[tzs]

For most commutes the car would still win even if the air inside was the same as the air outside, because the car would be faster so you would have less total exposure.

As far as car interior air goes, I've noticed that when I walk to a nearby market during times when there is a fair amount of traffic I can really notice the smell from the cars, but when I myself am driving on that same road in similar traffic I cannot smell it.

My guess is that the rate of exchange of air between the car and outside is low enough that at least for short trips (a few miles, say) it mostly remains air that was from my neighborhood, which is half a mile away from any heavy traffic road.

Note: this is without using the AC.

[05]

Also you’re not breathing as much as when you’re biking.