Wildfire Smog May Ignite Increased Headache Risk

by Liz Neporent
June 8, 2023 at 9:05 AM UTC

Wildfire smog has been linked to greater risk of headaches.

Clinical Relevance: Wildfire-related air pollution can increase risk of headache

  • A study suggests that exposure to smog from the Canadian wildfires may cause a spike in headache-related emergency visits.
  • The smoke’s harmful contents may trigger headaches. Wildfire-induced anxiety can also cause tension headaches.
  • The CDC suggests staying indoors, using air filters, monitoring air quality, and wearing N95 masks to mitigate risks.

Over the past few days, a blanket of orange smog from Canadian wildfires briefly gave New York City the distinction of having the worst air quality in the world. A recent study suggests it could also lead to a jump in emergency visits for headache

Evidence Links Wildfires, Headaches

The authors of the recent Headache paper examined the records of nearly 10,000 Californians who went to the emergency department (ED) for headaches after being exposed to wildfire-polluted air for a short time. Most headache ED visits were by men – 76 percent. Over 40 percent were people between the ages of 35 and 54.

In the 15-year period the study covered, half of headache complaints were diagnosed as migraine. Another 40 percent were attributed to “other” types of headaches. Tension headaches made up about 10 percent of the cases. 

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And in a first, the study also found a link between cluster headaches and wildfire smoke. Cluster headaches provoke an intense, one-sided pain around the eye that can last for up to 3 hours. This type of headache comes on rapidly and occurs sporadically in “clusters” followed by periods of remission. Hence the name “cluster.”

In general, overall air pollution seemed to increase the risk for specific types of headaches. When the researchers factored in all types of particulates and not just what could be attributed to wildfire smog, they noted a 29 percent increase in the chance of ED visits for tension-type headaches. They didn’t see the same level of increase for migraine, cluster headache, or any other kind of headache.

Smoke’s Headache Connection

Why does wildfire pollution cause head pain? There’s no definitive answer.

According to an Annals of Indian Academy of Neurology study, wildfire smoke contains various harmful substances such as particulate matter, carbon monoxide, volatile organic compounds, and other toxic gasses. These pollutants can be irritating and toxic when inhaled, which can lead to inflammation and oxidative stress associated with head pain.

Thick, dense smoke reduces the amount of oxygen available in the air as well. This can cause hypoxia, or oxygen deprivation. An inadequate supply of oxygen to the brain can cause a headache. Particulates and gasses in smoke can irritate the mucous membranes of the eyes, nose, and sinuses, triggering a sinus or tension headache. 

Worrying about property loss and overall climate anxiety and depression can also provoke a tension headache, according to the Headache researchers. 

Reducing Health Impacts

The Centers for Disease Control and Prevention (CDC) recommends you reduce your risk of headaches and other health effects from wildfire air pollution by taking the following steps:

  • Stay inside with closed windows. Use high efficiency filters to capture fine particles from smoke. Use a portable air cleaner to reduce indoor air pollution. When air quality improves, even temporarily, air out your home to reduce indoor air pollution. 
  • Don’t add to indoor air pollution by burning candles or using gas, propane, woodburning stoves, or aerosol sprays. 
  • Create a “clean room” in your home with no fireplace and as few windows and doors as possible.
  • Know your air quality. Smoke levels can change a lot during the day, so wait until air quality is better before you are active outdoors. Sign up for local alerts and health warnings on your phone.
  • Avoid going outside during smoky times. Avoid strenuous activities such as mowing the lawn or going for a run. If you must go out, avoid the smokiest times of day. 
  • Wear an N95 respirator mask when you go outdoors. Learn how to use it properly. Don’t rely on dust masks or bandanas for protection from pollutants. 
  • Have a plan to evacuate. Know your evacuation routes, organize your important items ahead of time, and know where to go in case you have to evacuate.

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