Notes
a car's tires emit 1 trillion ultrafine particles per kilometer driven—from 5 to 9 pounds of rubber per internal combustion car per year.
More than three-quarters of microplastics entering the ocean come from the synthetic rubber in tires,
Related is the damage done by heavier vehicles due to the fourth power law: https://en.wikipedia.org/wiki/Fourth_power_law
A 30 ton truck is about 10,000 times more damaging to the road than a 2 ton car.
