The U.S. Environmental Protection Agency (EPA) is making the most recent data available on the state of the nation’s air quality, according to an agency press release. Air pollution impacts public health, the environment, and the Earth’s climate, and understanding these impacts are important priorities for the agency. EPA regulatory actions and voluntary efforts have led to cleaner cars, industries and consumer products, which in turn have contributed to improvements in the nation's air.

Since 1990, nationwide air quality has improved significantly for the six common air pollutants: ground-level ozone, particle pollution, lead, nitrogen dioxide, carbon monoxide, and sulfur dioxide. Emissions of toxic air pollutants, such as benzene, have declined about 40 percent nationwide between 1990 and 2005.

These reductions are helping to improve public health by decreasing the number of emergency room visits, respiratory illnesses, and premature deaths. Positive impacts can also be seen in the environment, with regional haze decreasing.

Despite this progress, about 127 million Americans live in counties violating at least one of the national air quality standards. The agency has taken recent actions to tighten air quality standards to help ensure improvements in air quality for everyone.

EPA’s most recent evaluation of air pollution, Our Nation’s Air, Status and Trends Through 2008, presents trends in air quality measurements, analyzes national emissions from key industrial sectors and takes a look at the relationship between air quality and climate change.

For more information, visit http://www.epa.gov/airtrends.