichment of branched PFOS (B-PFOS) in medaka. Enrichment of B-PFOS was greater for 3-, 4-, and 5-perfluoromethyl PFOS (P3MPFOS, P4MPFOS, and P5MPFOS), for which values of BF were 0.58 {\textpm} 0.07, 0.62 {\textpm} 0.06, and 0.61 {\textpm} 0.05 (day 6), respectively; these values are 5.8-, 7.8-, and 6.4-fold greater than those of technical PFOS. This work provides evidence on the isomer-specific accumulation of PFOS from diSPAP and will be helpful to track indirect sources of PFOS in the future.

}, keywords = {Alkanesulfonic Acids, Animals, Biotransformation, Chromatography, High Pressure Liquid, Environmental Monitoring, Esters, Fluorocarbons, Gas Chromatography-Mass Spectrometry, Half-Life, Hydrocarbons, Fluorinated, Isomerism, Kinetics, Metabolic Networks and Pathways, Organophosphorus Compounds, Oryzias, Phosphates, Reference Standards, Sulfonamides}, issn = {1520-5851}, doi = {10.1021/es404867w}, author = {Peng, Hui and Zhang, Shiyi and Sun, Jianxian and Zhang, Zhong and Giesy, John P and Hu, Jianying} } @article {110, title = {Occurrences of three classes of antibiotics in a natural river basin: association with antibiotic-resistant Escherichia coli.}, journal = {Environ Sci Technol}, volume = {48}, year = {2014}, month = {2014 Dec 16}, pages = {14317-25}, abstract = {

To investigate the occurrence of antibiotics in urban rivers and their association with antibiotic-resistant Escherichia coli, 20 (fluoro)quinolone antibiotics (FQs), 16 tetracycline antibiotics (TCs) and their degradation products, and 25 sulfonamides (SAs) and some degradation products were determined in 45 river samples and 13 discharged wastewater samples collected from Wenyu River and its tributaries and 4 composite effluent samples from sewage treatment plants in Beijing, China. Fifteen FQs, eight TCs, including four degradation chemicals, and sixteen SAs, including four acetylated products, were detected in the river water. The SAs were the dominant antibiotic (total concentrations up to 3164.0 ng/L) in river water, followed by FQs (1430.3 ng/L) and TCs (296.6 ng/L). The sum concentrations for each class of detected antibiotic in the 13 discharge site samples were higher than those in river samples, up to 12326.7 ng/L for SAs, 6589.2 ng/L for FQs, and 730.1 ng/L for TCs, largely contributing to the high concentrations in the river basin. Log-linear regression analysis confirmed that the concentrations of FQs, TCs, and SAs in the Wenyu River basin were strongly correlated with the number of E. coli resistant to FQs (p \< 0.05), TCs (p \< 0.05), and SAs (p \< 0.05), providing evidence for the environmental impacts of antibiotic usage.

}, keywords = {Anti-Bacterial Agents, China, Drug Resistance, Bacterial, Environmental Monitoring, Escherichia coli, Fluoroquinolones, Rivers, Sulfonamides, Tetracyclines, Waste Water, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/es503700j}, author = {Zhang, Qinqin and Jia, Ai and Wan, Yi and Liu, Hong and Wang, Kunping and Peng, Hui and Dong, Zhaomin and Hu, Jianying} } @article {111, title = {Trophic transfer of dechloranes in the marine food web of Liaodong Bay, north China.}, journal = {Environ Sci Technol}, volume = {48}, year = {2014}, month = {2014 May 20}, pages = {5458-66}, abstract = {

Dechloranes are of particular concern because of their ubiquity in environmental matrices, but little is known about their trophic transfer in aquatic food web. This study investigated the trophic transfer of seven dechloranes in a marine food web from Liaodong Bay, China. Dechloranes were determined in sediments and 15 marine species including benthic invertebrates, fish and gulls collected from Liaodong Bay. Biomagnification factors (BMFTL) of dechloranes in black-headed gulls were calculated to be 6.4, 1.7, 0.45, 0.36, 0.14, and 0.11 for mirex, Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), antiundecachloropentacyclooctadecadiene (anti-Cl11DP), syn-dechlorane plus (syn-DP), and anti-DP. Significantly positive relationships were found between lipid equivalent concentrations of mirex, Dec 602, and anti-Cl11DP and trophic levels, and the trophic magnification factors (TMFs) were 13, 3.7, and 5.6, respectively, indicating that these compounds undergo trophic magnification in the aquatic food web. Lipid equivalent concentrations of Dec 603 and DP isomers did not exhibit a statistically significant correlation with trophic levels. The relatively low trophic magnification potentials of Dec 603 and DP isomers were possibly due to their extreme hydrophobicity (logKOW: 11.2-11.3) and subsequent low bioavailabilities compared with mirex (7.0), Dec 602 (8.1) and anti-Cl11DP. The results provided important information for understanding the ecological risk of dechloranes.

