唐河地下水有机氯农药(OCPs)的分布特征及风险评估

为评估雄安新区唐河污水库周边地下水有机氯农药(OCPs)污染状况, 对2019年采集的36个地下水样品中OCPs进行分析, 初步确定六氯环己烷(HCHs)和双对氯苯基三氯乙烷(DDTs)的组成特征和来源, 并对其健康风险进行评价。结果表明: 1) 唐河地下水OCPs污染程度较轻, OCPs总量为nd~45.60 ng/L, 检出率为77.78%, HCHs贡献最大, 与 2018 年完成的唐河污水库一期生态治理工程有关; 2) 唐河地下水中 HCHs和DDTs主要来自历史残留, HCHs主要来源于农业, DDTs在地下水体中主要产生好氧代谢产物DDE; 3) 唐河地下水OCPs致癌风险与非致癌风险均较低, 婴儿为敏感受体, 总体上对人体健康不构成威胁。

Distributions and Risk Assessment of Organochlorine Pesticides (OCPs) in Tanghe Groundwater

In order to evaluate the pollution status of organochlorine pesticides (OCPs) in the groundwater around Tanghe Wastewater Reservoir in Xiong’an New area, the authors analyzed OCPs residues in 36 groundwater samples collected in 2019. The composition characteristics and sources of HCHs and DDTs were preliminarily determined, and their health risks were assessed. The results suggested that Tanghe groundwater showed lower OCPs pollution with total amount of nd–45.60 ng/L and a detection rate of 77.78%, of which HCHs was the greatest distributor. The lower OCPs contents were partially attributed to implementations of the ecological sewage treatment project in 2018. Furthermore, both HCHs and DDTs were mainly historical residues originated from agricultural source, and DDTs probably decomposed into aerobic metabolite DDE. Overall, the noncarcinogenic and carcinogenic risks of OCPs were very low, posing no threat to human health though infants were more sensitive.