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FACT SHEET: Second Integrated Urban Air Toxics Report to Congress


  • On August 21, 2014, the U.S. Environmental Protection Agency (EPA) released the Second Integrated Urban Air Toxics Report to Congress - the final of two reports required under the Clean Air Act (CAA) to inform Congress of EPA’s actions and progress in reducing public health risks from urban air toxics.
  • Using national emissions and air quality data, the report shows the substantial progress that has been made to reduce air toxics across the country since the passage of the Integrated Urban Air Toxics Strategy in 1999.
  • The 2005 National Air Toxics Assessment (NATA), which is the latest complete analysis of air toxics, has been available since 2011 and provides EPA, state, local and tribal agencies with a prioritization tool to work toward improving air quality in areas of increased risk.
  • The report confirms that while some areas of the country experienced elevated levels of risk (based on the 2005 NATA), the country has made substantial progress, reducing millions of tons of toxic pollutants over the last two decades.
  • Since 2005, emissions of air toxics have declined further as a result of recent EPA regulations and enforcement actions, as well as the implementation of state and local programs to address air toxics from both mobile and stationary sources.
  • The report highlights some of the results achieved through EPA’s air toxics regulations, including:
    • A 66 percent reduction in benzene;
    • A nearly 60 percent reduction in mercury from man-made sources like coal-fired power plants;
    • An 84 percent decrease of lead in outdoor air;
    • From 1990 through 2012, the removal of an estimated 1.5 million tons per year of hazardous air pollutants (HAPs) from stationary sources, and approximately 3 million tons per year of criteria pollutants as a co-benefit of HAP reductions;
    • The removal of an estimated 1.5 million tons per year of HAPs from mobile sources, which represents a 50 percent reduction in mobile source HAP emissions.
  • Even with this progress, additional work remains to improve our understanding of air toxics and to effectively reduce remaining risks, particularly in overburdened communities.
  • The Report identifies six challenges to the current air toxics program where continued effort is needed:
    • Improved emissions data
    • Ambient data in more areas for more pollutants
    • New monitoring technologies that are accessible, transparent and cost effective
    • More research into the cumulative impacts of exposure to air toxics on human health
    • Better integration of air toxics, pollution prevention and voluntary programs in regulatory and non-regulatory efforts
    • Regulatory tools to direct national regulatory efforts at source categories where emissions pose significant risks.


  • Reducing emissions of air toxics has been a priority for EPA since the CAA Amendments of 1990 and the development of the Integrated Urban Air Toxics Strategy in 1999.
  • Between 1990 and 2012 the EPA has issued 97 technology-based standards covering 174 major source categories – including gasoline distribution facilities, chemical plants, petroleum refineries and utilities – that have resulted in significant improvements in air quality across the nation.
  • EPA has also issued rules for 68 area source categories – such as dry cleaners, electric arc furnaces and small PVC manufacturers -- addressing 90 percent of the worst urban HAPs.
  • Mobile source regulations, like the 2007 Mobile Source Air Toxics rule and the recently finalized Tier 3 vehicle and fuel standards, have also achieved substantial air toxic reductions.
  • In addition, national initiatives like the National Clean Diesel Campaign, Burn Wise, the Collision Repair Campaign and SmartWay have further reduced air toxics through voluntary partnerships with industry.  
  • EPA has worked closely with state, local and tribal agencies to promote area-wide and regional strategies to address air toxics and supported a number of community-based programs that help communities understand, prioritize and reduce exposures to toxic pollutants in their local environment.
  • In addition, EPA has initiated and supported a number of community-based programs with a focus on environmental justice, to address local air toxics concerns.


  • Because air toxics tend to pose greater risks in urban areas, it is critical that EPA continue to work in partnership with states, tribes, local governments and communities to ensure ongoing progress in reducing risks.
  • Partnerships with the National Association of Clean Air Agencies, the National Tribal Air Association and the National Environmental Justice Advisory Council are fostering community capacity building and help improve understanding of local air toxics issues.
  • Through planned regional discussions and involvement of EPA’s Clean Air Act Advisory Committee, EPA will hear from states, communities and other stakeholders on how to best address air toxics in the future.
  • Training programs through the Institute for Tribal Environmental Professionals, the online Air Pollution Training Institute and the Environmental Justice community are delivering critical information to state, tribal and local partners that implement air toxics rules.
  • New programs like EPA’s Air, Climate and Energy (ACE) Research Program and NexGen are improving our research on air pollutants and risk assessments to create a more robust system for health effects research.
  • EPA funding for air monitoring initiatives, including monitoring near roadways in larger cities, and grants for community-scale air monitoring, will empower communities and individuals to take action to avoid air pollution exposure using routine and low-cost portable air pollution sensors.
  • EPA’s forthcoming new version of NATA, due out in 2015, will provide communities with more current information on risks from air toxics.
  • These efforts, along with the implementation and adoption of new and existing national rules for stationary and mobile sources, will provide further reductions in air toxics.


  • The 1990 CAA Amendments required EPA to take specific actions to reduce emissions and risks from air toxics. Air toxics (also known as hazardous air pollutants or HAPs) are pollutants known to cause or suspected of causing cancer as well as respiratory, neurological, reproductive and other serious health effects.
  • Most air toxics originate from on-road and off-road mobile sources; major stationary sources, smaller area sources, and indoor sources.
  • In 1999, EPA developed the Integrated Urban Air Toxics Strategy for reducing cumulative public health risks in urban areas posed by the aggregated exposures of air toxics emitted from major stationary sources, smaller area stationary sources and mobile sources. It consists of four key components:
    • Source-specific and sector-based standards
    • National, regional and community-based initiatives
    • National-level air toxics assessments
    • Education and outreach
  • The CAA also required EPA to submit two reports to Congress describing the agency’s actions to reduce public health risks from urban air toxics. The EPA issued the first Urban Air Toxics Report to Congress in 2000.  The Report issued today fulfills the requirement for the second report to Congress.

Printable version of the fact sheet:

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