FORT WORTH (CBSDFW.COM) – For years, fumes from car and truck exhaust have been connected to respiratory, heart, and other health problems.

Now researchers are finding more and more evidence that those fumes could also hurt the brain.

The Wall Street Journal reports today that in new studies, researchers found that breathing the air in a congested city for three months can cause genetic changes in the elderly and in newborns.

“The evidence is growing that air pollution can affect the brain,” said Dr. Heather Volk, a medical epidemiologist at the University of Southern California.

Dr. Volk’s research indicates that children who live near highways in some major California cities are twice as likely to have autism.

“Based on our data, it looks like air pollution might be a risk factor for autism,” she said.  But she added that more research needs to be done, and it’s too soon to panic.

Scientists have also found connections between dirty air and memory problems.  It may also increase the risk for Alzheimer’s disease.

In Texas, the Dallas-Fort Worth area has longstanding problems with elevated ozone levels, a major contributor to air pollution.  The American Lung Association ranks DFW the 12th- worst metro area in the country for ozone levels.  But its particle pollution levels are not even in the top 25.

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