Jiangsu Engineering Laboratory for Environment Functional Materials, School of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an 223300, China.
Jiangsu Engineering Laboratory for Environment Functional Materials, School of Chemistry and Chemical Engineering, Huaiyin Normal University, Huai'an 223300, China.
Sci Total Environ. 2024 May 1;923:171455. doi: 10.1016/j.scitotenv.2024.171455. Epub 2024 Mar 2.
Neonicotinoid (NEO) insecticides have been frequently detected in natural aquatic environments. Nevertheless, the distribution of NEOs in artificial environments is not clear. The Beijing-Hangzhou Grand Canal is the longest canal in the world. The northern Jiangsu segment of the Grand Canal was selected to study the spatiotemporal variation and source of eight NEOs in the canal water and assess their ecological and health risks. The total NEO concentration in the canal water was 12-289 ng L in the dry season and 18-373 ng L in the wet season, which were within the concentration range in other 11 natural rivers worldwide. The average total NEO concentrations were not statistically different between the seasons; only the concentrations of imidaclothiz, thiacloprid (THI), acetamiprid, and dinotefuran were different. At city scale, the total NEO concentration in the dry season showed a decreasing trend along the water flow from Xuzhou City to Yangzhou City. The total NEO concentrations were found to be positively correlated with the sown area of farm crops and the rural labour force, indicating the agricultural influence on the spatial distribution of NEO concentrations. In the wet season, relatively high NEO concentrations were distributed in downstream sites under the influence of artificial regulation. The primary contributor to the NEO inputs into the canal was the nonpoint source in the dry and wet seasons, with a relative contribution of 68 %. THI, imidacloprid, clothianidin and thiamethoxan would produce chronic ecological risks in both seasons. Further consideration needs to be given to the above four NEOs and NEO mixtures. The human health risks that NEOs posed by drinking water were assessed based on the chronic daily intake (CDI). The maximum CDI for adults and children was lower than the reference doses. This suggested public health would not be at risk from canal water consumption.
新烟碱类（NEO）杀虫剂经常在自然水生环境中被检测到。然而，人工环境中 NEO 的分布情况尚不清楚。京杭大运河是世界上最长的运河。本研究选取了京杭大运河苏北段，研究了运河水中 8 种 NEO 的时空变化和来源，并评估了它们的生态和健康风险。在旱季，运河水中的总 NEO 浓度为 12-289ng/L，在雨季为 18-373ng/L，这一浓度范围与全球其他 11 条自然河流相当。季节间运河水中总 NEO 浓度没有统计学差异；仅噻虫啉、噻虫嗪（THI）、乙酰甲胺磷和噻虫胺的浓度有差异。在城市尺度上，旱季总 NEO 浓度沿水流从徐州市到扬州市呈下降趋势。总 NEO 浓度与农田播种面积和农村劳动力呈正相关，表明农业对 NEO 浓度空间分布的影响。在雨季，受人工调控影响，下游站点的 NEO 浓度相对较高。旱季和雨季 NEO 输入运河的主要来源是非点源，相对贡献率分别为 68%。THI、吡虫啉、噻虫啉和噻虫嗪在两个季节都会产生慢性生态风险。需要进一步考虑这四种 NEO 及其混合物。基于慢性日摄入量（CDI）评估了 NEO 通过饮用水对人体健康的风险。成人和儿童的最大 CDI 均低于参考剂量，这表明从运河水中摄入 NEO 不会对公众健康构成威胁。
