The Los Angeles wildfires have claimed the lives of at least 24 people and have burned well over more than 12,000 structures.
While the focus is understandably on avoiding the flames, another immediate danger lurks across the county and beyond, one more difficult to escape: smoke.
The most dangerous component of wildfire smoke is fine particle pollution, also known as PM2.5 or soot.
These tiny particles, smaller than one 20th the width of a human hair, can, if inhaled, become embedded in the bloodstream and lungs.
It is estimated that about one-third of all particulate matter pollution in the US now comes from wildfire smoke.
“Wildfire smoke is super toxic to the lungs, more so than ‘regular’ smoke, because of the concentrations of fine particulates,” said Don McKenzie, an assistant professor at the University of Washington’s School of Environmental and Forest Sciences.
“People with compromised lung function are at higher risk of harm,” he added.
“Damage from smoke exposure of any type is cumulative, but especially with the high concentrations of the fine particulates, because they can lodge themselves in small spaces within the lungs.”
Air pollution is estimated to kill about 100,000 people in the US each year.
A significant portion of these deaths come from inhaling smoke from the burning of fossil fuels, wood and other materials (including from wildfires) that release toxins into the air.
Wildfire smoke can be especially dangerous for certain populations, including those with pre-existing conditions like asthma and COPD, pregnant people, those who are low-income or unhoused who may not have access to indoor clean-air spaces, and very young children whose respiratory systems are still developing.
“While air quality index levels in LA have reached levels known to be hazardous for everyone, we’re particularly concerned about smoke exposures among a few groups who might be disproportionately exposed or more likely to experience health impacts as a result of wildfire smoke,” said Claire Schollaert, a postdoctoral scholar at the UCLA Fielding School of Public Health.
In 2023, New York City saw a dramatic rise in emergency room visits, many related to asthma attacks, when smoke blew into the city from Canadian wildfires. READ MORE
