样品处理与保存方法对表层沉积物中金属形态分析的影响

Effects of Treatment and Storage Methods on Partitioning Pattern Analysis of Metals in Surficial Sediments

利用改进的Tessier连续萃取法研究了冷藏、冷冻、冻干、烘干和风干等样品处理与保存方法对表层沉积物中金属形态的影响。结果表明:各样品处理与保存过程对沉积物中Fe、Mn、Cu、Zn及Pb的形态均具有不同程度的影响,其中Fe的形态受其影响最小(<3.3%),Mn的形态受其影响最大(最高可达10.2%);冻干对各金属形态的影响最小(<4.6%);烘干和风干对重金属Cu、Zn和Pb的可交换态(Ⅰ+Ⅱ)和非残渣态(Ⅰ-Ⅴ)分布影响较大,而冷藏、冷冻和冻干的影响相对较小。因此,综合考虑重金属的形态分布及其生物可利用性,冻干是较理想的沉积物样品处理与保存方法。

Effects of treatment and storage methods, including refrigerating, freezing, freezedrying, oven drying and air-drying on the partitioning patterns of metals in surficial sediments, were investigated through the modified sequential extraction procedure. The results showed that there were different affections for the partitioning patterns of Fe, Mn, Cu, Zn and Pb by the five methods, and the effect of the five methods on partitioning pattern of Fe （〈3.3%） was found lowest among the metals of Fe, Mn, Cu, Zn and Pb, and Mn the highest （up to 10.2%） ;The lowest effect of the methods on partitioning patterns of all the metals was the freeze-drying （〈4.6 %）. It was also observed that the effects of oven drying and air-drying on distribution of Cu, Zn and Pb in exchangeable fractions （ Ⅰ ＋ Ⅱ ） or non-residual fractions （ Ⅰ -Ⅴ ） were higher compared to the other three treatment methods. Thus, it was concluded that the method of freeze-drying was the most suitable treatment and storage method while investigating the partitioning pattern and bioavailability of metals in surficial sediments.