Wildfire smoke linked to heart, lung, and pregnancy risks

Exposure to the 2018 Camp Fire in California was linked to changes in cognition and brain activity six to 12 months later. Several studies have also connected longer-term exposure to higher dementia risks. California data show an increase in fungal infections in the months after exposure, likely from spores in the smoke.

Exposure levels and mitigation “There’s no safe level” of inhaled particles from wildfire smoke, said Doug Brugge, who chairs the Department of Public Health Sciences at the University of Connecticut School of Medicine. Any amount triggers inflammatory responses.

Children, the elderly, and people with chronic illnesses are most vulnerable. Even healthy adults can experience sore throats, excessive phlegm, coughing, headaches, and brain fog that appear immediately and last after the smoke clears, said Keith Bein of the Air Quality Research Center at the University of California, Davis.

Experts advise wearing N95 masks and limiting outdoor activities, especially strenuous exercise. The longer a person stays outside and the harder they breathe, the more pollution they inhale, said Dr. Jasvinder Singh, a lung medicine specialist at Medstar Franklin Square Medical Center in Baltimore.

Indoor air purifiers that trap particles smaller than 2.5 microns are also recommended. “Air purifiers reduce exposure and in our studies reduced blood pressure and cognitive impacts of air pollution,” Brugge said. UC Davis offers instructions for building a simple purifier for those who cannot buy one.

Indoor air quality Particulates from wildfire smoke enter most buildings in high concentrations. On average, indoor levels are about half of outdoor levels, Singh said. In poorly sealed buildings, concentrations can reach 70 percent of outdoor levels.

The EPA advises avoiding indoor activities that add more fine particles during smoke events, such as smoking, frying or broiling food, burning candles or incense, and vacuuming without a HEPA filter. Particles settle on clothes, walls, and surfaces and continue to be released into the air after the smoke plume passes.

frequent wildfires, likely linked to climate change, mean repeated exposure. The health effects over multiple seasons remain unclear. “It is hard to make predictions because it is hard to say how many fires people will be exposed to, how long the fires will burn, or what the smoke will contain,” Bein said.

Researchers are studying long-term effects on water supplies, crops, livestock, urban wildfire smoke, in-utero exposure, and whether smoke worsens the effects of extreme heat. Nutrients in the smoke may contribute to downwind algal blooms, affecting drinking water and lake ecology.