Why tyres are next on the emissions hit-list

Automotive is honed in on reducing CO₂ emissions, but the industry could start looking at other types of emissions as it works to make itself ever cleaner and greener

Emissions legislation has worked hard to reduce the amount of carbon, NOx and particulate matter emitted by vehicles. But as the numbers drop, focus shifts to what else can be done to make automotive even cleaner.

And although it isn’t often an element that’s talked about, the next area to receive attention could be tyres.

Non-exhaust emissions are of growing environmental concern with tyre emissions under significant scrutiny. The EU-commissioned research paper ‘Plastics in the Marine Environment’ found that tyres were the leading single cause of marine microplastics, amounting to 270 million tonnes per annum.

That makes it crucial that as an industry, automotive develops its understanding of the nature and magnitude of the challenge. Some firms have already developed systems to help reduce tyres’ environmental impact.

The product of over two years of testing and evaluation, Emissions Analytics launched EQUA Tyre, an organic compound profiling and benchmarking database, containing test results and raw data from independently-sourced samples from over 40 manufacturers and hundreds of different models of tyre.

Emissions Analytics’ founder and chief executive officer, Nick Molden, says: “Tyres are rapidly eclipsing the tailpipe as a major source of emissions from vehicles, but the nature of tyre wear is poorly understood. The new EQUA Tyre database marks a milestone in measurement, and which can offer a foundation for developing solutions.”

It’s all in the compounds

Tyres are a complex mix of components and compounds. To be able to separate and identify all the organic compounds, Emissions Analytics’ system utilises two-dimensional gas chromatography coupled with time-of-flight mass spectrometry to yield a unique and detailed chemical fingerprint for each tyre. The test method is designed to simulate the leaching of organic compounds over time from tyres and their wear products.

Research results show that certain product formulations lead to environmental impacts three times higher than alternative formulations. As a consequence, tyres not only vary significantly in wear rates, but also in chemical composition and environmental effects.

The aim of EQUA Tyre is to bring transparency to an area that has historically been under-researched, and which is now in the spotlight as a result of ever-heavier vehicles and rapidly cleaning tailpipes.

It’s an important time for vehicle emissions, the European Union is considering the potential new Euro 7 vehicle emissions regulation and whether to incorporate limits for non-exhaust emissions.

Emissions Analytics’ EQUA Tyre database is designed to give tyre OEMs and other suppliers, regulatory bodies and non-governmental interested parties access to a comprehensive, independent assessment of tyre composition.

This potentially points to the best ways to drive reductions in environmental and health impact through incentives to develop improved products. It also offers the opportunity to understand the sources of microplastics being observed in air, water and soil samples.

The resulting data is unique in the global tyre industry and the first major effort towards a comprehensive understanding of tyre composition affecting all matters, from tyre performance to environmental impact.

So while we may all be comfortable talking about vehicle emissions in terms of what comes out of the exhaust pipe, as regulations change, in the future we might have to start including data on tyres too.