TALKING POINTS. Ten Reasons Why the Ozone Air Quality Standard Must Be Strengthened

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1 October 22, 2014 TALKING POINTS Ten Reasons Why the Ozone Air Quality Standard Must Be Strengthened 1. The current standard is not protective of public health. The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) that will protect public health, including the health of sensitive populations, with an adequate margin of safety. The current 8 hour average standard of 75 ppb is above the level proven to harm the lungs. Populations at risk include children, the elderly, people with asthma, and otherwise healthy individuals that work or exercise outdoors. People with pre existing respiratory diseases are at increased risk because they have less pulmonary reserve and cannot tolerate the reduction in lung function or the increase in respiratory symptoms. More than 25 million people in the United States have asthma, 74 million are children, and 40 million are senior citizens. There are nearly 17 million outdoor workers. Based on age criteria alone, more than one third of the population is at increased risk of adverse effects from ozone air pollution The EPA Clean Air Scientific Advisory Committee (CASAC) has repeatedly recommended an 8-hour ozone standard in the range of 60 to 70 ppb. 2 In their most recent letter to the EPA Administrator, the CASAC made clear that: The current standard is inadequate to protect public health. At 70 ppb, there is substantial evidence of adverse effects including decrease in lung function, increase in respiratory symptoms, and increase in airway inflammation. A standard of 70 ppb provides little margin of safety and advised that the standard should be set below this level to meet the statutory requirement in the Clean Air Act to protect public health with an adequate margin of safety. 1 U. S. EPA. Policy Assessment for the Review of the Ozone National Ambient Air Quality Standards. EPA 452/R , August 2014, pp to Letter from Christopher Frey PhD, Chair Clean Air Scientific Advisory Committee to EPA Administrator Gina McCarthy, EPA CASAC , CASAC Review of the EPA s Second Draft Policy Assessment for the Review of the Ozone National Ambient Air Quality Standards, June 26, 2014.

2 2 60 ppb is the most protective option, and the only option that would certainly provide an adequate margin of safety. 3 According to the CASAC:... there is a causal relationship between short-term ozone exposure and a broad range of respiratory effects, including lung function decrements, respiratory symptoms, inflammation, hospital admissions, and emergency department visits, all of which are observed below the level of the current ozone NAAQS. The CASAC concludes that there is adequate scientific evidence to recommend a range of levels for a revised primary ozone standard from 70 ppb to 60 ppb. The frequency of lung function decrements and premature mortality from shortterm exposure to ozone decreases even further when the alternative standard is lowered to 60 ppb. 3. The EPA s Children s Health Protection Advisory Committee recommends a revised ambient air quality standard of 60 ppb to protect the health of children. 4 According to the Committee: Children suffer a disproportionate burden of ozone-related health impacts due to critical developmental periods of lung growth in childhood and adolescence that can result in permanent disability. 4. The Integrated Science Assessment completed in 2013 finds stronger evidence of the adverse effects of short- and long-term exposure to ozone for many health endpoints. 5 The key new findings include: a conclusive determination that ozone causes adverse respiratory effects several new controlled human exposure studies (in healthy young adults) demonstrating respiratory deficits and inflammation at 60 ppb stronger findings that the adverse effect of ozone on cardiovascular health are likely causal 3 Letter from Christopher Frey PhD, Chair Clean Air Scientific Advisory Committee to EPA Administrator Gina McCarthy, EPA CASAC , CASAC Review of the EPA s Health Risk and Exposure Assessment for Ozone (Second External Review Draft, February 2014, July 1, Letter from Sheela Sathyanarayana MD, MPH, Chair, Children s Health Protection Advisory Committee (CHPAC) to Christopher Frey PhD, Chair, US EPA Clean Air Scientific Advisory Committee, May 19, U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). EPA/600/R 10/076F, 2013.

