淄博市生活饮用水中硝酸盐暴露及其健康风险的时空分布特征

目的 对饮用水硝酸盐进行健康风险评估,为水质干预决策提供技术依据。 方法 对2016~2020年淄博市2 575份城乡饮用水样品检测硝酸盐含量,采用我国《化学物质环境健康风险评估技术指南》(WS/T 777-2021)的环境健康风险评价模型,分析不同年度、不同监测点类型、不同水源、不同处理方式的硝酸盐含量和非致癌健康风险的时空分布特征。 结果 2016~2020年共检测水样2 575份,硝酸盐超标率为10.76%。饮用水硝酸盐含量具有空间聚集性,高值主要集中在沂源县中部和东部、博山区西南部,低值集中在高青县和桓台县。饮用水硝酸盐含量和非致癌健康风险总体呈现逐年升高趋势,农村水高于城区水、地下水高于地表水、未处理水高于处理水。5年总体平均非致癌风险为0.21,对人体产生的非致癌风险较低;最高非致癌风险为1.99,主要集中在沂源县,对人体存在长期暴露的非致癌健康风险。 结论 淄博市局部区域饮用水硝酸盐污染较严重,存在非致癌健康风险,应引起关注并采取水质干预措施。

Spatiotemporal distribution characteristics of nitrates and health risks in drinking water in Zibo City

Objective To conduct health risk assessment of nitrate in drinking water, and provide technical basis for water quality intervention. Methods In 2016-2020, nitrate content in 2,575 urban and rural drinking water samples were tested. Based on "Technical Guidelines for Environmental Health Risk Assessment of Chemical Substances"(WS/T 777-2021), spatiotemporal distribution characteristics of nitrate content and non-carcinogenic health risks were analyzed in different years, types, water sources, and water treatment methods. Results A total of 2,575 water samples were tested in 2016-2020, and the exceeding standard rate of the nitrate was 10.76%. The nitrate content of drinking water was spatially agglomerated. The high values were mainly concentrated in the middle and east of Yiyuan County and the southwest of Boshan District, while the low values were concentrated in Gaoqing and Huantai Counties. Nitrate content and non-carcinogenic health risks of drinking water were generally increasing year by year, with rural water higher than urban water, groundwater higher than surface water, and untreated water higher than treated water. The 5-year overall average non-carcinogenic risk was 0.21, with the relatively low non-carcinogenic risk; the highest non-carcinogenic risk was 1.99, and the areas with the highest non-carcinogenic risk value higher than 1 were mainly concentrated in Yiyuan County, which has long-term non-carcinogenic risk to humans. Conclusion Nitrate pollution in drinking water is serious in some areas of Zibo City, and there is a non-carcinogenic health risk. It should be paid attention to and water quality intervention measures should be taken.