Summary
Wildfire smoke, motor vehicles and factories all emit a type of air pollution called fine particulate matter (PM2.5) This is a microscopic mixture of solid and liquid droplets in the air that are 30 times smaller than the width of an average human hair. High levels of PM2. 5 also have been shown to raise the risk of heart disease, asthma and low birth weight.
Researchers used air quality monitoring data, satellite imagery and machine learning. They determined each study participant's exposure to both sources of PM2.5. They compared that information to subsequent diagnoses of dementia in participants' health records.
An Air Quality Index (AQI) number of 100 or higher means the air is unhealthy to breathe. People should stay inside when possible and close the windows.
