Tire-Abrasion Particles in the Environment

Driving a vehicle on a road is inevitably associated with the generation of tire-abrasion particles. Annually, nearly six million tons of this material are released into the environment globally. Most of the tire debris is encrusted to variable extent with other particles, which are derived from brake and road wear, as well as from soil. First emitted into the atmosphere or deposited onto the road surface, these tire-abrasion particles are subsequently transported by wind and water to different environmental compartments, whereby road runoff plays a crucial role in the distribution. Once in the environment, these particles interact with air, light, and water, which triggers degradation and concomitant release of crucial tire components, such as zinc and various organic tire additives. The tire-abrasion particles and the leachates derived from them during their degradation in the environment can cause various biological responses in aquatic and terrestrial biota, as determined by numerous ecotoxicological studies. Challenges exist with the identification and quantification of the abundance of tire-abrasion particles in the various environmental compartments, the determination of their toxicity, and with the reduction of both their emission and immission into the environment.