4. Conclusion and outlook

Non-exhaust particles (NEP) from tire-road contact represent an emerging part of the fine particle pollution linked to road transport. They include particles directly associated with vehicle use, the main components of which are tire-road wear particles (TRWP), brake wear particles (BWP) and resuspended particles. Knowledge of TRWP emissions, their fate and their effects on health and ecosystems remains limited. These particles result from friction and shearing between tires and road surfaces, and their characteristics depend not only on tire composition and road surface, but also on vehicle behavior and the environment through which it passes. While laboratory studies enable us to analyze emission mechanisms while limiting contamination, they do not always reflect real-life conditions. The absence of a standardized experimental approach makes it difficult to compare results from one study...