August 16, 2023 – People living in areas with high levels of fine particulate air pollution (PM2.5)—particularly emissions from agriculture and wildfires—face increased risk of dementia in their older years, according to a new study.
The study was the first to look at whether PM2.5 from different sources carries different risks for dementia, according to an August 14 article in STAT.
For the study, researchers conducted cognitive assessments on roughly 30,000 people who didn’t have dementia but who were exposed to different types of air pollution across the U.S. Analyzing participants’ exposure to PM2.5 between 1998 and 2016, they considered a range of emissions sources, including agriculture, traffic, energy use by industry, coal combustion, and wildfires. Emissions from agriculture and wildfires appeared to be more harmful to the brain, they found.
Marc Weisskopf, Cecil K. and Philip Drinker Professor of Environmental Epidemiology and Physiology at Harvard T.H. Chan School of Public Health, who was not involved with the study, told STAT that the study is a “great step forward” because it parses out which components of air pollution are most dangerous. He noted that the study could provide guidance for public health interventions during a time of marked increases in wildfires in the U.S. “If there are ways to keep people away from the smoke when it happens, then that would lessen the impact on dementia,” he said.
Air pollution may increase risk for dementia (Harvard Chan School release)