How bad is wildfire smoke for kids?

What the evidence says

Wildfire smoke is a mix of tiny particles and gases that gets into the air, sometimes from fires thousands of kilometres away. Health Canada says the main danger comes from very small particles called PM2.5, which are too small to see but can get deep into the lungs. There is no level of this pollution known to be completely safe, and risk goes up the more smoke there is and the longer someone is exposed to it.

Kids are hit harder than adults for a few plain reasons. They breathe faster for their size, they tend to be more active and spend more time outside, and their lungs and airways are still growing. A Canadian study of Calgary children with asthma found more asthma flare-ups on wildfire smoke days compared to normal days. A separate review of children across Canada, the US, Australia and Spain found a clear jump in emergency visits for breathing problems in the days right after smoke exposure, especially in kids under 5.

Most of the time, symptoms are mild, things like a scratchy throat, coughing, watery or stinging eyes, a runny nose, or a headache. These usually settle down without needing a doctor once the air clears or the child is moved somewhere with cleaner air. Less often, smoke can cause more serious problems like real trouble breathing, wheezing, or chest tightness, and children with asthma or other lung conditions are more likely to have bigger reactions.

To protect kids, keep them indoors with windows and doors shut during smoky periods, use a portable air cleaner if you have one, and skip outdoor sports or heavy play on smoky days. Cloth masks and wet washcloths do not filter out smoke particles. A well-fitting N95-type mask can help older children, but it needs to fit properly and most are not made for young kids, so it is not a reliable option for toddlers.

If your child has asthma or another breathing condition, talk to their doctor ahead of wildfire season about a plan for smoky days. Watch for real trouble breathing, blue lips, extreme sleepiness, or not eating or drinking, and get medical help right away if you see those signs.