Cadmium, lead and arsenic contamination in an abandoned nonferrous metal smelting site in southern China: Chemical speciation and mobility

Jiejie Yang; Ziwen Guo; Luhua Jiang; Emmanuel Konadu Sarkodie; Kewei Li; Jiaxin Shi; Yan Deng; Zicheng Zhang; Hongwei Liu; Yili Liang; Huaqun Yin; Xueduan Liu

doi:10.1016/j.ecoenv.2022.113617

Cadmium, lead and arsenic contamination in an abandoned nonferrous metal smelting site in southern China: Chemical speciation and mobility

Ecotoxicol Environ Saf. 2022 Jul 1:239:113617. doi: 10.1016/j.ecoenv.2022.113617. Epub 2022 May 14.

Authors

Affiliations

¹ School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
² School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China. Electronic address: jiangluhua@csu.edu.cn.
³ China Construction Group The Fifth Construction Co., Ltd., Beijing 100024, China.

PMID: 35580509
DOI: 10.1016/j.ecoenv.2022.113617

Abstract

The investigation of chemical speciation of primary toxic metal(loid)s (Cd, Pb, and As) in soil profile in nonferrous metal smelting site is a key to the assessment of their mobility characteristics and formulation of subsequent remediation strategy. In this study, 74 soil samples were collected at 12 different soil profiles; soil physio-chemical properties and total content of Cd, Pb and As and corresponding chemical speciation were also determined. The results showed that the mean total concentration followed the order of Pb > As > Cd. A large proportion of Pb, Cd and As were accumulated in upper soil profiles (depth < 3 m). Heavy pollution of Pb, Cd and As were observed in the whole soil profile at the area of fuel oil storage tank (ZY6) and lead smelting area (ZY8). The dominant fraction of Cd was exchangeable fraction (F1); Pb was dominant in Fe/Mn oxides-bound fraction (F3) in most cases; Crystallized Fe/Al hydrous oxides bound fraction (F4) generally accounted for a large proportion of As. Mobility factor (MF) followed the order Cd > As > Pb, indicating that Cd was the most mobile element in soil profiles. Pearson correlation analysis found that MF_Cd was significantly positively correlated to soil silt; the F4 fraction percentage of As was significantly positively correlated to soil redox potential (Eh). Additionally, MF_Cd/Pb was found to be positively correlated to crystalline iron (Fe_c), while negatively correlated to amorphous iron (Fe_o). The findings reported in this study, on the basis of distribution characteristics of chemical speciation could provide a new solution for future soil remediation at the site. Long-term solutions to metal(loid)s pollution might be offered by microbial-assisted soil washing technique that promotes the transformation of Fe/Mn oxides-bound fraction and organic/sulfide-bound fraction.

Keywords: Mobility in soil; Remediation strategies; Smelting site; Toxic metal(loid)s fractionation; Vertical distribution.

MeSH terms

Arsenic* / analysis
Cadmium / analysis
China
Environmental Monitoring / methods
Iron / analysis
Lead / analysis
Metals, Heavy* / analysis
Oxides / analysis
Soil / chemistry
Soil Pollutants* / analysis

Substances

Metals, Heavy
Oxides
Soil
Soil Pollutants
Cadmium
Lead
Iron
Arsenic