title: Effect of aging on bioaccessibility of arsenic and lead in soils.
abstract: The effect of aging on the bioaccessibility of As and Pb in three soils spiked with As (40 or 400 mg kg(-1)), Pb (150 or 1500 mg kg(-1)) or As + Pb (40 mg kg(-1) As and 150 mg kg(-1) Pb) were investigated using the physiologically based extraction test (PBET). Prolonged aging in soils resulted in a decrease in As/Pb bioaccessibility, especially within the first month. After 76 weeks, As/Pb bioaccessibility in soils decreased to a stable level, with 48-84% and 8-34% for bioaccessible As and Pb respectively in the intestinal phase, illustrating that As in spiked soils was much more bioaccessible than Pb. Correlation analysis between sequential extraction data and PBET results showed that the non-specifically sorbed As contributed the most to bioaccessible As, while Pb bound with carbonates and exchangeable fractions were the source for bioaccessible Pb. For future work, minerals containing As and/or Pb instead of their soluble salts can be added to uncontaminated soils to better simulate the natural aging processes.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China; Central and Southern China Municipal Engineering Design & Research Institute, Wuhan, Hubei 430010, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China.
authors.forename: Dong-Xing
authors.initials: DX
authors.lastname: Guan
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China.
authors.forename: Chun-Yang
authors.initials: CY
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China. Electronic address: esluojun@nju.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States. Electronic address: lqma@ufl.edu.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D001151:Arsenic / Q000032:analysis* / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry
chemical_list: D002254:Carbonates; D012987:Soil; D012989:Soil Pollutants; D001151:Arsenic
keywords: Aging; Arsenic; Bioaccessibility; Lead; Sequential extraction