EPA Seeks to Tighten Limits for Smog

Stating that the existing standards fail to protect the public from ground-level ozone, EPA proposed a regulation to lower the limit for the primary component of smog by as much as 20 percent in coming decades.

Officials said that the proposal, which would revise the standards for the first time since 1997, is based on the most recent scientific evidence about the health effects of ozone -- the primary component of smog.

"Advances in science are leading to cleaner skies and healthier lives," said EPA Administrator Stephen L. Johnson. "America's science is progressing, and our air quality is improving. By strengthening the ozone standard, EPA is keeping our clean air momentum moving into the future."

The agency' proposal drew criticism from industry groups, which argue that current standards are sufficient, and environmental advocates, which contend the proposal does not go far enough to protect those populations most sensitive to ozone pollution.

"Over the last generation, emissions of key air pollutants have dropped by more than 54 percent," said John Engler, president of the National Association of Manufacturers. "This progress has been made even as our economy, fuel consumption, and population grew. It's a success to industry's commitment to cleaner air.

"We recognize that EPA has a duty to protect public health, and studies have shown implementing the current standard will do just that," Engler added. "Even though a lot has been done and spent, there is still a long way to go to meeting the current standard. Therefore we see no reason to revise the current standard."

David H. Ingbar M.D., president of the American Thoracic Society, called the proposed standards "unhealthy for America's kids, unhealthy for America's seniors, and unhealthy for America."

"The science is clear, ozone pollution is causing unnecessary, illnesses and death in America," Ingbar said. "The proposed EPA standards fall short of providing the protection needed to keep Americans safe from ozone air pollution."

EPA officials said they are particularly concerned about people with asthma or other lung diseases, as well as those who spend a lot of time outside, such as children. Ozone exposure can aggravate asthma, resulting in increased medication use and emergency room visits, and it can increase susceptibility to respiratory infections.

The United States has made significant progress reducing ground-level ozone in the past quarter century, EPA noted. Since 1980, ozone levels have dropped 21 percent nationwide as the federal agency, states and local governments have worked together to continue to improve the nation's air.

Ground-level ozone is not emitted directly into the air, but is created through a reaction of nitrogen oxides and volatile organic compound emissions in the presence of sunlight, EPA stated. Emissions from industrial facilities, electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents are the major human-made sources of these ozone precursors.

The proposal recommends an ozone standard within a range of 0.070 to 0.075 parts per million (ppm). EPA also is taking comments on alternative standards within a range from 0.060 ppm up to the level of the current eight-hour ozone standard, which is 0.08 ppm.

Additionally, EPA is proposing to revise the "secondary" standard for ozone to improve protection for plants, trees and crops during the growing season. The secondary standard is based on scientific evidence indicating that exposure to even low levels of ozone can damage vegetation. EPA is proposing two alternatives for this standard: a standard that would be identical to the "primary" standard to protect public health; and a cumulative standard aimed at protecting vegetation during the growing season.

EPA is estimating the health benefits of meeting a range of alternative ozone standards based on published scientific studies and the opinion of outside experts. These findings will be detailed in a regulatory impact analysis to be released in the next few weeks, which will include both the estimated costs and benefits. EPA projects that health benefits of the proposed standard could be in the billions of dollars. However, the agency does not consider costs in setting ozone standards.

Critics said that the draft ozone pollution regulations fall short of the standard recommended by EPA scientific experts. "The law says use the science, the science says lower the standard to safe levels," said Francesca Grifo, director of the Union of Concerned Scientists' Scientific Integrity Program. "In disregarding its own scientists' analysis, EPA is risking the health of millions of Americans."

Frank O'Donnell, president of the non-profit Clean Air Watch, said that while the good news is that EPA agrees that current smog standards are too weak to protect people's health, "EPA seems to be hedging its bets. It has suggested a range of possibilities. Most disturbingly, it has left open the door to keeping the current standards, which are outdated and don't reflect recent science."

According to the National Petrochemical and Refiners Association (NPRA), EPA's proposed action could carry adverse implications for U.S. companies and consumers. "There is no need to change the current standard because it is working as intended and air quality is improving," NPRA Executive Vice President Charles T. Drevna said. "According to EPA itself, emissions from the six key pollutants dropped 54 percent between 1970 and 2006 even as the economy grew dramatically, and national average ozone levels have dropped 21 percent since 1980. Since the states have not yet fully implemented the current standard, EPA should instead help localities implement the current standard before imposing a brand new one that could result in further negative impacts on American businesses as they attempt to compete in a global marketplace."

The agency will take public comment for 90 days following publication of the proposal in the Federal Register and will hold four public hearings. The hearings will be held in Los Angeles and Philadelphia on Aug. 30, and in Chicago and Houston on Sept. 5.

More information about EPA's proposal for ground-level ozone can be found at http://epa.gov/groundlevelozone.

This article originally appeared in the 06/01/2007 issue of Environmental Protection.

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