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EPA Strengthens Air Quality Standard for Nitrogen Dioxide

The first new NO<sub>2</sub> standard in 35 years will improve air quality for millions, according to EPA, protecting millions of Americans from peak, short-term exposures that primarily occur near major roads. Short-term exposures to NO<sub>2</sub> have been linked to impaired lung function and increased respiratory infections, especially in people with asthma.

“This new 1-hour standard is designed to protect the air we breathe and reduce health threats for millions of Americans. For the first time ever, we are working to prevent short-term exposures in high risk NO2 zones like urban communities and areas near roadways,” said EPA Administrator Lisa P. Jackson. “Improving air quality is a top priority for this EPA. We’re moving into the clean, sustainable economy of the 21st century, defined by expanded innovation, stronger pollution standards and healthier communities.”

The agency set the new 1-hour standard for NO2 at a level of 100 parts per billion (ppb). EPA also is retaining the existing annual average standard of 53 ppb. NO2 is formed from vehicle, power plant and other industrial emissions, and contributes to the formation of fine particle pollution and smog. Earlier this month, EPA proposed to tighten the nation’s smog standards to protect the health of all Americans, especially children.

EPA is establishing new monitoring requirements in urban areas that will measure NO2 levels around major roads and across the community. Monitors must be located near roadways in cities with at least 500,000 residents. Larger cities and areas with major roadways will have additional monitors. Community-wide monitoring will continue in cities with at least 1 million residents.

Working with the states, EPA will site at least 40 monitors in locations to help protect communities that are susceptible and vulnerable to elevated levels of NO2.

The new standard will help protect Americans from NO2 exposures linked to respiratory illnesses that lead to emergency room visits and hospital admissions, particularly in at-risk populations such as children, the elderly and asthmatics.

“On behalf of the 15,000 members of the American Thoracic Society, I want to thank the EPA for the promulgation of the 1-hour NO2 limit, for which our leadership and members strongly advocated,” said J. Randall Curtis, M.D., M.P.H., president of the ATS, which is an association dedicated to advancing pulmonary, critical care and sleep medicine.

The ATS played an active role in supporting the new stricter standard including publishing an editorial calling for tighter standards in the American Journal of Respiratory and Critical Care Medicine, and submitting written comments and testifying at regional EPA field hearings.

“We were disappointed that EPA did not maximize this opportunity to protect the public health from the dangers of NO2 by issuing a stricter one-hour limit or reducing the annual limit. Nonetheless, the new one-hour standard will undoubtedly prevent many exacerbations of asthma and hospitalizations from NO2-associated respiratory problems,” said Curtis.

EPA expects to identify or designate areas not meeting the new standard, based on the existing community-wide monitoring network, by January 2012. New monitors must begin operating no later than Jan. 1, 2013. When 3 years of air quality data are available from the new monitoring network, EPA intends to redesignate areas as appropriate.

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