Science Inventory

Modeling Environment for Total Risk-1A

Description:

MENTOR-1A uses an integrated, mechanistically consistent source-to-dose modeling framework to quantify inhalation exposure and dose for individuals and/or populations due to co-occurring air pollutants. It uses the "One Atmosphere" concept to characterize simultaneous exposures to multiple atmospheric contaminants taking into account their physical and chemical interactions. MENTOR-1A uses, as one of the options, the USEPA’s Stochastic Human Exposure and Dose Simulation (SHEDS) approach.
MENTOR-1A characterizes cumulative exposures to co-occurring air pollutants, and calculates exposure and dose profiles, while providing the ability to focus on mechanism-relevant time scales and subpopulations of interest. This is achieved by combining information, as per the needs of a specific application, on: demographic characteristics of the population under study, outdoor concentration distributions, indoor/outdoor air exchange rates, indoor sources, time-activity diaries, and biologically based dosimetry. It uses the two dimensional Monte-Carlo methodology to quantify variability and uncertainty in model inputs and outputs.
MENTOR-1A can be used for both “Individual Based Exposure Modeling” (IBEM) and “Population Based Exposure Modeling” (PBEM) approaches. Both these approaches employ a “Person Oriented Modeling” (POM) formulation, i.e. they are driven by the attributes and activities of the exposed “real” and/or “virtual” individual(s). While IBEM implementations utilize the information relevant to “actual” individuals (and produce exposure and dose estimates specific to each one of them), the PBEM implementations focus on the statistical characterization of the exposures and doses of selected populations (at the census tract, county, or state etc. level). Thus, the questions posed by any particular environmental health problem can be tailored to small sets of individuals potentially at risk or to larger populations or subpopulations of interest.
MENTOR-1A has been applied to date to simulate (a) regional potential population exposures and (b) urban population exposures and doses to co-occurring gas phase pollutants and particulate matter. Specifically it has been applied to criteria pollutants such as ozone, and PM2.5, and to air toxics such as benzene, formaldehyde and xylene. Additionally, MENTOR-1A has been applied to simulate longer term (year long) exposures to reactive and relatively inert air pollutants, and has also been applied to estimate study-specific exposures and doses to selected air toxics in multiple cities.

Record Details:

Record Type:MODEL
Product Published Date:01/21/2004
Record Last Revised:08/31/2009
Record ID: 75917