This is the title of this blog post followed by this other good post. I'm particularly anti-tobacco-smoke, at the point of not always considering other pollution, and this article shows how this kind of domestic pollution (main domestic pollution is usually heating) is probably no insignificant in the global air pollution.
The weight of this pollution is also maybe increased since people tend to be nearer from potential smokers than from cars (e.g. near entrances). I've not known the period of the past, without the smoke-free laws in buildings, but it seems in my country, that it has just moved the problem, possibly reinforced smokers reflex to smoke when outside
The author shows useful references, that all measure second-hand smoking in terms of PM2.5 which is the common indicator with PM10 for air pollution [car traffic,domestic heating,industry,coal combustion,construction,quarry,waste treatment].
The results are interesting showing the important rate of PM2.5 in second-hand smoke, it would even be very useful to indicate air pollution levels in terms of cigarette inhalation. 0.17 cigarette/day is quite more insightful than 150μm of PM2.5, at least to me.
But I'm still skeptic and think the effects of second-hand smoke are more important (second-hand smoke is smaller in size than 1μm, considering not only cigarette from manufacturers which include many brute carcinogens and poisons (arsenic, hydrogen cyanide,..), but other tobacco/or drug smoking that are different but considerably noxious too)) and this study is quite informative too, comparing diesel car exhaust to cigarette combustion.
- is the pollution from cigarettes as volatile as the rest of air pollution?
- is the concentration of second-hand cigarette global pollution not insignificant compared to the rest of pollution (in countries with high smoking rates)?
- does it go in higher layers of the atmosphere, lower layers (more critical), or does it blend uniformly?
- can air pollution mask (with PM2.5, and PM10 reduction filter) protect as well from it?
particles size in micrometer, from http://en.wikipedia.org/wiki/Particulates
edit: this http://ash.org/CAEPAProposal.pdf report is particularly interesting