rewrite this title Your Questions About Wildfire Smoke and Health, Answered

Several fires continued to ravage the Los Angeles region on Thursday, killing at least five people and forcing thousands to flee their homes. Firefighters are still struggling to control the blazes, which have led to wildfire smoke that’s worsening the air quality in the region.

Wildfire smoke can travel long distances and affect the air quality far beyond the immediate vicinity of the fire. In 2023, smoke from wildfires in Canada spread along the eastern coast of the U.S. and beyond, prompting officials to issue air quality warnings in places including New York, North Carolina, and Ohio.

TIME spoke to experts about the dangers of wildfire smoke and how LA-area residents can best protect themselves.

Read More: How to Help Victims of the Los Angeles Wildfires

How does wildfire smoke affect your lungs?

Wildfire smoke contains many pollutants, including tiny particles that can get into your lungs and even your bloodstream, says Sara Adar, a professor of epidemiology and global public health at the University of Michigan School of Public Health. 

Inhaling wildfire smoke can lead to symptoms like difficulty breathing, shortness of breath, and coughing, says Dr. MeiLan Han, a spokesperson for the American Lung Association and professor of medicine and chief of the Division of Pulmonary and Critical Care at University of Michigan Medicine. Wildfire smoke can also lead to other symptoms, such as a burning or stinging sensation in your eyes and a scratchy throat.

Can you ‘flush’ smoke out of your body?

Your body is able to break down some of the harmful smoke particles, and you may cough some of it out, but Han says there’s no safe way to intentionally “flush” the smoke out of your body. Some of the particles may never get broken down.

Who is most at risk?

While anyone can feel the effects of wildfire smoke, there are certain groups of people who are most at risk, such as children, older people, people who are pregnant, and people with chronic health conditions, particularly cardiac or respiratory conditions. Breathing in wildfire smoke can trigger flare-ups for people with chronic lung conditions, could lead to asthma attacks, and could even increase the risk of heart attacks and strokes for vulnerable populations, Han says.

How long does it take to recover from wildfire smoke?

It can vary from person to person, depending on what, if any, pre-existing health conditions they may have. For many people who are healthy and don’t have underlying health conditions, the short-term effects of wildfire smoke will likely resolve once they’re no longer exposed to the smoke, Han says. But for people most at risk, the effects of wildfire smoke could last longer—for instance, smoke exposure could trigger a flare-up of a chronic respiratory condition and the inflammation in that person’s lungs could be worse, so symptoms could last for a week or longer.

How can you protect yourself?

The best way to protect yourself against wildfire smoke is to stay inside with your doors and windows shut as much as possible to reduce your exposure, Han says. Adar also recommends running an air purifier, if you have one.

If you have to go outside, wear an N95 or KN95 mask. If you’re driving, make sure your car is recirculating the air rather than bringing in air from outside, Han says. And if you have any pre-existing health conditions, make sure you have all your medications on hand in case you experience any kind of adverse reaction to the wildfire smoke.

Does the air quality improve after it rains?

Rain can help clear the air and improve air quality. Even when there isn’t an active wildfire, if an area is experiencing a drought, there can be more dust particles in the air that can contribute to increased air pollution and worsen air quality.

How long can you be outside when the air quality is unhealthy?

“It’s all kind of relative,” Han says. The effect of poor air quality varies from person to person, and depends on how bad the air quality is. But Han says: “If you’re going to be outside for a reasonable amount of time, I would consider wearing a mask.”

Adar says researchers have not found evidence that there’s ever a safe level of exposure to the particles found in wildfire smoke. Both Adar and Han recommend that people check the Air Quality Index in their area to get up-to-date information.

What are the long-term effects of wildfire smoke on your body?

Research suggests that repeated exposure to air pollution, including wildfire smoke, can increase the risk of developing chronic respiratory conditions, Han says. Some studies suggest that wildfire smoke can also affect brain health; Adar and her colleagues studied the link between long-term exposure to air pollution and dementia in older adults in the U.S., and found that wildfire smoke was one source of air pollution that can have particularly harmful effects on the brain.

Read More: Wildfire Smoke Is a ‘Public Health Threat’ That Can Have Lasting Impacts, Experts Say

“Because of climate change, and the fact that we’re starting to see [wildfires] more and more, it’s becoming a very active area of research,” Han says of the long-term impacts of wildfire smoke exposure. “We need to think hard about how we can obviously try to prevent the wildfires, but [also] think about how we can protect air quality better moving forward, generally speaking, because it is becoming an increasing health concern—not just a one-off event.”