}, keywords = {Animals, Aquatic Organisms, Bays, Charadriiformes, China, Environmental Monitoring, Fishes, Food Chain, Geologic Sediments, Hydrocarbons, Chlorinated, Invertebrates, Ontario, Regression Analysis, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/es500229y}, author = {Peng, Hui and Wan, Yi and Zhang, Kun and Sun, Jianxian and Hu, Jianying} } @article {114, title = {Derivatization method for sensitive determination of fluorotelomer alcohols in sediment by liquid chromatography-electrospray tandem mass spectrometry.}, journal = {J Chromatogr A}, volume = {1288}, year = {2013}, month = {2013 May 03}, pages = {48-53}, abstract = {

Fluorotelomer alcohols (FTOHs) are the main precursors of environmentally ubiquitous perfluorinated acids, and determination of FTOHs at low concentrations presents significant challenges. In this study, a new liquid chromatography-electrospray mass spectrometry (LC-ESI-MS) method in conjunction with low-energy collision dissociation tandem mass spectrometry (CID-MS/MS) was developed by employing an optimized derivatization reaction with dansyl chloride (DNS) in acetonitrile under catalysis of 4-(dimethylamino)-pyridine (DMAP). The instrument detection limits (IDLs) of the newly developed method were 0.014, 0.015, 0.014, 0.0075 and 0.0093μg/L for 4:2 FTOH, 6:2 FTOH, 8:2 FTOH, 10:1 FTOH and 10:2 FTOH respectively, which were 7.5-241 times lower than those without derivatizaiton and 57-357 times lower than previous GC/MS method. The method was successfully applied to analyze FTOHs in sediments combined with WAX and silica cartridges cleanup. The overall method recoveries were from 67{\textpm}6.0\% to 83{\textpm}9.4\% with matrix effects of \<15\%. The limits of quantification for all FTOHs were 0.017-0.060ng/gdry weight (dw). The method was applied to analyze six marine sediment samples from Liaodong Bay, China. All FTOHs except for 10:1 FTOH were detected, and the total concentrations of FTOHs were 0.19-0.52ng/gdw. The developed method provides a new method to sensitively determine FTOHs in environmental matrices.

}, keywords = {Alcohols, China, Chromatography, High Pressure Liquid, Environmental Pollutants, Fluorocarbons, Geologic Sediments, Reproducibility of Results, Sensitivity and Specificity, Spectrometry, Mass, Electrospray Ionization, Tandem Mass Spectrometry}, issn = {1873-3778}, doi = {10.1016/j.chroma.2013.02.085}, author = {Peng, Hui and Hu, Kejun and Zhao, Fanrong and Hu, Jianying} } @article {113, title = {High-density lipoprotein of patients with type 2 diabetes mellitus upregulates cyclooxgenase-2 expression and prostacyclin I-2 release in endothelial cells: relationship with HDL-associated sphingosine-1-phosphate.}, journal = {Cardiovasc Diabetol}, volume = {12}, year = {2013}, month = {2013 Jan 30}, pages = {27}, abstract = {

BACKGROUND: Dysfunctional high-density lipoprotein (HDL) may have pro-inflammatory effects on the endothelial cells,which causes atherosclerosis in type 2 diabetes mellitus (T2DM). HDL is a major carrier of sphingosine-1-phosphate (S1P) in plasma while S1P exhibits multiple biological activities. However, potential role of HDL and S1P in T2DM remains unexplored. We hypothesized that diabetic HDL with higher contents of S1P exerts beneficial effects on the vascular system.

METHODS: Subjects with T2DM with or without proved large arteries atherosclerosis and normal controls (n=15 for each group) were recruited in the present study. HDL was isolated from the subjects by ultracentrifugation. The levels of HDL-associated S1P were determined by UPLC-MS/MS. The protective function of diabetic HDL and S1P was evaluated by measuring cyclooxygenase-2 (COX-2) expression and prostacyclin I-2 (PGI-2) release by human umbilical vein endothelial cells (HUVECs) using western blot and enzyme-linked immunosorbent assay (ELISA), respectively.

