International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, Heilongjiang 150030, China; Research Center for Eco-Environment Protection of Songhua River Basin, Northeast Agricultural University, Harbin, Heilongjiang 150030, China.
International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, Heilongjiang 150030, China; Research Center for Eco-Environment Protection of Songhua River Basin, Northeast Agricultural University, Harbin, Heilongjiang 150030, China.
J Environ Manage. 2023 Aug 1;339:117838. doi: 10.1016/j.jenvman.2023.117838. Epub 2023 Apr 5.
Extensive application of neonicotinoid insecticides (NNIs) in agricultural production has resulted in widespread contamination of multiple environmental media. To investigate the occurrence and fate of NNIs in the largest marsh distribution area in Northeast China, an integrated ecosystem covering farmlands, rivers, and marshes, referred to as the farmland-river-marsh continuum in this study, was chosen for soil, water, and sediment sampling. Five NNIs were detected, with imidacloprid (IMI), thiamethoxam (THM), and clothianidin (CLO) being the most frequently detected ones in different samples. Concentrations of target NNIs in soil, surface water, and sediment samples were 2.23-136 ng/g dry weight (dw), 3.20-51.7 ng/L, and 1.53-8.40 ng/g dw, respectively. In soils, NNIs were detected more often and at higher concentrations in upland fields, while the concentration of NNIs in the soybean-growing soils (71.5 ng/g dw) was significantly higher than in the rice-growing soils (18.5 ng/g dw) (p < 0.05). Total concentration of NNIs in surface water was lower in the Qixing River channel than inside the marsh, while that in sediments showed an opposite trend. Total migration mass of IMI from approximately 157,000 ha of farmland soil by surface runoff was estimated to be 2636-3402 kg from the application time to the sampling period. The storage of NNIs in sediments was estimated to range from 45.9 to 252 ng/cm. The estimated environmental risks, calculated as the risk quotients (RQs), revealed low risks to aquatic organisms (RQs <0.1) from the residual concentrations of NNIs in water.
大量使用新烟碱类杀虫剂（NNIs）在农业生产中导致了多种环境介质的广泛污染。为了调查 NNIs 在东北地区最大的沼泽分布区的发生和归宿，选择了一个涵盖农田、河流和沼泽的综合生态系统，即本研究中的农田-河流-沼泽连续体，进行土壤、水和沉积物采样。共检测到 5 种 NNIs，其中在不同样品中检测到的高频 NNIs 为吡虫啉（IMI）、噻虫嗪（THM）和噻虫啉（CLO）。土壤、地表水和沉积物样品中目标 NNIs 的浓度分别为 2.23-136ng/g 干重（dw）、3.20-51.7ng/L 和 1.53-8.40ng/g dw。在土壤中，旱地中 NNIs 的检出频率和浓度更高，而大豆种植土壤（71.5ng/g dw）中的 NNIs 浓度明显高于水稻种植土壤（18.5ng/g dw）（p<0.05）。七星河河道中地表水的 NNIs 总浓度低于沼泽内，而沉积物中的总浓度则呈现相反的趋势。通过地表径流从约 157000ha 农田土壤中估算出 IMl 的总迁移量为 2636-3402kg，从施药时间到采样期间。估计 NNIs 在沉积物中的储存量为 45.9-252ng/cm。根据风险商（RQs）计算的 NNIs 在水中残留浓度的环境风险估计值表明，对水生生物的风险较低（RQs<0.1）。
