title: New Insights into the Reliability of Automatic Dynamic Methods for Oral Bioaccessibility Testing: A Case Study for BGS102 soil.
abstract: Dynamic flow-through extraction is attracting a great deal of attention for real-time monitoring of the bioaccessible fraction of metal species in environmental solid substrates compared to its batchwise manual counterparts. There is however a lack of studies on the harmonization and validation of in vitro dynamic methods for physiologically based extraction tests against in vivo bioavailability methods. This work is aimed at evaluating the reliability of dynamic flow-through extraction methods for estimation of oral bioaccessible fractions of Cu, Zn, Pb, Ni, Cr, and As under worst-case extraction conditions in the gastric compartment based on the BGS102 guidance soil using the in vivo validated Unified BARGE (UBM) test, commonly performed under batchwise mode. Good overall agreement between batch and dynamic UBM results was obtained for the tested elements, except for Pb, as a consequence of the slow leaching kinetics identified with the dynamic method and the contribution of readsorption phenomena in the course of the gastric digestion. Metal-soil phase associations and their relationship with gastric bioaccessible fractions were elucidated using the so-called Chemometric Identification of Substrates and Element Distributions method based on sequential extraction with a variety of chemicals of increasing acidity as applied to both static and dynamic bioaccessibility data.
authors.affiliation: British Geological Survey, Keyworth, Nottingham NG12 5GG, United Kingdom.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Cave
authors.affiliation: FI-TRACE group, Department of Chemistry, University of the Balearic Islands , Carretera de Valldemossa km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Rosende
authors.affiliation: British Geological Survey, Keyworth, Nottingham NG12 5GG, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Mounteney
authors.affiliation: British Geological Survey, Keyworth, Nottingham NG12 5GG, United Kingdom.
authors.forename: Amanda
authors.initials: A
authors.lastname: Gardner
authors.affiliation: FI-TRACE group, Department of Chemistry, University of the Balearic Islands , Carretera de Valldemossa km 7.5, 07122 Palma de Mallorca, Illes Balears, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Miró
mesh_terms: D004781:Environmental Exposure; D004784:Environmental Monitoring; D015203:Reproducibility of Results; D012987:Soil; D012989:Soil Pollutants
chemical_list: D012987:Soil; D012989:Soil Pollutants