Major Link Found Between Air Pollution and Neurological Disorders

woman wearing a mask walking in a polluted city

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Key Takeaways

  • Both prolonged and short-term exposure to air pollution can have an impact on many chronic health conditions.
  • Recent data suggest a major connection between air pollution and neurological disorders.

There has been ample research done on the connections between human health and the natural world.  A recent study published in The Lancet Planetary Health focused on the ways that air pollution has the potential to negatively impact and exacerbate neurological disorders. 

This study focused on the ways in which PM 2.5 pollutants affect the brain, largely due to the microparticles reducing our defenses. Shaheen E. Lakhan, MD, PhD, FAAN, Executive Director of Global Neuroscience Initiative Foundation, says, "It is rapidly becoming more evident that our environment plays a large role in our brain health and wellness. Pollutants and toxins around us contribute to inflammation in and around the brain. They reduce our ability to fight off infections or inflammation and make us more susceptible to brain degeneration." 

What are the potential health effects of air pollution?

There are many potential negative health repercussions to air pollution exposure, both for long and short periods of time. The side effects can range from acute to chronic, and they have the potential to affect adults, children, and pregnancies.

Environmental journalist and author of Choked: Life and Breath in the Age of Air Pollution Beth Gardiner says, “When air pollution in a place goes up, heart attacks go up, strokes go up, cancer, premature births, stillbirths, childhood leukemia...the list goes on and on."

Researchers analyzed data from Medicare recipients who were admitted to the hospital between 2000 and 2016. Data showed that there was a mostly linear connection between increases in PM 2.5 and the hospital admissions for Parkinson’s, Alzheimer’s, and other dementias. This is likely due to the ways in which pollution increases oxidative stress and neurodegeneration.

Shaheen E. Lakhan, MD, PhD

Pollutants and toxins around us contribute to inflammation in and around the brain. They reduce our ability to fight off infections or inflammation and make us more susceptible to brain degeneration.

— Shaheen E. Lakhan, MD, PhD

Noelle Eckley Selin, atmospheric chemist and author of Mercury Stories, says, “One of the things we’ve known for a long time about PM 2.5 is that it has health impacts. There’s a mountain of evidence on how PM 2.5 can have cardiovascular and respiratory impacts on populations—all potentially linked to premature mortalities."

Selin is also Director of MIT's Technology and Policy Program and a faculty member of both the Institute of Data, Systems, and Society and the Department of Earth, Atmospheric, and Planetary Sciences. She confirms that the factor setting these particles apart from others is the size, and that is what enables PM 2.5's ability to do so much damage. She goes on to discuss how this study provides a novel take on the PM 2.5 and how this data just adds to the already overwhelming evidence that this type of air pollution needs to be regulated for the health of communities. 

What is PM2.5?

PM 2.5 is a pollutant classification that the Environmental Protection Agency defines as, "fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller."

Particles in the air and atmosphere vary in size, and they can involve a range of chemical compositions. PM 2.5, also known as fine inhalable particles, is another name for microparticles that have the ability to be inhaled and absorbed deeply into your lungs. Selin says, “PM 2.5 is an umbrella term for all of the really tiny particles in the atmosphere, and it’s called 2.5 because they are smaller than 2.5 microns in size.”

What Causes Air Pollution?

Even though scientists and environmental activists have discussed the importance of lowering emissions for the sake of our overall health, the extent air pollution's potential impact on our bodies long term can be alarming.

Gardiner says, “It’s sort of invisible in that no one is said to have died of air pollution… we don’t see it happen, but it’s driving up the death rates of all sorts of things. The variety of the impacts is something that shocked me [in my research].” 

She touches on the importance of recognizing environmental racism, noting higher levels of pollution in areas that are predominately Black. Some examples of this are the infamous Cancer Alley in Louisiana and the ongoing Flint Michigan water crisis. There are also links between air pollution and diabetes and obesity, which both have high prevalence in the Black community. 

What contributes to air pollution?

Gardiner says that fundamentally, air pollution is caused by these few things:

Transportation. That’s traffic, cars, buses—all using diesel or gasoline. Any time you burn something, you create exhaust, and it stays in the air and you breathe it in.
Electricity and power plants. The United States uses coal in some areas but has made a shift to natural gas. It’s a little cleaner burning but still creates a lot of emissions.
Industry. These are your major factories and plants.

Noelle Eckley Selin, PhD

There’s a mountain of evidence on how PM 2.5 can have cardiovascular and respiratory impacts on populations—all potentially linked to premature mortalities.

— Noelle Eckley Selin, PhD

There are standards that aim to regulate emissions from companies, but this does not eradicate the impacts of air pollution. Selin says, “Even some of the levels [of air pollution] that are below the current standards in the United States still have impacts. The more they can be reduced, the better, and the major source is fossil fuels.” Gardiner believes that in order for the levels of air pollution to monumentally shift, strict regulations have to be placed on companies, as they are the primary producers of toxic emissions.

Scientists and researchers hope that alongside regulations, additional data from studies like these will inspire changes in healthcare procedures overall. "For our brain’s sake, the findings of such research should inform public policy including health, environmental, and safety standards." says Lakhan.

What This Means For You

When it comes to treatment and prevention of dementia-related disorders, medical providers and researchers can take this information into account when it comes to a treatment plan. Additionally, knowing the direct connections between air pollution and neurological disorders can enable individuals to make informed choices when making decisions about city and housing locations.

8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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