What are tire and road wear particles (TRWP)?
TRWP are tiny debris produced by necessary friction between tires and road surface; they are an approximately half-and-half mixture of tire tread and road pavement material. With a density of ~1.8g/cm3, TRWP are expected to sink in water.
Since 2005 the Tire Industry Project (TIP) has supported research into the potential human health and environmental impacts of tires throughout their lifecycle.
The peer-reviewed studies we have sponsored to date have found TRWP are unlikely to pose significant risk to human health and the environment; however, we are mindful of an evolving scientific understanding of TRWP, including some research that has reached different conclusions, so we continue to support independent research to improve the knowledge base.