Department of Civil, Architectural and Environmental Engineering and Environmental Research Center, Missouri University of Science and Technology, Rolla, Missouri 65409, USA.
J Agric Food Chem. 2010 Jun 9;58(11):6895-9. doi: 10.1021/jf100872f.
Fipronil, a pesticide gaining wide usage, was oxidized with common drinking water treatment disinfectants and oxidants; with a degradate identified using liquid chromatography-mass spectrometry. Oxidants investigated were free chlorine (HOCl/OCl(-)), monochloramine (ClNH(2)), chlorine dioxide (ClO(2)), and permanganate (MnO(4)(-)) at pH 6.6 and 8.6. Free chlorine, chlorine dioxide, and permanganate were reactive with fipronil to various degrees, whereas monochloramine was only marginally reactive. No oxidation products were observed for free chlorine, monochloramine, or chlorine dioxide. Oxidation by permanganate produced an identifiable degradate, fipronil sulfone, which was recalcitrant to further oxidation by permanganate. Fipronil sulfone could, however, be further degraded by free chlorine. Under typical conditions of water treatment, free chlorine was an effective oxidant for fipronil and fipronil sulfone, achieving partial removal at typical conditions. pH effects were observed for free chlorine, chlorine dioxide, and permanganate with more rapid oxidation occurring at pH 8.6 than at pH 6.6.
氟虫腈是一种广泛使用的杀虫剂，它与常见的饮用水处理消毒剂和氧化剂发生氧化反应，并使用液相色谱-质谱法鉴定出一种降解产物。研究的氧化剂包括自由氯（HOCl/OCl(-)）、一氯胺（ClNH(2)）、二氧化氯（ClO(2)）和高锰酸盐（MnO(4)(-)），在 pH 值为 6.6 和 8.6 时进行实验。自由氯、二氧化氯和高锰酸盐对氟虫腈的反应程度不同，而一氯胺的反应性则较低。自由氯、一氯胺或二氧化氯都没有观察到氧化产物。高锰酸盐氧化产生了可识别的降解产物氟虫腈砜，它对高锰酸盐的进一步氧化具有抗降解性。然而，氟虫腈砜可以被自由氯进一步降解。在典型的水处理条件下，自由氯是氟虫腈和氟虫腈砜的有效氧化剂，在典型条件下可实现部分去除。自由氯、二氧化氯和高锰酸盐的 pH 值效应明显，在 pH 值为 8.6 时的氧化速度比 pH 值为 6.6 时快。
