饮用水系统中邻苯二甲酸酯的污染特征及健康风险评价

Contamination profiles and health risk assessment of phthalates in drinking water systems

邻苯二甲酸酯(PAEs)作为全球大规模使用的增塑剂,已成为环境中“无处不在”的一类新兴污染物.PAEs在世界各国饮用水中被广泛检出,但在饮用水输配系统中的污染特征及潜在污染来源研究尚不充分.本研究以饮用水系统为对象,分析了原水、出厂水及龙头水中PAEs的污染特征及变化规律,讨论了季节因素对各阶段出水中PAEs污染特征的影响,并评估了龙头水中PAEs对各类暴露人群所构成的健康风险.结果表明:原水中总PAEs浓度呈夏季>冬季>春季>秋季的规律,DBP、DEHP及DiBP是原水中主要存在的PAEs;水处理过程能去除47.9%~76.7%的总PAEs,对高分子量的DEHP去除率更高;龙头水中PAEs的浓度要显著高于出厂水,其中夏季最为明显,室内塑料管材是潜在的污染来源;龙头水中PAEs对人体健康造成的非致癌风险和致癌风险均低于最大可接受风险水平,对成年男性构成的致癌风险最高为7.37×10^(-7),已接近最大可接受风险水平(10^(-6)),应加以重视.

As widely used plasticizers,phthalates(PAEs)become ubiquitous emerging contaminants in the environment.PAEs are frequently detected in drinking water around the world,but the research on their contamination characteristics and potential sources in the drinking water distribution system is not sufficient.Therefore,aims at the whole drinking water system,and the contamination characteristics and changes of PAEs in raw water,finished water,and tap water were studied.The influence of seasonal factors on the contamination characteristics of PAEs in the effluent of each unit process was analyzed,followed by an assessment of the health risks posed by PAEs in tap water to various exposed contaminations.The results showed that the concentration of total PAEs in raw water was:summer>winter>spring>autumn,and DBP,DEHP,and DiBP were the primary PAEs present in raw water.The water treatment process can remove 47.9%~76.7%of total PAEs,with higher removal rates for high molecular weight DEHP.Levels of PAEs in tap water are significantly higher than those in finished water,most notably in summer,and indoor plastic pipes may be a potential source of contamination.Both the non-carcinogenic and carcinogenic risks posed by PAEs in tap water are below the maximum acceptable risk level,but the highest carcinogenic risk posed to adult males is 7.37×10^(-7),which is close to the maximum acceptable risk level(10^(-6))and should be paid attention to.