Hot, dry summers and autumns—and forest fires—seem to go together. In fact, there are “fire seasons” in many parts of the world.
This shows that no matter where people live, they need to know how to protect themselves from wildfire smoke.
In the US’s arid western lands, for instance, wildfires have been common occurrences for “thousands of years,” says the US Bureau of Land Management (BLM). Many are caused by lightning and other natural causes, but “approximately half” of wildfires are caused by humans, notes the BLM, which is dedicated to preventing both kinds of wildfires.
But today’s wildfires are also affected by the longer periods of drought, says the US National Oceanic and Atmospheric Administration (NOAA). “Wildfires require the alignment of a number of factors, including temperature, humidity, and the lack of moisture in fuels, such as trees, shrubs, grasses, and forest debris. All these factors have strong direct or indirect ties to climate variability and climate change,” says NOAA.
Experts do not expect annual fire seasons to shorten or moderate anytime soon, based on 1984–2015 data, so it is a good idea for people to learn how to protect themselves from the negative effects of breathing in smoky air.
This precaution is important for people in regions that are not prone to wildfires. For example, many of the northern US states in the Midwest and Northeast were blanketed by smoke from the Canadian wildfires in the summer of 2023. Eventually, the smoke traveled across the Atlantic to Spain and France.
Wildfires Are Becoming More Common
Climate change has made droughts more common, which means dryer forests and grasslands.
Studies have found that the dry conditions from climate change doubled the number of wildfires since 1984 based on data in forested areas in western US. Wildfire seasons are also longer and more active based on 1979–2013 data, says NASA, and the dryer conditions make these wildfires harder to extinguish, allowing them to eat up more precious woodlands and forests, homes, and even towns. Since 2016, 1.2 million acres have been burned due to wildfires.
If temperatures worldwide continue to rise, more wildfires are expected. Just a 1-degree Celsius temperature change is projected to increase the areas burned per year by as much as 600% in some types of forests, says the Center for Climate and Energy Solutions.
However, as of August 2, sixty-seven large fires and 388,245 acres were already burned in eleven U.S. states by wildfires so far in 2023.
Research from the Georgia Institute of Technology found that the smoke plumes from wildfires can worsen climate change by affecting the atmosphere. Thus, more climate change is expected to create more wildfires, and more wildfires are expected to create more climate change. It is a vicious cycle.
How Wildfire Smoke Can Affect Your Health
While someone may think that a bit of smoke is no problem, they may be damaging their lungs by breathing in particulate matter, carbon monoxide, and various toxic compounds found in wildfire smoke.
“The short-term effects depend on your lung health and any underlying health conditions,” says Michael Green, MD, an OB/GYN and cofounder at Winona. “For example, someone with asthma might experience worsened symptoms while breathing in contaminated air. Breathing in smoky air can also increase the risk of cardiovascular issues, such as heart attacks.”
“You may be damaging your lungs by breathing in particulate matter, carbon monoxide, and various toxic compounds found in wildfire smoke.”
Over time, says Green, breathing in smoke can contribute to chronic lung health issues and decreased function and capacity. Long-term exposure to particulate matter specifically can increase the risk for severe health conditions like COPD, strokes, and heart disease. [See The Earth & I, August 2021]
People who are most affected by wildfire smoke include young children, older adults, and those with cardiovascular or respiratory conditions like asthma, according to the New York State Department of Health. Some symptoms of smoke exposure include:
Irritation of the eyes, nose, and throat
Shortness of breath
Wheezing and shortness of breath
Just a few days of exposure to wildfire smoke can have severe health consequences, including:
Reduced lung function
Increased risk of worsened asthma or other lung diseases
Increased risk of premature death
How To Protect Against Wildfire Smoke
Staying indoors is good, but it’s not always enough, say experts like Tony Abate.
“Most of our homes are not totally sealed from outdoor air; this is why you feel drafts in the winter. This also means air laden with contaminants from Canada’s wildfire smoke will find its way into our homes and our lungs,” says Abate, certified indoor environmentalist and vice president and chief technology officer at AtmosAir Solutions, an air purification and monitoring technology company.
Still, “the best thing you can do for yourself is to stay inside,” says Green. From there, work to keep the indoor air as clean as possible. Limit indoor pollutants, such as smoke from candles, smoking, or using a gas stove since it is not safe to ventilate a home when it is smoky outside. From there, add additional steps to keep smoke out the lungs.
Running an air purifier can help. When shopping, be sure to look for air purifiers that can trap PM 2.5-sized particulate matter. Also, pay attention to how many square feet it can cover, as it may take several air purifiers to clean larger homes. Stock up on filters so there is a ready supply since smoky conditions can arrive without warning.
Proper maintenance of a home heating and air conditioning system is key, too. “The average air in a home can be a breeding ground for mold, dust, odors, bacteria, and airborne viruses,” says Abate. “Now, add wildfire smoke entering your home, and that can cause illness or discomfort.”
“The average air in a home can be a breeding ground for mold, dust, odors, bacteria, and airborne viruses,” says Abate. “Now, add wildfire smoke entering your home, and that can cause illness or discomfort.”
One way to deter smoke is to have a heating and air conditioning professional add bipolar ionization tubes to a home’s HVAC system, advises Abate. These devices continually emit ions into the air that attach to and neutralize airborne contaminants, including smoke, making the air cleaner.
Also, use a high-efficiency air filter with an HVAC that has a rating of MERV 13 rating or higher to keep the air clean. Then, set the air conditioner to “On” instead of “Auto” to keep the air circulating and continuously filtered.
If it is necessary to go outside, Green recommends wearing an N95 mask. Also, try not to breathe in deeply, since this can add damage to the lungs. That means no jogging, biking, skateboarding, or running to the bus stop.
Know When Air Conditions Aren’t Safe
Keeping an eye on the Air Quality Index (AQI) scores for the area is a good way to stay informed of smoky conditions.
“We’ve been seeing a lot of these AQI scores in the news recently. The Air Quality Index basically provides the public with the shorthand it needs to understand more complicated data on the concentrations of harmful pollutants in the air; in this case, the pollutant of concern is PM2.5,” says University of Richmond landscape ecologist Todd Lookingbill, professor of biology and geography, environment and sustainability.
The higher the AQI value, the greater the level of air pollution and the greater the health concern. If a person is a member of a sensitive group—like someone with asthma, an older adult, or someone suffering from lung disease—it is best to avoid prolonged outdoor activity when the AQI hits 100, explained Lookingbill. At 150, everyone should be paying attention and consider limiting intense outdoor activity and/or consider wearing a protective N95 mask. Once the AQI reaches 300 or more, the air is considered hazardous, and everyone should minimize outdoor exposure during these health emergencies as much as possible.
The best way to keep up with the AQI is to check the official government site AirNow.gov in the U.S. Just type in a location and the site will tell the AQI and if the air is safe. The site will also show maps of wildfires in the area.