Likely due to wild fires all along the inner coast on both sides of the border:
https://firms.modaps.eosdis.nasa.gov/map/#d:24hrs;@-121.6,48.5,7.5z
Try to reduce time spent outside and wear a K/N95 or P100 mask if you do.
Look into purchasing (or making) an active air filtration system for your home:
*The linked service (Windy) adheres to the WHO’s AQI standards which more heavily weigh levels of PM2.5 (particulate matter 20 times smaller than a human hair) and I only post these because the government, nor any of the news services, report this at all.
¯\_(ツ)_/¯



Environment Canada and provincial governments definitely measure and report PM2.5 all over the country. They post warnings when it exceeds safe levels.
https://www.env.gov.bc.ca/epd/bcairquality/readings/find-stations-map-PM25.html
Yes, but they use their own standards, not the ones set by the WHO which are more in line with the science behind the health effects of pm2.5. The safe levels according to the government aren’t that safe.
Interesting. Would you have a source handy that I could check out? Thanks.