Billions of road miles are driven every year, generating countless particles of synthetic rubber and reportedly one of the largest sources of microplastics to the environment. However, such estimates are in disagreement with environmental data where polyethylene, polypropylene, polystyrene and PET are the main types of microplastics and on a global scale only around 1% of studies report finding tyre particles; posing the question where are all the tyre particles? Here we summarise recent empirical evidence demonstrating the transfer of tyre particles to the environment by storm water, water, effluent form wastewater treatment and deposition from the atmosphere. Tyres contain a range of potentially hazardous chemicals, if their accumulation in the environment has been underestimated how concerning might this be, what mitigation measures might be appropriate and what lessons can be learned from previous work on other sources of microplastic contamination.