Traditionally, one of the biggest issues facing the automotive and transportation ecosystem has been what to do with scrap tires. When they are no longer suitable for use on vehicles because of wear or irreparable damage, used tires can become a huge health and environmental problem.

There have been, however, major strides in developing sustainable practices for both the disposal and recycling of scrap tires. Yet some of these are not always evident, plus, with new developments in technology and recycling practices continuing to emerge, sustainable tire recycling continues to be a moving target.

As a rule of thumb, every vehicle on the planet scraps a tire every year. In Canada and the U.S., approximately 400 million tires are disposed of annually. In the past, old tires typically went to local landfills or were burnt - neither of which were good environmental strategies. Burning old rubber tires releases dangerous toxins and pollutes the atmosphere. And since old tires are not biodegradable, they take up more and more space in landfills over time, as well as becoming breeding grounds for rats and mosquitoes.

Before the states and provinces began to pass scrap tire laws in the 1980s, there were approximately 2 to 3 billion tires stockpiled in landfills across North America. Today, as many as 90% of those stockpiled tires have been recycled successfully. Old tires have gone from an environmental nuisance to a recycling success story over the last 25 years. According to the Environmental Protection Agency, about 85% of (or roughly 340 million) scrap tires now get recycled each year.

When buying a new tire today, the dealer usually recoups the old tire for recycling. Of course, some people might use their old tires for a new purpose, such as turning them into tire swings or garden planters. Alternatively, local community recycling centers constitute drop-offs for old tires to be recycled. Public awareness and educating younger generations to properly dispose of used tires is important so that they get directed to commercial reprocessing plants to be treated and broken down into materials that can ultimately be reused in making up new products.

Scrapped tire recycling should be industry-driven with some government support—two ingredients that vary widely throughout the world. Not long ago, tires were burned as an alternative fuel source to generate power (an undertaking still practiced in emerging economies).

Currently, more than 110 different products come from recycled tires in North America. Recycled tire rubber is used to make rubberized asphalt, which in turn is used to resurface roads. It also finds its way into all sorts of other products, including rubber-encased railroad ties, rubber composite decks, sports courts, running tracks, playground surfaces, public walkways, garden mulch, construction backfill, erosion control barriers, and even molded automobile parts, such as engine drive belts and floor mats.

New products derived from waste tires generate more economic activity than combustion or other low multiplier production while reducing the waste stream without generating excessive pollution and emissions as a result of recycling operations. There are tire recycling business opportunities around the world. The process is sequential, evolving from TDF (tire-derived fuel) to mulch (natural or colored), to crumbs and fine powder. Steel and fibers from processed tires are recycled, and a current state-of-the-art process is to devulcanize the rubber with which to make new products (mixed to given ratios with non-recycled rubber, depending on the stringencies of the applications).