Nearly Half of Nonsmokers Still Breathing Cigarette Fumes

Nearly half of nonsmoking Americans are still breathing in cigarette fumes, but the percentage has declined dramatically since the early 1990s, according to a government study released Thursday.

The new study found about 46 percent of nonsmokers had signs of nicotine in their blood in tests done from 1999 through 2004. That was a steep drop from 84 percent when similar tests were done in the late 1980s and early 1990s.

But health officials stopped short of celebrating.

"It's still high," said Cinzia Marano, one of the study's authors. "There is no safe level of exposure."

Cigarettes cause lung cancer and other deadly illnesses not only in smokers, but also in nonsmokers who breathe in smoke, studies have shown.

For nonsmoking adults, secondhand smoke increases their lung cancer risk by at least 20 percent and their heart disease risk by at least 25 percent. Children exposed to secondhand smoke are at increased risk of asthma attacks, ear problems, acute respiratory infections and sudden infant death syndrome, health officials say.

More from Fox News