Analysis of TRWP in the environment

Tire and Road Wear Particles (TRWP) are microscopic wear particles generated by friction between road surfaces and tire treads. These particles are a composite material consisting of rubber from tire treads and mineral particles derived from asphalt on road surfaces. Numerous reports indicate that TRWP accounts for a significant proportion of microplastic emissions into the environment. As a result, concerns have been raised about the potential risks TRWP poses to human health and the environment.
Within the EU, regulations known as “Euro 7” are being considered to regulate exhaust emissions, including fine particles generated by tire and brake wear.

Various methods have been explored for TRWP analysis. The ISO standard test method using Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS) is specified as the official method.

These standard test methods specify measurements for determining the content of styrene-butadiene rubber (SBR), butadiene rubber (BR), and natural rubber (NR) that constitute tire treads. SBR and BR produce vinyl cyclohexene, while NR produces dipentene as thermal decomposition products (markers). These markers are measured using the Py-GC/MS method to determine their respective rubber contents. Finally, the TRWP content in the sample is calculated based on these results.

We have extensive experience in investigating TRWP present in soil, river sediments, marine sediments, atmospheric dust, and other materials. In addition, we conduct various analyses related to TRWP investigations, including observations and element mapping using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). We also perform environmental surveys of additives contained in tires, such as vulcanization accelerators, anti-aging agents, and zinc oxide. Please feel free to contact us for more information.

◆Academic presentation on TRWP environmental survey
·Environmental survey of Tire and Road Wear Particles (TRWP) generated by friction between tires and roads (in Japanese)
Osaka et al., The 35th Elastomer Symposium,2022