湖北大冶铜绿山矿区蔬菜重金属污染特征及健康风险研究

为了解湖北大冶铜绿山矿山周围地区土壤、蔬菜中Cd、Cu、Pb和As的含量水平、富集能力及通过蔬菜摄入导致的人群健康风险，采用对应采样方法采集矿山周围土壤、蔬菜样品共104件，利用ICP-MS测定上述样品中Cd、Cu、Pb和As的含量，通过综合质量评价法、富集系数和目标危险系数对研究区土壤-蔬菜系统中重金属的污染状况、富集能力及人群暴露的健康风险进行了分析。结果表明:研究区土壤重金属污染严重，Cd、Cu、Pb和As平均含量分别达2.56、363.23、121.25和35.96 mg/kg，分别为湖北省对应元素土壤背景值的15.06、11.83、4.54和2.92倍，表现为以Cd、Cu为主的多种重金属共同污染。与《食品中污染物限量》（GB2762 2012）标准比较，蔬菜中Cd、Cu和Pb含量的样本超标率分别为40%、6%和2%，而As的含量均不超标。土壤-蔬菜系统中重金属的综合质量指数达9.76，为重度污染。蔬菜中重金属富集能力的排序为：Cd > Cu > As > Pb，叶菜类蔬菜对Cd、Cu、As和Pb的富集系数均高于非叶菜类蔬菜。研究区人群通过蔬菜摄入As的目标危险系数均大于1，存在As暴露的健康风险；成人和儿童食用蔬菜而摄入重金属的总体目标危险系数分别为1.71~3.98和2.20~5.10，儿童比成人遭受的健康风险更大，并且距离矿山越近，所遭受的健康风险越大。蔬菜中重金属的复合污染已使大冶铜绿山矿山周围居民面临潜在的健康风险。 关键词： 铜绿山；蔬菜；重金属；健康风险；大冶

Contamination Characteristics and Health Risk for Heavy Metals via Consumption of Vegetables Grown in Regions Affected by Tonglvshan Mine in Hubei,China

To understand the soil heavy metal pollutions nearby the Tonglvshan mine,Daye city (Hubei province,China),the soil samples and eight types of vegetables were analyzed with their Cd,Cu,Pb and As concentrations from seven sampling sites around the mine,the heavy metals'biomagnifications and the potential risks to people's health were also evaluated in this study. Heavy metals were analyzed by ICP-MS,the biomagnification and health evaluation were performed by bio-concentration factor (BCF),Influence index of comprehensive quality (IICQ),and target hazard quotient (THQ). The results showed the soil samples have been seriously contaminated,the mean concentrations of Cd,Cu,Pb and As in soils recorded as 2. 56 mg /kg,363. 23 mg /kg,121. 25 mg /kg and 35. 96 mg /kg,respectively; these were 15. 06,11. 83,4. 54 and 2. 92 times of the provincial soil averaged backgrounds,respectively. Compared with the National Foods Contaminants Limits (GB2762-2012),the vegetables Cd,Cu and Pb concentrations were higher than the limits 40％,6％ and2％,respectively,whereas the As concentrations fall within the National limit. The BCF values of soil and vegetables followed with the order of Cd ＞ Cu ＞ As ＞ Pb,and the heavy metals BCF values in the leafy vegetables were all higher than the non-leafy vegetables. The IICQ of the soil-vegetable system was calculated as9. 76,which accounted for critical heavy metals pollutions. People's might be exposed to the As pollutions through the consumption of those polluted vegetables,as the THQ of As via vegetable consumption was higher than 1. The total heavy metals THQs for adult and child were 1. 71 ～ 3. 98 and 2. 20 ～ 5. 10,respectively. The people living around the Tonglvshan mine were suffering health risks through the heavy metal polluted vegetables.