University of Torino, Department of Analytical Chemistry, Torino, Italy.
Chemosphere. 2011 Jan;82(2):169-78. doi: 10.1016/j.chemosphere.2010.10.028. Epub 2010 Nov 4.
We evaluated the distribution of 15 metal ions, namely Al, Cd, Cu, Cr, Fe, La, Mn, Ni, Pb, Sc, Ti, V, Y, Zn and Zr, in the soil of a contaminated site in Piedmont (Italy). This area was found to be heavily contaminated with Cu, Cr and Ni. The availability of these metal ions was studied using Tessier's sequential extraction procedure: the fraction of mobile species, which potentially is the most harmful for the environment, was much higher than that normally present in unpolluted soils. This soil was hence used to evaluate the effectiveness of treatment with vermiculite to reduce the availability of the pollutants to two plants, Lactuca sativa and Spinacia oleracea, by pot experiments. The results indicated that the addition of vermiculite significantly reduces the uptake of metal pollutants by plants, confirming the possibility of using this clay in amendment treatments of metal-contaminated soils. The effect of plant growth on metal fractionation in soils was investigated. Finally, the sum of the metal percentages extracted into the first two fractions of Tessier's protocol was found to be suitable in predicting the phytoavailability of most of the pollutants present in the investigated soil.
我们评估了 15 种金属离子（Al、Cd、Cu、Cr、Fe、La、Mn、Ni、Pb、Sc、Ti、V、Y、Zn 和 Zr）在意大利皮埃蒙特污染场地土壤中的分布。该地区被发现严重受到 Cu、Cr 和 Ni 的污染。使用 Tessier 的连续提取程序研究了这些金属离子的有效性：移动物种的分数，对环境最具危害性，远高于无污染土壤中通常存在的分数。因此，该土壤用于通过盆栽实验评估蛭石处理对两种植物（生菜和菠菜）减少污染物可利用性的效果。结果表明，添加蛭石显著降低了植物对金属污染物的吸收，证实了在受金属污染土壤的改良处理中使用这种粘土的可能性。还研究了植物生长对土壤中金属分馏的影响。最后，发现 Tessier 方案前两个部分提取的金属百分比之和适合于预测研究土壤中存在的大多数污染物的植物可利用性。
