Lead bioaccessibility in 12 contaminated soils from China: Correlation to lead relative bioavailability and lead in different fractions

JOURNAL OF HAZARDOUS MATERIALS

卷:295

Article

Li, Jie¹  Li, Kan¹  Cave, Mark²  Li, Hong-Bo¹  Ma, Lena Q.^1,3 

[1] Nanjing Univ, Sch Environm, State Key Lab Pollut Control & Resource Reuse, Nanjing 210046, Jiangsu, Peoples R China

[2] British Geol Survey, Keyworth NG12 5GG, Notts, England

[3] Univ Florida, Soil & Water Sci Dept, Gainesville, FL 32611 USA

关键词: Lead;    Contaminated soil;    Bioaccessibility;    Bioavailability;    Sequential extraction;   

DOI  :  10.1016/j.jhazmat.2015.03.061

来源: Elsevier

【 摘 要 】

This study investigated the relationship between Pb relative bioavailability (RBA) and bioaccessibility, and their relationships with Pb in different pools in soils. Twelve Pb-contaminated soils representing different contamination sources from China were analyzed for Pb bioaccessibility using four in vitro methods (UBM, SBRC, IVG, and PBET), Pb-RBA using a mouse blood model, and Pb fractionation using sequential extraction. Lead bioaccessibility in the gastric phase (GP) and Pb-RBA was generally lower in mining soils (0.46-29% and 7.0-26%) than smelting (19-92% and 31-84%) and farming soils (13-99% and 51-61%), with more Pb in the residual fraction in mining soils. Lead bioaccessibility varied with assays, with SBRC (3.0-99%) producing significantly higher bioaccessible Pb than other assays (0.46-84%) in the gastric phase. However, Pb bioaccessibility in the intestinal phase (IP) of all assays sharply decreased to 0.01-20% possibly due to Pb sorption to solid phase at higher pH. Lead bioaccessibility by UBM-GP assay was best correlated with Pb-RBA (r(2)=0.67), followed by IVG-GP (r(2)=0.55). Among different Pb fractions, strong correlation was found between Pb bioaccessibility/Pb-RBA and the sum of exchangeable and carbonate fractions. Our study suggested that UBM-GP assay has potential to determine Pb bioaccessibility in contaminated soils in China. Published by Elsevier B.V.

【 授权许可】

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