EPA Strengthens Nitrogen Dioxide Rules for First Time in 35 Years

The Environmental Protection Agency (EPA) today announced a new "one-hour standard" aimed at limiting Americans' short-term exposure to nitrogen dioxide (NO2), a pollutant created by cars, power plants, and other industrial sources.

(Photo: TreeHugger)

NO2, a main ingredient in smog, is linked to adverse respiratory health effects such as chronic asthma. In creating a new one-hour NO2 exposure limit of 100 parts per billion (ppb), the EPA noted that the risk of short-term NOX exposure is particularly acute near major highways.

As EPA chief Lisa Jackson said in a statement:

The rule will be enforced by setting up monitors near roads in areas with more than 500,000 residents, according to the agency, with a deadline of 2013 for the beginning of pollutant tracking. The EPA said it plans to work directly on 40 new monitors for cities and towns with the most significant NO2 exposure.

It's worth noting, however, that major cities have remained out of compliance with EPA air-quality standards for years without losing significant amounts of federal highway money, as the federal government often threatens. Moreover, the EPA has not changed the current annual NO2 standard of 53 ppb.