title: Particle size effects on bioaccessible amounts of ingestible soil-borne toxic elements.
abstract: The unified BARGE method was used to examine the effects of soil particle size on the bioaccessible amounts of potentially toxic elements in multi-contaminated soils from a closed landfill site. The results show that bioaccessible As, Al, Cd, Cr, Cu, Mn, Ni, Pb and Zn increased with decreasing soil particle size and the <0.002 mm soil fraction contained much greater amounts of the bioaccessible elements, as compared to other soil fractions (0.002-0.063 mm, 0.063-0.125 mm, and 0.125-0.250 mm). As, Al and Cr had much lower bioaccessibility, as compared to the six cationic heavy metals. In contrast with other elements, As bioaccessibility tended to be higher in the gastrointestinal phase than in the gastric phase. There was a significant soil particle size effect on bioaccessibility of As and Al in the gastrointestinal phase: As bioaccessibility decreased with decreasing particle size, and the finer soil fractions tended to have a higher Al bioaccessibility, as compared to the coarser soil fractions. The research findings prompt the need for further division of soil particle size fractions in order to more accurately assess the bioaccessible amounts of soil-borne potentially toxic elements in contaminated lands.
authors.affiliation: College of Natural Resources and Environment, South China Agricultural University, Guangzhou, China; School of Environment and Life Science, University of Salford, Greater Manchester M5 4WT, United Kingdom.
authors.forename: Junhao
authors.initials: J
authors.lastname: Qin
authors.affiliation: School of Environment and Life Science, University of Salford, Greater Manchester M5 4WT, United Kingdom.
authors.forename: Obinna Elijah
authors.initials: OE
authors.lastname: Nworie
authors.affiliation: School of Environment and Life Science, University of Salford, Greater Manchester M5 4WT, United Kingdom. Electronic address: C.Lin@salford.ac.uk.
authors.forename: Chuxia
authors.initials: C
authors.lastname: Lin
mesh_terms: D004784:Environmental Monitoring / Q000379:methods*; D004787:Environmental Pollution / Q000032:analysis; D019216:Metals, Heavy / Q000737:chemistry*; D010316:Particle Size; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
keywords: Bioaccessibility; Contaminated land; Human health risk; Potentially toxic element; Soil ingestion; Soil particle size