Obviously it's better than nothing, I live in a city, less polluted than the leaders like Hanoï, Shangai, etc.., but strangely, I already expressed it on this site, I have a sort of disproportionate fear of other pollutants such as cigarettes smokes. I would be interested to know which of car exhaust and a smoker smoke, at comparable concentration, is more 'noxious'.
In my case, during the day, bike or walking outside, I really feel more sporadically tobacco smoke (40%+ smokers in my area), than other pollutants. And like I said I still can't get over the feeling than the first is more noxious than the second.
So I would like to understand once for all how does second-hand smoke compare to car pollution? Do the particles have same size properties (from 0.3 to 2.5 microns concerning car pollutants PM0.3-PM2.5 which are (mostly) retained by common pollution masks)? So could those masks work as well for second-hand pollution (marginal for most people, but still there)?