秦皇岛市蔬菜中重金属污染状况及健康风险分析

Concentration analysis in vegetables ofQinhuangdao City and their health-threateninghazards assessment of heavy metals

为了了解秦皇岛市商品蔬菜中的重金属污染状况,分别对蔬菜市场5类37种蔬菜共计518份蔬菜样品中As、Cd、Cr、Cu、Ni、Pb、Zn7种重金属元素的污染状况和健康风险进行分析。结果表明,各类蔬菜中As、Cd、Cr、Cu、Ni、Pb、Zn的平均质量比分别为0.036 mg/kg、0.019mg/kg、0.079 mg/kg、0.491 mg/kg、0.104 mg/kg、0.035 mg/kg、2.632mg/kg,其中12.17%的蔬菜样品重金属质量比超过限量标准,Cd和Cr是主要的污染元素。各类蔬菜重金属综合污染指数均值为0.828±0.854,23.75%的蔬菜样品受到不同程度的污染,其中轻度污染占17.18%,中度污染占3.47%,重度污染占3.09%,处于警戒限的蔬菜占总体的16.22%;重金属污染程度以茎菜类最为严重(56.76%),其次为叶菜类(36.01%)。根据成人和儿童暴露人群健康风险级别将蔬菜分为3类:一类蔬菜成人健康风险率为29.37%,儿童健康风险率为37.84%;二类蔬菜成人健康风险率为0～9.95%,儿童健康风险率为6.67%～18.96%;三类蔬菜基本无暴露健康风险。各类蔬菜复合健康风险以Cd或Cr贡献率最大。儿童因摄食蔬菜导致的重金属健康风险大于成人。

The present paper is to introduce our heavy metal content analysis in the vegetables of Qinhuangdao City and the investigation findings of the health hazards to be brought about by such pollutants. In order to investigate the heavy metal pollution in the vegetables and provide a scientific implication for the food safety and environmental quality control, we have collected 5 categories of vegetable species including 37 kinds of 518 samples from Qinhuangdao greens markets. As a result, we have discovered the heavy metal contents like As, Cd, Cr, Cu, Ni, Pb and Zn in them. When comparing the actual contents of the heavy metal quotients in the samples to the standards of the national FAO/WHO vegetable health-protection indexes and the target hazard quotients （THQ）, we have made systematic analysis of the pollution situations and the likely health hazards to be brought about to the local residents. The results of our analysis can be shown as follows： The average content of As, Cd, Cr, Cu, Ni, Pb and Zn can be illustrated as 0.036 mg/kg, 0.019 mg/kg, 0.079 mg/kg, 0.491 mg/kg, 0.104 mg/kg, 0.035 mg/kg and 2.632 mg/kg respectively, of which about 12.17% of the samples were found exceeding the state-stipulating heavy-metal content limit, with Cd and Cr being the main contaminants. The heavy metal component pollution indexes account for 0.828±0.854, about 23.75% of the samples under discussion were subjected to different degrees of pollution, the mild pollution of which accounts for 17.18%, whereas the moderate one of which accounts for 3.47% and severe case accounts for 3.09%, with the 16.22% of the samples categorized into the warning category. If the pollution parts of the suffered vegetables are considered, the stems of the greens were polluted most heavily （56.76%）, followed by the leaves （36.01%）. If the health hazard degrees to be accounted for, 3 kinds of them for adult consumers and children consumers can be classified as： the first kind is estimated to bring about 29.37% of health hazards to adults and 37.84% of hazards to the children. And, for the second kind, it is likely to cause harm to the health of adults with a rate of 0-9.95%, while to the health of children with a risk hazard rate of 6.67%-18.96%. As to the third kind of vegetables, the health hazard rate both to adults and to children is estimated to be zero. And, finally, it has to be pointed out that the combined health hazard factors are mainly caused by the pollution of Cd and Cr, and greater health hazards to hit children tend to be more serious than to adults.