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; School of Advanced Agricultural Sciences, Weifang University, Weifang, Shandong, 261061, 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.
Chemosphere. 2024 Jul;359:142371. doi: 10.1016/j.chemosphere.2024.142371. Epub 2024 May 18.
Neonicotinoid insecticides (NNIs) have caused widespread contamination of multiple environmental media and posed a serious threat to ecosystem health by accidently injuring non-target species. This study collected samples of water, soil, and rice plant tissues in a water-soil-plant system of paddy fields after spaying imidacloprid (IMI), thiamethoxam (THM), and clothianidin (CLO) to analyze their distribution characteristics and migration procedures and to assess related dietary risks of rice consumption. In the paddy water, the concentrations of NNIs showed a dynamic change of increasing and then decreasing during about a month period, and the initial deposition of NNIs showed a trend of CLO (3.08 μg/L) > THM (2.74 μg/L) > IMI (0.97 μg/L). In paddy soil, the concentrations of the three NNIs ranged from 0.57 to 68.3 ng/g, with the highest residual concentration at 2 h after application, and the concentration trend was opposite to that in paddy water. The initial deposition amounts of IMI, THM, and CLO in the root system were 5.19, 3.02, and 5.24 μg/g, respectively, showing a gradual decrease over time. In the plant, the initial deposition amounts were 19.3, 9.36, and 52.6 μg/g for IMI, THM, and CLO, respectively, exhibiting concentration trends similar to those in the roots. Except for IMI in soil, the dissipation of the NNIs conformed to the first-order kinetic equation in paddy water, soil, and plant. The results of bioconcentration factors (BCFs) and translocation factor (TF) indicated that NNIs can be bi-directionally transported in plants through leaf absorption and root uptake. The risk of NNIs intake through rice consumption was low for all age groups, with a slightly higher risk of exposure in males than in females.
新烟碱类杀虫剂（NNIs）意外伤害非靶标物种，导致其在多种环境介质中广泛污染，对生态系统健康构成严重威胁。本研究采集了水稻田水土植物系统中吡虫啉（IMI）、噻虫嗪（THM）和噻虫胺（CLO）喷施后水、土和水稻植株组织的样本，分析了其分布特征和迁移过程，并评估了相关的稻米食用风险。在稻田水中，NNIs 的浓度在大约一个月的时间内表现出先增加后减少的动态变化，NNIs 的初始沉积呈现 CLO（3.08μg/L）>THM（2.74μg/L）>IMI（0.97μg/L）的趋势。在稻田土壤中，三种 NNIs 的浓度范围为 0.57-68.3ng/g，施药后 2h 时残留浓度最高，浓度趋势与稻田水相反。IMI、THM 和 CLO 在根系中的初始沉积量分别为 5.19、3.02 和 5.24μg/g，随着时间的推移逐渐减少。在植物中，IMI、THM 和 CLO 的初始沉积量分别为 19.3、9.36 和 52.6μg/g，浓度趋势与根系相似。除土壤中的 IMI 外，NNIs 在稻田水、土壤和植物中的消解均符合一级动力学方程。生物浓缩因子（BCFs）和转移因子（TF）的结果表明，NNIs 可以通过叶片吸收和根系吸收在植物中双向运输。各年龄段人群通过食用稻米摄入 NNIs 的风险均较低，男性的暴露风险略高于女性。
