Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (2016 Final Report)

Notice

The U.S. EPA is announcing the availability of the final Integrated Science Assessment for Oxides of Nitrogen – Health Criteria as described in a January 28, 2016 Federal Register Notice.


Abstract

This final report provides the U.S. EPA’s evaluation and synthesis of the most policy-relevant science related to the health effects of gaseous oxides of nitrogen. It provides a critical part of the scientific foundation for the U.S. EPA’s decision regarding the adequacy of the current primary (health-based) national ambient air quality standards for nitrogen dioxide.

The references considered for inclusion in or cited in the first and second external review drafts of the Integrated Science Assessment (ISA) as well as the final ISA are available at http://hero.epa.gov/oxides-of-nitrogen.

Oxides of nitrogen are one of six principal (or criteria) pollutants for which the U.S. EPA has established national ambient air quality standards (NAAQS). For gaseous oxides of nitrogen, the NAAQS are specified in terms of nitrogen dioxide (NO2). The Clean Air Act requires the U.S. EPA to periodically review the scientific basis for these standards by preparing an ISA. These reviews play a significant role in the U.S. EPA’s commitment to ensuring a clean and healthy environment for the public. The Clear Air Scientific Advisory Committee, an independent panel of scientific experts mandated by Section 109(d) of the Clean Air Act, is charged with independent scientific review of the U.S. EPA’s air quality criteria.

This report is part of the Agency’s periodic review of the primary (health-based) NAAQS for NO2. Overall, findings integrated from previous and recent studies strengthen the conclusions from the previous NAAQS review, which was completed in 2010. The cumulative body of evidence indicates that short-term exposure to NO2 can cause respiratory effects, in particular, effects related to asthma exacerbation. Recent results also strengthen the evidence that the respiratory effects of short-term NO2 exposure are independent of the effects of many other traffic-related pollutants. There is now stronger evidence for a relationship between long-term exposure to NO2 and respiratory effects, particularly the development of asthma in children. Results suggest that short-term exposure to NO2 may be associated with cardiovascular effects and premature mortality and that long-term exposure may be associated with cardiovascular effects, diabetes, poorer birth outcomes, premature mortality, and cancer; however, it is uncertain whether NO2 exposure has an effect on these health outcomes that is independent from the effects of other traffic-related pollutants.

Citation

U.S. EPA. Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (2016 Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-15/068, 2016.

History/Chronology

Jul 2008The U.S. EPA released the Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (Final Report) (EPA/600/R-08/071). [Federal Register Notice Jul 11, 2008]
Mar 2012The U.S. EPA held a workshop entitled "Kickoff Workshop to Inform EPA's Review of the Primary NO2 NAAQS'" co-organized by the EPA/ORD/NCEA and the EPA/OAQPS Staff to help with the development of future products on this subject matter. The workshop was held February 29 - March 1, 2012, in Research Triangle Park, North Carolina. [Federal Register Notice Feb 10, 2012]
May 2013The U.S. EPA released the Draft Plan for the Development of the Integrated Science Assessment for Oxides of Nitrogen - Health Criteria. [Federal Register Notice May 3, 2013]
Jun 2013The U.S. EPA’s Science Advisory Board’s CASAC announced a June 2013 consultation by the Oxides of Nitrogen Review Panel on the draft plan for the development of the ISA. [Federal Register Notice May 9, 2013]
Jun 2013The U.S. EPA held a public workshop to review initial draft materials to inform the development of the upcoming Integrated Science Assessment for Oxides of Nitrogen – Health Criteria. [Federal Register Notice May 10, 2013]
Nov 2013The U.S. EPA released the Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (First External Review Draft) for public review and comment. [Federal Register Notice Nov 22, 2013]
Feb 2014The U.S. EPA released the Integrated Review Plan for the Primary National Ambient Air Quality Standards for Nitrogen Dioxide (External Review Draft). [Federal Register Notice Feb 6, 2014 ]
Mar 2014The U.S. EPA's Science Advisory Board's CASAC announced a meeting for the Oxides of Nitrogen Review Panel regarding the review of the first external review draft ISA and the draft Integrated Review Plan. [Federal Register Notice Feb 13, 2014]
Jun 2014The U.S. EPA released the Integrated Review Plan for the Primary NAAQS for Nitrogen Dioxide – Final. [Federal Register Notice Jun 30, 2014]
Jan 2015The U.S. EPA released the Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (Second External Review Draft) for public review and comment. [Federal Register Notice Jan 30, 2015]
Mar 2015The U.S. EPA announced an extension of the public comment period until April 30, 2015. [Federal Register Notice Mar 20, 2015 ]
Jun 2015The U.S. EPA's Science Advisory Board's CASAC announced a meeting for the Oxides of Nitrogen Review Panel regarding the review of the second external review draft ISA. [Federal Register Notice Apr 24, 2015]
Jan 2016The U.S. EPA released the Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (Final Report) (EPA/600/R-15/068). [Federal Register Notice Jan 28, 2016]