Modeling complex exposures

Abstract

This chapter deals with the aspects of modeling complex exposures, highlighting the integration of various external and internal exposure models, following the exposome paradigm. Several approaches are investigated, relating either to the assessment of the overall chemical mixture as a single compound, or applying the compound-by-compound approach. Identifying the contribution of the various pathways leading to complex exposure requires the precise estimation of the various exposure mechanisms that integrate through the three main exposure routes (inhalation, oral and skin); hence, modeling environmental fate at different scales (such as regional, local or micro-environmental scale) for capturing both far field and near field exposure is essential. Integration of exposure through various pathways and routes occurs at the level of internal dosimetry. This is also reflected in the observed biomonitoring data, highlighting the need for integrated modeling tools that allow the functional link among exposure, internal dose and biomonitoring data. Extrapolation of exposure estimates from individual data to population exposure through advanced probabilistic techniques and agent-based models, as well as the latest advances in personal sensors for tracking activity and location are also presented. The importance of these aspects is highlighted in characteristic case studies regarding indoor air mixtures and multiple pesticide exposure.