煤矿区大气降尘中Hg和As的赋存形态及健康风险评价

Speciation characteristics and health risk assessment of Hg and As in atmospheric deposition from coal mine area

对宿州煤矿区大气降尘中Hg和As的含量特征及赋存形态进行分析,并利用健康风险评价模型,评估其在多暴露途径下对人体的健康风险。结果表明:宿州煤矿区大气降尘中Hg和As的平均含量分别为土壤背景值的19.91和1.54倍,前者为偏重污染,后者介于无污染至轻度污染;降尘中Hg和As均以残渣态形式为主,生物可利用程度较低,但Hg元素具有较高的潜在生物危害性;As经手口摄入分别是引发大气降尘重金属非致癌健康风险的主要元素和暴露途径,儿童的非致癌风险(0.903)高于成人(0.122),但均低于美国EPA的风险限值1.0;降尘中As通过呼吸吸入途径不具有致癌风险。

The contents and speciation characteristics of Hg and As in the atmospheric deposition from Suzhou coal mine area were analyzed,and then the health risk of Hg and As were assessed by Health Risk Model. The results showed that the average contents of Hg and As in the atmospheric deposition were 19.91 and 1. 54 times over the soil background value of China. Hg was at moderate to heavy pollution level,while As was at no to light pollution level; Both Hg and As were mainly dominated by the residual form,reflecting weaker bioavailability of the two elements,but Hg has higher potential biotoxicity; To the non-cancer hazard risk,hand-mouth ingestion was the main route of exposure and As was the main element. The non-cancer hazard risk of children（0.903）was higher than adult（ 0. 122）,but they were all lower than the limited risk value（ 1. 0） of USEPA; The carcinogenic risks of As was also lower than the limited value（ 10～（-6）～ 10～（-4））,suggesting that it was no harm to health.