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Models
The National Exposure Research Laboratory's (NERL) mission is to conduct research on the extent and nature of exposure of humans and the nation's ecosystems to environmental pollutants and other stressors. These are some of the models that show potential exposure of humans and ecosystems.
- Dietary Exposure Potential Model
A downloadable model using extant food databases to estimate exposure to chemical residues. The model was developed for personal computers with the data files designed in dBASEIV® with FoxPro for Windows® applications programs for queries and reporting. Though not intended for risk analysis, the model has proved to be a suitable tool for designing and interpreting exposure measurements, identifying data gaps and establishing priorities for dietary exposure research. Updated April 2003. - Exposure Related Dose Estimating Model (ERDEM) for Assessing Human Exposure and Dose
ERDEM is a PC-based modeling framework that allows for using existing models and for building new physiologically-based pharmacokinetic (PBPK) and pharmacodynamic (PBPK/PD) models. The ERDEM framework provides a modeling tool for characterizing exposures of presumably susceptible subpopulations, e.g. infants and children and calculating estimated internal doses. - Models 3/CMAQ
EPA's third generation air quality modeling system. The primary goals for the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are to improve 1) the environmental management community's ability to evaluate the impact of air quality management practices for multiple pollutants at multiple scales and 2) the scientist's ability to better probe, understand, and simulate chemical and physical interactions in the atmosphere. - EPA Positive Matrix Factorization 1.1 (EPA PMF 1.1) - a receptor models. The user provides a file of concentrations where each column contains a different species and each row contains a different time, typically an hour or a day. Then EPA PMF uses a constrained weighted least squares approach to decompose the file of concentrations into a set of profiles and times series of contributions for each of the profiles. The current versions of EPA PMF (versions 1.x) solve the relatively simple bilinear model.
- Ecosystems Research Environmental Simulation and Modeling
Modeling efforts at ERD primarily focus on simulating the fate and transport of constituents, such as nutrients (nitrogen, phosphorus), sediments (silt, clay, sand), and toxic substances (petroleum products, pesticides, mercury) within watershed areas (saturated and unsaturated soils, groundwater, surface waters, receiving waters). - Center for Exposure Assessment Modeling (CEAM)
CEAM provides proven predictive exposure assessment techniques for aquatic, terrestrial, and multimedia pathways for organic chemicals and metals. CEAM distributes environmental simulation model and data base software for urban and rural nonpoint sources, conventional and toxic pollution of streams, lakes and estuaries, tidal hydrodynamics, geochemical equilibrium, and aquatic food chain bioaccumulation.
EPA Models
- Regulatory Environmental Modeling - The Council for Regulatory Environmental Modeling (CREM), a council of senior managers from across the United States Environmental Protection Agency, was established in 2000 to promote consistency and consensus among environmental model developers and users. CREM has developed a site that includes current models and guidance for environmental models development.