The benefits of reusing tire scrap are obvious. It diverts millions of tires from the solid waste stream. It saves energy and resources. It avoids new or additional toxic manufacturing inputs. Heaps of scrap tires are no better than reservoirs loaded with fly ash from coal fired power plants. Both fly ash and tire scrap are on the edge of being classified as hazardous wastes. Pollutants rise from festering pools of ash and smoldering piles of tires. The toxic compounds fall into nearby communities. Beneath these stews, heavy metals and polyaromatic hydrocarbons migrate into streams and aquifers. But does shifting these wastes indoors represent a positive alternative?
Avoiding Contaminants in Tire-Derived Flooring describes the origins and fate of crumb rubber used in building materials. It concludes that tires contain a host of toxic ingredients to which people may be exposed when this material is brought into homes, schools, gyms and offices.