Where does tyre wear go? Separating and quantifying rubber in environmental samples

With the on-going roll-out of electric vehicles, tyres and their associated emissions are potentially becoming the biggest source of pollution from motor vehicles, but measuring them is hard. It is an important area as tyres have been identified as potentially the largest source of microplastics in the ocean, as a result of run-off into water courses. Emissions Analytics has been leading the development of real-world test methodologies, both for tyre wear rates, but also to profile the chemical composition and potential toxicological effects of the wear on humans and the wider environment. Initial work on potential regulation is underway at the United Nations.

Tyre wear is more complex to measure than other emissions, including tailpipe, because tyres are part of an open system, where material abraded from tyre is 'sprayed' into the environment, where it mixes with other material - brake wear, road wear, resuspended dust and pollution from other sources. The challenge, therefore, is to be able to take a sample from on or near a vehicle and being able to estimate with good accuracy the tyre wear material contained in it, separately from the non-tyre components. Each of those pollution sources has a different chemical fingerprint, or contains unique tracers that can help separate them from each other. Without such separation, while we can measure the material lost from a tyre, we cannot fully understand in what form it is shed and where it goes.

Emissions Analytics has an existing capability to measure the organic constituents of tyre wear using an in-house state-of-the art chemical analysis, using which it has developed a tyre fingerprinting database for the potentially harmful carbon-containing compounds in tyres. It has also developed a patent-pending system for physically sampling tyre wear material on a vehicle as it drives around in the real world. Therefore, many of the components required are in place to address the problem, but additional analytical expertise in both sampling optimisation and source apportionment data analysis is needed to achieve a high quality, market-ready offering.

Therefore, by addressing this sampling and measurement challenge, there is the potential to unlock private sector value together with a public value in addressing current and pre-empting future environmental challenges. For Emissions Analytics, it would form an additional element to its growing suite of tyre analysis services.