In Brief: Secondhand smoke and the brain
A federally funded study has found that inhaling secondhand smoke affects the brain in much the same way as smoking a cigarette does.
We've long known that people who smoke cigarettes put more than their own health at jeopardy. The Centers for Disease Control and Prevention estimates that secondhand smoke kills about 50,000 Americans each year.
Exposure to secondhand smoke also increases the likelihood that children will start smoking cigarettes when they become teenagers and makes it harder for adult smokers to quit. Researchers theorized that this might reflect some effect of secondhand smoke on the brain, but until recently they did not understand the biological basis for the relationship.