Wildfire Smoke Pollution Travels Thousands of Miles - Dr. Axe

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Wildfire Smoke Inhalation: Here’s What It Does to Your Body


Wildfire smoke - Dr. Axe

Over the summer, we faced disastrous Amazon fires in Brazil, and this week we’re grappling with the news of another major bout of wildfires in California. The newest reports show that more than 300 blazes have broken out in California — and the National Weather Service issued an “extreme” red flag warning for Los Angeles and Ventura counties.

Beyond the ecological consequences of such serious situations, we’re also left with concerns about air pollution and how it may impact the health of all of us. California residents are smelling smoke 50+ miles away from the blazes. Urged to stay indoors, health officials advise wearing respirator masks to avoid smoke and ash exposure outside.

According to AirNow, several California cities are dealing with “hazardous,” “very unhealthy” and “unhealthy” air quality levels. AQIs (air quality index levels based on air pollution) above 100 are indicative of moderate pollution in the air; the most impacted cities in Cali are currently facing AQIs around 300.

We know that these wildfires, in addition to those from years past, will add to air pollution and cause harm to people across the country.

After the deadly wildfire in California last year, many parts of the state experienced poor air quality advisories. Residents of these areas no doubt face a number of health ailments as a result of wildfire smoke inhalation, including asthma, headaches and burning eyes. And now residents in California are facing yet another wildfire battle.


Long-term impacts of wildfires are also a concern. And, on top of that, scientists are warning U.S. residents that the consequences of wildfire smoke inhalation can spread across the country, far from the actual site of the fire.

Did you know that wildfire smoke can travel thousands of miles? Reports indicate that smoke from the 2018 wildfires in California traveled 3,000 miles to the east coast of the United States. The smoke consisted of thousands of individual chemical compounds and created a haze that, when caught up in the atmosphere, could travel across the country.

But eventually, it settles, and that’s when it poses a health threat to residents, despite living so far away from the initial flames.

The recent wildfires in California and the consequences of smoke inhalation across the country are just another example of the health effects of climate change. Hot and dry conditions are vulnerable to severe wildfires, and the wildfire season continues to lengthen.

Not only is California facing very low humidity, which creates the potential for fires to spread very quickly, but the state is also experiencing high winds, with isolated gusts up to 80 miles per hour. This combination created historic fires burning in many parts of the state.

What we’ve learned from the constant threat of wildfires is that until the country, and world, makes bigger moves on addressing climate change, we need to help ourselves by preventing wildfire smoke inhalation and exposure to dangerous particles that loom large when the destruction is seemingly over.

What’s Causing All of These Wildfires?

According to the National Park Service, humans cause nearly 85 percent of wildland fires in the Unites States. The major human causes of wildfires include:

  • Leaving campfires unattended
  • Burning debris
  • Negligently discarding cigarettes
  • Intentionally starting a fire (acts of arson)

There are also two natural causes of wildfires — lava and lightening. (Interesting, climate change is fueling more lightening.) Usually, when lightening causes a fire, it’s from an unusually long-lasting, hot lightning bolt. These are factors that start a fire, but what role does the environment and the changing climate play in the intensity and frequency of deadly wildfires?

The spread of wildfires is also influenced by many environmental factors, including:

  • High temperatures
  • Drought
  • Temporary dry spells

Data shows that wildfires have become more problematic for public health and our ecosystems in the past decades because of climate change.

According to the Union of Concerned Scientists (UCS), higher spring and summer temperatures cause drier soils for a longer period of time, thereby increasing the likelihood of droughts and extending the wildfire season. This is particularly true in the western United States, where hot and dry conditions increase the intensity of wildfires once they are started.

The UCS reports that between 1986 and 2003, “wildfires occurred nearly four times as often, burned more than six times the land area, and lasted almost five times as long when compared to the period between 1970 and 1986.”

On top of that, the U.S. wildfire season is projected to lengthen, especially in the Southwest where the season is expected to go from seven months to all year long. The severity of wildfires is also expected to increase, as moist, forested areas become dried and hotter due to climate change. On top of that, as the climate continues to warm, lightning strikes will continue to cause an uptick in wildfires.

Not only is the increased threat of wildfires scary for people living on the west coast of the United States, it should also be concerning for people across the country and beyond. Research shows that air pollution travels and disburses around the world, even across entire oceans.

Air pollution is distributed by air patterns, wind cycles, precipitation and the transportation of food. And when it comes to particulate matter from wildfire smoke, it’s the wind that’s doing the work.


Winds lift the smoke up, bringing the extremely tiny particles with it, and carrying it across the United States. Then, the natural jet stream pulls smoke and particles down.

