摘要
烟碱类杀虫剂吡虫啉(imidacloprid,IMI)在环境中可代谢为生物活性提高10倍的烯式吡虫啉(olefin IMI)。研究了olefin IMI的光稳定性、光解动力学和光解代谢途径。结果表明:olefin IMI在避光条件下较为稳定,室温下放置400d后,olefin IMI含量仅减少3%;而在室内模拟日光条件下,olefin IMI易于分解,光解反应符合一级动力学方程(r>0.99),半衰期为4d。olefin IMI的光解反应存在2条主要途径:一是羟基化生成4,5-二羟基化吡虫啉,该产物进一步氧化断裂药效基团硝基亚胺基生成羰基化产物;二是直接脱去硝基基团生成胍基产物。
A study was done on photic stability, photolytic dynamics and pathway of photolytic metabolism of olefin IMI. Results show that olefin IMI was stable in darkness. It decreased by 3% in concentration after having been kept in room temperature and darkness for 400 days. However in the laboratory under simulated sunlight, olefin IMI was unstable and easily degraded. Its photolytic reaction fitted the first-order kinetic equation （ r〉0.99 ）, and its half life was figured out to be 4 days. Its photolytic reaction followed two pathways, either through hydroxylation into 4,5-dihydroxy IMI, which is oxidized, breaking its nitroimine pharmacophore and turned into earbonyl product, or through formation of guanidine metabolites by breaking off nitroimine group.
出处
《生态与农村环境学报》
CAS
CSSCI
CSCD
北大核心
2009年第2期103-106,共4页
Journal of Ecology and Rural Environment
基金
环境保护部环保公益性行业专项(200809092)
