Polycyclic aromatic hydrocarbons in consumer goods made from recycled rubber material: A review

Vast amounts of rubber waste are produced every year, where end-of-life tires (ELT) mount up the largest share with several million tonnes in the EU each year. This points up the necessity for reusing end-of-life rubber material. The recycled material shows nearly the same advantages like the origin materials. In consequence, the recycled material is predestined for the use in sport facilities, which explains that around half of the recycled ELTs are used to produce artificial turf, sports flooring and injury-prevention pavements on playgrounds. Since tires contain potentially toxic components, there is worry concerning the release of such chemical substances stemming from these products. As tires contain highly aromatic oils and carbon black, the presence of polycyclic aromatic hydrocarbons (PAH) and their carcinogenic properties are discussed controversially. This review issues a comprehensive overview of PAH release and a conclusive assessment on human health risk. Analytical studies dealing with the PAH content of consumer goods made from recycled rubber material and associated risk assessments are reviewed. In conclusion PAHs can be detected in consumer goods made from recycled rubber and are released into the environment. They reach humans via leaching (soil, ground water, rivers), oral intake, dermal exposure and inhalation. Thereby, dermal contact or inhalation is the primary route of exposure, whereas oral intake and environmental pollution are regarded as secondary risks. The amount of PAHs that could potentially harm humans is in the magnitude of urban pollution. Risk assessment studies reviewed in this article show no serious risk potential.