铅锌银矿区蔬菜中重金属吸收特征及分布规律

Uptake of heavy metal in vegetables grown in Pb-Zn-Ag mine, Nanjing

主要通过高压密闭消解方法,利用等离子质谱(ICP-MS)对采自南京市栖霞山铅锌银矿区周围几大类常见的蔬菜中Pb、Cd、Cr、As等重金属元素含量进行分析研究。结果表明,不同蔬菜品种对重金属的富集程度有较大区别,整体上有葱蒜类>绿叶类>食用菌类>白菜类>薯芋类>直根类>茄果类>豆类的趋势,Pb在叶菜类(葱蒜类和绿叶类)中具有相对强的富集程度。同一蔬菜不同部位对金属的吸收特征也不同,萝卜(Raphanus sativus)叶中Pb(含量范围为42.120～1.461μg·g-1)和As平均含量为根(Pb含量范围为3.571～0.279μg·g-1)的10倍,黄豆(Giycinemax(L)Merrill)中重金属质量分数依次是豆叶+豆角皮〉豆茎〉黄豆皮〉黄豆。此外矿区菜园地中蔬菜对金属的富集和迁移受矿山开采的影响。通过本结果,可进一步了解矿区农田蔬菜受重金属污染的程度和特征,为合理布局蔬菜的种植提供建议,为进一步研究蔬菜中重金属的作用情况提供参考。

Analytical results of heavy metals in vegetables contaminated with a Lead-Zinc-Silver（Pb-Zn-Ag）mine in Qixia District in Nanjing are presented here. Total concentrations of Lead （Pb）, Chromium （Cr）, Copper （Cu）, Zinc （Zn）, Arsenic （As） and some other elements in vegetables were determined by inductively coupled plasma-mass spectrometry（ICP-MS）. Among all these kinds of vegetables determined, shallot, garlic and leave-vegetables show the highest content of heavy metals, especially Pb, and bean vegetables the lowest. Besides, there is some tendency of distribution for heavy metals in different parts of one kind of vegetable, for example, the content of Pb, as well as As, in root is ten times as high as that in leaves of raphanus sativus. What’s more, some reasonable suggestions on how to effectively configure the planting area of vegetables are also given.