Characterization of the photodegradation products of metolachlor: structural elucidation, potential toxicity and persistence.
Characterization of the photodegradation products of metolachlor: structural elucidation, potential toxicity and persistence.
复制标题
DOI：
10.1002/jms.3121
复制
发表时间：
2012-12
期刊：
影响因子：
--
通讯作者：
S. Coffinet;A. Rifai;C. Genty;Yasmine Souissi;S. Bourcier;M. Sablier;S. Bouchonnet
中科院分区：
文献类型：
--
作者：
S. Coffinet;A. Rifai;C. Genty;Yasmine Souissi;S. Bourcier;M. Sablier;S. Bouchonnet
用紫外可见辐射对异丙甲草胺和异丙甲草胺-d(6)水溶液进行光解。采用气相色谱-质谱联用电子-化学电离-多级质谱法对15种异丙甲草胺副产物进行了结构分析。异甲草胺的光解副产物主要是脱卤和羟基化反应，有时伴有环化反应。计算机毒性预测试验表明，某些光解产物的毒性预计将大于异丙甲草胺。持久性研究表明，副产物的相对丰度随辐照时间变化很大。还研究了溶液的光解后演化，以确定主要副产物的持久性。它允许确定大多数副产物可以在光解结束后12小时以上找到，这是一个非常值得关注的问题，因为在大多数工业过程中，处理后的水通常在处理后几个小时内即可使用。
Aqueous solutions of metolachlor and metolachlor-d(6) were photolyzed with UV-visible radiations. The structures of 15 by-products of metolachlor were determined through gas chromatography-mass spectrometry analyses using electron and chemical ionization combined with multistage mass spectrometry. The photolysis by-products of metolachlor resulted mainly from dehalogenation and hydroxylation, in some cases accompanied by cyclization. In silico tests for toxicity prediction showed that the toxicity of some photolysis products is expected to be greater than that of metolachlor. Persistence studies showed that the by-product relative abundances vary in large amounts with the irradiation time. The post-photolysis evolution of the solution was also studied, in order to determine the persistence of the main by-products. It allowed to establish that most of the by-products can be found more than 12 h after the end of the photolysis, which is of a great concern as treated water is generally available for consumption only a few hours after treatment in most of industrial processes.