Some political activists assert that the Charlotte region's air quality is horrible and likely to get worse without aggressive new regulations.

In fact, by any reasonable measure, Charlotte's air quality is good and getting better.

The Charlotte metropolitan area complies with EPA standards for carbon monoxide, nitrogen dioxide, sulfur dioxide, lead and airborne particulates, including tough new particulate standards implemented last year.

Ozone is Charlotte's only remaining air pollution challenge. Six of the region's eight monitoring sites violate the stringent ozone standard EPA implemented last year. Nevertheless, the region has a good chance of meeting the standard within the next several years.

There are other air pollutants for which EPA has no specific standards, but these are declining as well. For example, motor vehicles are the largest source of benzene and 1,3-butadiene. However, emissions of these two pollutants declined about 50 percent during the last decade. Soot emissions from diesel trucks are declining at a similar rate. Already adopted requirements ensure that these improvements will continue.

EPA tightened automobile standards in 1994, 2001 and 2004. Most of the benefits--the 2004 standards require a 90 percent pollution reduction compared to the current average vehicle on the road--won't be fully realized until more than a decade from now, as older models are progressively retired. On-road measurements show average auto emissions continue to drop about 10 percent per year, providing real-world confirmation of the expected improvements. Even in rapidly growing areas such as Charlotte, automobiles are getting cleaner far faster than total driving is increasing, and this trend will continue.

During the last decade, EPA adopted similarly tough standards for new on- and off-road heavy diesels that will phase in over the next few years. Federal and state caps on power plant and other factory pollution have eliminated most industrial emissions and will achieve large additional reductions over the next two decades. Taken together, these measures will eliminate the vast majority of remaining air pollution.

If air quality is so good, why does it seem so bad? A key reason is that activists, regulators and the news media exaggerate air pollution levels and health risks and obscure positive trends.

For example, regulators announce "code orange" or "code red" days when ozone is projected to exceed federal standards. The American Lung Association hands out failing grades to most of the nation, including Charlotte, each year in its methodologically useless "State of the Air" reports. The Observer has helped create this false impression through stories with headlines like "Traffic is choking Charlotte's air."

You wouldn't know from these reports that Charlotte meets all air pollution health standards save for ozone or that EPA's own scientists have shown that ozone has little health impact at current and recent levels. For example, according to EPA's estimates published in the prestigious journal Environmental Health Perspectives, going from ozone levels in 2002--the worst among recent years--to attainment of EPA's stringent new ozone standard would reduce respiratory hospital admissions by only 0.07 percent and asthma emergency room visits by 0.04 percent.

Air pollution affects far fewer people, far less often and with far less severity than suggested by the air pollution alert system or the unwarranted alarmism typical of media and activist reports. And whatever the current harm from air pollution, existing requirements will mitigate most of it in coming years. In terms of air pollution's effects on health, it is time to declare victory.

Joel Schwartz is  a visiting fellow at AEI.