title: Assessment of four commonly employed in vitro arsenic bioaccessibility assays for predicting in vivo relative arsenic bioavailability in contaminated soils.
abstract: Currently, a number of in vitro methods are in use worldwide to assess arsenic (As) bioaccessibility in soils. However, a dearth of research has been undertaken to compare the efficacy of the in vitro methods for estimating in vivo relative As bioavailability. In this study, As bioaccessibility in contaminated soils (n = 12) was assessed using four in vitro assays (SBRC, IVG, PBET, DIN). In vitro results were compared to in vivo relative As bioavailability data (swine assay) to ascertain which methodologies best correlate with in vivo data. Arsenic bioaccessibility in contaminated soils varied depending on the in vitro method employed. For the SBRC and IVG methods, As bioaccessibility generally decreased when gastric-phase values were compared to the intestinal phase. In contrast, extending the PBET and DIN assays from the gastric to the intestinal phase resulted in an increase in As bioaccessibility for some soils tested. Comparison of in vitro and in vivo results demonstrated that the in vitro assay encompassing the SBRC gastric phase provided the best prediction of in vivo relative As bioavailability (R(2) = 0.75, Pearson correlation = 0.87). However, relative As bioavailability could also be predicted using gastric or intestinal phases of IVG, PBET, and DIN assays but with varying degrees of confidence (R(2) = 0.53-0.67, Pearson correlation = 0.73-0.82).
authors.affiliation: Centre for Environmental Risk Assessment and Remediation, Division of Information Technology, Engineering and the Environment, University of South Australia, Mawson Lakes Campus, Mawson Lakes, SA 5095 Australia. Albert.Juhasz@unisa.edu.au
authors.forename: Albert L
authors.initials: AL
authors.lastname: Juhasz
authors.forename: John
authors.initials: J
authors.lastname: Weber
authors.forename: Euan
authors.initials: E
authors.lastname: Smith
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
authors.forename: Matthew
authors.initials: M
authors.lastname: Rees
authors.forename: Allan
authors.initials: A
authors.lastname: Rofe
authors.forename: Tim
authors.initials: T
authors.lastname: Kuchel
authors.forename: Lloyd
authors.initials: L
authors.lastname: Sansom
mesh_terms: D000818:Animals; D001151:Arsenic / Q000032:analysis*; D001681:Biological Assay / Q000379:methods*; D001682:Biological Availability; D004781:Environmental Exposure / Q000032:analysis; D005753:Gastric Mucosa / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000737:chemistry; D012044:Regression Analysis; D012989:Soil Pollutants / Q000032:analysis*; D013270:Stomach / Q000737:chemistry
chemical_list: D012989:Soil Pollutants; D001151:Arsenic