According to a new study, tens of thousands of people died prematurely in California between 2008 and 2018 due to wildfire smoke.

According to a study conducted by researchers at UCLA and published in Science Advances, fine particulate matter (known as PM2.5) from wildfires resulted in 52,500 to 55,700 deaths and caused economic damages of $432 to $456 billion.

“The large and increasing impacts of wildfires on air pollution, as well as the death toll and economic burdens presented here, raise questions about societal investment in wildfire prevention and control,” the study says.

The study estimates that 2,305 people died from wildfire smoke in Sonoma County between 2008 and 2018. The study also estimated that there were 2,231 deaths in Santa Clara County, 2,063 deaths in Contra Costa County and 2,057 deaths in Alameda County.

Dr. Thomas Dailey, a pulmonary and critical care physician at Kaiser Permanente's Santa Clara Medical Center, said particulate matter is created by the combustion of solid materials, such as wildfires or cigarette smoke.

“The problem with particles this small – 40 of them can fit over the length of a human hair – is that not only do they lodge in the lungs and cause irritation, but they can also cause respiratory problems in asthmatics, emphysema/COPD patients, and young children with developing lungs, but they can actually be inhaled and absorbed into the bloodstream,” said Dr. Dailey. “Statistically, we're seeing an increase in heart attacks and strokes (from air pollution) in our emergency rooms. So these are very irritating, very small particles that can cause damage anywhere in the body.”

Dr. Dailey recommended wearing an N95 mask on days with poor air quality, but warned that it would not fully protect anyone from fine particulate matter.

“N95 masks protect against 95% of the fine particulate matter that comes in when you breathe. It's important to know that that's not 100%. N95 masks are designed for firefighters who are exposed to smoke because they have to be exposed to that. For first responders… They're not designed for someone to say, 'Oh, the air quality is bad. I'm going to put on my N95 mask and go for a jog today.' You're still exposing yourself to 5% of the fine particulate matter,” Dr. Dailey said. “If 'unhealthy air' means smoking a pack of cigarettes a day, then 'unhealthy for sensitive groups' is smoking three-quarters of a pack. 'Moderate' air pollution is smoking half a pack of cigarettes a day. There's no such thing as healthy air pollution.”

Dr. Dailey also urged residents to ensure that their homes are not exposed to outside air, as this could allow polluted air into their homes.

“When you smell smoke, you're breathing in particles,” he said. “This is going to happen again and again and we really need to prepare for it as a society. We're seeing how climate change is affecting us and one of the impacts is more and more wildfires. We've also seen that the smoke can travel hundreds of miles – if not further, even if you're not in close proximity to the fires.”