Université de Toulouse, INP-ENSAT, Castanet-Tolosan, France.
J Hazard Mater. 2012 Jun 15;219-220:1-12. doi: 10.1016/j.jhazmat.2012.01.060. Epub 2012 Jan 28.
Biogeochemical behavior of lead (Pb), a persistent hazardous pollutant of environmental concern, strongly depends on its chemical speciation. Therefore, in this review, link between Pb speciation: presence of organic ligands and its environmental behavior has been developed. Both, biogeochemical and ecotoxicological data are discussed in environmental risk assessment context and phytoremediation studies. Three kinds of organic ligands selected for this review include: (1) ethylene diamine tetra-acetic acid (EDTA), (2) low molecular weight organic acids (LMWOAs) and (3) humic substances (HSs). The review highlights the effect of Pb speciation on: (i) Pb fate and behavior in soil; (ii) Pb plant uptake and accumulation in different plant parts; and (iii) Pb-induced phyto-toxicity. Effects of organic ligands on Pb speciation are compared: how they can change Pb speciation modifying accordingly its fate and biogeochemistry in soil-plant system? EDTA forms soluble, stable and phytoavailable Pb-chelates due to high binding Pb affinity. LMWOAs can solubilize Pb in soil by decreasing soil pH or increasing soil organic contents, but have little effect on its translocation. Due to heterogeneous structure, HSs role is complex. In consequence Pb speciation knowledge is needed to discuss phyto-toxicity data and improved soil phytoremediation techniques.
铅（Pb）是一种持久性的有害污染物，其生物地球化学行为强烈依赖于其化学形态。因此，在本综述中，我们研究了 Pb 形态（有机配体的存在）与其环境行为之间的关系。在环境风险评估和植物修复研究的背景下，讨论了生物地球化学和生态毒理学数据。本综述选择了三种有机配体，包括：（1）乙二胺四乙酸（EDTA），（2）低分子量有机酸（LMWOAs）和（3）腐殖质（HSs）。本综述强调了 Pb 形态对以下方面的影响：（i）Pb 在土壤中的命运和行为；（ii）不同植物部位对 Pb 的吸收和积累；（iii）Pb 诱导的植物毒性。比较了有机配体对 Pb 形态的影响：它们如何改变 Pb 形态，从而改变其在土壤-植物系统中的命运和生物地球化学？EDTA 由于与 Pb 的高结合亲和力而形成可溶、稳定且可被植物利用的 Pb-螯合物。LMWOAs 可以通过降低土壤 pH 值或增加土壤有机含量来溶解土壤中的 Pb，但对其迁移影响很小。由于结构不均匀，HSs 的作用比较复杂。因此，需要了解 Pb 形态知识，以讨论植物毒性数据并改进土壤植物修复技术。
