Eugene:
Since you are under the impression that the air coming out of your SUV's tailpipe is cleaner than the air going in, I would imagine you have a flexible hose attached to your exhaust and blowing into the passenger compartment.
Trees and plants will do a heck of a lot more for me during my lifetime than any exhaust from any vehicle.
Yes, I am a tree hugger and proud of it.
Bountyhunter