Characterizing exposures to arsenic and co-occurring contaminants using the Modeling Environment for TOtal Risk studies (MENTOR)
P.G. Georgopoulos, S.W. Wang, A.F. Sasso, S.S. Isukapalli
Environmental & Occupational Health Sciences Institute, Piscataway, NJ
Studies employing the probabilistic source-to-dose modeling framework of the Modeling System for TOtal Risk studies (MENTOR) for Multiple co-occurring contaminants and Multimedia, Multipathway, Multiroute exposures (4M) are presented and their outcomes are discussed in the context of relative source contribution. MENTOR-4M combines microenvironmental and human activities characterization to assess the relative contribution of (1) media (e.g., water, food, dust), (2) pathways (e.g., drinking water, diet, hand-to-mouth) and (3) routes (e.g., oral, inhalation, dermal) to (4) the exposures of individuals or populations to multiple contaminants. This framework addresses aggregate and cumulative exposures to co-occurring pollutants in a mechanistically consistent manner, and provides the ability to focus on toxicologically relevant time scales and subpopulations of interest. Specifically, MENTOR-4M calculates target tissue doses (and corresponding biomarker levels of contaminants and their metabolites) by employing a generalized PBTK model for mixtures, the components of which can have widely varying absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. This attribute of the MENTOR framework offers the advantage of allowing model evaluation against field data that include biomarker measurements across populations of interest.
This work is funded in part by the USEPA through Cooperative Agreement CR-83162501 and STAR Grant GAD R 832721-010. Viewpoints expressed here are the responsibility of the authors and do not necessarily reflect views of the USEPA or its contractors.