N02 – a pollutant that causes asthma attacks and EPA says there is “now stronger evidence” that long-term exposure causes asthma in otherwise healthy children. I love talking about formaldehyde as much as the next “stover” — but the one pollutant that consistent blows EPA health-based standards (NAAQS) is NO2.
EPA https://cfpub.epa.gov/ncea/isa/recordisplay.cfm?deid=310879
“The cumulative body of evidence indicates that short-term exposure to NO2 can cause respiratory effects, in particular, effects related to asthma exacerbation. Recent results also strengthen the evidence that the respiratory effects of short-term NO2 exposure are independent of the effects of many other traffic-related pollutants. There is now stronger evidence for a relationship between long-term exposure to NO2 and respiratory effects, particularly the development of asthma in children.”
Another air pollutant from gas stoves is formaldehyde, which Lawrence Berkeley National Laboratory started publishing copious amounts on starting around 2011, following their extensive study of second hand cigarette smoke. Here is a table illustrating the excessive amounts of Formaldehyde found in homes with gas stoves: https://eta-publications.lbl.gov/sites/default/files/hazard-assessment-lbnl3650e.pdf