EPA announces new short-term nitrogen dioxide standard

Nick Snow
OGJ Washington Editor

WASHINGTON, DC, Jan. 26 -- The US Environmental Protection Agency announced a new national air quality standard for short-term exposures to nitrogen dioxide. Both the American Lung Association and American Petroleum Institute responded critically.

The new 1-hr standard of 100 ppb is directed at short-term NO₂ exposures occurring primarily near major highways, the agency said. It added that it is retaining the 53 ppb average annual NO₂ standard.

EPA said it plans to establish new monitoring requirements in urban areas to measure NO₂ levels around major roads and across communities. Cities with at least 500,000 residents will be required to place monitors near roadways. Larger cities and areas with major highways will have additional monitors. Community-wide monitoring will continue in cities with at least 1 million residents.

NO₂ is formed from vehicle, power plant, and other industrial emissions, and contributes to formation of fine particle pollution and ground-level ozone, commonly called smog, according to EPA. It proposed the strictest federal smog control standards yet on Jan. 7 (OGJ Online, Jan. 7, 2010).

“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 agency said in a statement.

EPA said it expects to identify or designate areas not meeting the new standard based on existing community-wide monitors, by January 2012, and will require new monitors to begin operating by Jan. 1, 2013. It also plans to redesignate areas when 3 years of air quality data are available from the new monitoring network.

ALA said in a statement that it was pleased that EPA acted. “But after waiting 38 years, we had frankly hoped for a stronger, more-protective standard,” it continued. “[EPA’s] decision allows areas to have NO₂ concentrations that remain hazardous to the millions of people who will have to breathe them. [Its] final decision, unlike [its] proposal of last summer, allows twice as many days when NO₂ will spike to dangerous levels.”

API issued a statement saying it was “deeply concerned” with the new short-term standard, which it said was based on faulty science. “There is no significant evidence that the short-term NO₂ standard established today by the [EPA Administrator Lisa P. Jackson] is necessary to protect public health. EPA is over-regulating this air-quality standard for political, not health, reasons,” it maintained.
“National ambient NO₂ concentrations are well below the current annual standard, and will continue to be reduced with new industrial and motor vehicle requirements irrespective of this new standard.”

Contact Nick Snow at [email protected].