Mapping the tire supply chain and its microplastics emissions using a multi-stakeholder approach

The important contribution of tires to microplastics found in the environment raises the question how to effectively mitigate the environmental release of tire microplastics. The aim of this study is to map the tire supply chain and quantify the resulting tire microplastics emissions in close collaboration with stakeholders, thereby providing a solid foundation for the development of a mitigation strategy. To this end, the supply chain was mapped and used to identify stakeholders and to quantify microplastics emissions using a material system analysis for the Netherlands, 2021. Stakeholder involvement was integrated for data gathering and to build trust for future collaboration. The total initial tire microplastics emissions were estimated at 19,580 t/y (85 % by tire wear and 15 % by infill). Approximately 9,450 t/y of tire microplastics were estimated to reach the environment, 80 % to soils and 20 % to surface waters. This is the first step towards an effective mitigation strategy.