This is your brain ... on traffic fumes? A growing body of research suggests that fumes from traffic jams can damage the brain, as well as your lungs. Exposure to exhaust has a negative effect on brain power and emotional stability, and while the evidence is largely circumstantial, researchers tell the Wall Street Journal it's enough to cause real concern. One study released last year found that children born to mothers living near freeways in Los Angeles were twice as likely to develop autism.
"There are more and more scientists trying to find whether and why exposure to traffic exhaust can damage the human brain," says an epidemiologist studying the effects of traffic pollution on the brains of thousands of women in 22 states. "The human data are very new." Researchers recently discovered that breathing street-level fumes for just half an hour can increase activity in the areas of the brain responsible for decision-making and personality. But there is some good news for those who find themselves stuck in traffic on a regular basis: Today's vehicles only generate around a tenth as much pollution as the cars and trucks that were on the road in 1970. (Read more brain damage stories.)