European Tire Industry Addresses Environmental Impact Down to the Smallest Particle

Tires have been part of our world in one form or another for over 700 years, transporting carriages in the Renaissance era to electric cars, today.

In the beginning, tires were simply a curved piece of wood. Leather was eventually added to make the ride softer. Over time, leather was replaced by rubber. It wasn’t until the late 1840s when Robert William Thomson, a Scottish inventor, patented the first air-filled tire. And it took another 100 years for radial tires — what we use today — to hit the road.

Over time, as the only point of contact between a vehicle and the road surface, tires have evolved to make getting from point A to point B more comfortable, safer and more efficient. Today the tire industry is still looking at ways to improve tires, including how to optimize safety, performance, and make them smarter and more sustainable.

Among the industry’s focus areas are tire and road wear particles (TRWP), which are tiny debris formed during normal driving conditions due to the unavoidable friction between the tire and the road surface. Such friction ensures sufficient grip of the vehicle on the road that is critical for safety. TRWPs are super-tiny, elongated particles — in the range of 100μm, which is around the thickness of a human hair— and are comprised of both tire tread and road pavement material in approximately equal measures. While the size of the particles is relatively small, given that more than 1 billion vehicles travel the roads each year, it is important to understand their potential impact on human health and the environment.

A two-part study commissioned by the European Tyre and Rubber Manufacturers Association (ETRMA) and published in 2019, which analyzed how TRWP are transported through air, soil and water within the Seine watershed around Paris, provides some insight. According to models and environmental sampling, about 18 percent of the TRWP released within the watershed is eventually transported to local freshwater systems, and about 2 percent makes its way into the Seine’s estuary. Beyond waterways, low levels of tire and road wear particles have been found in airborne particulate matter in high-traffic locations in Europe, Japan and the U.S. To date, toxicity studies of airborne TRWP — sponsored by the Tire Industry Project (TIP), a voluntary CEO-led sustainability collaboration under the umbrella of the World Business Council for Sustainable Development — have found that human health risk related to short-term cardiopulmonary effects is low, although the authors note that additional research is needed to understand risk from longer-term exposure.

European tire manufacturers address the release of tire and road wear particles in the EU legislative context

Many factors can impact the generation of tire and road wear particles — including driving behavior and vehicle characteristics like weight, distribution of load and location of driving wheels, as well as the type of road surface. Even things like weather and tire design can have an effect. That means effective mitigation requires a collaborative, multi-stakeholder approach.

And that is where the European TRWP Platform comes in, initiated by the European Tyre and Rubber Manufacturers’ Association (ETRMA) together with CSR Europe in 2018. It is a multi-stakeholder initiative with experts from governments, academia, non-governmental organizations, and the private sector including the road and pavement, auto, tire and waste-water treatment, industries participating. “Through an open and inclusive dialogue, the Platform aims to share scientific knowledge, achieve a common understanding of the possible effects of particles generated during normal tire use and wear, and co-design mitigation options to reduce TRWPs in the environment,” says Fazilet Cinaralp, Secretary General of ETRMA.

In parallel, in 2018 the European tire industry began working on the important and unprecedented development of a representative and reproducible test method to determine the abrasion rate of tires, which could be used for regulatory purposes. ETRMA also advocates for more research and efforts to improve the composition of road pavements to decrease tire and road wear while maintaining safety. “The tire industry has been supporting research into TRWP for more than a decade; we’ve contributed a lot to the global state of knowledge, but it’s a complex topic with knowledge gaps that still need to be filled,” Cinaralp adds.

“I would definitely say that today our main goal is to identify feasible and effective combined actions to mitigate the release and transportation of TRWPs. Looking at the future, we are about to receive a State of Knowledge study, conducted by two leading research institutes to map the existing best mitigation actions, proposing the most efficient solution for each given situation. This study should help support, with scientific evidence, the best mitigation actions we can all implement to limit TRWPs in the environment,” she tells us.

The way forward

“ETRMA’s initiative to bring different sectors together to investigate and tackle the issue of tire and road wear particles (TRWP) is a perfect example of what the Leadership Model looks like in practice. It starts with a deep understanding of the responsibility of the industry but also about the limits of what it can do by itself. [TRWP] is not an issue concerning the tire industry alone, but it is now part of a wider agenda that deserves a wide array of action-oriented solutions by various industries and policymakers, including at the local — e.g., city and/or regional — level,” says Stefan Crets, executive director of CSR Europe. “This is a core element for the new agenda of the European TRWP Platform.”

The important role of the European TRWP Platform in involving different stakeholders and promoting constructive dialogues has also been recognized by the European Commission, which said that “the Platform will continue to play an even more important role in the work to reduce microplastics releases in the environment.”

This article series is sponsored by the Tire Industry Project. Members of the Tire Industry Project (in alphabetical order) are Bridgestone, Continental, Goodyear, Hankook, Kumho Tire, Michelin, Pirelli, Sumitomo Rubber, Toyo Tires, and Yokohama Rubber.

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