为了解广东省丰顺县尖笔岽铅锌矿周边土壤中重金属含量及其潜在生态风险，采用野外采样及实验室测定分析的方法，以矿山周边4个片区表层土壤（0~20 cm）为研究对象，测定了土壤中Pb、Zn、Cu、Cd、Cr和As含量，分别采用单因子评价、综合指数法评价、Hakanson潜在生态风险评价和健康风险评价以评价土壤的重金属水平和潜在生态风险，结果表明：在目前尚未开采的状况下，该矿区周边土壤已存在一定的重金属污染，4个研究片区大部分土壤样品 Pb（平均值为106.77 mg·kg-1）、Cd（平均值为0.27 mg·kg-1）、Zn（平均值为55.75 mg·kg-1）质量分数均超过广东省背景值；污染指数显示主要以Pb（极大值4.57）、Cd（极大值2.98）、Zn（极大值1.41）污染为主；综合指数法评价表明老虎隔水稻田片区土壤达到重度污染水平，综合污染指数达到3.47，同时片区土壤达到中度污染水平的土壤样品数目占总样品数的51.02%；而Hakanson潜在生态风险评价表明该矿区潜在生态风险处于低程度，4个片区潜在生态风险指数（RI）均未超过150，平均值为110.67，这与该矿尚未开采，暂受到人类活动影响较小有关，土壤中6种重金属的潜在生态危害性顺序大体为Cd>Pb>As>Cu>Zn>Cr，其中Cd（贡献率达73.65%~79.67%）、Pb（贡献率达10.24%~18.83%）是主要的生态风险贡献因子；健康风险评价也表明该矿区重金属非致癌、致癌风险处于可接受范围内，4个研究片区非致癌风险值及总重金属非致癌风险值之和均小于1，6种重金属3种暴露途径均体现出口腔摄入>皮肤摄入>呼吸摄入，非致癌风险值大小顺序为Pb>As>Cu>Zn>Cd>Cr。综上所述，该拟开采矿区周边土壤受到一定的重金属污染，潜在生态风险处于低程度，健康风险处于可接受范围内，这与开采多年的铅锌矿周边土壤重金属污染情况大不相同，该拟开采铅锌矿在其后续的开采、选矿活动中，应高度重视重金属污染的研究和防治，采取合理措施，防止加剧周边土壤的重金属累积。%In order to comprehand the content and potential ecological risk of haavy metals in the surrounding soil of Jianbidong lead-zinc mining in Fengshun Guangdong, adopting the methods of field sampling and laboratory analysis test, regarding four different surface soil areas as analyzing case studies, the heavy metal contents (Pb、Zn、Cu、Cd、Cr、As) of the surrounding surface soil from the lead-zinc mining were determined.The analyzing methodologies include single factor evaluation, Nemerow comprehensive index method, evaluation of Hakanson potential ecological risk assessment and health risk assessment so that to assess the level and potential ecological risk of heavy metals from the soil. The result shows that: under the undeveloped situation of this lead-zinc mining, the soil around the mining area has occourred somewhat pollution of heavy metals, and most of the soil samples with Pb(average of 106.77 mg·kg-1), Cd(average of 0.27 mg·kg-1), Zn(average 55.75 mg·kg-1) from the four research areas were over the background value of Guangdong Province;The polluted index shows Pb(maximum value of 4.57), Cd(maximum value of 2.98), Zn(maximum value of 1.41) pollutions are the most common;Comprehensive index shows polluted degree of the soil of Laohuge paddy field area is the most serious and the value is accounting 3.47. Meanwhile, the number of the soil samples which have medium degree of pollution is equal 51.02% of the number of the whole;While the Hakanson potential ecological risk assessment indicated that the mining potential ecological risk at low level, the four area of potential ecological risk index (RI) was less than 150, the average value was 110.67, probably due to the fact that the mine area were still undeveloped, and influence of human activities is relatively weak,the potential ecological harm order of six kinds of heavy metals in the soil roughly was Cd>Pb>As>Cu>Zn>Cr, Cd (the contribution rate of 73.65%~79.67%) and Pb (the contribution rate of 10.24%~18.83%) were the main contribution of ecological risk factors; Health risk assessment of heavy metals also show that the non cancer, cancer risk is acceptable, four research area of non carcinogenic risk value and total heavy metal non carcinogenic risk and value are all less than 1, six kinds of heavy metals in three routes of exposure are embodied in the oral intake of > the skin intake of > the breath intake of, non carcinogenic risk value the size of the order of Pb>As>Cu>Zn>Cd>Cr.In summary, the fitting soil around the mining areas is sufferred from heavymetals pollution. The potential ecological risk is at a low level. The health risk is within the acceptable range, which is not similar to other recent lead-zinc mining area. In the following function of that area, research and prevention of heavy metal pollution should be paid more attention, and reasonable measures should be taken in order to prevent the intensification of the surrounding soil accumulation of heavy metals.
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