Depends on who you believe. Treehugger reported on a “study” saying we do, complete with accomplices who sell filters. Be sure to check out Ruben’s comment about some cool DIY filters and the add-on, “I also put a lanyard on my filter, so I could spit it out to yell at bad drivers.”

I don’t know. When I’m behind a bus at a redlight, I try to breath…less. But sometimes you can’t help it and keep taking in clouds of who-knows-what deep into your lungs. Right when I went car-free, I noticed that puffs from vehicles affected me more, though I think that might be largely psychological, one way or the other.

I am no expert (my degrees are in philosophy, lol), but maybe the damage to our lungs is offset somewhat by the fact that we work to get places, that we’re not sitting on our big asses in traffic, texting our friends about the great breakfast sandwich we just got at McDonalds.  Exercise like cycling around [hilly] Baltimore can’t be bad for you, can it?

And I swear I read somewhere that the air inside of cars is as bad, sometimes worse, than the air outside.