豫北某市农村地下水污染特征及健康风险评价

Characteristics and health risk assessment of groundwater pollution in rural area ofa city in Northern Henan Province

目的 分析豫北某市农村地下水污染状况及健康风险,为改善农村生态环境、促进农业农村现代化建设提供科学依据。方法 2021年1—12月通过采集研究区域内民井及家用自来水共294份样品,检测水样中的39项指标,利用SPSS24.0软件分析农村地下水水质特征、污染状况、主要污染因子间的相关性及来源,结合美国环境保护署(U.S. Enviromental Protection Agency,USEPA)评价模型进行健康风险评估。结果 豫北某市农村地下水中总硬度、溶解性总固体、硫酸盐、氯化物、锰、耗氧量、钠、氟化物、碘化物及菌落总数共10项指标存在不同程度的超出GB/T 14848—2017《地下水质量标准》Ⅲ类标准限值,且总硬度、溶解性总固体、硫酸盐、氯化物、锰、钠、氟化物及菌落总数共8项指标超过GB 5749—2022《生活饮用水卫生标准》规定的限值。其余29项指标均优于或符合GB/T 14848—2017《地下水质量标准》Ⅲ类标准限值。锰、碘化物和菌落总数变异系数较大,分别为2.00、1.25和2.16,主要受人类活动影响。总硬度、溶解性总固体、硫酸盐、氯化物具有同源性,主要受区域地层因素、水文地质条件和水文地球化学因素影响。锰对成年人和未成年人人体健康的危害性均较小,通过经口摄入途径的量在人体可接受剂量范围内;氟的样本高值点对人体健康的危害性较大,超出通过经口摄入途径人体可接受剂量,对于未成年人的慢性健康风险(HQ_(max)=1.613)是成年人(HQ_(max)=1.145)的1.4倍,未成年人承担的人体健康风险(D_(max)=0.097)是成年人(D_(max)=0.069)的1.5倍。结论 氟应该作为该地区农村地下水生态环境治理的重点对象,需引起相关部门注意,采取相关措施,加强农村地下水水质治理,改善农村生态环境。

Objective To analyze the status and health risk of groundwater pollution in rural area of a city in Northern Henan Province,provide scientific basis for improving rural ecological environment and promoting agricultural and rural modernization.Methods From January to December 2021,294 samples of private wells and domestic tap water in the study area were collected,and 39 indicators were tested.The correlation and sources among rural groundwater quality characteristics,pollution status and main pollution factors were analyzed by SPSS 24.0 software,and the health risk assessment was carried out based on the evaluation model of U.S.Enviromental Protection Agency(USEPA).Results 10 indexes of total hardness,soluble total solids,sulfate,chloride,manganese,oxygen consumption,sodium,fluoride,iodide and total number of colonies in the rural groundwater in the study area exceeded the ClassⅢstandard limit of Groundwater Quality Standard(GB/T 14848-2017)to varying degrees.Eight indexes of total hardness,soluble total solids,sulfate,chloride,manganese,sodium,fluoride and total number of colonies exceeded the limit value specified in the Sanitary Standard for Drinking Water(GB 5749-2022).The other 29 indexes were better than or in line with the ClassⅢstandard limit of the Groundwater Quality Standard(GB/T 14848-2017).The coefficients of variation of manganese,iodide and total colony were 2.00,1.25 and 2.16,respectively,which was mainly affected by human activities.The total hardness,soluble total solids,sulfate and chloride are homologous,which were mainly affected by regional stratigraphic factors,hydrogeological conditions and hydrogeochemical factors.The manganese was less harmful to the human health of adults and minors,and the amount of oral ingestion was within the acceptable range of human dose.The sample high value point of fluorine was more harmful to the human health of adults and minors,which exceeded the acceptable dose of oral ingestion,the chronic health risk of minors(HQ_(max)=1.613)was 1.4 times that of adults(HQ_(max)=1.145),while the human health risk of minors(D_(max)=0.097)was 1.5 times that of adults(D_(max)=0.069).Conclusion The fluorine should be taken as the key object of rural groundwater ecological environment control in this area,it is necessary to attract the attention of relevant departments,take relevant measures to strengthen the rural groundwater quality control,and improve the rural ecological environment.