Eewwww. I knew this, but it's nice to have it in the paper, where everyone else can see, and think about it.
Just one more reason that single occupancy vehicles, especially large, heavy ones, are not good for our environment, health, or society. All those bits of tire? You are breathing them into your lungs. And the pieces that don't get breathed in eventually end up in our soil and water. That sounds benign until you read all the toxic compounds that are contained in those little bits and pieces.
The next question is, "Where does the asphalt go that used to be in the roadway?" You know, that part that gets worn down by all the trucks, cars, buses, etc. Where does that go? Pretty much the same place.