RESULTS: The S1P levels in isolated HDL were significantly increased in T2DM subjects compared with controls (235.6 {\textpm} 13.4 vs 195.0 {\textpm} 6.4 ng/mg, P\< 0.05). The diabetic HDL exerted greater protective effects on inducing COX-2 expression and PGI-2 release by HUVECs than those of control HDL (p \< 0.05, p \< 0.01, respectively). Pertussis toxin, a common inhibitor of G-couple protein receptors, and VPC 23019, an antagonist of S1P receptor 1 and 3 significantly attenuated HDL-induced COX-2 expression and PGI-2 release.

CONCLUSIONS: Diabetic HDL carries higher level of S1P compared with normal HDL, which has the potential to contribute to protective effects on endothelial cells by inducing COX-2 expression and PGI-2 release. These findings provide a new insight of S1P function in T2DM patients, possibly leading to a new therapeutic target.

}, keywords = {Adult, Aged, Cells, Cultured, Cyclooxygenase 2, Diabetes Mellitus, Type 2, Endothelial Cells, Epoprostenol, Female, Gene Expression Regulation, Enzymologic, Human Umbilical Vein Endothelial Cells, Humans, Lipoproteins, HDL, Lysophospholipids, Male, Middle Aged, Sphingosine, Up-Regulation}, issn = {1475-2840}, doi = {10.1186/1475-2840-12-27}, author = {Tong, Xunliang and Peng, Hui and Liu, Donghui and Ji, Liang and Niu, Chenguang and Ren, Jun and Pan, Bing and Hu, Jianying and Zheng, Lemin and Huang, Yining} } @article {121, title = {Molecular and physiological characterization of fluoroquinolone resistance in relation to uropathogenicity among Escherichia coli isolates isolated from Wenyu River, China.}, journal = {Chemosphere}, volume = {87}, year = {2012}, month = {2012 Mar}, pages = {37-42}, abstract = {

Increasing antibacterial resistance and pathogenicity in the environment is of growing concern due to its potential human risk. In the present study, 236 Escherichia coli isolates were collected from Wenyu River in China on drugless (48 isolates) and quinolone-containing plates (189 isolates). Their minimum inhibitory concentrations (MICs) were determined ranging from 0.125 μg mL(-1) to 128 μg mL(-1). Mutation points related to fluoroquinolone resistance were observed at S83 to L and D87 to N or Y in the GyrA subunit and S80 to R or I and E84 to G in the ParC subunit. Generally, MICs of LEV and GAT are dependent on the patterns of these mutation points. The profile with three mutation points was related to LEV-resistant E. coli isolates, and the (S83L, D87N+S80I) mutation profile was most prevalent (65.7\%) in LEV-resistant isolates, while a large proportion of isolates, even those with three mutation points, were susceptive to GAT. The incidence of virulence factors in LEV-resistant isolates (44.7\%, 59/132) was much higher than in nonresistant isolates (23.1\%, 24/104) (χ(2)=11.925, 1{\textdegree} of freedom, p\<0.001) indicating that fluoroquinolone-resistant E. coli would pose a potential risk. A similar distribution was also found in isolates resistant to GAT (χ(2)=7.843, 1{\textdegree} of freedom, p=0.0079).

}, keywords = {Anti-Bacterial Agents, China, Drug Resistance, Bacterial, Escherichia coli, Fluoroquinolones, Rivers, Water Pollutants, Chemical}, issn = {1879-1298}, doi = {10.1016/j.chemosphere.2011.11.050}, author = {Sun, Jianxian and Hu, Jianying and Peng, Hui and Shi, Jiachen and Dong, Zhaomin} } @article {116, title = {Simultaneous determination of mono- and disubstituted polyfluoroalkyl phosphates in drinking water by liquid chromatography-electrospray tandem mass spectrometry.}, journal = {J Chromatogr A}, volume = {1227}, year = {2012}, month = {2012 Mar 02}, pages = {245-52}, abstract = {

A sensitive liquid chromatography-electrospray tandem mass spectrometry method was established for the simultaneous determination of five monosubstituted polyfluoroalkyl phosphates (monoPAPs) and eight disubstituted polyfluoroalkyl phosphates (diPAPs) in drinking water. Complete separation and good retention for 13 polyfluoroalkyls phosphates (PAPs) were achieved with a Waters ACUITY UPLC BEH C8 column using a mixture of methanol/water containing 0.1\% NH$_{4}$OH as the mobile phases. Extraction of drinking water samples was performed on weak anion exchange (WAX) cartridges, and the recoveries of target compounds were from 65 to 110\%. The limits of quantization (LOQs) for 13 analytes were in the range of 0.4-40 ng/L. This method was applied to analyze the PAPs in drinking water samples from three cities in China. Of the 13 PAPs, six PAPs including 6:2 monoPAP (13.0 ng/L), 8:2 monoPAP (3.6 ng/L), 10:1 monoPAP (4.3-70.3 ng/L), 10:2 monoPAP (1.4-5.6 ng/L), 8:2 diPAP (0.10 ng/L), and 10:1 diPAP (0.8-3.8 ng/L) were detected.

