Evaluation of heavy metal mobilization in creek sediment: Influence of RAC values and ambient environmental factors

Guannan Liang; Bo Zhang; Mao Lin; Simiao Wu; Hao Hou; Jia Zhang; Guangren Qian; Xin Huang; Jizhi Zhou

doi:10.1016/j.scitotenv.2017.06.238

Evaluation of heavy metal mobilization in creek sediment: Influence of RAC values and ambient environmental factors

Sci Total Environ. 2017 Dec 31:607-608:1339-1347. doi: 10.1016/j.scitotenv.2017.06.238. Epub 2017 Jul 19.

Authors

Guannan Liang¹, Bo Zhang², Mao Lin¹, Simiao Wu³, Hao Hou³, Jia Zhang³, Guangren Qian³, Xin Huang⁴, Jizhi Zhou⁵

Affiliations

¹ School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
² Center of Solid Waste Management, Shanghai 200235, China.
³ School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
⁴ School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China. Electronic address: huangxin2008@shu.edu.cn.
⁵ School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China. Electronic address: jizhi.zhou@shu.edu.cn.

PMID: 28738527
DOI: 10.1016/j.scitotenv.2017.06.238

Abstract

The risk assessment code (RAC) is a common method for assessing heavy metal (HM) mobility and their potential health risks, based on HM total concentration and chemical speciation. In this study, both the RAC and the influence of ambient environmental factors were investigated in a river sediment system. Sixty-eight sediment samples were collected from the main river system in Shanghai, China. The total concentration and chemical speciation of Cu, Zn, Ni, Pb, Cd, Cr, As, and Hg were determined in the samples. The influence of sediment environmental factors, such as acid-volatile sulfide (AVS), Fe & Mn, and total organic carbon (TOC), on total metal concentrations and speciation was also investigated. The relationship between the main environmental media and distribution of HMs was discussed using PCA and NMDS. The transfer-transformation behaviors of Pb, Ni, and Cr were mainly controlled by AVS and TOC while Zn, Cu, and Cd were influenced by Fe & Mn and TOC. The relationship between the RAC value of HM and environmental factors revealed that 7% of Cr, 23% of Ni, and 15% of Pb had a high risk of mobility at TOC values below 3.5% and sulfite contents below 10mmol/kg. In comparison, 29%, 10%, and 10% of Zn, Cu, and Cd, respectively, had a high risk of mobility at TOC<3.5% and Fe & Mn content >4×10⁵mg/kg. Evidently, the chemical fractions of HM had a strong dependence on the S, Fe, Mn, and organic compounds in the sediment. This study provides a promising pathway for the rapid evaluation of potential risks from HMs in river sediments.

Keywords: Heavy metals; Multivariate analysis techniques; Risk assessment; Sediment.