Eawag: Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland.
Center for Primary Care and Public Health (Unisanté), University of Lausanne, 1066, Epalinges-Lausanne, Switzerland.
Environ Sci Pollut Res Int. 2023 Jan;30(4):10312-10328. doi: 10.1007/s11356-022-22717-2. Epub 2022 Sep 8.
Pesticides are intensely used in the agricultural sector worldwide including smallholder farming. Poor pesticide use practices in this agronomic setting are well documented and may impair the quality of water resources. However, empirical data on pesticide occurrence in water bodies of tropical smallholder agriculture is scarce. Many available data are focusing on apolar organochlorine compounds which are globally banned. We address this gap by studying the occurrence of a broad range of more modern pesticides in an agricultural watershed in Uganda. During 2.5 months of the rainy season in 2017, three passive sampler systems were deployed at five locations in River Mayanja to collect 14 days of composite samples. Grab samples were taken from drinking water resources. In these samples, 27 compounds out of 265 organic pesticides including 60 transformation products were detected. In the drinking water resources, we detected eight pesticides and two insecticide transformation products in low concentrations between 1 and 50 ng/L. Also, in the small streams and open fetch ponds, detected concentrations were generally low with a few exceptions for the herbicide 2,4-D and the fungicide carbendazim exceeding 1 ug/L. The widespread occurrence of chlorpyrifos posed the largest risk for macroinvertebrates. The extensive detection of this compound and its transformation product 3,4,5-trichloro-2-pyridinol was unexpected and called for a better understanding of the use and fate of this pesticide.
农药在全球范围内，包括小农农业在内的农业部门都被大量使用。在这种农业环境中，农药使用不当的情况有很多记载，并可能会损害水资源的质量。然而，关于热带小农农业水体中农药存在的数据却很少。许多现有数据都集中在全球禁用的非极性有机氯化合物上。为了解决这一差距，我们研究了在乌干达一个农业流域中广泛存在的各种新型农药。在 2017 年雨季的 2.5 个月中，在 River Mayanja 的五个地点部署了三个被动采样系统，以收集 14 天的复合样本。从饮用水资源中采集了随机样本。在这些样本中，检测到 265 种有机农药中的 27 种化合物，包括 60 种转化产物。在饮用水资源中，我们检测到 8 种农药和 2 种杀虫剂转化产物，浓度较低，在 1 至 50ng/L 之间。此外，在小溪和开放的取水池塘中，除了除草剂 2,4-D 和杀菌剂多菌灵的浓度超过 1ug/L 外，检测到的浓度通常较低。氯吡硫磷的广泛存在对大型无脊椎动物构成了最大的风险。这种化合物及其转化产物 3,4,5-三氯-2-吡啶醇的广泛检测出人意料，需要更好地了解这种农药的使用和命运。
