A little rubber becomes chemically incorporated into asphalt roads, because asphalt and rubber both are made of petroleum oils. But the vast majority wears off as small particles that are rinsed off the road by rain, or blown off by wind, ending up in the soil, on plants, and in lakes, rivers and streams.

What is the use of worn out rubber tires?

Some applications for crumb rubber include: rubberized asphalt, playground flooring, welcome mats, anti-fatigue mats and vehicle mud guards. Shredded or chipped tires can be used as both a liner and/or a cover for landfills.

What is considered a worn tire?

Tires are considered legally worn out in most states when the tread depth is less than 2/32". ... There's a quick and reliable way to check tread depth using a penny. Insert a penny upside down into the tire tread with Lincoln's head facing you. If any part of Lincoln's head is covered, the tread depth is still good.