"Man-Made" Natural Filters

You know how I'm very capable of thinking up a bunch of crap, right?
My trail of thoughts includes stuffs like when you do those chemistry experiments and you have to test the gas coming out of the test tube so you close the mouth of the tube with a finger to prevent it from going out, right? Well, I thought what if you're allergic to say... NH3 gas?? Or worse, H2 gas!! Would you give up your beautiful finger for your lab test?
OK, I know it's stupid.
Oh, and I also thought of a way to reduce pollution and the amount of smokers at the same time. All of us feel annoyed of being the second-hand smokers, right? So how do you prevent the smoke from the stupid smoker travelling into "your territory"? Of course, you make sure the smoke is contained in an area. How do you make this happen? We can build smoking rooms who nobody uses, OR we could tie a plastic bag around the smokers head so the smoke he gives out stay in that bag. And since it's tied around his head, he won't have to go through the trouble of holding it up. As for the little problem where he can't move the cigarette around because the plastic is in the way, well, all I can say is "Learn to adapt". Easy and practical. If some of you feel like "How are they going to breathe then?", notice I said "REDUCE THE AMOUNT OF SMOKERS", in other words, they'll just drop dead like flies. As I see it, if they love inhaling that gas so much, they might as well not waste a single bit of it.
While we're still on the topic of smoking and lungs, let me bring you to the main point of this blog: "Man-made natural filters".
Lungs. They are amazing, aren't they? So, anyway, if you smoke, residues of the smoke (tar) get left behind in the lungs, right? I mean it's like a filter paper, you put murky water true it and clear water comes out whereas the filth gets left on the paper.
I'm going to use that as the basic concept for lungs, dirty air goes in, exchange of oxygen and carbon dioxide happens, filtered air comes out.
So, what if... (please notice that this is just a thought). What IF we breathe in smelly air like say, someone farted a nuke in the car and there's no way to wind down the windows. That would mean the fart-air would be in the car for a long time which will eventually end up in our lungs. I bet a lot of you already know what I'm going to ask.
What happen to the fart-residues in the air? I mean like, smelly (regardless of nice or bad) is because the small particles of the thing that's giving out the smell is floating around in the air, you breathe that air in, those floating particles go in as well.
According to my previous Filter Paper Theory, air filled with those particles goes in and air lacking of those particles comes out. In the case of smoking, the tar residue gets stuck in the lung which leads to lung cancer, right? So in the case of the fart incident, does that mean the fart-particles get stuck in our lungs?
When you think of it this way, all those dirty smells we smell everyday enter our lungs (like duh~ or not why would you be able to smell it!), right? Which means all those dirty filthy particles are getting stuck in our lungs everyday, little by little....
Eeewww~ Imagine how dirty your lungs are and how smelly they would be if you opened them up!!

PS: This post has 0.00% of scientific facts in it.