3 3 new information suggesting reproductive effects such as increased risk of low birth weight babies suggestive neurological effects new community health studies strengthening the link between ozone exposure and mortality, even at concentrations below the current standards new information about the impact of longer term exposures on respiratory health endpoints such as pulmonary inflammation and injury, and new onset asthma 5. The Risk and Exposure Assessment estimates that a revised standard level of 60 ppb would reduce children s exposures of concern by 95 to 100% compared to the current standard. 6 In contrast, a standard of 70 ppb would reduce exposures of concern by only percent, and a standard of 65 would reduce the occurrence of such exposures by just 30 to 65 percent. 6. After a comprehensive six-year review, EPA staff scientists conclude that the current standard is not protective of public health and recommend a standard in the range of 60 to 70 ppb in the 2014 Policy Assessment. 7 Staff reaches the overall conclusion that the available health evidence and exposure/risk information call into question the adequacy of the public health protection provided by the current standard. 7. Controlled human exposure studies provide strong evidence that healthy young adults experience diminished breathing capacity and airway inflammation at ozone concentrations of 60 ppb. 8 The physiological effects demonstrated at 60 pbb are linked to aggravation of asthma, increased susceptibility to respiratory infection, increased use of medication, more school and work absences, doctor visits, and emergency room visits. Sensitive populations such as children and people with asthma would likely experience these effects at even lower concentrations. People with pre existing lung disease such as COPD have lower ventilatory reserves, and ten percent declines in lung function of can lead to moderate to severe respiratory symptoms. 6 U.S. EPA. Health Risk and Exposure Assessment for Ozone Final Report, EPA 452/R f, August U. S. EPA. Policy Assessment for the Review of the Ozone National Ambient Air Quality Standards. EPA 452/R , August Kim CS, et al Lung function and inflammatory responses in healthy young adults exposed to 0.06 ozone for 6.6 hours. Am J Respir Crit Care Med 183: Brown JS et al Effects of exposure to 0,06 ppm ozone in FEV1 in humans: A secondary analysis of existing data. Environ Health Perspect 116:

4 4 8. Laboratory toxicology studies airways of infant monkeys exposed to ozone air pollution have structural changes in the respiratory tract. 9 The majority of the lung s airways develop after birth and continues to age 18 20, thus morphological changes portend life long impairment. Structural and cellular changes could contribute to airway obstruction and hyperresponsiveness, the hallmark features of asthma. 9. Epidemiological studies provide evidence that ozone increases risk of emergency room visits and hospital admissions for respiratory problems, and even premature death. The most compelling studies are those that report associations with ozone in areas that meet the current air quality standards. Multicity studies in less polluted areas of Canada report positive associations with morbidity and mortality even when the majority of study locations would have met the current ozone standard. 10 A study in Seattle reported associations between ozone and asthma emergency department visits in an area that would have met current standards during the entire study period. 11 A study of pediatric asthma emergency visits in Atlanta found no evidence of a threshold down to concentrations of 30 ppb ozone, with the greatest statistical confidence at 55 ppb. 12 A study of asthma hospital admissions in New York City reported positive associations with ozone, even when over 99 percent of the days would have met the current standard. 13 Panel studies of children and outdoor workers report respiratory effects at ambient concentrations lower than 60 ppb Fanucci MV et al Cyclic exposure to ozone alters the distal airway development in infant rhesus monkeys. Am J Physiol Lung Cell Mol Physiol 291: L644 L Dales RE et al Gaseous air pollutants and hospitalization for respiratory disease in the neonatal period. Environ Health Perspect 114: Cakmak S et al Respiratory health effects of air pollution gases: Modification by education and income. Arch Environ Occup Health 61: Katsouyanni K et al Air pollution and health: A European and North American approach (APHENA). Health Effects Institute Research Report Mar TF and Koenig JQ Relationship between visits to emergency departments for asthma and ozone exposure in greater Seattle, Washington. Ann Allergy Asthma Immunol 103: Strickland MJ et al Short term associations between ambient air pollutants and pediatric asthma emergency department visits. Am J Respir Crit Care Med 182: Silverman RA and Ito K Age related association of fine particles and ozone with severe acute asthma in New York City. J Allergy Clin Immunol 125: Brauer M et al Effect of ambient ozone exposure on lung function in farm workers. Am J Respir Crit Care Med 154: Brunekreef B et al Respiratory effects of low level photochemical air pollution in amateur cyclists. Am J Repir Crit Care Med 150:

5 5 Epidemiological studies show increased risk of premature death associated with short term ozone exposures, even when days with concentrations above 60 ppb are excluded from the analysis The air quality alert system is misleading the public. Reporting of bad air days is based on the current outdated standard. The public has a right to know when the air is hazardous to health. The Air Quality Index must be updated consistent with current understanding of levels that are adverse to sensitive populations and the general public. 15 Bell ML et al The exposure response curve for ozone and risk of mortality and adequacy of current ozone regulations. Environ Health Perspect 114: