All that nasty pollution coming from vehicle exhausts must go somewhere and buildings are normally rather close. Then, if some neighbor asks you who is making his / her home looking dirty, you should admit that you are also responsible if you drive a combustion vehicle with an exhaust by there.
In fact, there aren't exclusively buildings; after months, anything near constant traffic will have residues of combustion. These are inherently dark particles, normally black that go to any place like your hair, skin, meal, drinks, etc. It's difficult to see them after coming from the exhaust because they are microscopic but nothing stops the aforementioned accumulation... the proof that they are also inside your body.
Nature has a curious way of handling these substances, because some of them are stored in the organism creating different problems until some technique achieves to take them out. It acts like a punishment for individuals that don't take care of their health. Specially at advanced ages, all that you did will appear like an expensive bill.
If a hundred vehicles are passing through a bridge of one kilometer, each five minutes more or less a ton of carbon dioxide would be produced in that area. The most important part of air pollution is evidently from combustion vehicles, so did you hear about using bikes, traditional walking or public transport? If you like luxury, space, seats and so on transporting a heavy vehicle that weighs more than a ton, there are some options with electric vehicles and units for harvesting energy 100% free and clean as always.
It's difficult to hide, even if you sell black gold, that the Sun provides more power and free than all those work to destroy your own habitat employing hydrocarbons. Let's avoid puerile and costly behaviors while keeping buildings with a good looking impression, for the history.