National Air Toxics Assessment

Previous NATA Assessments

As part of EPA's National Air Toxics Assessment activities, EPA conducted its first national-scale assessment (NATA) for 1996. That assessment included 32 air toxics on the Clean Air Act's list of 187 air toxics plus diesel PM (non-cancer results only). In February of 2006, EPA released the second of its NATA assessments. This assessment was based on emissions from the 1999 National Emission Inventory and included results for 177 air toxics plus diesel PM (non-cancer results only). In June of 2009, EPA released its third NATA, which was based on emissions estimated for 2002. This assessment included results for 181 air toxics plus diesel PM (non-cancer results only). In 2010, EPA released the fourth NATA, based on emissions in the 2005 National Emissions Inventory.  This assessment include results for 179 of the 187 Clean Air Act toxics, including diesel PM (non-cancer results only). The 2011 NATA assessment is the fifth NATA EPA has conducted.

The previous NATA, released in 2011, is the 2005 National-Scale Air Toxics Assessment.

Previous versions of NATA are available in the EPA Archives.