}, keywords = {China, Chromatography, Ion Exchange, Drinking Water, Fluorocarbons, Phosphates, Reproducibility of Results, Sensitivity and Specificity, Solid Phase Extraction, Tandem Mass Spectrometry, Water Pollutants, Chemical}, issn = {1873-3778}, doi = {10.1016/j.chroma.2012.01.004}, author = {Ding, Huanhuan and Peng, Hui and Yang, Min and Hu, Jianying} } @article {115, title = {Tissue distribution, maternal transfer, and age-related accumulation of dechloranes in Chinese sturgeon.}, journal = {Environ Sci Technol}, volume = {46}, year = {2012}, month = {2012 Sep 18}, pages = {9907-13}, abstract = {

While dechloranes have been detected in environmental media and wildlife, limited information was available on their tissue distribution in wildlife. Syn-dechlorane plus (syn-DP), anti-DP, syn-undecachloropentacyclooctadecadiene (syn-Cl(11)DP), anti-Cl(11)DP, dechlorane 602, dechlorane 603 and mirex were measured in 13 organs of 17 female Chinese sturgeon (Acipenser sinensis). Dechloranes were detected in all tissues and the highest concentrations of total dechloranes were detected in heart (87 pg/g ww, 4.5-645 pg/g ww), followed by adipose (61 pg/g ww, 14-531 pg/g ww) and eggs (57 pg/g ww, 13-261 pg/g ww). The tissue distribution of DP was mainly determined by lipid partition, while Dec 602 and Dec 603 preferred to accumulate in the intestine and stomach. The values of f(anti) (the concentration of anti-DP relative to the sum concentration of DP) in maternal tissues (0.72 {\textpm} 0.03 in muscle) were significantly higher than those found in eggs (0.65 {\textpm} 0.04) (p \< 0.001), while f(anti-Cl11DP) (the concentration of anti-Cl(11)DP relative to the sum concentration of Cl(11)DP) in maternal tissues (0.59 {\textpm} 0.10 in muscle) was significantly lower than that in eggs (0.75 {\textpm} 0.13) (p \< 0.05). High maternal transfer efficiencies of dechloranes were observed in eggs, which accounted for 49\% of the total body burden, and the ratios of concentrations in eggs to maternal tissues (EMR) for mirex, Dec 602, Dec 603, syn-Cl(11)DP, anti-Cl(11)DP, syn-DP, and anti-DP were 18, 8.8, 5.2, 2.6, 5.2, 5.5 and 3.7, respectively, which are dependent on their K(OW) values (r = -0.66, p \< 0.01). Negative age-related trends were observed for mirex, Dec 603, syn-Cl(11)DP and anti-Cl(11)DP in eggs (R(2) = 0.28-0.38, p = 0.02-0.05), which were possibly due to their high transfer efficiencies to eggs from maternal body (49\%).

}, keywords = {Animals, China, Eggs, Environmental Monitoring, Female, Fishes, Flame Retardants, Hydrocarbons, Chlorinated, Polycyclic Compounds, Tissue Distribution, Water Pollutants, Chemical}, issn = {1520-5851}, doi = {10.1021/es3025879}, author = {Peng, Hui and Zhang, Kun and Wan, Yi and Hu, Jianying} } @article {117, title = {Occurrence and source apportionment of sulfonamides and their metabolites in Liaodong Bay and the adjacent Liao River basin, North China.}, journal = {Environ Toxicol Chem}, volume = {30}, year = {2011}, month = {2011 Jun}, pages = {1252-60}, abstract = {

