Sitting in traffic for just 2 hours can lead to brain damage

VANCOUVER, British Columbia — Breathing in diesel exhaust fumes while sitting in traffic could be disastrous for your brain, a new neuroscience study warns. A team at the University of British Columbia says brain scans show increased impairments in brain function after exposure to traffic pollution. In fact, signs of decreased brain function can start to appear in as little as two hours.

The study focused on a person’s functional connectivity — a measure that tests how well different brain regions interact with one another. According to the study authors, this is the first controlled experiment to show evidence of humans showing altered brain network connectivity as a result of air pollution exposure.

“For many decades, scientists thought the brain may be protected from the harmful effects of air pollution,” says Chris Carlsten, a professor and head of respiratory medicine and the Canada Research Chair in occupational and environmental lung disease at UBC, in a university release. “This study, which is the first of its kind in the world, provides fresh evidence supporting a connection between air pollution and cognition.”

The team briefly exposed 25 healthy adults to either diesel exhaust or filtered air in a lab. They used functional magnetic resonance imaging (fMRI) to measure their brain activity before and after each exposure. One of the areas they looked at for possible changes is the brain’s default mode network (DMN). The DMN includes several brain regions connected together that play a part in people’s internal thoughts and memories. The fMRI scans show that people exposed to diesel exhaust have lower DMN activity compared to the air-filtered group.

Collection of brain scans showing decreased activity
fMRI shows decreased functional connectivity in the brain following exposure to traffic pollution. (Credit: University of British Columbia)

“We know that altered functional connectivity in the DMN has been associated with reduced cognitive performance and symptoms of depression, so it’s concerning to see traffic pollution interrupting these same networks,” explains study first author Jodie Gawryluk, a psychology professor at the University of Victoria. “While more research is needed to fully understand the functional impacts of these changes, it’s possible that they may impair people’s thinking or ability to work.”

The good news is that the neurological effects from diesel exhaust were temporary. Every person exposed to air pollution had their brain activity return to normal. However, the study authors speculate that long-term exposure, like sitting in gridlock traffic every day, may cause more permanent damage. While we don’t know how much car exhaust could cause long-lasting brain damage, Dr. Carlsten says it’s better to minimize any exposure in the first place.

“People may want to think twice the next time they’re stuck in traffic with the windows rolled down,” says Dr. Carlsten. “It’s important to ensure that your car’s air filter is in good working order, and if you’re walking or biking down a busy street, consider diverting to a less busy route.”

The study is published in Environmental Health.

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About the Author

Jocelyn Solis-Moreira

Jocelyn is a New York-based science journalist whose work has appeared in Discover Magazine, Health, and Live Science, among other publications. She holds a Master’s of Science in Psychology with a concentration in behavioral neuroscience and a Bachelor’s of Science in integrative neuroscience from Binghamton University. Jocelyn has reported on several medical and science topics ranging from coronavirus news to the latest findings in women’s health.

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  1. sounds like a way to get rid of gas cars…
    scare people
    1. no one has died ever from this
    2. no one has ever been shown to have problems because of this which should happen in motor skills etc if ‘it’s so bad’.
    3. I question the study – how did they get brain scans? did they gas people in a lab?
    4. never trust a half story

  2. Except for in real life, the exhaust fumes dissipate on the outside of your vehicle and is heavily diluted with mostly fresh air before it ever makes it to you cab interior if at all. Sort of irrelevant considering nobody sits in their cars breathing Diesel exhaust funes for 2 hours. And ya, duh, breathing in echaust fumes causes brain damage, no sh$t Sherlock. I was curious about this a few years back and drove around with an air quality tester for 2 weeks. Not much difference between sitting in my living room and driving down the highway at all.

  3. It appears that Canadian politicians and scientists have spent lifetimes sitting in traffic. That’s the only logical conclusion one can reach after seeing their policies and research results, anyway.

  4. Since people have been sitting in traffic worldwide for over a century and not being incapable of thought immediately thereafter I’d love to know who funded this study since it reads like yet another phony article designed to persuade us we all need to drive electric vehicles.

    1. On the contrary, I think it explains a lot about the level of brain function in advanced societies over the past century.

  5. This was quoted in DregsReport if you wondered why all these toxic denialist comments. I read Dregs to see what those on that spectrum are digesting and always wondered why he scavenges the so-called evil MSM, it is to get his minions to disclaim reality in comment sections. Clever rascals.

  6. so why are so many companies forcing people to go to work instead of doing the same work from home? greed and profits, but it’s killing us

  7. Someone tell the tree hugging libs to quit blocking highway traffic and the problem will be greatly reduced.

  8. Another bs article promoting EV toy cars that pollute more than any other form of transportation

  9. Oh man, we are more than doomed. Reading the comments…where did the whole “EV” thing come from? Are the car brain people that damaged already to not even think that maybe just maybe they should not be driving at all! got legs? use them! Is your job/home/daycare/fave coffee shop /insert other BS reason to drive “forcing” you to drive? Change that!

    Infuriating that car-brains think it’s fine to gas everyone around them. Stop shitting where you eat!

  10. I guarantee you two minute marijuana will incapacitate your brain more than 2 hour traffic. And the Damage will probably be more permanent.

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