Combining in vitro oral bioaccessibility methods with biological assays for human exposome studies of contaminants of emerging concern in solid samples

In vitro physiologically-based extraction tests (PBETs) play a key role in human risk assessment/exposure of xenobiotics from environmental and food samples. These methods are aimed at determining potential bioaccessible species in the human gastrointestinal tract and, thus, might serve as the first step for correct estimation of average daily intakes in oral exposition studies. However, the use of PBETs should be restricted to those methods that correlate well with bioavailability tests using animal models or ecotoxicity data to assure that they are mimicking physiological conditions appropriately. In this review, in vitro PBETs for assessing bioaccessibility of contaminants of emerging concern are first presented including steps for reliable processing of the gastrointestinal extracts. Particular attention is given to those PBETs that are combined or validated against bioassays including in vitro cytotoxicity studies, adhesion/absorption studies using cell lines, transepithelial cell transport, and in vivo analysis based on animal models. This review serves as a tutorial guide to aid practitioners in selecting the most suitable bioaccessibility tests for human exposomics of contaminants of emerging concern in solid substrates. (C) 2020 Elsevier B.V. All rights reserved.