title: Stereoisomeric isolation and stereoselective fate of insecticide paichongding in flooded paddy soils.
abstract: Chiral insecticide paichongding (IPP) is one of the prospective substitutes for imidacloprid used in China due to its higher activity against imidacloprid-resistant insects. However, little is known about the fate of IPP in soils, including especially the different behaviors among its stereoisomers. In this study, four stereoisomers of IPP were separated and applied in flooded soils. Kinetics of mineralization, extractable residues, and bound residues showed diastereoselectivity in IPP degradation, with enantiomers (5S,7R)-IPP (IPP-SR) and (5R,7S)-IPP (IPP-RS) being more readily mineralized and preferentially bound to soils than enantiomers (5R,7R)-IPP (IPP-RR) and (5S,7S)-IPP (IPP-SS). The overall mineralization was rather limited and did not exceed 4% of the spiked rate. Concurrent to the decreases of extractable residues, the fraction of bound residues increased with time and reached about 34% of the applied radioactivity for (14)C-IPP-SR and (14)C-IPP-RS as compared to about 23% for (14)C-IPP-RR or (14)C-IPP-SS. Soil properties such as organic matter content and pH likely contributed to the variability. Relatively rapid formation of bound residue suggests that IPP may be quickly detoxified in flooded paddy soil, decreasing the potential for off-site transport such as leaching or runoff, especially for enantiomers IPP-SR and IPP-RS.
authors.affiliation: Institute of Nuclear Agricultural Sciences, Zhejiang University , Hangzhou 310029, China.
authors.forename: Juying
authors.initials: J
authors.lastname: Li
authors.forename: Jianbo
authors.initials: J
authors.lastname: Zhang
authors.forename: Chao
authors.initials: C
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.forename: Haiyan
authors.initials: H
authors.lastname: Wang
authors.forename: Jay
authors.initials: J
authors.lastname: Gan
authors.forename: Qingfu
authors.initials: Q
authors.lastname: Ye
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Xu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Li
mesh_terms: D053961:Azabicyclo Compounds / Q000737:chemistry* / Q000302:isolation & purification*; D002245:Carbon Dioxide / Q000737:chemistry; D002250:Carbon Radioisotopes / Q000032:analysis; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D055868:Floods; D007306:Insecticides / Q000737:chemistry / Q000302:isolation & purification*; D008903:Minerals / Q000737:chemistry; D012275:Oryza / Q000254:growth & development*; D011725:Pyridines / Q000737:chemistry* / Q000302:isolation & purification*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D013237:Stereoisomerism
chemical_list: D053961:Azabicyclo Compounds; D002250:Carbon Radioisotopes; D007306:Insecticides; D008903:Minerals; D011725:Pyridines; D012987:Soil; D012989:Soil Pollutants; C588015:paichongding; D002245:Carbon Dioxide