Fine Particle Exposure Linked To Brain Damage In Older Adults

BY ON April 27, 2015

Image of smoke coming out of smokestack shaped like brain

This was written by Amanda Peterka for E&E News

A study of older adults has found that long-term exposure to air pollution is associated with brain damage and a type of “silent” stroke.

The study led by researchers from the Beth Israel Deaconess Medical Center and Boston University School of Medicine examined more than 900 people at least 60 years or older. They found that participants who were exposed to higher levels of fine particulate matter had brains that were more likely to show signs of aging and a type of silent stroke that results from blockages in the blood vessels supplying their brains.

The authors said the results were concerning. Silent strokes increase the risk of overt strokes, dementia and depression, among other negative health effects.

“This is one of the first studies to look at the relationship between ambient air pollution and brain structure,” Elissa Wilker, a researcher in the Cardiovascular Epidemiology Research Unit at Beth Israel Deaconess Medical Center, said in a statement. “Our findings suggest that air pollution is associated with insidious effects on structural brain aging, even in dementia- and stroke-free individuals.”

The study was first published online yesterday and will appear in the May print issue of the journal Stroke. It was funded by grants from the National Institutes of Health and U.S. EPA.

The study’s 900 participants, all of whom were free of dementia and stroke, lived in the New England region and were part of the Framingham Heart Study, a long-term project of the National Heart, Lung and Blood Institute that seeks to identify the causes of cardiovascular disease. They were examined as part of the heart study in the 1998-2001 time frame.

In the study, the authors analyzed exposures to fine particulate matter, or particles that are one-thirtieth the width of a human hair. They measured how far the participants lived from major roadways — cars and trucks are a major source of fine particles — and used satellite imagery to assess exposure.

According to the results, an increase of 2 micrograms per cubic meter of fine particle pollution was associated with smaller brain volume. The results meant that people living in more highly polluted areas had the brain volume of someone a year older.

On average, participants exposed to pollution levels commonly observed in major cities in the United States had a 46 percent higher risk of silent stroke than those living in less polluted areas.

“These results are an important step in helping us learn what is going on in the brain,” Wilker said. “The mechanisms through which air pollution may affect brain aging remain unclear, but systemic inflammation resulting from the deposit of fine particles in the lungs is likely important.”

The researchers are planning further study on the impacts of air pollution on brain shrinkage, stroke and dementia.


TOPICS: Air Pollution, Pollution

  • Marcia G. Yerman

    Watch out! James Inhofe might claim this as an excuse!

  • VicSteblin

    I went through honors math with all those proofs etc, and after 35 years in a smokey place, I am stupid now. QED

  • Wood Smoke is comprised of 80 to 90% Fine Particulate Matter

  • Two other studies published in 2015 also report effects of PM2.5 pollution on the brain:
    1) Increased exposure of just 1 ug/m3 PM2.5 increased the risk of dementia by 8%, Alzheimer’s by 15% and the risk of Parkinson’s diseases by 8%;
    2) Increased PM2.5 exposure of 3.5 ug/m3 reduced the volume of white matter in the brain by 6.2 cubic centimeters.

    In December 2014, research linking PM2.5 to autism was published. Prof Frank Kelly, director of the environmental research group at King’s College London, discussed the findings: “I think if it was this study by itself I wouldn’t take much notice, but it’s now the fifth that has come to the same conclusion”.

    Many people do not realize that wood stoves are the main source of PM2.5 in local neighborhoods and that switching to non-polluting heating would save many brains and lives.

    Exposure to toxic chemicals known as PAH (the main toxins in woodsmoke) during pregnancy and early childhood have also been found to cause genetic damage in babies (based on tests of umbilical cord blood) as well as reduced IQ when children start school and increased risk of behavioral problems such as anxiety and attention deficit.

    For more information and links to the research papers see woodsmoke .3sc .net/health andwoodsmoke .3sc .net/pah

    • Vince Vespa

      Amen, Bill Lewin! New England’s dirtiest secret is how filthy all that wood burning makes the air at human breathing level, where it counts. Vaunted monitor readings be damned if your neighborhood is a localized hot spot contaminated with wood smoke.