2016~2020年济南市居民饮用水中8种重金属浓度变化趋势及健康风险特征分析

Concentration changes and health risk of 8 heavy metals in drinking water in Jinan from 2016 to 2020

目的探讨济南市城区和农村饮用水中重金属浓度的长期变化及慢性健康风险水平。方法 2016~2020年在济南市10个区县分别设置城区和农村饮用水监测点,采集饮用水样品,共计对2690份样品中的8种重金属[砷、镉、铬(六价)、铅、硒、铝、铜、锌]进行检测。参照《化学物质环境健康风险评估技术指南》(WS/T 777-2021),对3种重金属(砷、铅、铜)成人经口摄入途径导致的慢性健康风险进行评估,描述不同水样、不同水源、不同水期类型饮用水中3种重金属慢性健康风险的时间变化趋势,并分析不同处理措施饮用水中重金属慢性健康风险差异。结果 2016~2020年济南市饮用水中,8种重金属元素中有6种元素[砷、镉、铬(六价)、铅、铜、锌]浓度整体上均呈现出一定的降低趋势,其中铝(7/2 690,0.22%)和铅(3/2 690,0.11%)浓度存在超标情况。健康风险评估结果显示,砷同时存在致癌风险和非致癌风险,铅存在致癌风险,铜存在非致癌风险;城市饮用水中重金属污染的主要风险指标为砷、铅、铜,农村饮用水重金属污染的主要风险指标为砷;不同水样、不同水源、不同水期的饮用水健康风险均呈现下降趋势,不同水源类型水样砷致癌风险(P=0.016)、铅致癌风险(P<0.001)差异有统计学意义,经特殊处理的饮用水中砷致癌风险和铜非致癌风险有所降低。结论 2016~2020年济南市居民饮用水中大部分重金属元素浓度呈现出降低趋势,但砷、铅、铜仍然存在经口摄入途径暴露导致的长期慢性健康风险,应在今后饮水风险管理中给予重点关注。

Objective To investigate the long-term change of heavy metals concentration and chronic health risk in drinking water in urban and rural areas of Jinan. Methods From 2016 to 2020, the drinking water samples were collected in 10 districts and counties, and 8 heavy metals in 2,690 samples were analyzed, including arsenic, cadmium, chromium(hexagonal), lead, selenium, aluminum, copper and zinc. Based on the Technical Guidelines for Chemical Environmental Health Risk Assessment(WS/T 777-2021), the chronic health risks of the 3 heavy metals(arsenic, lead, copper) in drinking water intake exposure were analyzed. The characteristics of different water samples, water types, and water periods were described. Results Of the 8 heavy metals, 6 showed a descending trend, including arsenic, cadmium, chromium, lead, copper and zinc. Among them, the concentrations of aluminum(7/2 690, 0.22%) and lead(3/2 690, 0.11%) exceeded the national standards. Health risk assessment showed that arsenic had both carcinogenic and non-carcinogenic risks, lead had carcinogenic risk, and copper had non-carcinogenic risk. The main risk indicators of heavy metal pollution in urban drinking water were arsenic, lead and copper, and were arsenic in rural drinking water. The health risks of drinking water in different water samples, water types and water periods showed a downward trend. There were differences in arsenic carcinogenic risk(P=0.016) and lead carcinogenic risk(P<0.001) among different water types. The arsenic carcinogenic risk and copper non-carcinogenic risk in specially treated drinking water were reduced. Conclusion From 2016 to 2020, the concentrations of most heavy metals in the drinking water in Jinan showed a descending trend, but arsenic, lead and copper still had long-term chronic health risks and due attention should be paid to drinking water risk management.