Climate change has led to higher global temperatures and earlier spring snow melt. Wildfire seasons are lasting longer: The U.S. Environmental Protection Agency (EPA) reports that the North American season has nearly doubled in length since 1984, now lasting from April to late September.
Canada is suffering through its worst wildfire season on record due to a combination of extreme heat events, unusually dry weather and lightning strikes. The fires have consumed more than 29 million acres since April—an area larger than the state of Kentucky and more than four times Canada’s national average for wildfires—resulting in the displacement of more than 150,000 residents.
Smoke from wildfires is the result of burning trees, buildings, plants and other materials. It consists of tiny solid particles that can enter the bloodstream after being inhaled, potentially leading to heart, lung or brain damage.
Once the smoke rises into the stratosphere, it can spread vast distances along an atmospheric highway; the Canadian wildfires have damaged air quality as far away as Spain. By early July, more than 70 million Americans had experienced eye-stinging pollution due to the Canadian wildfire smoke. The hazy, smelly smog would settle in a given location for up to a week, then dissipate and continue its journey governed by the jet stream.
The EPA has monitored air quality since 1976. Together with other government agencies, it created the AirNow system in 1998 to collect air quality data from around the United States. The Air Quality Index (AQI) came into use in 1999 as a means to inform the public about the safety of the air outdoors, along with any associated health effects.
The AQI level starts at 0 (perfect) and ranges up to 500 (immediate and potentially life-threatening danger from pollution). A level from 51 to 100 is acceptable, but it does indicate an increase of harmful particles that may pose a risk to some. Numbers above 100 mean that being outdoors is unsafe for high-risk individuals such as smokers, pregnant women, people over 65 or under 18, and those with heart or lung conditions, such as congestive heart failure or asthma.
As the number rises above 150, particulate pollution from smoke becomes a hazard to the general population as well, potentially causing eye irritation, coughing, headache, shortness of breath or fatigue. An AQI in the 200s qualifies as a health alert, and higher than 300 carries a health warning: Everyone who breaths the polluted air is likely to become ill. Short-term particulate pollution can injure the respiratory lining and stress an already damaged heart; long-term exposure is much more serious.
On June 6, New York City registered an AQI of 460, the highest reading in its history and the highest in the world that day. Being outside for 24 hours was like smoking six cigarette! Air quality alerts were also issued for the Hudson Valley, with Dutchess County registering well over 150. (The annual average AQI for this area is 41.) Schools closed early, and people were warned to stay indoors.
The best way to protect yourself from the dangers of wildfire smoke is to keep an eye on the local AQI and heed AirNow’s advice. If it reaches 150, at-risk people should stay indoors. If it goes above 300, otherwise healthy people are advised to remain inside. Windows should be closed, run your air conditioner with the fresh–air intake closed, or get to a cooling center. Keep your home air as pure as possible: Don’t smoke, vacuum or burn anything in the fireplace or stove. Consider using an air purifier. Stay hydrated and use nasal saline if your air passages are irritated.
To help your lung immunity and minimize inflammation, increase your intake of foods high in antioxidants: blueberries, beans, apples and greens. If you must go outside, an N95 mask works well to minimize your exposure to particulate matter. Those with heart or lung disease should ask their primary care doctors whether they should temporarily leave the affected area until the air is once again clear and registering a low AQI score.
The Canadian wildfire season is expected to continue through September without weakening; nearly 900 fires are currently burning, and new fires beginning daily. By staying alert to the air quality and the recommendations of AirNow, we can maintain good health.
Mary Jenkins recently retired after nearly 40 years as a family practice physician in New York state.