The same issue occurred with the amazon fires. The fires are causing a large increase in carbon monoxide in the atmosphere and the winds are pushing the pollution across the continent and downwards.

What Wildfire Smoke Does to Your Body

To understand what wildfire smoke inhalation does to your body, it’s helpful to know what’s exactly inside the smoke.

According to the Environmental Protection Agency, wildfire smoke is a combination of:

  • Water vapor
  • Carbon dioxide
  • Carbon monoxide
  • Nitrogen oxides
  • Hydrocarbons
  • Trace minerals
  • Particles
  • Several thousand other compounds

Several factors influence the composition of wildfire smoke, including the fuel type, wind conditions and temperature of the fire. When wood and vegetation serve as the fuel, the wildfire produces a slew of compounds, including cellulose, oils, waxes and starches. Depending on the type of wood or plants that are burning, the specific composition of wildfire smoke will vary.

Scientists call wildfire pollution “particulate matter.” This is what poses the biggest public health threat. These small particles from wildfires can travel thousands of miles in the air, and people within a 25-mile radius of the fire face serious health risks for up to two weeks after the fire is out.

And scientists just uncovered the link between air pollution and children’s mental health. Particulate matter seems to trigger more depression, anxiety and even suicidal tendencies in the days following poor air quality.

Particulate matter is a generic term for particles suspended in air as a mixture of liquid droplets and microscopic solid particles. And here’s the big danger of particulate matter: When we inhale, it may land in the deepest recesses of the lungs.

Wildfire smoke also spreads other dangerous pollutants, including carbon monoxide, formaldehyde, benzene and acrolein. In fact, the 2019 Amazon fires emitted a whole lot of carbon monoxide into the air. NASA released a report that CO from the fires were clearly detectable by satellites and it drifted southeast into Brazil and other parts of South America.

That may seem too far away to concern U.S. air quality, but NASA reports that CO is a pollutant that can travel long distances and strong winds can carry it downward to where it can significantly impact air quality.

According to the EPA, the effects of smoke inhalation range from eye and respiratory tract irritation, to more serious disorders affecting the lungs and heart. The more common (and somewhat milder) symptoms of wildfire smoke inhalation and exposure to particulate matter post-fire include:

  • Trouble breathing
  • Wheezing
  • Asthma attacks
  • Persistent cough
  • Buildup of phlegm
  • Bronchitis
  • Chest pain
  • Rapid heartbeat
  • Headaches
  • Runny nose
  • Sore throat
  • Skin and eye irritation
  • Fatigue

More serious health effects of smoke and particle exposure include:

  • Reduced lung function and lung disease
  • Pulmonary inflammation
  • Reduced immune function
  • Aggravation of pre-existing respiratory and cardiovascular disease
  • Premature death

On top of the human health threats caused by exposure to wildfire smoke, flame retardants are also of concern. These flame-taming mixtures are sometimes used as a fire management technique. In an effort to fight wildfires, firefighters apply millions of gallons of flame retardants to U.S. lands annually, especially on the west coast.

Most retardants are a combination of:

  • Water (about 85 percent)
  • Fertilizer
  • Colorants
  • Thickeners (like clay)
  • Anti-corrosive material
  • Bactericides
  • Stabilizers.

Although the EPA labels fire retardants, like the commonly used Phos-Chek, as “practically non-toxic,” there is concern about its impact on aquatic life. These retardants may be lethal to aquatic life in rivers, lakes and creeks.

Scientists are concerned about the lingering effects flame retardants pose to trees and shrubs, especially during droughts when the chemicals remain on the plants for weeks or even months before being washed away.

To break down the potential health risks of wildfire smoke exposure, even thousands of miles away from the initial flames, here are the major suspected health impacts:

1. Respiratory System Assault

Even after the smoke clears, tiny particles remain suspended in the air. And inhaling this smoke pollution threatens respiratory system health. For instance, inhaling particles that linger in the air after a wildfire triggers reductions in lung function and lung inflammation.

One study shows that exposure to particulate matter can result in persistent coughing, the buildup of phlegm, wheezing, difficulty breathing and asthma symptoms.

Wildfire smoke also contains respiratory irritants, including formaldehyde and acrolein. Research indicates that these chemicals possess neurotoxic characteristics and systemic toxic effects. Plus, the negative effects of these irritants are known to increase as temperatures increase.

2. Immune Dysfunction

When particulate matter enters your lungs, it reduces immune function. This makes it harder to remove inhaled foreign substances that make us sick and irritated, including bacteria and pollen.

