Now if only these same "scientists" could do a "study" on noxious gases (carbon monoxide) emitted from automobiles and it's effect on our health.
Sorta odd how folks who don't smoke contract like diseases.
Any one who lives in a climate where it snows realizes what filth is coming from cars.
Looking at a plowed snowbank about a week after a snowfall would make someone from another planet think that snow was black.
They can't blame that on the smokers(although I'm sure someone will try).