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Annenberg School of Communication and Journalism University of Southern California

Study Shows Traffic Pollution May Lead to Stroke

Traffic-related pollution may increase the chances of a stroke according to a stroke center in Boston. 

Moderate levels of traffic-related pollution may increase the chances of a stroke according to new research out of a stroke center in Boston.

Dr. William Mack, a neurosurgeon at Keck Hospital of USC, is now working on his own study in Los Angeles on the effects traffic-related pollutants could have on a stroke.

“They found that times that the amount of pollution in the air is higher and considered a moderate level patients were more likely to have strokes than when the pollution was low and considered a good level,” said Dr. Mack.

“What I’m interested in looking at is how the nanoparticles and the pollution affects the brains ability to get blood and oxygen,” he added.

Dr. Mack said nanoparticles could enter the body through the lungs or nostrils and then get absorbed into the bloodstream. Once they enter the bloodstream they are able to penetrate the brain and if they block the brain from getting blood, they then cause a stroke.

These particles of pollution may be so small that they can enter the brain through the blood brain barrier, an obstacle between the brain tissue and circulating blood that works to protect the brain.

Dr. Mack said because most of these small particles of pollution come from exhaust from cars, Los Angeles might have a higher risk than other cities.

Sam Atwood, spokesman for the Air Quality Management District said Los Angeles has had “the worst air pollution in the country” for decades.

 “We do have many days where it’s not just moderate but it’s actually unhealthy. Last year we had over 100 days in which the air quality was unhealthy,” said Atwood.

Atwood said these high pollution days pose many health risks ranging from stroke or heart attacks to asthma attacks.

“The state of California has estimated that because of fine particulate pollution there are at least 5,000 excess premature deaths here in the Los Angeles region every year,” said Atwood.

Atwood said people who live, work or go to school near areas of high traffic suffer the highest levels of exposure. He said there is only one way to get rid of pollution health risks.

“What really needs to be done is to reduce the sources of air pollution so that we can all breathe healthier air,” said Atwood.

In the mean time, Atwood suggested people with a higher risk of heart attack or stroke pay extra attention to air quality forecasts and try to limit their exposure on days that are unhealthy.

Fred Voza, 57, had his heart valve replaced when he was 49.

“Because I have an artificial valve I have a high propensity to get a stroke,” said Voza.

 I have to be on blood thinners the rest of my life,” he added.

Voza said his blood does not flow smoothly through his blood vessels, which makes blood clots more likely.

“My quality of life is not as good as it used to be physically or mentally,” said Voza.

He said he is always concerned about what may cause a stroke.

“Any kind of pollution whatever it might be is always a cause for concern,” he said.

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