本研究以平度市典型金矿区农田土壤-玉米系统为研究对象,采用地累积指数法和内梅罗指数法评价农田土壤重金属污染生态风险,采用靶标危害系数法评价重金属人体健康风险.结果表明,研究区农田土壤中4种重金属潜在风险程度为:Cd>Zn>Pb>Cr,均表现出中等及以上污染风险,其中Cd呈极严重污染风险;采样点的农田土壤重金属综合污染均处于轻度以上污染程度,其中一半以上处于中等以上污染等级.矿区居民经玉米途径摄入的单一重金属元素对健康的损害风险不大;4种重金属叠加的总危害指数分别是2.99×10-3(成人)和7.13×10-3(儿童),摄食玉米后,矿区居民可能遭受一定的健康风险危害,其中Cd贡献率最高(60.30%),且对儿童造成的健康风险明显高于成年人.%Heavy metals pollution in agricultural soils easily occur in the gold mining area and thereby negatively impact ecosystem and human health. Therefore, this study selected the soil-maize system in the typical gold mining area of Pingdu City as the case study. The ecological risk of heavy metals in farmland soil was evaluated using geo-accumulation index method and Nemero index method. Human health risk was evaluated using target hazard quotients(THQ)method.The results showed that the potential ecological risk of the four heavy metals in agricultural soils had an order of Cd>Zn>Pb>Cr, which potentially induced mediate risk and/or above. Thereinto, the potential ecological risk of Cd was extremely heavy.The integrated pollution risk levels of the four heavy metals were all light and/or above.Thereinto, the integrated pollution risk levels of the four heavy metals in the half of the sampling sites potentially were medium and/or above. The potential health risk of a heavy metal(Cd,Zn,Pb or Cr)was low to residents in the studied area when they ate maize and their products. However,there was a certain level of the integrated potential health risk,considering the total hazard index of 2.99×10-3for adults and 7.13× 10-3for children.Cd contributed the most to the integrated potential health risk,with a contribution of 60.30%.The integrated potential health risk of the four heavy metals was greater to children than adults.
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