 since nineteen seventy what comes out of your tailpipe i wouldn't uh... i would advise people closer garage is still some things that are harmful in there but we've done a tremendous job in reducing pollution uh... in our eras cleaner now i can remember days when when i was a child we're driving past gary gary gary steel mills and northwest indiana and a film covered our windshield is we're driving on their on the expressway we had to pull up and wipe the film out there was in the air