ACOEM Objects to Proposed Changes to EPA National Ambient Air Quality Standard

September 5, 2017

The Honorable John Barrasso
Chair Committee on Environment and Public Works
U.S. Senate Washington, DC 20510

The Honorable Thomas R. Carper
Ranking Member
Committee on Environment and Public Works
U.S. Senate
Washington, DC 20510

Re: S. 263 and S. 452

Dear Chairman Barrasso and Ranking Member Carper:

On behalf of the American College of Occupational and Environmental Medicine (ACOEM), I write to register our strong concerns with both S. 263, the Ozone Standards Implementation Act and S. 452, Ozone Regulatory Delay and Extension of Assessment Length (ORDEAL) Act. Both bills would make significant and, in our opinion, unwarranted changes in how Environmental Protection Agency (EPA) establishes and enforces the National Ambient Air Quality Standard for ozone and other criteria pollutants. If enacted, these pieces of legislation would have significant negative impacts on the health of many Americans.

In 2015, after a decade of careful study, EPA promulgated a rule to improve the air quality standard for ground level ozone from 75 ppb to 70 ppb, effective December 28, 2015. The scientific evidence supporting this improvement was overwhelmingly persuasive then, and has become even more persuasive now, with recent powerful studies showing that ozone causes major health effects at concentrations as low as 50 ppm.1,2,3

To summarize the key public health benefits of improving the ozone standard: for the tens of millions of Americans now living in “non-attainment” areas where ozone concentrations range above 70 ppm, public health experts confidently project that improving the ozone standard will decrease the overall population death rate by 20/100,000 (about 2%), saving hundreds of lives each year, while also averting thousands of annual hospital admissions and improving the lung function of growing children by 5 to 10%.

ACOEM has several grave concerns with both S. 263 and S. 452:
  • A delay in implementation of the EPA ozone standard until 2025 will lead to avoidable adverse health effects, including asthma attacks, COPD exacerbations, missed school and work days, emergency room visits, hospitalizations, and premature death.
  • S. 263 would delay revision of all the criteria pollutants under the Clean Air Act. Instead of reviewing National Ambient Air Quality Standards every 5 years, standards would be revised every 10 years.
If enacted, these bills would delay improvements in air quality and contribute to respiratory harm including asthma exacerbations and premature deaths that could have been avoided. ACOEM respectfully urges the committee to reject S. 263 and S. 452. If you should have any questions or need additional information, contact Patrick O’Connor, ACOEM’s Director of Government Affairs, at 703-351-6222. Thank you for your consideration.


Charles M. Yarborough III, MD, MPH, FACOEM
ACOEM President 


1. Jerrett M, Schwartz J, et al. Long-Term Ozone Exposure and Mortality. New Engl J Med. 2017;360:1085-95.

2. Magzamen S. Ozone-related Respiratory Morbidity in a Low-Pollution Region. J Occup Environ Med. 2017;59:624-30.

3. Drew B. Day, PhD, et al. Association of Ozone Exposure with Cardiorespiratory Pathophysiologic Mechanisms in Healthy Adults. JAMA Internal Medicine. 2017.