黔西北土法炼锌矿区重金属污染现状及其环境影响评价

The Polluted Situation of Heavy Metals in Pb-Zn Mining Area of Northwest of Guizhou Province and the Evaluation of Environmental Impaction

在对黔西北土法炼锌四个矿区周围的土壤和植物（蔬菜和作物等）进行全面调查的基础上，时土壤和植物重金属（Zn、Cd、Pb、Cu和As）污染现状进行了监测与初步评价。结果表明，四个土法炼锌矿区除野马川的土壤属于中度污染外，其余全部处于严重污染状态，并且Cd是每个矿区的主要污染元素；土法炼锌矿区周围的蔬菜已全部受到严重污染，综合污染指数在10.83～40．67之间，属于重度污染，蔬菜污染主要以Cd为主，超过国家食品卫生标准54倍；矿区周围其他植物如土豆、玉米和绿肥等中的重金属亦严重超标，主要以Pb污染为主，超过国家食品卫生标准366．75倍。说明矿区土壤中种植作物的生长及食用安全已经受到重金属污染的严重影响，对居民健康构成潜在威胁。

The pollution situation of heavy metal of soil and plant were determined and evaluated, based on overall investigation of Pb - Zn mining area＇ s soil and plant （vegetable and crop etc. ） in northwest of Guizhou. The result is showed as follows ： besides soil of YEMACHUAN which belongs to middle degree pollution, the others of four Pb- Zn mining area all belong to grave pollution, and Cd is the main polluted element of every mining area ; Vegetable in mining area have already been polluted gravely, pollution index is between 10.83- 40.67, Cd is the main polluted element of vegetable, exceeding the national food hygiene standards to 54 times; The heavy metal in potato, maize and other plant also go beyond standard around mining area, Pb is the main polluted element of other plant, exceeding national food hygiene standards to 366.75 times. The heavy metals not only directly affect the growth of crops and the edible safety but also potentially influence the health of the neighboufing people.