准东煤矿区土壤镉污染风险评价及敏感性分析

镉是一种毒性很强的重金属元素,易通过食物链进入人体,对人体健康产生影响。新疆地区的煤炭资源开发已引起重金属污染问题,但目前有关镉污染风险评价的研究相对不足。本研究采用地质累积指数法、潜在生态危害指数法、美国环保局(US EPA)健康风险评估方法和缓冲区分析方法,对准东红沙泉和北山煤矿土壤中镉的污染现状、生态风险水平和健康风险水平做了分析与评价。结果显示:1)研究区土壤镉含量普遍超过国家土壤环境质量Ⅱ级标准,处于重污染水平;2)研究区的镉污染具有极高生态风险;3)镉污染水平和生态风险系数具有明显空间性,它们在研究区的强度排序为堆煤场矿区生活区芨芨湖雀仁乡;4)手-口途径是最主要的健康风险暴露途径,所有人群中儿童暴露风险最高;5)准东煤矿区镉污染水平较高,但其非致癌水平和致癌水平均未超过风险限值;6)矿区周边0~30 km区域内属于健康风险高敏感区域。综上可知:准东地区煤矿开采引起了周边环境镉污染。镉污染对人类健康,特别是儿童的健康具有较高的暴露风险。当地镉污染虽未达到致病水平,但也应引起足够重视。

Human Health Risk Assessment and Environmental Sensitivity Analysis of Soil Cadmium Pollution in Zhundong Mine Region of East Junggar Basin in Xinjiang, China

Cadmium (Cd) is a highly toxic heavy metal element, which can affect human health through the ampli-fication via food chain. The development of mineral resources produces a series of problems of heavy metal pollu-tion in Zhundong Region of Xinjiang, China. However, the health risk assessment of Cd element remains unclear. In this study, the geo-accumulation index, the methods of potential ecological risk assessment, health risk assess-ment of USA EPA, and the spatial statistical analysis were used to investigate and evaluate the pollution situation, the ecological risk and human health risk of Cd in the Hongshaquan and Beishan coal mining areas of Zhundong Region of Xinjiang, China. The results showed that:1) Cd contents in soil of Zhundong Region were higher than that of the second level of national heavy metal pollution standard. Zhundong Region has the high Cd pollution level. 2) Ecological risk (RI) and geoaccumulation index (Igeo ) show that Cd pollution was extremely strong with high ecological risk in the study area. 3) Cd pollution level and ecological risk showed obvious spatial heterogenei-ty, with their contents sorted by the coal yard >residential quarters of mining area>Jijihu Village>Queren Town. 4) The intake by mouth and hand was the most common way of Cd exposure. Children have the highest risk of Cd exposure among people. 5) The results of human health risk assessment showed that Cd content was less than the carcinogenic limit values of Cd pollution in study region. 6) 0-30 km around the mining area was a high sensitive region of Cd against human health. In conclusion, the development of mineral resources produces Cd pollution in Zhundong Region of Xinjiang. Then this pollution already affected human health and imposed the highest risk of Cd exposure to children. Although Cd content was less than the carcinogenic limit values of Cd pollution, the local government departments should develop some strategies to control Cd pollution.