TRJ Environmental


Consolidated Human Activity Database

The Consolidated Human Activity Database (CHAD) contains data obtained from pre-existing human activity studies that were collected at city, state, and national levels. CHAD is intended to be an input file for exposure/intake dose modeling and/or statistical analysis. CHAD is a master database providing access to other human activity databases using a consistent format. This facilitates access and retrieval of activity/and questionnaire information from those databases that EPA currently has access to-and-uses-in its various regulatory analyses undertaken by program offices.

EPA Air Quality System

The Air Quality System (AQS) is EPA's repository of ambient air quality data. AQS stores data from over 10,000 monitors, 5000 of which are currently active.

EPA Human Exposure Modeling (APEX/TRIM.Expo)

The Air Pollutants Exposure Model (APEX) is a PC-based model that was derived from the probabilistic NAAQS Exposure Model for carbon monoxide (pNEM/CO). A draft report describing pNEM/CO is available. Reports describing prior OAQPS applications of the pNEM to ozone also are available. APEX serves as the human inhalation exposure model within the Total Risk Integrated Methodology (TRIM) model framework. See TRIM - General Information page for historical information about TRIM and peer review of the TRIM and TRIM.Expo approach. APEX is intended to be applied at the local, urban, or consolidated metropolitan area scale and currently only addresses inhalation exposures. The model simulates the movement of individuals through time and space and their exposure to the given pollutant in various microenvironments (e.g., outdoors, indoors residence, in-vehicle). The user may choose the number and types of microenvironments to be included, select the time period of interest, use either monitored ambient air quality data or values provided from dispersion or other modeling runs, and use either a mass balance approach or an empirical ratio-based (factor) approach to estimate indoor and/or in-vehicle concentrations. Results of the APEX simulations are provided as hourly and summary exposure and/or dose estimates, depending on the application, for each individual included in the simulation as well as summary statistics for the population modeled.

Geographical Mobility/Migration Data

This site provides four (unrelated) sources of mobility and migration data.

International Society of Exposure Analysis

The International Society of Exposure Analysis was established in 1989 to foster and advance the science of exposure analysis related to environmental contaminants, both for human populations and ecosystems. The membership promotes communication among all disciplines involved in exposure analysis, recommends exposure analysis approaches to address substantive or methodological concerns, and works to strengthen the impact of exposure assessment on environmental policy.

Journal of Exposure Science and Environmental Epidemiology

The Journal of Exposure Science and Environmental Epidemiology (JESEE) is a peer-reviewed publication that publishes research important to exposure assessment for toxic substances, environmental epidemiology that includes a strong exposure analysis component and related disciplines that advance the exposure assessment process. JESEE also publishes papers on exposure analysis such as measurements and modeling; mechanisms of exposure; development of molecular biomarkers; genomic, proteomic, and metabonomics studies that assess exposure in the context of health effects; studies on chemical, biological, and physical principles required to analyze human exposure from single and multiple routes; occupational exposure studies; and, population-based studies. JESEE is the official publication of the International Society of Exposure Analysis (ISEA).

Life Tables

These tables (prepared by the National Center for Health Statistics) provide life expectancy data.

National Ambient Air Quality Standards

The Clean Air Act, which was last amended in 1990, requires EPA to set National Ambient Air Quality Standards (NAAQS) for wide-spread pollutants from numerous and diverse sources considered harmful to public health and the environment. The Clean Air Act established two types of national air quality standards. Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against visibility impairment, damage to animals, crops, vegetation, and buildings. The Clean Air Act requires periodic review of the science upon which the standards are based and the standards themselves.

EPA has set NAAQS for six principal pollutants, which are called "criteria" pollutants. They are listed below. For a summary table of the current NAAQS, click on the following link: NAAQS Table.

For further information about the current or prior review of any of the NAAQS or information related to the implementation of control programs designed to attain the standards, please go the links listed below:

Information on EPA's revised process for reviewing the NAAQS

Ozone (O3) Air Quality Standards Implementation
Particulate Matter (PM) Air Quality Standards PM10 Implementation
PM2.5 Implementation
Carbon Monoxide (CO) Air Quality Standards Implementation
Sulfur Dioxide (SO2) Air Quality Standards Implementation
Nitrogen Oxides (NOx) Air Quality Standards Implementation
Lead (Pb) Air Quality Standards Implementation

NOAA National Weather Service - Air Quality Forecasts

This website provides a map showing NOAA's National Weather Service Air Quality Forecast Guidance. Ozone is shown as 1-hour and 8-hour concentrations (in parts per billion or ppb), updated twice daily. Official Air Quality point forecasts, issued by state and local air quality forecasters, along with additional information on air quality can be found under EPA's AIRNow site. Surface and column-average concentrations of predicted smoke for large fires are displayed as 1-hour averages (in micrograms per cubic meter), updated each day. Fire locations are provided by NOAA / NESDIS' Hazard Mapping System. For further information, see the Air Resources Laboratory web site.

Population Projections

The Population Projections Program creates projections of the resident population for the United States and for each of the 50 states and the District of Columbia.