How Toxic is LA's Air? Should You Fear For What's Happening to Your Brain?

We all know the dangers of air pollution.  But studies have shown that air pollution could affect more than just your respiratory system.  Past studies have shown that extended exposure, especially in urban environments, can increase the risk of autism in unborn children, and, in a new study, could even cause your brain to shrink over time.

The study was conducted at Beth Israel Deaconess Medical Center and the Harvard T. H. Chan Public School of Public Health by Elissa H. Wilker along with her team of researchers from the Cardiovascular Epidemiology Research Unit.

The new findings, published in the American Heart Association journal Stroke, revealed that long term exposure to air pollution increases the risk of silent stroke by 46 percent, can decrease the size of the brain and its structure by 0.32 percent and may even result in reduced cognition.

For the study researchers used magnetic resonance imaging (MRI) scans on 943 participants who were in good shape to find out just what happens if one is exposed to air pollution over a long period of time.  All of the participants were over 60 and resided in the Boston, New England and New York areas.

The researchers also scanned subjects in the New England area and compared them to the other participants.  For each participant, researchers also examined the varying pollution levels where they reside in order to determine their findings.

The findings revealed that brain volume decreased at a rate of 0.32 percent when the rate of pollution was at 2 micrograms or higher.  This level of pollution could potentially come from car exhaust and other vehicle related pollution. People exposed to high pollution levels were also at a higher risk of experiencing a silent cerebral infarction and researchers found that there was a significant increase in the risk of silent strong by more than 46 percent.

Study author Wilker said it has been found that exposure to air pollution for a long time could affect the brain. Even low levels of exposure could harm older people and those who are relatively healthy. She further said, "We found that people who live in areas where there are higher levels of air pollution had smaller total cerebral brain volume and were more likely to have evidence of covert brain infarcts."

According to Wilker, the researchers have now planned to look at the impact of air pollution over a longer period and its effects on more MRI sensitive measures.