宁波土壤中多环芳烃的健康风险评价

Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Soils of Ningbo Area,China

以宁波地区土壤中多环芳烃的含量调查结果为基础,采用美国能源部风险评估信息系统的暴露量化方法和美国环保局健康风险评估手册的风险表征方法,评估了土壤中16种多环芳烃对户外劳作者的健康风险。结果表明,宁波户外劳作者由于土壤中多环芳烃引起的平均非致癌危害指数为1.09×10-5,平均致癌风险值为3.17×10-7,可判定对人体健康的危害较小。宁波地区致癌多环芳烃含量最高暴露点致癌风险值为1.45×10-6,没有超过致癌风险水平上限(10-4),说明致癌风险尚在可接受范围内。多环芳烃中苯并(a)芘对综合致癌风险贡献最大,贡献率高达65.6%,应注意防范土壤中该污染物引起的健康危害。宁波户外劳作者受到的非致癌危害和致癌风险主要由直接摄入途径和皮肤接触途径贡献,两种途径对非致癌危害和致癌风险贡献率分别达到89%和100%,呼吸摄入引起的非致癌危害和致癌风险则相对较小。

Based on the monitoring data of polycyclic aromatic hydrocarbons（PAHs） in soils from 134 sampling points located in Ningbo,health risk assessment of PAHs for outdoor workers was evaluated,using the method of exposure assessment of Risk Assessment Information System from USA Energy Department and risk equation of Human Health Evaluation Manual of USEPA.The results showed that PAHs in the soils had little risk on human health,since the average noncancer hazard index and the average cancer risk for outdoor workers was 1.09×10-5 and 3.17×10-7 respectively;and the cancer risk of maximum exposure to carcinogenic PAHs for the workers was 1.45×10-6,which was less than the upper limit of acceptable cancer risk of 10-4.However,great attention to the benzo（a） pyrene and dibenzo（a,h） anthracene pollution in the soil should be paid because their contribution rates to the total cancer risk were 65.6% and 20%.Direct ingestion and dermal contact pathways mainly contributed to the noncancer hazard and cancer risk to the outdoor workers,by the reason of their high contribution rates for the noncancer hazard and cancer risk which were as high as 89% and nearly 100% respectively,while direct inhalation pathway relatively brought about very low risk for health.