新疆藁本重金属形态分布及潜在危害研究

目的了解新疆藁本中不同形态的重金属的含量及分布特征,并对重金属的潜在危害进行评估。方法采用经典的BCR法对不同形态的重金属进行提取,原子吸收分光光度法对重金属(Cu、Pb、Cd、As和Hg)进行含量测定。采用单种重金属污染指数及多种重金属综合污染指数对重金属的潜在危害进行了评估。结果新疆藁本中Cu、Pb、Cd、As和Hg的含量分别为43.895 3,0.103 0,1.016 8,0.067 4和0.198 7μg·g~(-1)。其中Cu以残渣态为主,酸溶态及可氧化态的含量相当,可还原态所占的比例最低;Cd以酸溶态所占比例最高,其余各态含量由高到低依次为可氧化态、残渣态和可还原态;Pb以可氧化态含量最高,其余三态的含量相当;As以可氧化态和可还原态为主,酸溶态含量次之,可氧化态含量最低;Hg以酸溶态含量最高,残渣态次之,可还原态的含量最低。所测新疆藁本样品中的Pb、Cd、As和Hg均未检出,Cu为严重污染。结论不同重金属在新疆藁本中的分布各异;单种重金属污染指数及多种重金属综合污染指数可用于评价新疆藁本中重金属元素的潜在危害。

Heavy metal distribition and potential risk assessment in Conioselinum vaginatum

Objective To understand the general rules of the content and distribution of heavy metals in Conioselinum vaginatum , and to evaluate the potential hazard of heavy metals .Methods The samples were prepared by BCR sequential extraction ;Cu ,Pb , Cd ,As and Hg were analyzed by atomic absorption spectrometry (AAS) .Single heavy metal pollution index and comprehensive pollution index were used to assess the potential risk of heavy metals in C .vaginatum .Results The total concentrations of Cu ,Cd , Pb ,As and Hg in C .vaginatum were 43 .895 3 ,0 .103 0 ,1 .016 8 ,0 .067 4 ,and 0 .198 7μg · g -1 ,respectively .Copper in C .vagi‐natum mainly existed in residual state ,the contents of acid solution state and oxidation state were virtually identical ,and the reduc‐tion state was the smallest proportion .Cadimum was mainly associated with acid solution state .The contents of the rest fractions from high to low in sequence were oxidation state ,residual state ,and reduction state .The oxidation state was the main form of lead ,the content of the rest fractions were virtually identical .Arsenic was priority to oxidation and reduction state ,then the acid solution state ,and the content of oxidation state was the lowest .Mercury was bound to acid solution state ,then the residual state , and the content of reduction state was the lowest .Pb ,Cd ,As and Hg were not found in samples ,but Cu was found in high con‐tent .Conclusion The distribution of heavy metals in C .vaginatum was different .Single heavy metal pollution index and compre‐hensive pollution index can be used to evaluate the potential risk of heavy metals in C .vaginatum .