宝鸡市某工业园区灰尘重金属含量、形态及生态风险分析

Content,Forms and Ecological Risk of Heavy Metals in Dust in Changqing Industrial Park of Baoji City

利用X射线荧光光谱法（XRF）和原子荧光分光光度法（AFS）分析了宝鸡市某工业园区灰尘中重金属的含量。结果表明，宝鸡市某工业园区灰尘中As，Co，Cr，Cu，Hg，Mn，Ni，Pb和zn的平均含量分别为23．3，16．4，1591．8，178．2，0．243，346．5，40．2，1586．2和1918．8mg／kg，其中，Cr，Cu，Hg，Pb和Zn累积比较明显；铅锌冶炼厂周边灰尘中As，Cu，Hg，Pb和zn的含量高于电厂。采用修正BCR法（欧洲共同体标准物质局）和原子吸收分光光度法（AAS）研究了灰尘中重金属的形态特征。结果表明，灰尘中Cu主要以残渣态和可氧化态的形式存在，Pb主要以可还原态的形式存在，zn主要以乙酸可提取态的形式存在，Mn和Co主要以乙酸可提取态和残渣态存在，Ni和cr主要以残渣态存在。灰尘中Pb，Zn，Co，Mn和Cu有55％～85％可以发生移动，易被生物利用，危害较大。潜在生态风险评价表明，灰尘中重金属的污染及潜在生态风险达到严重水平，铅锌冶炼厂周边灰尘中重金属的污染和潜在生态风险高于电厂。

The content of heavy metals in the dust in an industrial park of Baoji City was measured by X-Ray fluorescence spectrometry and Atomic fluorescence spectrometry. The results showed that the content of As, Co, Cr, Cu, Hg, Mn, Ni, Pb andZnwas 23.3, 16.4, 1 591.8, 178.2, 0.243, 346.5, 40.2, 1 586.2 and 1 918.8 mg/kg, respectively, of which Cr, Cu, Hg, Pb and Zn accumulated largely and the contents of As, Cu, Hg, Pb and Zn in the dust around lead-zinc smelting plant were higher than that around coal-fired power plant. Analysis on the forms of the heavy metals in the dust by modified BCR （from European Community Bureau of Reference） and AAS（atomic absorption spectrophotometry） indicated that Cu mainly existed oxi- dizable in residual, Pb reducible, Zn extractable in the acetate acid, Mn and Co rich in residual and extract- able in the acetate acid, Ni and Cr mainly the residual. Pb, Zn, Co, Mn and Zn were easy to move and harm- fully utilized by living things. Assessment of potential ecological risk demonstrated that the pollution of heavy metals in the dust and its potential ecological reached to the serious level with that around Ph--Zn smelting plant more severe than coal-fired power plant.