Six Critical Air Pollutants Down in 2006

Six Critical Air Pollutants Down in 2006

WASHINGTON, DC, (ENS)

30th April 2007

Preliminary air quality and emissions data for 2006 shows continued improvement in the nation's air quality over the long term, according to the latest figures from the U.S. Environmental Protection Agency, EPA, released today.

Under the Clean Air Act, the EPA sets national air quality standards for six key pollutants - nitrogen dioxide, ozone, sulfur dioxide, particulate matter, carbon monoxide and lead. Emissions of these six pollutants have dropped by more than half since 1970 and the national average concentration for each criteria pollutant is below the level of its air quality standard.

While national average concentrations of the six key pollutants are below national standards, results vary by site, and annual levels at some individual sites do remain above one or more of the national air quality standards, the EPA said. Annual pollution levels at some monitoring sites do remain above one or more of the national air quality standards, with ozone and particulate matter remaining as the most persistent problems.

Carbon monoxide levels show the greatest improvement, down 62 percent from 1990 levels; lead is down 54 percent and sulfur dioxide is down 53 percent from 1990 levels.

The EPA points out that while emissions of the six key pollutants and the compounds that form them continue to decline, the United States has continued to grow and prosper. To view more detailed figures, click here.