So, fun fact, huge differences in efficiencies of removing pollutants even for vented range hoods. https://www.osti.gov/servlets/purl/1420274 https://www.osti.

So, fun fact, huge differences in efficiencies of removing pollutants even for vented range hoods. https://www.osti.gov/servlets/purl/1420274 https://www.osti.gov/servlets/purl/1420274 (Kinda long...) tl;dr those stupid microwave exhaust vents may only remove, at worst, ~25% of no2 from the environment. A cheap hood, 30%. A really good hood, 90%.