More Evidence Links Wood Smoke Pollution to Dementia

An alarming new study has added even more reason to be concerned about wood smoke.

For some time, evidence has been mounting that fine particle pollution is linked to increased risk of dementia. This latest study, which was published in Science, has made this connection even more conclusive.

Wood burning is one of the largest sources of fine particle pollution.

According to coverage in The Guardian, researchers found that exposure to fine particle pollution causes proteins in the brain to misfold into the “toxic clumps” that appear in people with Lewy body dementia.

Lewy body dementia, or LBD, is a serious degenerative neurological disorder. Abnormal clumps of protein, which are known as Lewy bodies, build up in regions of the brain that affect thinking, memory, and movement. 

People with LBD experience memory loss, confusion, hallucinations, intense sleepiness, and other cognitive symptoms that get worse over time, as well as muscle rigidity, difficulty moving, and tremors.

In the latest study, researchers analyzed the hospital records of over 56 million Medicare patients over a 14 year period. They found that those who were hospitalized for the first time with Lewy body dementia lived in areas with higher levels of PM_2.5 (fine particle pollution). 

To further confirm this link, the research team also conducted studies with mice. According to The Guardian, “the results were striking.” Normal mice that were exposed to PM_2.5 every other day for 10 months had nerve cells die off, leading to brain shrinkage and cognitive decline. Further mouse studies showed that PM_2.5 “drove the formation of aggressive, resilient and toxic clumps” of the protein that resembles Lewy bodies in people.

This latest study adds to countless previous studies that have linked PM_2.5 exposure to dementia. One previous study looked specifically at the effects of PM_2.5 from wood burning and found that people who live in neighborhoods where more people heat with wood are more likely to develop dementia.

At this point, many leading researchers believe the evidence is conclusive. Caleb Finch, the leader of USC’s Air Pollution and Brain Disease Research Network stated, “I have no hesitation whatsoever to say that air pollution causes dementia.”

The science is clear: If you or your neighbors burn wood, you are at increased risk of developing dementia.