WTF are you talking about? You're not even in the realm of the study anymore with your rantings here.

from the abstract:

Gas and propane stoves emit nitrogen dioxide (NO2) pollution indoors, but the exposures of different U.S. demographic groups are unknown. We estimate NO2 exposure and health consequences using emissions and concentration measurements from >100 homes, a room-specific indoor air quality model, epidemiological risk parameters, and statistical sampling of housing characteristics and occupant behavior. Gas and propane stoves increase long-term NO2 exposure 4.0 parts per billion volume on average across the United States, 75% of the World Health Organization’s exposure guideline. This increased exposure likely causes ~50,000 cases of current pediatric asthma from long-term NO2 exposure alone. Short-term NO2 exposure from typical gas stove use frequently exceeds both World Health Organization and U.S. Environmental Protection Agency benchmarks. People living in residences <800 ft2 in size incur four times more long-term NO2 exposure than people in residences >3000 ft2 in size; American Indian/Alaska Native and Black and Hispanic/Latino households incur 60 and 20% more NO2 exposure, respectively, than the national average.

They took samples before and after gas stoves were turned on inside various rooms in various houses and they state all of that in the study that that shit came from the stove and increased the levels of NO2 above WHO standards and not the outdoor environment. They're stating that gas stoves are problematic especially in lower income dwellings.

Also FTFS:

Consistent with previous research (10, 24, 25), we find that combustion from gas and propane stoves represents a major source of long- and short-term NO2 exposure that can exceed U.S. and WHO guidelines just by using a stove, independent of any outdoor NO2 exposures.

So again WTF are you on about?