Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.scitotenv.2017.09.233
Document author version
Title (Primary) Characterizing chemical transformation of organophosphorus compounds by 13C and 2H stable isotope analysis
Author Wu, L.; Chládková, B.; Lechtenfeld, O.J. ORCID logo ; Lian, S.; Schindelka, J.; Herrmann, H.; Richnow, H.H.
Source Titel Science of the Total Environment
Year 2018
Department ISOBIO; ANA
Volume 615
Page From 20
Page To 28
Language englisch
Keywords Compound specific isotope analysis; Parathion; TCEP; Hydrolysis; Photolysis; Transformation products
UFZ wide themes RU3; ProVIS;

Continuous and excessive use of organophosphorus compounds (OPs) has led to environmental contaminations which raise public concerns. This study investigates the isotope fractionation patterns of OPs in the aquatic environment dependence upon hydrolysis, photolysis and radical oxidation processes. The hydrolysis of parathion (EP) and methyl parathion (MP) resulted in significant carbon fractionation at lower pH (pH 2–7, εC = − 6.9 ~ − 6.0‰ for EP, − 10.5 ~ − 9.9‰ for MP) but no detectable carbon fractionation at higher pH (pH 12). Hydrogen fractionation was not observed during any of the hydrolysis experiments. These results indicate that compound specific isotope analysis (CSIA) allows distinction of two different pH-dependent pathways of hydrolysis. Carbon and hydrogen isotope fractionation were determined during UV/H2O2 photolysis of EP and tris(2-chloroethyl) phosphate (TCEP). The constant δ2H values determined during the OH radical reaction of EP suggested that the rate-limiting step proceeded through oxidative attack by OH radical on the Pdouble bond; length as m-dash<img border="0" alt="double bond; length as m-dash" src="" class="glyphImg">S bond. The significant H isotope enrichment suggested that OH radical oxidation of TCEP was caused by an H-abstraction during the UV/H2O2 processes (εH = − 56 ± 3‰). Fenton reaction was conducted to validate the H isotope enrichment of TCEP associated with radical oxidation, which yielded εH of − 34 ± 5‰. Transformation products of OPs during photodegradation were identified using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS). This study highlights that the carbon and hydrogen fractionation patterns have the potential to elucidate the transformation of OPs in the environment.

Persistent UFZ Identifier
Wu, L., Chládková, B., Lechtenfeld, O.J., Lian, S., Schindelka, J., Herrmann, H., Richnow, H.H. (2018):
Characterizing chemical transformation of organophosphorus compounds by 13C and 2H stable isotope analysis
Sci. Total Environ. 615 , 20 - 28 10.1016/j.scitotenv.2017.09.233