渭河陕西段水体重金属的分布特征及其健康风险

Distribution and health risk of heavy metals of Weihe River in Shaanxi Region

为了解2016年渭河陕西段综合治理全线贯通以后水体重金属的污染状况,文章采用重金属综合污染指数法和USEPA健康风险评价模型等,研究了渭河陕西段水体14种重金属的浓度水平、分布特征及其健康风险。结果表明,2016年渭河陕西段水体As浓度在皂河入渭处超过《地表水环境质量标准:GB3838—2002》Ⅲ类水质标准限值0.3倍,其余13种重金属浓度较低;各重金属空间分布差异较大,其综合污染处于可接受水平,行政区综合污染水平为渭南市>宝鸡市>西安市>咸阳市;As对周围居民产生的健康风险较大,是渭河水体重金属对沿岸居民产生健康风险的首要贡献源,应优先控制。

In order to understand the pollution status of heavy metals of Weihe River in Shaanxi Region after the comprehensive treatments of all sections in 2016, the concentration levels, distribution characteristics and health risks of 14 heavy metals were studied by using a Heavy Metal Pollution Index(HPI) and the Human Health Risk Assessment method recommended by the United States Environmental Protection Agency(USEPA). The results indicated that the arsenic exceeded the standard limit for category Ⅲ in surface water by 0.3 times of Zaohe River according to the China Environment Quality Standards for Surface Water.And the concentrations of the remaining 13 heavy metals were very low or not detected. Most of the heavy metals exhibited distinctive spatial distribution characteristics. The comprehensive pollution status of these heavy metals was generally at an acceptable level with the pollution order of Weinan>Baoji>Xi’an>Xianyang for the local cities. Arsenic was identified as the primary contribution to the health risk for the local population, and should be controlled preferentially.