What’s that smell? Smoke from Canadian wildfires emitting particular scent
https://www.wpxi.com/news/local/whats-that-smell-smoke-canadian-wildfires-emitting-particular-scent/XLZWQ5WC5RDALISQUUUBBVZM6A/
Isoprenoids are compounds released when vegetation burns. Those compounds produce what we think of as a wood-burning smell or “campfire” smell. Well, those compounds break down quickly when exposed to UV radiation from the sun. Hence, the scent doesn’t travel too far.
What does carry a distance are volatile organic compounds like Benzene, Formaldehyde and Acrolein which all have a more pungent, sweet or metallic smell. That is what most of us have been smelling when stepping outside the last couple of days. Benzene is particularly dangerous, with long-term exposure, which is one of the many reasons we are encouraging you to stay inside while the air quality is so bad.