Numerous wildfires in Canada continue to send smoke over the Great Lakes region and portions of the Northeast, putting some residents at increased risk of respiratory and cardiovascular harm.
This year, drought conditions have sparked more than 400 wildfires in Canada and several fires in the United States, bringing smoke and hazardous air quality conditions to portions of the Midwest and Northeast.
According to Canadian authorities, as of June 6, about 106 fires are currently under control, 70 are being held, and 235 are still out of control, which means people in some regions of the United States will likely continue to experience air quality issues.
In an AccuWeather report, meteorologist Dean DeVore says, "The impacts to air quality have been unprecedented this early in the season when we've mixed in the wildfire smoke with the dust and other pollutants, including ozone at the ground level, during hot stretches across the Great Lakes and Northeast."
Because of these air quality issues, people living in these regions have observed strange hazy skies and vivid or obscured sunrises and sunsets — along with frequent air quality alerts.
What are air quality alerts?
Government officials issue air quality alerts when the air quality index (AQI) reaches unhealthy levels due to one or more of five pollutants regulated by the Clean Air Act. These pollutants include:
- Ground-level ozone
- Particle pollution (also known as particulate matter, including PM2.5 and PM10)
- Carbon monoxide
- Sulfur dioxide
- Nitrogen dioxide
In addition, there are six air quality alert levels, including:
- Good: Air quality is satisfactory
- Moderate: Air quality may affect people unusually susceptible to air pollution
- Unhealthy for Sensitive Groups: Those at risk for adverse health effects may experience issues, but the general public is less likely to be impacted
- Unhealthy: The general public may experience health issues, and sensitive individuals may have more serious health effects
- Very Unhealthy: The risk of health effects increases for everyone
- Hazardous: Everyone is more likely to experience adverse health effects
Currently, particulate matter from wildfire smoke is causing PM2.5 levels to reach "unhealthy for sensitive groups" and "unhealthy" levels in parts of Minnesota, Wisconsin, Michigan, Indiana, Ohio, and specific regions in the Northeast.
How does wildfire smoke harm health?
According to the EPA, while wildfire smoke contains a mixture of pollutants, particle pollution is the most concerning for human health. These particles are tiny, some only viewable with an electron microscope. Their small size makes them easily inhaled deep into the lungs. What's more, the particles can even enter the bloodstream.
The EPA says numerous studies have linked wildfire smoke exposure to an increased risk of cardiovascular and respiratory symptoms and conditions.
- Irregular heartbeat
- Nonfatal heart attacks
- Increased asthma symptoms
- Lung irritation, decreased lung function, or difficulty breathing
- Premature death in people with heart or lung conditions
Moreover, people most at risk for adverse health effects are older adults, pregnant individuals, those with cardiovascular or respiratory disease, children under 18, outdoor workers, and people of lower socio-economic status.
Because experts predict periods of unacceptable air quality are likely to continue, it's important to know what to do when officials issue an air quality alert.
During an air quality alert level of "Unhealthy for Sensitive Groups" or higher, people at risk should consider staying indoors and limiting the amount of time spent outside. Moreover, if a person needs to be active outdoors, they should stick to essential tasks and not overexert themselves.
In addition, if an individual begins to experience concerning symptoms while outdoors during an air quality alert, they should contact their healthcare provider.
- Canadian Interagency Forest Fire Centre Inc. National Fire Situation Report.
- AccuWeather. As historic Canadian wildfire season rages, US braces for more smoke and haze.
- EPA. Air Quality Index.
- AirNow. Air Quality Index (AQI) Basics.
- EPA. Why Wildfire Smoke is a Health Concern.
- National Weather Service. During an Air Quality Alert.