赫章县土法炼锌致镉污染现状调查

Cadmium pollution caused by artisanal zinc-smelting in Hezhang county

目的了解土法炼锌后镉污染的现状,以及造成的环境污染问题。方法采集镉污染区及对照区的土壤、8种主要农作物和4种动物内脏、饮用水等样品,每类样品分区各采集6份,分析生活环境中镉含量;对污染区54名居民及对照点40名居民进行生活习惯和基本情况问卷调查,并采集一次性尿样测定人群尿镉水平。结果镉污染区内土壤样品含镉量为(15.331 4±8.022 1)μg/g,高于对照区(2.067 5±2.371 6)μg/g(P<0.01);8种主要农作物样品及猪肝、猪肾、鸡肝3种动物内脏样品含镉量均高于对照区的(P<0.05);饮用水含镉量为(0.648 5±0.230 1)μg/L,高于对照区的(0.002 2±0.000 9)μg/L(t=10.282,P<0.01);镉暴露组人群尿镉水平为[9.57(2.55～47.75)]μg/gCr,高于对照组的[2.55(0.68～9.86)]μg/gCr(t=7.418,P<0.01)。结论贵州省赫章县妈姑镇不但土壤镉本底水平高于对照地区,土法炼锌地区更为严重,而且主要农作物、动物内脏、饮用水含镉量及人群尿镉水平均高于对照地区。

Objective To investigate the current situation of cadmium pollution and environmental problems caused by artisanal zinc-smelting. Methods The urine samples of the residents, the samples of soil, eight kinds of common crops, four kinds of animal offal, and domestic water in polluted and control area were collected. The contents of cadmium in all samples were measured. The information on demographics and living behovior were collected with a questionnaire among 54 residents in polluted area and 40 residents in control area. Results The contents of cadmium in soil and domestic water from polluted area were 15. 3314±8.0221 μg/L and 0.6485±0.2301 μg/L, and significantly higher than those from control area（2.0675 ±2.3716 μg/L and 0.0022 ±0.0009 μg/L,P 〈0.01）. The contents of cadmium in eight kinds of common crops and three kinds of animal offal from polluted area were higher than those from control area （P 〈 0.05）. The level of uninary cadmium in exposure group was 9.57 （2.55 - 47.75 ） tμg/g Cr and significantly higher than that in control group （2.55 E 0.68 - 9.86]μg/gCr, P〈0.01）. Conclusion The background level of cadmium in soil in the polluted area is higher than that of control area, and the level of cadmium is aggravated by artisanal zinc-smelting. The contents of cadmium in common crops, animal offal, domestic water and in the urine of the residents in polluted area are higher than those in control area.