i would be much more concerned about the hydrocarbons from vehicles that you have been breathing 24/7 all your life. i would be more concerned about the crappy air inside of buildings, including your home, where plenty of bromine and fluorine and formaldehyde and mercury out gas. i would be more concerned about fabric softeners and detergents, chemicals soaps, shampoos and cleaners, deodorizing products and sanitizers.
tobacco is a plant. burning tobacco is no different than burning wood or leaves in the fall. do you ever eat smoked meat? all of that has liquid smoke(smoke particulate dissolved in water) in it.
i could go on, but i assure you, second hand smoke from cigarettes is the least of anybody's problem, especially today.
btw, tobacco is a known preventative for the cytokine storm that kills with certain flus. i dont think second hand smoke would be enough to be effective. you would have to actually inhale it like everyone else.