@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 = {<p>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 \&lt; 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 (\&gt;0.5) than those of NEtFOSA, NEtFOSAA, and NEtFOSE (\&lt;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.</p>},
	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 {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 = {<p>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.</p>},
	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}
}
