title: Bioaccessibility of arsenic and cadmium assessed for in vitro bioaccessibility in spiked soils and their interaction during the Unified BARGE Method (UBM) extraction.
abstract: Recent decades have seen a growing popularity of in vitro bioaccessibility being utilised as a screening tool in human health risk assessment. However the existing bioaccessibility studies only focus on single contaminant. Considering human are likely to ingest multi-contaminants, these contaminants could interact within human gastrointestinal tract which may lead to an increase or decrease in bioaccessibility. In this study, seven different types of soil were spiked with arsenic (As) or cadmium (Cd) and aged for one year. The effects of soil properties on the bioaccessibility were examined. Moreover, the interaction between As and Cd in simulated human digestive system was studied by mixing As-spiked soil with Cd-spiked soil of the same type during bioaccessibility test. Results shows the bioaccessibility of As ranged from 40 ± 2.8 to 95 ± 1.3% in the gastric phase and 16 ± 2.0 to 96 ± 0.8% in the intestinal phase whilst a significant difference was observed between Cd gastric bioaccessibility (72 ± 4.3 to 99 ± 0.8%) and intestinal bioaccessibility (6.2 ± 0.3 to 45 ± 2.7%). Organic carbon, iron oxide and aluminium oxide were key parameters influencing the bioaccessibility of As (gastric and intestinal phases) and Cd (intestinal phase). No interactions between As and Cd during bioaccessibility test were observed in any soils, which indicates As and Cd may age independently and did not interact while being solubilised during bioaccessibility test. Thus additive effect may be proposed when estimating the bioaccessibility of mixtures of independently-aged As and Cd in soils.
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Brisbane, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia.
authors.forename: Qing
authors.initials: Q
authors.lastname: Xia
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Brisbane, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia.
authors.forename: Cheng
authors.initials: C
authors.lastname: Peng
authors.affiliation: Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia; Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Dane
authors.initials: D
authors.lastname: Lamb
authors.affiliation: Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia; Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Megharaj
authors.initials: M
authors.lastname: Mallavarapu
authors.affiliation: Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia; Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
authors.affiliation: The University of Queensland, National Research Centre for Environmental Toxicology, Brisbane, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Callaghan, NSW 2308, Australia. Electronic address: j.ng@uq.edu.au.
authors.forename: Jack C
authors.initials: JC
authors.lastname: Ng
mesh_terms: D000537:Aluminum Oxide / Q000032:analysis; D001151:Arsenic / Q000378:metabolism*; D001682:Biological Availability; D002104:Cadmium / Q000378:metabolism*; D002244:Carbon / Q000032:analysis; D005290:Ferric Compounds / Q000032:analysis; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D005290:Ferric Compounds; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; C000499:ferric oxide; D002244:Carbon; D000537:Aluminum Oxide; D001151:Arsenic
keywords: Bioaccessibility; Contaminated soil; In vitro assessment; Mixed contamination; Risk assessment; Soil properties