Department of Chemistry & Biochemistry, Florida International University, University Park, Miami, FL 33199, USA.
Chemosphere. 2010 Feb;78(8):989-95. doi: 10.1016/j.chemosphere.2009.12.019. Epub 2010 Jan 6.
Laboratory column leaching experiments were conducted to investigate the transport and interaction of As, Cr, and Cu associated with CCA-treated wood in sand with and without peat amendment. Results showed that leaching behavior of As, Cr, and Cu in these substrates were totally different. Substrate characteristics and microorganism activity posed distinct effects on the transport and transformation of these three elements. Arsenic was rapidly leached out from the columns with or without the amendment of peat, while Cr remained in all columns during the entire experimental period (215d). Copper was leached out only in the substrate column without peat. The presence of microorganism clearly facilitated the transport of As, while it did not show obvious effects on the transport of Cr and Cu. Interactions among these three elements were observed during the processes of adsorption and transport. The adsorption of Cu on soil was enhanced with the adsorption of As, likely caused by a more negatively charged soil surface because of As adsorption. The adsorption of Cr on soil increased the adsorption of As due to the additional As binding sites induced by Cr adsorption. These results suggest that As concentrations in the soil affected by CCA-treated wood could largely exceed predictions based on soil adsorption capacity for As. The evaluation of the impact on human health associated with CCA-treated wood should take consideration of the distinct transport characteristics of three elements and their interactions in soils.
开展了实验室柱浸实验，以研究与 CCA 处理木材相关的 As、Cr 和 Cu 在有和没有泥炭添加的砂中的迁移和相互作用。结果表明，这些基质中 As、Cr 和 Cu 的浸出行为完全不同。基质特性和微生物活性对这三种元素的迁移和转化产生了明显的影响。砷在有或没有泥炭添加的柱中迅速浸出，而 Cr 在整个实验期间（215d）都留在所有柱中。铜仅在没有泥炭的基质柱中浸出。微生物的存在明显促进了 As 的迁移，而对 Cr 和 Cu 的迁移没有明显影响。在吸附和迁移过程中观察到了这三种元素之间的相互作用。Cu 在土壤上的吸附因 As 的吸附而增强，这可能是由于 As 吸附导致土壤表面带更多负电荷。Cr 在土壤上的吸附增加了 As 的吸附，因为 Cr 吸附诱导了更多的 As 结合位点。这些结果表明，受 CCA 处理木材影响的土壤中的 As 浓度可能大大超过基于土壤对 As 的吸附容量的预测。评估与 CCA 处理木材相关的对人类健康的影响时，应考虑到土壤中三种元素的独特迁移特征及其相互作用。
