@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 {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 {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} }