Harmful smoke from West Coast wild fires reached New York City this week. Getty Images
  • Multiple wildfires are burning on the West Coast of the U.S., leading to hazardous air quality.
  • Poor air quality is associated with a variety of health issues including exacerbated asthma and heart attacks.
  • The smoke from the wildfires has drifted over much of the U.S., potentially affecting air quality as far as Washington, D.C.

There are dozens of active wildfires burning in the West right now, some of which are the largest and lengthiest the region has seen in years.

The Beachie Creek Fire in Oregon and the August Complex Fire in Northern California are the largest of the fires and have been raging for weeks on end.

Washington state has a number of fires blazing, and the Bobcat and El Dorado fires are ripping through Los Angeles’s mountains. 

As plumes of smoke spill out of these fires, air quality in the West has plummeted.

Some areas, like San Francisco and Portland, are seeing record-breaking pollution levels.

All that smoke and haze has started to move east and affect skies as far as Indiana, Boston, and even Philadelphia.

Dr. Joel Kaufman, a professor of environmental & occupational health sciences, medicine, and epidemiology at the University of Washington, says this year is already shaping up to be one of the worst wildfire seasons we’ve seen.

“This year is going to be one of the worst if not the worst on record and we’re still fairly early in the fire season,” Kaufman told Healthline.

It’s impossible to know when exactly wildfires will die down, but experts suspect it could be weeks, if not months.

“There’s going to be a potential for them until it rains, which doesn’t happen until maybe December. Until that happens, we’re going to be in wildfire season,” says Dr. Mary Prunicki, the director of Air Pollution and Health Research at the Sean N. Parker Center for Allergy and Asthma Research at Stanford. 

What makes wildfire smoke dangerous?

When we talk about air quality, we often refer to a measurement called PM2.5, which tells us how many particles sized 2.5 microns and smaller are floating in the air.

When you look at a dark plume of smoke shooting out of a fire, you are seeing really tiny particles that can stay suspended in the air and not fall to the ground, says Colleen Reid, PhD, an assistant professor of geography at the University of Colorado Boulder.

As wind patterns change and the smoke gets pulled elsewhere, so do the tiny particles. 

“The reason we’re concerned about these really small particles is not only are they the ones that stay suspended in air but they’re also the ones that can get deeper into the lungs and cause more systemic health effects,” says Reid.

Reid, who studies air pollution, says the higher the PM2.5 levels, the greater the health effects. 

Thick smoke from multiple wild fires on the West Coast could be seen from satellites in space. Getty Images

What are the short-term health effects?

Most of the research we have on wildfire smoke inhalation and our health has looked at the short-term acute risk — or what happens to people’s health in the days after a wildfire hits. 

Anyone immediately exposed to high PM2.5 levels will feel it pretty immediately — there are the itchy eyes, sore throat, dry cough. 

Those particles can irritate the lungs and exasperate any preexisting lung conditions. 

There’s evidence that people with asthma refill their prescriptions more when there’s a wildfire nearby, according to Reid.

Research has found that during active wildfires there’s an 8 percent increase in asthma hospitalizations. A recent study from Canada identified a spike in ambulance calls for heart attacks, strokes, asthma, and other respiratory problems within an hour after PM2.5 increased.

When the air quality sinks, visits to the emergency room for respiratory problems increase, says Reid. 

One report found that there’s recently been an uptick in out-of-hospital cardiac deaths due to wildfire smoke exposure. The heart just stops and people aren’t able to make it to the hospital in time, says Prunicki. 

According to Reid, there’s a lot of good evidence showing that particles get into the lung and cause inflammation and oxidative stress.

“If there’s enough of those processes in lungs it can spill over and cause systemic inflammation and oxidative stress spills into other organs in the body,” says Reid. 

Prunicki’s past research found that teenagers who lived within 60 miles of a wildfire had systemic increases in inflammatory markers in their blood. 

Exposure to air also damages the immune system and it becomes harder to fight viruses and harmful bacteria.

A study from Montana found that communities that experienced wildfire smoke had higher rates of influenza during the next flu season. 

Some studies suggest smoky air can tax the cardiovascular system, too, though the findings have been somewhat mixed.

“You’re going to see increases in heart attacks, arrhythmia, neurologically you’re going to see an increase in strokes — that can happen within a few days of the wildfire smoke exposure,” Prunicki said, adding the risk is higher in people over 65 with preexisting conditions. 

Firefighters are still battling numerous wildfires in California and other western states. Getty Images

What about the long-term impact?

