title: Effects of organic matter and ageing on the bioaccessibility of arsenic.
abstract: Arsenic-contaminated soils may pose a risk to human health. Redevelopment of contaminated sites may involve amending soils with organic matter, which potentially increases arsenic bioaccessibility. The effects of ageing on arsenic-contaminated soils mixed with peat moss were evaluated in a simulated ageing period representing two years, during which arsenic bioaccessibility was periodically measured. Significant increases (p = 0.032) in bioaccessibility were observed for 15 of 31 samples tested, particularly in comparison with samples originally containing >30% bioaccessible arsenic in soils naturally rich in organic matter (>25%). Samples where percent arsenic bioaccessibility was unchanged with age were generally poor in organic matter (average 7.7%) and contained both arsenopyrite and pentavalent arsenic forms that remained unaffected by the organic matter amendments. Results suggest that the addition of organic matter may lead to increases in arsenic bioaccessibility, which warrants caution in the evaluation of risks associated with redevelopment of arsenic-contaminated land.
authors.affiliation: Environmental Sciences Group, Royal Military College, PO Box 17 000, Station Forces, Kingston, Ontario K7K7B4, Canada.
authors.forename: Louise
authors.initials: L
authors.lastname: Meunier
authors.forename: Iris
authors.initials: I
authors.lastname: Koch
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Reimer
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D008906:Mining; D010084:Oxidation-Reduction; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D044003:Sphagnopsida / Q000737:chemistry; D014887:Weather
chemical_list: D012987:Soil; D012989:Soil Pollutants; D001151:Arsenic