Since the Clean Air Act was enacted in 1970, efforts to reduce ozone have concentrated on reducing, first, the volatile organic compounds, and only more recently, the nitrogen oxides. EPA has been tracking NOx and five other major air pollutants since 1970, and found that while carbon monoxide, lead, particulate matter, sulfur dioxide, and volatile organic compounds have decreased significantly, NOx emissions have increased approximately 17 percent.16 Reductions in VOCs have resulted in improved ozone levels: aggressive national programs tackling ozone have reduced 8-hour ozone levels nationwide by 11percent from 1982 to 2001.

However, ozone levels in some parts of the country actually increased in the decade of the 1990s, evidence that more aggressive steps were needed, especially targeting NOx. Wind can carry ozone hundreds of miles, so people who don’t live in areas with high levels of VOC and NOx emissions aren’t necessarily safe from these emissions. The Clean Air Act contains provisions that have allowed states to target significant sources of pollutants like NOx far from their borders that are contributing to their high ozone levels.17 Several states have used those provisions to challenge pollution in other states. In addition, EPA launched a call for reduced NOx emissions in many Eastern and Midwestern states that have high emissions from coal-fired power plants. The requirements from these actions won’t be fully felt until after 2004.18

Ozone levels can be effectively reduced, using a combination of federal, state, and local efforts. For example, the adoption of new federal emissions standards and cleaner fuel requirements to reduce the emissions of ozone-forming pollutants from construction equipment and other large non-road engines would make a major contribution to healthier air quality. State goverments can fund more transit options in growing urban and suburban areas. City and county officials can plan development patterns that encourage walking and transit use.

In Appendix B, regional differences in ozone are discussed, including trends and sources of VOCs
and NOx.

The Clean Air Act: Under Fire

Since the passage of the Clean Air Act in 1970, Americans have been slowly but surely moving
toward cleaner air. Human exposure to many dangerous pollutants has declined significantly due to federal,
state, and local enforcement of the Act. The Clean Air Act has been one of our nation’s most successful
environmental laws.19

Unfortunately, as we demonstrate in American Lung Association State of the Air: 2003, our air is
still too polluted in too many places, putting the nation’s health at risk.

The American Lung Association is greatly concerned about roadblocks to continued progress
toward cleaner air. Threats to the Clean Air Act come from two areas: continued delays in implementing
the 1997 ozone standards and proposals to roll back key provisions of the Clean Air Act.

Failure to Follow Clean Air Act Requirements

Delay in Enforcing the Standards. The Clean Air Act mandates EPA to review ozone standards every five years. In 1997, the EPA issued a revised National Ambient Air Quality Standard for ozone, in large part due to constant legal pressure from the American Lung Association. This standard resulted from the most strenuous review of the science ever undertaken by the agency, and included more than 3,000 studies. The 1997 ozone standard averages ozone concentration over 8 hours and was intended to replace the 1-hour standard in effect since 1979. Research has shown that lower levels of ozone which occur over long periods, such as 8 hours, harm human lungs. The 1-hour standard only protects against peak exposure; the 8-hour standard protects against those lower, but more pervasive, chronic levels of ozone, while at the same time generally addressing those peak periods.

Monitoring systems in a trailer in Vermont. Courtesy of the Vermont Department of Environmental Conservation.

 The EPA identified many annual health benefits of this more protective standard in 1997. Among them
were: one million fewer cases of reduced lung function in children; hundreds of thousands fewer
instances of aggravated coughing and other serious respiratory symptoms; and thousands fewer visits to
emergency rooms and admissions to hospitals for people with asthma.

Numerous industry groups sued EPA to challenge the standards. The D.C. Circuit ruled in May 1999 that
EPA’s interpretation of the Clean Air Act was unconstitutional, but the American Lung Association, EPA,
and two states appealed this ruling to the Supreme Court. On February 27, 2001, the Supreme Court unanimously struck down the Court of Appeals’ constitutional ruling, and sent the case back for further proceedings. The Supreme Court affirmed that the EPA had the authority to implement the 8-hour standard, but directed the agency to reconsider its implementation approach. On March 26, 2002, the Court of Appeals upheald the 1997 air pollution standards, effectively ending the five-year legal battle as to their validity. EPA is still in the process of addressing another aspect of the Supreme Court’s ruling–specifically, the Court’s directive that EPA reexamine its approach to implementing the 1997 ozone standard.20

The EPAwas required by law to designate “nonattainment areas” for the new ozone standard by 2001. A
nonattainment area is one or more counties that have air dirtier than the national standards for a specific
pollutant. Once the EPA designates a nonattainment Standards that are not enforced do not protect
our citizens.

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