ISO/TS 22687 and Environmental Fate of Tyre and Road Wear Particles

The potential environmental impact of microplastics is well known. Plastic particles impact negatively on air quality, soil and water, as well as on humans and other species of life. The drive to reduce the all-pervading nature of plastic emissions remains at the forefront of environmental best practice.

Europe’s largest motoring association, the German organisation Allgemeiner Deutscher Automobil-Club (ADAC), has released an evaluation into tyre wear particles, examining both the environmental impact and their effect on tyre safety.

According to the European Tyre & Rubber Manufacturers’ Association (ETRMA), these tyre and road wear particles (TRWP) – generated by friction between the road and tyre surface –include a mixture of tyre tread fragments and road surface elements. As such, they are known as ‘unintentionally released microplastics’.

ADAC’s evaluation states that more than 500,000 tonnes of tyre abrasion particles are produced annually in the European Union. Such synthetic rubber particles account for one-third of all microplastic abrasions in Germany alone.

While such particles tend to be sufficiently coarse not to be absorbed into the human respiratory system, they still account for a significant amount of road debris, which makes its way into the soil and waterways.

A question of balance

However, the need to reduce tyre abrasion for environmental reasons must be balanced alongside the need for manufacturers to produce a high-quality product that satisfies drivers in terms of safety and longevity. Friction may generate wear, increasing microplastic emissions, but it is needed to provide grip and therefore perform an essential safety function when driving.

The study of TRWP is a wide and complex field, according to ETRMA’s Secretary General Fazilet Cinaralp.

A number of ISO standards on TRWP have been introduced in recent years, not least ISO/TS 22687 2018: framework for assessing the environmental fate of tyre and road wear particles. This work was principally led by the Tire Industry Project (TIP), under the World Business Council for Sustainable Development (WBCSD).

Meanwhile, the July 2018 launch of the European Tyre and Road Wear Particles Platform has created a forum for stakeholders to share and build scientific knowledge about the challenges presented by TRWP, as well as conducting research into mitigation options.

“There is a very strong scientific community behind the Platform,” says Cinaralp. “Since its launch, we have seen an increasing interest and participation from universities, the scientific community and international organisations, as well as European and national authorities. All the industry stakeholders that have a role in what happens when the tyre hits the road – the vehicle industry, the tyre industry, the road industry, as well as waste water treatment – are involved in the Platform today.”

Perpetual innovation

Recognising the problem of tyre emissions is one thing; resolving it demands intensive work-in-progress.

“It is the job of everyone in the industry to balance the performance of a tyre and so it is subject to perpetual innovation,” Cinaralp says. “A tyre goes on the road with a driver who is different in each vehicle, and it must work on every road and in every driving condition. The industry must balance all of these factors, as well as taking into account sustainability factors.

“Driver behaviour is key, because the way we drive our cars is so different and we cannot standardise that,” she says. “Tyre design is, of course, very important but there are these other factors, such as driving style and vehicle and road characteristics, that we need to investigate to see how we can mitigate the impact.

“With the current technology, friction will always leave something on the road: particles that are composed of rubber, but also of road dust. These particles, which can be rather large, are going to stay there for some time. So, the question is, once released, what can we do with these particles? This is the other part of the platform’s activities; bringing together local and national authorities to work together so that best practices can emerge.

“It is a continuous process, not something to act on once and then forget about it; the learning needs to be refreshed continually. We believe that bringing stakeholders together through the platform can serve as a catalyst to multiply the initiatives in different countries and at different levels. Hopefully, in the coming months, we will be able to launch some joint pilot-level actions.”

Attribute to original publisher/ publishing organization: Fazilet Cinaralp, Secretary General of the European Tyre & Rubber Manufacturers’ Association, https://www.quality.org/knowledge/reducing-microplastic-emissions-tyres