The presence of antibiotics in the environment is of great concern because of their potential for resistance selection among pathogens. In the present study we investigated the occurrence of 19 sulfonamides, five N-acetylated sulfonamide metabolites, and trimethoprim in the Liao River basin and adjacent Liaodong Bay, China, as well as 10 human/agricultural source samples. Within the 35 river samples, 12 sulfonamides, four acetylated sulfonamides, and trimethoprim were detected, with the dominant being sulfamethoxazole (66.6 ng/L), N-acetylsulfamethoxazole (63.1 ng/L), trimethoprim (29.0 ng/L), sulfadiazine (14.0 ng/L), and sulfamonomethoxine (8.4 ng/L); within the 36 marine samples, 10 chemicals were detected, with the main contributions from sulfamethoxazole (25.2 ng/L) and N-acetylsulfamethoxazole (28.6 ng/L). Sulfamethoxazole (25.9\%), N-acetylsulfamethoxazole (46.6\%), trimethoprim (22.9\%), and sulfapyridine (1.4\%) were the main chemicals from human sources, while sulfamonomethoxine, sulfamethazine, sulfaquinoxaline, sulfaguanidine, sulfadiazine, sulfanilamide, and sulfamethoxypyridazine were dominant in the animal husbandry sources, specifically, swine and poultry farms, and sulfamethoxazole (91\%) was dominant in the mariculture source. A principal component analysis with multiple linear regression was performed to evaluate the source apportionment of total sulfonamides in Liaodong Bay. It was found that animal husbandry contributed 15.2\% of total sulfonamides, while human sources contributed 28.5\%, and combined human and mariculture sources contributed 56.3\%. In addition, the mariculture contribution was 24.1\% of total sulfonamides into the sea based on mass flux estimation. The present study is the first report that the environmental levels of sulfonamide metabolites were comparable to the corresponding parents; therefore, we should pay attention to their environmental occurrence. Source apportionment showed human discharge (60.7\%) significantly contributed to these antibiotics in Liaodong Bay, which provides important information for environmental management.

}, keywords = {Agriculture, Anti-Bacterial Agents, Aquaculture, China, Environmental Monitoring, Humans, Linear Models, Principal Component Analysis, Rivers, Seawater, Spectrometry, Mass, Electrospray Ionization, Sulfamethazine, Sulfamethoxazole, Sulfamethoxypyridazine, Sulfamonomethoxine, Sulfapyridine, Sulfaquinoxaline, Sulfonamides, Tandem Mass Spectrometry, Trimethoprim, Water Pollutants, Chemical, Water Pollution, Chemical}, issn = {1552-8618}, doi = {10.1002/etc.508}, author = {Jia, Ai and Hu, Jianying and Wu, Xiaoqin and Peng, Hui and Wu, Shimin and Dong, Zhaomin} } @article {118, title = {Determination and occurrence of retinoic acids and their 4-oxo metabolites in Liaodong Bay, China, and its adjacent rivers.}, journal = {Environ Toxicol Chem}, volume = {29}, year = {2010}, month = {2010 Nov}, pages = {2491-7}, abstract = {

Retinoic acids (RAs) and their metabolites play an important role in abnormal morphological development and are speculated to be a possible cause for the increased rates of deformities in wild frog populations. In the current study, a method using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry was developed for simultaneously analyzing all-trans-RA (at-RA), 13-cis-RA (13c-RA), 9-cis-RA (9c-RA), and their 4-oxo metabolites, all-trans-4-oxo-RA (at-4-oxo-RA), 13-cis-4-oxo-RA (13c-4-oxo-RA), and 9-cis-4-oxo-RA (9c-4-oxo-RA) in wastewaters and surface waters. Method detection limits were matrix dependent, ranging from 0.02 to 0.37 ng/L. The method was used to investigate the occurrence of RAs and 4-oxo-RAs in Liaodong Bay and its adjacent rivers. Of these six retinoids, at-RA, 13c-RA, at-4-oxo-RA, and 13c-4-oxo-RA were detected in river waters at detection frequencies of 100\%, 92\%, 48.6\%, and 21.6\%, and concentrations of 0.05 to 1.23 ng/L, less than 0.03 to 0.41 ng/L, less than 0.02 to 1.00 ng/L, and less than 0.06 to 0.81 ng/L, respectively. Retinoic acids were detected for the first time in the aquatic environment and were found to be more persistent than 4-oxo-RAs. The hazard quotient for mortality of frog embryos caused by induction by retinoids detected in the current study was then estimated, and the value was calculated to be 0.09. No retinoid was detected in seawaters.

