State Agriculture Ministry Laboratory of Quality & Safety Risk Assessment for Tobacco, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
State Agriculture Ministry Laboratory of Quality & Safety Risk Assessment for Tobacco, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.
Ecotoxicol Environ Saf. 2020 Mar 15;191:110234. doi: 10.1016/j.ecoenv.2020.110234. Epub 2020 Jan 29.
Imidacloprid is a widely used neonicotinoid insecticide worldwide, and has attracted great concerns due to its potential threat to human and environment. Much effort was thus spent on developing the effective way for removing imidacloprid from water, but might also produce various degradation products with unknown risks. The hypothesis was then proposed that permanganate oxidation was probably the appropriate tool for eliminating imidacloprid and its toxicity through selective oxidation of specific groups. To that end, we studied the kinetics of permanganate/imidacloprid reaction by considering the effects of pH (5.0-9.0), temperature (15-35 °C), ionization strength (0.05-0.20 M), typical anions (Cl, Br, I) and humic acid. Based on the identified products from mass spectrometer, the main reaction pathway was found to be the hydroxylation of C-H bond at imidazole ring, leading to the decreased toxicity evaluated by ECOSAR program. Our results demonstrate that permanganate oxidation should be a very promising technique for controlling imidacloprid contamination by effective detoxification through highly selective partial oxidation. Moreover, this study has also paved the way toward applying permanganate oxidation for in situ chemical remediation of imidacloprid, though the corresponding standards need to be established in advance.
吡虫啉是一种在全球范围内广泛使用的新烟碱类杀虫剂，由于其对人类和环境的潜在威胁而引起了极大的关注。因此，人们投入了大量精力来开发从水中去除吡虫啉的有效方法，但这也可能产生具有未知风险的各种降解产物。于是提出了这样一种假设，即高锰酸盐氧化可能是通过选择性氧化特定基团来消除吡虫啉及其毒性的合适工具。为此，我们通过考虑 pH 值（5.0-9.0）、温度（15-35°C）、离子强度（0.05-0.20 M）、典型阴离子（Cl、Br、I）和腐殖酸的影响，研究了高锰酸盐/吡虫啉反应的动力学。根据质谱仪鉴定的产物，主要反应途径被发现是咪唑环上 C-H 键的羟化，导致毒性降低，这是通过 ECOSAR 程序评估的。我们的结果表明，高锰酸盐氧化应该是一种非常有前途的技术，通过高度选择性的部分氧化进行有效的解毒，从而控制吡虫啉的污染。此外，尽管需要事先建立相应的标准，但本研究也为在原位化学修复吡虫啉方面应用高锰酸盐氧化铺平了道路。
