East A, Price P, Dawson D, Glen G, Dionisio K, Isaacs K, Hubal EC, Vallero D. The Residential Population Generator (RPGen): Parameterization of residential, demographic, and physiological data to model intraindividual exposure, dose, and risk (presentation). Poster presented at Society of Environmental Toxicology and Chemistry North America 41st Annual Meeting, virtual conference, 2020, DOI: 10.23645/epacomptox.13476864, open access online.
Abstract
Impact/Purpose:
The Residential Population Generator (RPGen) creates synthetic populations with demographic, residential, and physiological characteristics for use in intraindividual probabilistic models of exposure and external and internal doses. RPGen output can be used to support user-developed chemical exposure models that estimate intraindividual exposure in a desired population. By creating profiles and characteristics that determine exposure, RPGen allows modelers to simulate data-driven populations and identify those potentially vulnerable to chemical exposures. This research area will further develop quantitative, objective, flexible and transparent, tools and approaches to assess chemical exposures – esp. improved estimates of exposure and dose for a range of indoor contaminants. The results of these efforts will be of direct benefit to program and regional offices as well as the greater scientific community.
Description:
Chemical exposure is frequently characterized using models bound by time, location, and activity. These models require inputs that describe communities, homes, and individuals. When modeling interindividual variation in exposure, the inputs must meet two requirements: the set of inputs used for an individual must be internally consistent (reflect data that could come from a single individual); and the variation in the data sets across individuals should be representative of intraindividual variation in the modeled population. The Residential Population Generator (RPGen) meets these requirements by creating synthetic populations with demographic, residential, and physiological characteristics for use in intraindividual probabilistic models of exposure and external and internal doses. A database of modeled individuals is created by linking data from US census and US housing surveys based on similar and relevant parameters. Physiological data are generated by linking census data to National Health and Nutrition Examination Survey data with a model of interindividual variation of parameters used in pharmacokinetic modeling. The final modeled population data parameters include characteristics of the individual’s community (region, state, urban or rural), residence (size of property, size of home, number of rooms), demographics (age, ethnicity, income, gender), and physiology (body weight, skin surface area, breathing rate, cardiac output, blood volume, and volumes for body compartments and organs). RPGen output can be used to support user-developed chemical exposure models that estimate intraindividual exposure in a desired population. By creating profiles and characteristics that determine exposure, RPGen allows modelers to simulate data-driven populations and identify those potentially vulnerable to chemical exposures. This document has been reviewed in accordance with US EPA policy and approved for publication.