Bring on the firestorm....
This is more abbreviated than the one I read linked in another section of the forums here.
Yahoo left out where the nitrous acid is coming from. Most of it comes from "unvented gas appliances".
The only appliance I can think of that's natural gas and not vented is a gas stove; however, the Berkley Lab study does not mention what "unvented gas appliances" they are referring to. I would think if they were referring to a stove they would mention it and what percentage of the population uses one just to make their point.
If your natural gas furnace and/or hot water heater aren't vented, you have a much more immediate problem than "third-hand smoke"!8-o
The Berkley study also notes that "MOST" vehicles "MAY" emit "SOME" nitrous acid which "MAY" enter the passenger compartment.
I wonder what the carbon footprint is of the Indoor Environmental Berkley Lab? Seems like they are making 'busy-work' for themselves....