June 4th, 2010

First new SO2 standard in 40 years expected to improve air quality for millions

From Green Right Now Reports

The U.S. Environmental Protection Agency yesterday issued a new health standard for sulfur dioxide (SO2)  to protect Americans from short-term exposure to SO2. The chemical compound is primarily emitted from power plants and other industrial facilities.

Exposure to SO2 can aggravate asthma and cause other respiratory difficulties. People with asthma, children, and the elderly are especially vulnerable to the effects of SO2, the EPA says.

“We’re taking on an old problem in a new way, one designed to give all American communities the clean air protections they deserve. Moving to a one-hour standard and monitoring in the areas with the highest SO2 levels is the most efficient and effective way to protect against sulfur dioxide pollution in the air we breathe,” EPA Administrator Lisa P. Jackson, said in a statement. “This is one of many pollutants we’ve been able to significantly reduce through the Clean Air Act, keeping people healthy, protecting our environment and growing our economy.”

The EPA is setting the one-hour SO2 health standard at 75 parts per billion (ppb), a level designed to protect against short-term exposures ranging from five minutes to 24 hours. The agency is revoking the current 24-hour and annual SO2 health standards because it says the science indicates that short-term exposures are of greatest concern and the existing standards would not provide additional health benefits.

The monitoring requirements for SO2 also are being changed. The new requirements assure that monitors will be placed where SO2 emissions impact populated areas. Any new monitors required by this rule must begin operating no later than Jan. 1, 2013. EPA is expecting to use modeling as well as monitoring to determine compliance with the new standard.

The final rule also changes the Air Quality Index to reflect the revised SO2 standard. This change will improve states’ ability to alert the public when short-term SO2 levels may affect their health.

The EPA estimated that the health benefits associated with this rule range between $13 billion and $33 billion annually. These benefits include preventing 2,300 to 5,900 premature deaths and 54,000 asthma attacks a year. The estimated cost in 2020 to fully implement this standard is approximately $1.5 billion.

The first National Ambient Air Quality Standards for SO2 were set in 1971, establishing both a primary standard to protect health and a secondary standard to protect the public welfare. Annual average SO2 concentrations have decreased by 71 percent since 1980.

EPA plans to identify areas not meeting the new standard by June 2012.