Is Breathing Wildfire Smoke As Bad As Smoking Cigarettes?

As wildfires blaze through Canada, sending smoke to the Midwest and East Coast, you might experience respiratory symptoms — even if you consider yourself a healthy person without any lung or heart conditions.

The air quality index, or AQI, tells you how clean or polluted the air is in your city, and according to the New York State Department of Environmental Conservation, the higher the AQI, the greater the health concerns. Generally, once the AQI reaches 100, air pollution is “moderate” or “unhealthy for sensitive individuals.” Up to 200, this changes to “unhealthy” and “very unhealthy.”

Many people are quick to compare bad air quality to smoking, which is another known trigger for respiratory issues. And it’s a valid analogy, backed by science.

A 2020 study by the Stanford Woods Institute for the Environment found that breathing in smoke from wildfires that raises the AQI to 150 for several days is equivalent to smoking seven cigarettes a day. (By comparison, the AQI in New York City on Wednesday because of the Canadian wildfires was more than 300.)

That’s if you’re standing outside the whole time the AQI is 150, according to the study. But, the researchers noted, some of that pollution can seep indoors. And short-term exposure to high levels of wildfire smoke was found to be similar to chronic exposure to low levels of air pollution.

Dr. Afif El-Hasan, a volunteer medical spokesperson for the American Lung Association, told HuffPost that comparing cigarette and wildfire smoke is appropriate. It goes back to how small pollutant particles are, which can contain dust, soot, dirt, smoke, liquids and chemicals ― all of which make their way into our bloodstream. These particles can cause inflammation, affecting our lungs and other parts of our bodies as well.

“You’re basically dealing with the inhaling of vegetation, like tobacco leaves in the cigarette, so it’s true,” El-Hasan said. “Because you’re burning an organic substance, both of them have many different chemicals that are being given off. Some of them irritate the lungs immediately, and some are carcinogens.”

Breathing in smoke can affect you immediately, which is why you experience symptoms including coughing, trouble breathing, asthma attacks, stinging eyes, scratchy throats, runny nose, headaches and chest pain.

“I believe the comparison between the effects of wildfire smoke and cigarette smoke on the lungs is reasonable,” Brady Scott, a fellow of the American Association for Respiratory Care, told HuffPost. “While the specific types and quantities of toxins in wildfire smoke are still being studied, we know that inhaling smoke can harm our lungs and overall health. Although wildfire smoke and cigarette smoke may not be identical, the comparison emphasizes that breathing in wildfire smoke can be harmful.”

“You walk into a room where everyone is smoking, you’re going to start coughing right away,” El-Hasan added. “It’s the same with this.”

The long-term effects of each are also similar, especially for sensitive groups. Since smoking damages blood vessels and makes them thicker and narrower, blood clots can form and increase the risk of a stroke, as clots block blood flow to the brain. Similarly, wildfire smoke increases the risk of stroke by 40% in people over the age of 65 and the rate of heart attacks.

However, other factors might also apply, El-Hasan said. “You also have to think about how long the person is out there, are they actively breathing, and what kind of smoke are we dealing with.”

Wildfire smoke is a combination of water vapor, pollutants including carbon monoxide, and particle pollution made up of acids, chemicals, soot, metals, dust, pollen and mold. All the air we breathe contains particle pollution. But it’s these particles’ ability to enter our lungs, especially at high concentrations, that makes inhalation harmful.

“It’s important to note that even individuals without pre-existing lung conditions can experience adverse effects from poor air quality,” Scott said. “When exposed to polluted air, a person’s airways can become irritated, resulting in coughing, shortness of breath and wheezing. For individuals already dealing with asthma or other lung diseases, this can further worsen symptoms.”

Wildfires usually consist of fine particles, which make up 90% of the pollutants in wildfire smoke. These pollution particles are small, allowing them to easily pass through the nose and throat into the lungs, then into the bloodstream.

“Wildfires are unique in several ways,” El-Hasan said. “First of all, what burns in that forest is different in each area. Some of it is man-made. You’re dealing with ash from trees and vegetation, but you could also be dealing with chemicals like plastics.”

Generally, inhaling plastic fumes from wildfires can increase the risk of heart disease and increase respiratory side effects such as asthma, skin irritation, headaches, and nervous and organ system damage.

Similarly, cigarette smoke, specifically tobacco smoke particles and second-hand smoke particles, are small enough to travel through the lungs and be absorbed quickly into the bloodstream.

Fine particles that make their way into your lungs can cause persistent coughing, phlegm, wheezing and difficulty breathing. Additionally, particle pollution from wildfires might make it more difficult for your body to remove foreign materials such as viruses and bacteria.

Short-term exposure will still contribute to respiratory symptoms and effects, including bronchitis, reduced lung function, increased risk of asthma and increased risk of emergency room visits and hospitalizations.

“The lungs will heal themselves by getting rid of the particles one way or the other. Ultimately, the ash that you inhale is filtered in the upper airway, or lungs,” El-Hasan said. “The chemicals that get into the body through the lungs to the bloodstream will hopefully be neutralized at some point through the liver.”

However, being able to filter out and resolve the reaction you have to smoke might be harder if you’re part of a sensitive group. This includes people with asthma and other respiratory diseases, people with cardiovascular disease, children under 18, pregnant women, older adults, people in low-income and marginalized communities, and outdoor workers.

Similarly, both cigarette and wildfire smoke can stay in the lungs and air for a prolonged time. Wildfire smoke can linger for days, El-Hasan said. “Even when the wildfires are out, there’s still particles being sent to us. There’s still ash, gases, excreted from those parts that were burning.”

Even if the air is clearing up, it’s important to check the air quality in your city and take the proper steps to protect yourself.

Limiting your exposure is the best thing you can do. However, this can be difficult for people who work outdoors or experience exposure inequalities.

Prevention options for people who are more likely to be exposed to smoke ― such as people living in older homes with less ineffective indoor air filters ― include wearing N95 masks and using electric HEPA air filters in one room at a time.

“Try to stay indoors, make sure you have an air filter if you can, but also, if you’re someone who has a chronic lung disease or heart disease, make sure you’re taking your medicine, and that you have your medications available if there’s a problem,” El-Hasan said. “This is not the time you want to go ‘my inhaler is not working.’”

The original version of this story was published on HuffPost at an earlier date.