大连市饮用水中多环芳烃的概率致癌风险评价

Probabilistic cancer risk assessment of polycyclic aromatic hydrocarbons in drinking water in Dalian,China

饮用水中多环芳烃(PAHs)的水平及其致癌风险直接关系到居民的身体健康。考察了大连市饮用水中14种典型PAHs的质量浓度,并应用概率致癌风险分析方法评价饮用水中PAHs对不同年龄段和性别人群的致癌风险。结果表明:饮用水中基于苯并(a)芘的毒性当量为3.6ng/L,低于国家饮用水标准。对儿童和青年,饮用水中PAHs引起的累积概率为90%的致癌风险分别为6.2×10-7和7.4×10-7,低于美国环保局建议的致癌风险值10-6,且性别间的差异很小;对成年人,累积概率为90%的致癌风险为1.7×10-6,饮用水中PAHs对成年人具有潜在的致癌风险,并且女性大于男性。同时分析了影响概率致癌风险评价的主要因素,其中饮用水中PAHs毒性当量的变化对致癌风险评价结果影响最大。

Polycyclic aromatic hydrocarbons （PAHs） are ubiquitous carcinogenic pollutants in the environment. It is vital to monitor the levels of PAHs in drinking water and assess their cancer risks to human. This study investigated the concentrations of PAHs in drinking water in Dalian and estimated the incremental lifetime cancer risk （ILCR） of PAHs employing the probabilistic risk assessment. PAHs were detected in all the drinking water samples, however, benzo（a） pyrene （BaP） based Toxicity Equivalency Quantity （ TEQ ）, 3.6 ng/L, was lower than the national standard （10 ng/L）. The probabilistic cancer risk assessment demonstrated that the cancer risks of 90% cumulative probability for children and adolescents were lower than 10^-6, a standard proposed by the US EPA, indicating the cancer risks can be neglected. Whereas, the cancer risk for adults was 1.7×10^-6, implying potential cancer risk. Due to various body weights and daily habits, different cancer risks were observed between genders. For adults, the cancer risk for female was higher than male, while the differences were insignificant for children and adolescents. To identify the most influential parameters in probabilistic cancer risk assessment, sensitivity analysis was performed, which indicated that the most influential parameters were TEQ in drinking water and daily consumption amount of water.