Mayer Manfred M, Basta Nicholas T, Scheckel Kirk G
School of Environment and Natural Resources, The Ohio State University, Columbus, OH, United States.
U.S. Environmental Protection Agency, Center for Environmental Solutions and Emergency Response, Land Remediation and Technology Division, Cincinnati, OH, United States.
Front Soil Sci. 2022 Nov 7;2:1-14. doi: 10.3389/fsoil.2022.1028328.
Measuring the reduction of bioaccessible (IVBA) Pb from the addition of phosphate amendments has been researched for more than 20 years. A range of effects have been observed from increases in IVBA Pb to almost 100% reduction. This study determined the mean change in IVBA Pb as a fraction of total Pb (AC) and relative to the IVBA Pb of the control soil (RC) with a random effects meta-analysis. Forty-four studies that investigated the ability of inorganic phosphate amendments to reduce IVBA Pb were identified through 5 databases. These studies were split into 3 groups: primary, secondary, and EPA Method 1340 based on selection criteria, with the primary group being utilized for subgroup analysis and meta-regression. The mean AC was approximately -12% and mean RC was approximately -25% for the primary and secondary groups. For the EPA Method 1340 group, the mean AC was -5% and mean RC was -8%. The results of subgroup analysis identified the phosphorous amendment applied and contamination source as having a significant effect on the AC and RC. Soluble amendments reduce bioaccessible Pb more than insoluble amendments and phosphoric acid is more effective than other phosphate amendments. Urban Pb contamination associated with legacy Pb-paint and tetraethyl Pb from gasoline showed lower reductions than other sources such as shooting ranges and smelting operations. Meta-regression identified high IVBA Pb in the control, low incubated soil pH, and high total Pb with the greater reductions in AC and RC. In order to facilitate comparisons across future remediation research, a set of minimum reported data should be included in published studies and researchers should use standardized bioaccessibility methods developed for P-treated soils. Additionally, a shared data repository should be created for soil remediation research to enhance available soil property information and better identify unique materials.
二十多年来，人们一直在研究通过添加磷酸盐改良剂来降低生物可利用性（IVBA）铅的含量。从IVBA铅含量增加到几乎降低100%，观察到了一系列影响。本研究通过随机效应荟萃分析确定了IVBA铅的平均变化，以总铅（AC）的比例表示，并相对于对照土壤的IVBA铅（RC）。通过5个数据库识别出44项研究，这些研究调查了无机磷酸盐改良剂降低IVBA铅的能力。根据选择标准，这些研究分为3组：主要组、次要组和基于美国环境保护局方法1340的组，主要组用于亚组分析和元回归。主要组和次要组的平均AC约为-12%，平均RC约为-25%。对于美国环境保护局方法1340组，平均AC为-5%，平均RC为-8%。亚组分析结果表明，施用的磷改良剂和污染源对AC和RC有显著影响。可溶性改良剂比不溶性改良剂更能降低生物可利用性铅，磷酸比其他磷酸盐改良剂更有效。与遗留铅漆和汽油中的四乙基铅相关的城市铅污染的降低幅度低于其他来源，如射击场和冶炼作业。元回归表明，对照中IVBA铅含量高、培养土壤pH值低和总铅含量高时，AC和RC的降低幅度更大。为了便于未来修复研究之间的比较，已发表的研究应包括一组最低报告数据，研究人员应使用为磷处理土壤开发的标准化生物可及性方法。此外，应创建一个土壤修复研究共享数据库，以增强可用的土壤特性信息，并更好地识别独特材料。
