Smog Increasing in U.S.A.

Although the amount of smog in the U.S.A. declined in the 1980s, the amount of smog in the 1990s increased despite a nationwide effort to improve air quality, statistics from the Environmental Protection Agency show. According to an article, "One likely reason why the smog isn't lifting: Americans are driving more miles than they did in the 1980s. And they're driving vehicles that give off more pollution than the cars they drove in the '80s."