农药在环境中的水解机理及其影响因子研究进展

农药的水降解与其在环境中的持久性是密切相关的,它是影响农药在环境中的归宿机制的重要依据之一,也是评价农药在水体中残留特性的重要指标。近些年来,国内外不少学者对农药尤其是有机磷、氨基甲酸酯、拟除虫菊酯和磺酰脲类等的水解进行了大量研究,其内容涉及到农药水化学降解机理及其各种因子如pH值、温度和黏土矿物等对农药水解的影响等,并取得了很多新的进展。但是所有这些研究主要集中于实验室内,而对其自然环境中各因子的贡献及其水解机制的了解则相对较少。今后应加强农药在自然条件下的水解动力学与机理以及黏土矿物和腐殖酸对农药在水体中的催化水解研究,以更好地评价农药在环境中的行为与归宿,为农药的合理使用提高科学依据。

Hydrolysis and its influencing factors of pesticides in environment: a review

Hydrolysis of pesticides had close relationships with persistence of pesticides in the environments, and was both one of the important factors influencing the fate of pesticides in environments and important index for assessing pesticides residue persistence in aqueous systems. In the recent years, hydrolyses of pesticides such as organophosphates, carbamates, pyrethroids and sulfony- lureas were studied by scientists from home and abroad, which involved in hydrolysis mechanisms of pesticides in environments and their environmental factors such as pH, temperatures and clay minerals influencing the hydrolysis, and some achievements were made. However, most of studies on hydrolysis of pesticides were carried out in the laboratory, and little information was available about the degradation mechanisms of pesticides in the natural field conditions. Therefore, both hydrolysis kinetics and pathways of pesticides in the field, and catalytic degradation by clay and humus substances in water should be enhanced in order to better assess the behavior and fate of pesticides.