Children born in 2020 are projected to experience double the number of wildfires over their lifetimes compared to those born in 1960, according to recent studies. In regions like California, wildfires have become a common occurrence during the summer and fall seasons, releasing harmful particulate matter (PM₂.₅) into the air that poses significant health risks.
Wildfire-produced PM₂.₅ can penetrate deep into the lungs, causing immediate respiratory issues. While short-term exposure is linked to acute health problems like asthma, the long-term effects of repeated exposure are still unclear. A major challenge is accurately measuring wildfire-related PM₂.₅ exposure, as the intensity of pollution can vary drastically from day to day.
Current methods of measuring annual average PM₂.₅, which typically come from sources like power plants and vehicles, may not capture the sporadic yet intense nature of wildfire pollution. A person’s exposure to PM₂.₅ could be a steady low level throughout the year or a single, massive spike on a wildfire day, with both scenarios producing the same average but vastly different health impacts.
In 2022, the U.S. experienced an average PM₂.₅ exposure of 7.8 micrograms per cubic meter, with wildfires adding only about 0.69 micrograms annually in 35 states. However, this average can be misleading. During California’s 2018 Camp Fire, a nearby area saw PM₂.₅ levels spike to a record 310 micrograms in a single day.
New research from environmental scientists has introduced a framework that measures wildfire PM₂.₅ exposure based on frequency, duration, and intensity. These metrics better account for extreme pollution spikes and help researchers study the long-term health effects of wildfire exposure.
The study also highlights environmental injustices, revealing that Native American communities are disproportionately affected by wildfire pollution, experiencing nearly 1.7 times more PM₂.₅ exposure than the state average. This disparity is partly due to higher wildfire risks in rural tribal lands, often exacerbated by decades of poor forest management and restrictions on cultural burning practices.
As climate change intensifies wildfire frequency and severity, understanding the health impacts of repeated wildfire exposure is crucial for addressing health disparities and protecting vulnerable populations.