Strict EPA rules tag unlikely areas

Smaller metropolitan areas -- not gritty urban centers -- are the most likely to be labeled as smoggy under a strict definition that the Environmental Protection Agency announced last month, an analysis by USA TODAY found.

The new limit also would ensnare many communities that contain large expanses of pristine wilderness. Places that would fall under the new ozone limit include Boise; Bar Harbor, Maine; and Biloxi, Miss.

Pollution from cars and other sources forms smog. Under the EPA's old limit, set in 1997, air was unhealthy if it had an average of more than 84 parts per billion of ozone. The new limit is 75 parts per billion or more.

The National Research Council today -- on Earth Day -- will release a report on smog-related deaths.

The new EPA limit takes effect in two years. Using the 2004 to 2006 data, the most recently available, the USA TODAY analysis shows: ...