Smoke from wildfires in Canada has moved into Quebec and will reach Maine later Friday.
Martha Webster, Air Quality Meteorologist with the Maine Department of Environmental Protection, said the state will experience moderate particle pollution through the weekend and possibly into Monday.
"The health message for moderate level is that sensitive people should avoid prolonged activity. Watch for symptoms of coughing or shortness of breath. These are signs to take it a little easier," Webster said.
Webster says the DEP has learned more about why smoke has a larger impact when there is moderate particle pollution.
"We're starting to think it has something to do with the way smoke reflects and refracts light. There can be more visibility degradation at a given level of particle pollution if it's smoke," she said.
Webster said if you can see the smoke and smell it that you should avoid prolonged activity outdoors.
The DEP said it will monitor air quality and issue an alert if conditions worsen.