As wildfires have ripped through Los Angeles in recent weeks, thousands of people have been displaced and more than two dozen are reported dead.
The consequences have been devastating, and research suggests that the dangers will continue for weeks to come. In particular, a significant body of research demonstrates that exposure to wildfire smoke has negative effects on the brain.
One study of more than 10,000 U.S. adults found that exposure to wildfire smoke impacted cognitive function in the hours following exposure and the next day. Data showed that there were greater effects on cognition for those exposed to more dense smoke and those inhaling smoke from wildfires in the western U.S. The latter was most likely due to the sources of the burning in western states, which can create more toxic smoke.
Another study of bushfires in Australia found that particulate matter from smoke leads to oxidative stress, a condition where unstable molecules in the body cause cell damage. This, in turn, triggers inflammation in the brain, reactions that increase the risks for impaired cognitive function, memory loss, and susceptibility to neurodegenerative diseases like Alzheimer’s and Parkinson’s disease.
A systematic review published last year pulls together a broad body of evidence to detail how exposure to extreme heat and smoke – both becoming more prevalent due to climate change – has lasting impacts on the body’s ability regulate its temperature; cognition in both the short- and long-term; and ultimately the risk of developing neurological disease.
The evidence is clear that exposure to wildfire smoke and extreme heat have negative effects on the brain. But what can we do about it?
Mark Lachs, chief of geriatric and palliative medicine at the Weill Cornell Medical College and co-director of the Cornell Institute for Research on Climate and Aging, has some evidence-based recommendations to stay safe during wildfires:
- Purchase an air purifier for your home.
- If there is wildfire smoke near your home, keep windows and doors shut.
- Avoid going outside if wildfire smoke is present.
- When you do go outside, avoid strenuous activities such as jogging or mowing the lawn, which increase your respiration rate.
- If you do need go outside when wildfire smoke is present, wear an N95 mask, which can filter out large particles in the air.
The take-home message: Clear evidence shows that exposure to wildfire smoke has negative consequences for the brain, affecting cognition and increasing the risk for neurological conditions such as Alzheimer’s disease and dementia. But if you are exposed to wildfire smoke, there are steps you can take to reduce the risk of neurological problems.