The unintended release of chemicals to the environment has led to global concern on water quality prompting widespread research on the occurrence of these compounds in water. While increasing information on organic micropollutants (OMPs) in European water resources is available, there is still limited information on the occurrence of OMPs in African water systems. In this study, a multi-residue analysis covering 428 chemicals using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) was performed on water samples collected from 48 surface water sites within the Lake Victoria South Basin, Kenya. A total of 75 compounds including pharmaceuticals, personal care products (PPCPs), pesticides, and industrial chemicals were detected and an additional three compounds (nevirapine, lamivudine and adenosine) were identified through suspect screening. Four compounds including diphenhydramine, simazine, triethylphosphate and acetyl-sulfamethoxazole (A-SMX) were detected in >80% of the sites showing their ubiquitous nature in the study area. Individual compound concentrations were detected up to 24 μg L-1. Concentrations above 1 μg L-1 were also reported for triethylcitrate, N-ethyl-o-toluenesulfonamide, hexazinone, nevirapine, adenosine and carbendazim. While crustaceans were potentially the taxon at risk for acute toxicity (toxic unit (TU) up to 2) with diazinon driving this risk, lower but substantial acute risk (TU 0.5) was observed for algae. Chronic risks were observed in 11 sites for algae (TU > 0.02) and in 5 sites for fish (TU > 0.01). A total of 16 compounds were prioritized based on frequency and extent of the exceedance of thresholds for acute and chronic risks to algae, crustaceans and fish and another 7 compounds prioritized by applying lowest Predicted No-Effect Concentrations (PNEC). Based on these indicators, this study provides candidate priority compounds for monitoring, assessment and abatement in western Kenya.

中文翻译：

---

肯尼亚维多利亚湖南盆地内淡水系统中有机微量污染物的发生和风险评估。

化学品意外释放到环境中已引起全球对水质的关注，促使人们对水中这些化合物的存在进行了广泛的研究。尽管可以获取有关欧洲水资源中有机微污染物（OMPs）的信息越来越多，但是有关非洲水系统中OMPs发生的信息仍然有限。在这项研究中，对从肯尼亚维多利亚湖南盆地内48个地表水站点收集的水样进行了液相色谱-高分辨率质谱法（LC-HRMS）涵盖428种化学物质的多残留分析。总共检测到75种化合物，包括药品，个人护理产品（PPCP），农药和工业化学品，另外还有3种化合物（奈韦拉平，拉米夫定和腺苷通过可疑筛查得以鉴定。在超过80％的位置检测到四种化合物，包括苯海拉明，辛嗪，磷酸三乙酯和乙酰基磺胺甲基恶唑（A-SMX），显示了它们在研究区域中的普遍存在。检测到的单个化合物浓度最高为24μgL-1。还报道了柠檬酸三乙酯，N-乙基邻甲苯磺酰胺，六嗪酮，奈韦拉平，腺苷和多菌灵的浓度高于1μgL-1。尽管甲壳类动物可能是具有急性毒性风险的分类单元（毒性单位（TU）最高为2），而二嗪农驱动了该风险，但藻类的急性风险却较低，但很大（TU 0.5）。在11个藻类场所（TU> 0.02）和5个鱼类场所（TU> 0.01）中发现了慢性风险。根据超出藻类，甲壳类和鱼类急性和慢性危险阈值的频率和程度，对总共16种化合物进行了优先排序，并通过应用最低的预测无效浓度（PNEC）对其他7种化合物进行了优先排序。基于这些指标，本研究为肯尼亚西部的监测，评估和减排提供了优先考虑的候选化合物。