}, keywords = {China, Chromatography, High Pressure Liquid, Rivers, Spectrometry, Mass, Electrospray Ionization, Stereoisomerism, Tretinoin, Water Pollutants, Chemical}, issn = {1552-8618}, doi = {10.1002/etc.322}, author = {Wu, Xiaoqin and Hu, Jianying and Jia, Ai and Peng, Hui and Wu, Shimin and Dong, Zhaomin} } @article {119, title = {Tissue distribution and maternal transfer of poly- and perfluorinated compounds in Chinese sturgeon (Acipenser sinensis): implications for reproductive risk.}, journal = {Environ Sci Technol}, volume = {44}, year = {2010}, month = {2010 Mar 01}, pages = {1868-74}, abstract = {

It is critical to investigate the tissue distribution and maternal transfer of poly- and perfluorinated compounds (PFCs) in wild fish for assessing potential effects on ecosystems. Concentrations of 23 PFCs in nine organs and egg were measured in 16 17- to 25-year-old female Chinese sturgeon (Acipenser sinensis, an anadromous fish), that died during propagation. Three polyfluorinated amides were detected in stomach, intestine, and gills and 7:3 FTCA was specifically accumulated in liver. The greatest total concentration of PFCs in egg was 35.1 +/- 10.4 ng/g ww and was predominated by perfluorooctane sulfonate (PFOS) and perfluorotridecanoate acid (PFTriDA). The longer-chain C(11)-C(14) and C(16) perfluorinated carboxylates were more accumulated in Chinese sturgeon than PFOS, partly due to the increasing trends of PFCAs with fish age. Maternal transfer ratios of PFCs expressed as ratios of concentrations in the egg to those in the liver ranged from 0.79 (perfluorooctanoate) to 5.5 (PFTriDA), depending on their carbon chain lengths or protein-water coefficients. The PFOS equivalent of PFC mixtures, calculated by multiplying the relative potency factor of each PFC to PFOS by the corresponding concentration, ranged from 90.6 to 262 ng/g. The hazard quotient was 0.20, implying potential reproductive effects of PFCs on Chinese sturgeon.

}, keywords = {Alkanesulfonic Acids, Animals, Female, Fertility, Fertilization in Vitro, Fishes, Fluorocarbons, Organ Specificity, Reproduction, Risk Factors, Tissue Distribution}, issn = {0013-936X}, doi = {10.1021/es903248d}, author = {Peng, Hui and Wei, Qiwei and Wan, Yi and Giesy, John P and Li, Luoxin and Hu, Jianying} } @article {120, title = {Malformations of the endangered Chinese sturgeon, Acipenser sinensis, and its causal agent.}, journal = {Proc Natl Acad Sci U S A}, volume = {106}, year = {2009}, month = {2009 Jun 09}, pages = {9339-44}, abstract = {

The anadromous Chinese sturgeon (Acipenser sinensis) is endangered and listed among the first class of protected animals in China. The possible causes for the decline of this species are the effects of synthetic chemicals, and loss of critical habitat. Chinese sturgeon in the Yangtze River have accumulated triphenyltin (TPT) to 31-128 ng/g wet weigh (ww) in liver, which is greater than the concentrations of tributyltin (\<1.0 ng/g ww). Maternal transfer of TPT has resulted in concentrations of 25.5 +/- 13.0 ng/g ww in eggs of wild Chinese sturgeon, which poses a significant risk to the larvae naturally fertilized or hatched in the Yangtze River. The incidence of deformities in fry was 7.5\%, with 1.2\% of individuals exhibiting ocular abnormal development, and 6.3\% exhibited skeletal/morphological deformations. The incidences of both ocular and skeletal/morphological deformations were directly proportional to the TPT concentration in the eggs of both the Chinese sturgeon and the Siberian sturgeon (Acipenser baerii) in controlled laboratory studies. The rates of deformities in the controlled studies were consistent with the rates caused at the similar concentrations in eggs collected from the field. Thus, TPT is the causal agent to induce the malformation of larvae of Chinese sturgeon. The incidence of deformed larvae of Chinese sturgeon is an indicator of overall population-level effects of TPT on Chinese sturgeon, because TPT at environmentally relevant concentrations can result in significantly decrease both quality and quantity of eggs and spawning frequency of fish.

}, keywords = {Animals, China, Fishes, Organotin Compounds, Trialkyltin Compounds, Water Pollutants, Chemical}, issn = {1091-6490}, doi = {10.1073/pnas.0809434106}, author = {Hu, Jianying and Zhang, Zhaobin and Wei, Qiwei and Zhen, Huajun and Zhao, Yanbin and Peng, Hui and Wan, Yi and Giesy, John P and Li, Luoxin and Zhang, Bo} }