Linking probabilistic exposure models for non-food and food sources to calculate aggregate consumer exposure: Case study on Bisphenol A

摘要

Background There is a rising demand for more holistic risk assessments to better ensure consumers' safety. In the estimation of chemical risks, the quantification of the overall exposure is a crucial step. For this purpose, an exposure assessment needs to account for multiple routes and multiple chemicals that have the same effect. Realistic exposure estimates can be obtained by using probabilistic models, which account for variability in human behavior. Objectives Within the EuroMix EU project, different food and non-food exposure models are linked to facilitate the exposure assessment from different sources for different chemicals. In this work, we in particular link the results of the probabilistic models MCRA and PACEM to assess aggregate exposure from food and consumer products. As a test case, the exposure to the endocrine disrupting substance Bisphenol A (BPA) is assessed. BPA is present in both food and non-food sources, the latter being polycarbonate plastics, epoxy resins and thermal paper. Since the metabolization of BPA differs depending on the intake routes, aggregation can only be performed on the level of internal exposure. Methods MCRA is a web-based program for Monte Carlo risk assessment with emphasis on exposure from food sources. PACEM is a probabilistic aggregate consumer exposure model, which was first used for exposure assessments for ingredients in cosmetics and personal care products. For the case study on BPA, PACEM is adapted to account for all non-food sources containing BPA and all age groups, including toddlers and children. The internal exposure to BPA is calculated by feeding the external aggregate exposure from each exposure source into a PBPK model. Human biomonitoring studies are used for validation. Results The case study on BPA results in individual-based probabilistic aggregate consumer exposure estimates. All relevant routes and sources are considered, and internal exposure is calculated for all routes. To our best knowledge, this is the first probabilistic assessment of internal aggregate exposure of BPA across all possible pathways. These results are important because they will help to evaluate every-day exposure to and risk from BPA in an integrated and realistic way.