Researchers at the California National Primate Research Center and the University of California, Davis, found that when infant monkeys living outdoors inhaled wildfire smoke in 2008, they were more susceptible to infectious disease.

Compared to infant monkeys born exactly one year after the 2008 wildfires, monkeys exposed to particles after the wildfires experienced reduce immune system function.

3. Cardiovascular System Damage

When it comes to wildfire smoke inhalation affecting the cardiovascular system, the major culprit is carbon monoxide. When we carbon monoxide makes it way through the lungs, it enters the bloodstream and reduces oxygen to our organs and tissues.

Carbon monoxide poisoning, even at lower levels, can cause headaches, visual impairment, dizziness and reduced motor skills. Reports indicate that exposure to carbon monoxide can also increase the risk of heart issues, including cardiac arrhythmias, chest pain and other forms of cardiac dysfunction, especially among people with pre-existing health problems.

4. Increased Cancer Risk

According to the EPA, “people exposed to toxic air pollutants at sufficient concentrations and durations may have slightly increased risks of cancer or of experiencing other chronic health problems.”

More research is needed on the link between wildfire smoke inhalation and cancer, but scientists indicate that certain chemicals and compounds found in wildfire smoke, including benzene, formaldehyde and acrolein, may possess carcinogenic effects.

Some sensitive populations may experience more serious adverse reactions to wildfire smoke inhalation. These groups include those with respiratory conditions, including asthma and COPD symptoms, people with cardiovascular disease, children, the elderly, women who are pregnant and people who smoke.

How to Protect Yourself from Wildfire Smoke Near and Afar

1. Limit Your Time Outdoors

We know that wildfire smoke can affect people living close to the wildfire location and even those living hundreds or thousands of miles away. If the air quality in your area is compromised because of smoke or particle exposure, it’s important to limit your time outdoors with these EPA suggestions:

  • Stay inside and shut all windows and doors in order to reduce your exposure to air pollution.
  • If your home is in a very smoky area, find a designated clean air shelter. Public buildings with good HVAC systems, like libraries, malls and hospitals, are good options.
  • Avoid exercising outdoors until the air quality improves. When we exercise, our air intake increases as much as 10 to 20 times over our normal resting level, so you’ll inhale more pollution when the air quality is low.

2. Recirculate Clean Indoor Air

When you’re staying inside to protect yourself from smoke and air pollution, be sure to set your air conditioner to re-circulate air. You’ll also want to make sure that your filter is clean and functioning properly.

The CDC also recommends that you avoid creating air pollution while indoors, which means refraining from smoking, using gas, using propane or wood-burning stoves, vacuuming, burning candles and spraying cleaning products.

3. Use an Air Filter

To clean indoor air, you can use a portable air cleaner that contains a high-efficiency particulate air (HEPA) filter.

A two-year study conducted by the Intermountain Medical Center in Salt Lake City suggests that using HEPA filters in your home can significantly reduce fine-particulate matter in the air compared to non-HEPA air filters. In the study, the HEPA filters reduced particulate matter in the home by 55 percent.

4. Pay Attention to Public Advisories

One of the best ways to protect yourself from wildfire smoke and exposure to particles from smoke is to be aware of the Air Quality index in your area. You can check your local air quality report at AirNow.gov.

5. Reduce Your Carbon Footprint

Scientists agree that greenhouse-gas emissions from human activity are causing global temperatures to raise and changing the climate. This continues to impact the severity and frequency of wildfires.

The fossil fuels that we burn for energy, including coal, natural gas and oil, cause an overload of carbon dioxide and other heat-trapping gases in our atmosphere. What are some ways that we can reduce emissions?

For starters, you can eat more local and organic foods, walk or take public transportation when possible, reduce your meat consumption, reuse and recycle items and plant your own garden. On top of that, we need to elect leaders that support and implement climate solutions.

Final Thoughts

  • The very recent wildfires in California pose a health threat to thousands of citizens in the U.S. and across the globe. But the consequences of wildfire smoke inhalation stretch way beyond their places of origin.
  • Particulate matter pollution travels through the atmosphere for days and weeks after a wildfire.
  •  Climate change fueled by burning fossil fuels continues  to be a proven leading cause of more intense and frequent wildfires.
  • U.S. wildfire season is projected to lengthen and the severity of wildfires will increase.
  • To protect yourself from wildfire pollution, find a safe place to go inside and opt for HEPA air filters.
  • Avoid exercising outdoors if air quality advisories are in place for your location.
  • It’s necessary for U.S. residents to not only focus on carbon footprint reduction, but elect officials who will meaningfully take on climate change and transition to renewable energy and regenerative farming to stabilize the climate.

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