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How Tires Pollute the Earth

By the end of 2003, more than 200 million tires were being produced in the United States annually, according to the U.S. Environmental Protection Agency, EPA. Although the tire-manufacturing process produces polluting emissions, the disposal of used tires causes worse problems for the environment -- polluting the soil, air and water -- and harms human health. In the last decade, many tire manufacturers incorporated improvements into the production process and changed tire constituents to make a greener tire. Recycling of used tires has increased to about 80 percent, the EPA reports, but a greater global effort is required to further reduce pollution of the Earth by tires.

Manufacturing Process
- About 30 to 40 chemicals go into the manufacturing of new rubber tires. Natural rubber, made from latex sap, and synthetic rubber, which is produced from oil, make up major components of a conventional tire. During manufacturing, both particulate matter and hazardous volatile pollutants are released. Particulate pollutants are produced during milling, mixing and grinding processes, while airborne pollutants are emitted during processes that generate heat and use solvents and cementing liquids. A shift to more environmentally friendly processes by manufacturers include the use of renewable source materials, stopping the escape of air pollutants, the reduction of petrochemical use, and recycling of waste products.
Disposal and Storage
- Disposal of used or scrap tires is a huge environmental problem. Rubber tires take up large amounts of precious space in landfills and tend to rise to the surface, disturbing landfill covers. Stored piles of scrap tires are unsightly, harbor rodents and snakes and provide a breeding ground for mosquitoes, which may carry diseases, such as West Nile virus.
Tire Fires
- Piles of scrap tires cause the greatest damage to the environment when they catch on fire. Large piles of tires build up heat and are prone to fires. Tire fires are difficult to extinguish and tires can smolder and burn for weeks or even months. Burning tires break down into oil, toxic heavy metals and hazardous gases. Tire fires produce a thick black smoke that contains benzene, phenols, polycyclic hydrocarbons and other toxic gases. The burning of an average car tire produces more than two gallons of oil. The oil will seep into the ground and can contaminate groundwater. Runoff can contaminate surface water. Often, neighborhoods near tire fires have to be evacuated.
Reducing Tire Pollution
- You can reduce tire pollution in the environment by extending the life of your tires, reporting illegal tire dumping, and making sure that your old tires are properly recycled. Proper maintenance of your tires leads to longer periods between tire replacement and fewer scrap tires. Most states in the U.S. have laws that regulate scrap tires. Find out about your state's tire recycling laws and programs from your local waste management office. Programs for recycled tires include the transportation of tires to foreign countries for retreading and the use of tires in new applications, such as tire-derived fuel and rubberized asphalt. You can help promote tire recycling by purchasing products made from recycled tires.

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