The long-term effects of wildfire smoke inhalation haven’t been studied as thoroughly, mainly because wildfires usually get contained more quickly, but Prunicki says “we know it definitely has long-term impact.” 

Based on long-term data on fossil fuel pollution, Kaufman expects heavy smoke could ultimately lead to higher rates of cardiovascular issues, pulmonary problems, and a greater risk of diabetes and dementia. 

“We have every reason to believe that if people have these exposures it’s going to set up inflammation in lungs and the airways and carry on for weeks and months even after the exposure is gone and set people up to have their asthma stay worse, to have maybe more risk of acquiring infectious diseases, or having worst cases of infectious diseases,” Kaufman said. 

Still, more research is needed to fill in the gaps about what happens after weeks and months of living in hazardous air. 

The fires hurt our mental health, too

“The stress of the pandemic plus the stress of this high air pollution, both from a mental health perspective as well as a physical health perspective, is a lot,” says Reid. 

The outdoors have been an escape for many people during the pandemic, especially in the West. When the air quality is as bad as it is, outdoor activities are taken off the table. 

“We know pretty clearly that these smoky days lead to depression and anxiety and can worsen those conditions in people who have them and can cause a lot of people to have symptoms of the blues,” says Kaufman. 

In previous wildfire smoke events, that’s the biggest impact people report, according to Kaufman.

There’s also some proof air pollution can impact our brain and cognition. 

Kaufman says evolving data suggests that wildfire smoke and air pollution can directly impact brain functioning.

Can the fires impact my risk of COVID-19?

Short answer: yes. 

Reid says we know wildfire smoke and air pollution in general makes someone more susceptible to respiratory infections. 

PM2.5 can also diminish our immune system’s ability to fight off infections like COVID-19. 

A new report found that air pollution is linked with a 9 percent increase in COVID-19 mortality. 

People who’ve recently recovered from COVID-19 or are now battling it will likely feel the effects of the smoke more.

“We know COVID can do quite a bit of damage to the lungs and therefore someone who maybe has already recovered, but they still have that damage in their lungs could be more affected by air pollution more so than they would have otherwise,” Reid said, noting there’s little concrete research on the link between the two thus far.

Airplanes and helicopters are used to stop wildfires from spreading. Getty Images

Here’s how you can protect yourself

The best thing to do if there’s a wildfire nearby with clouded, smoky air is to stay indoors with the windows closed. 

Not all buildings are well-sealed. Reid’s colleagues have found that rental units, especially older buildings, tend to be leakier, bringing in air pollution from the outside. 

Newer homes aren’t foolproof. Every time you open the door, some polluted air can sneak in. After days of that, a haze can build inside. 

Reid recommends purchasing a HEPA filter to clean the air inside your home. They can be expensive, so consider buying a smaller one that can clean the air in the room you spend the most time in. 

Some people have created their own air filters with a MERV-13 filter and box fan. While there’s less evidence on their effectiveness, Reid says they may be able to help. 

If you have air conditioning, set it to recirculate so it just cools the air that’s already inside instead of bringing new air in. 

Check your AC’s filter regularly — it can get clogged quickly in smoggy and smoky air conditions. 

If you’re in an older building, consider sealing off the windows and doors via weather stripping to make your house tighter. 

Lastly, look at the forecast and try to get some outside time in if and when the air quality improves. 

The green or yellow categories, which have a PM2.5 between 0-100, indicate a good time to be outdoors. The 100-150 PM2.5 range can be dangerous for people with underlying health conditions like asthma, heart disease, or COPD. Above 150, it’s unhealthy for everyone, so it’s best to curtail all outside activity. 

“People want to think twice about spending much time outside depending on their own health and own needs,” Kaufman said. 

If you do have to go out, wear a mask. Some masks — like an N95 or N99 — are better than others, but any mask is better than nothing. 

Lastly, listen to your body. 

If you’re coughing, limit your time outside even if the air quality index seems OK. 

Kaufman says the most important step, above all, is to get to a cleaner air environment. 

The bottom line 

There are dozens of active wildfires burning in the West right now, some of which are the largest and lengthiest the region has seen in years. As plumes of smoke spill out of these fires, air quality in the West has plummeted.

The haze from the wildfires has even reached the East Coast, potentially worsening air quality.

Smoky air can have drastic respiratory and cardiac effects; it can also tax people’s mental health. To protect yourself, limit outdoors time when the air is smokier, and filter inside air to the best of your ability. 

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