SPECIATE is the Environmental Protection Agency's (EPA) repository of profiles of volatile organic gas and particulate matter air pollution sources. This valuable resource has helped users characterize air emissions by species and source for more than 20 years. The recently updated version, SPECIATE 4.2, contains three categories of air pollutants: particulate matter (dust and ash), volatile organic compounds (benzene, toluene), and other gases (mercury, nitrogen oxides). The current version of this unique database is a collaborative effort involving many EPA air quality scientists, all with the goal of better serving government and industry users who design air-quality and source-receptor modeling applications. Background In the past, environmental professionals were primarily concerned with total particulate matter (PM), volatile organic compounds (VOCs), and other descriptors of air pollution. As air-quality science matured and information became more precise, researchers began to break down PM to size fractions and VOCs to reactive/nonreactive components. SPECIATE breaks down these sub-components even further to the individual compounds that comprise air emissions. Since its beginning in 1988, EPA's SPECIATE database has steadily expanded to include more-specialized data to meet growing user needs. Some key dates in its development include:
The primary purpose of the SPECIATE 4.2 workgroup is to capture new and significant speciation profile data available from the EPA, state agencies, peer-reviewed literature, and other relevant data-gathering sources. The group also updated the technology that allows cross-referencing and conversion of tables, among other user-friendly options, plus database searches by pollutant, keyword, and category. SPECIATE 4.2 at Work The SPECIATE user community has a wide range of needs and interests. Source-receptor modelers use SPECIATE data for emission source chemical profiles. Photochemical modelers use speciation data to characterize the photochemical reactivity of VOC emissions and the chemical composition of PM emissions. Preparers of emission inventories sometimes use SPECIATE data to fill in inventories of toxic air pollutants and greenhouse gases such as methane. Control strategy analysts have an interest in the chemical makeup of VOC and PM emissions to enable control programs to better target appropriate sources. The SPECIATE 4.2 database essentially covers the entire VOC and PM contributing-source sectors in the National Emissions Inventory. These include, for example, EPA data on the speciation of 374 gasoline and diesel liquids and headspace vapors. (The gasoline and diesel on-road sectors are among the largest organic gas emitters.) Some other contributing sources include burning of fossil fuels, agricultural biomass burning, motor vehicle exhaust, and emissions from iron and steel manufacturing facilities and coal-fired power plants. Previous versions of SPECIATE had already integrated profiles on many other sources, such as consumer products, aerosol coatings, pesticides, solvents, and wastewater from data collected by Texas, California and other state studies. Information was also integrated from studies made by other agencies, such as the Department of Energy, and from Canadian databases that provide information on annual releases of pollutants to air, water, land and waste disposal. Databases from many other studies are also included. Still to Come The ever-expanding range of air pollution sources and sub-compounds prompted the SPECIATE workgroup to identify many datasets for which profiles will be added in future versions—for example, biodiesel fuels and advanced technology vehicles. Thus, SPECIATE 4.2, like its predecessor versions, is a work in progress. It welcomes input and suggestions from users, and publishes guidelines to assist profile data collectors with gathering and presenting source profile data for inclusion in the EPA SPECIATE database. SPECIATE 4.2 was developed through a collaboration involving two EPA Office of Research and Development laboratories—the National Risk Management Research Laboratory and the National Exposure Research Laboratory—as well as the EPA's Office of Air Quality Planning and Standards, and Office of Transportation and Air Quality. For more information, visit the SPECIATE Version 4.2 website. You may also contact Jane Ice, NRMRL Office of Public Affairs, 513-569-7311.
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