Air quality alerts issued in Canada and US as wildfires continue to burn

Millions of people are under air quality alerts as dense smoke blankets both countries

The smoke that has blanketed much of the US and Canada in recent days is expected to stick around. The Air Quality Index levels in many areas have peaked at "very unhealthy" levels, AirNow.gov reports. Officials urge residents to remain indoors.

What's causing the poor air quality?

Fine particles measured in the air, called PM2.5, have reached hazardous levels in some areas. The smoke is a result of wildfires in the US, specifically in Oregon, Idaho, and California. In Canada, smoke has been traveling south from fires in the Northwest Territories, pushing Ottawa's air quality to levels considered very unhealthy. The smoke is also responsible for the second-worst air quality in the world today: the town of Williams Lake, British Columbia, is reporting air quality indexes of 407, which is categorized as hazardous.

How it impacts people's health

People who are sensitive to air pollution may experience respiratory issues, while those who are healthy may experience some eye or throat irritation. Though the impact of the smoke will vary by location and individual, it's important to remain cautious.