Secondhand Smoke, Not Safe:

What’s a safe level of exposure to secondhand smoke? You may assume limited exposure does little harm. But a new Surgeon General report finds that any exposure poses a risk. Smokers inhale toxins when they puff on a cigarette, but evidence shows that breathing secondary smoke does even more damage. Non-smokers exposed to secondhand smoke face a 20 to 30 percent increased risk of heart disease and lung cancer. The report, which many may find controversial, recommends banning smoking indoors, not segregating smokers and installing ventilation systems.

Source: www.surgeongeneral.gov/library/secondhandsmoke