Vehicle-related particulate matter (PM) emissions may arise from both exhaust and non-exhaust mechanisms, such as brake wear, tyre wear, and road pavement abrasion, each of which may be emitted directly and indirectly through resuspension of settled road dust. Several researchers have indicated that the proportion of PM2.5 attributable to vehicle traffic will increasingly come from non-exhaust sources. Currently, very little empirical data is available to characterise tyre and road wear particles (TRWP) in the PM2.5 fraction. As such, this study was undertaken to quantify TRWP in PM2.5 at roadside locations in urban centres including London, Tokyo and Los Angeles, where vehicle traffic is an important contributor to ambient air PM.

The sources of PM2.5 vary spatially with long-range transport sources generated mainly from secondary PM and local sources generated mainly from combustion processes associated with industrial operations and road transport. A recent literature review of various PM2.5 local source apportionment studies conducted in 51 different countries concluded that 25% of urban ambient air pollution from PM2.5 is contributed by traffic, 15% by industrial activities, 20% by domestic fuel burning, 22% from unspecified sources of human origin, and 18% from natural dust and salt. Both primary and secondary PM were accounted for in the analysis and the contribution was dependent on the source. For example, the researchers generally apportioned traffic sources by primary PM emissions and the unspecified sources of human origin based on secondary PM emissions. PM2.5 also varies spatially and temporally.

Over the last 20 years, environmental agencies worldwide have enacted regulations, including those for motor vehicles, in an effort to reduce the emissions of PM2.5; and, indeed, a decline is observable in areas with established monitoring networks. For example, in the US, from 2000 to 2016, the nationwide levels of PM2.5 have decreased 42%; with the vast majority of the measurements below the national standard of 12 μg/m3 since 2012. In Europe (EU-28), the emissions of primary PM2.5 decreased by 16% from 2003–2012.

Vehicle-related PM emissions may arise from both exhaust and non-exhaust mechanisms, such as brake wear, tyre wear, and road pavement abrasion. Several researchers have indicated that the proportion of vehicle traffic attributable to PM2.5 will come increasingly from non-exhaust sources, due to additional regulations limiting vehicle exhaust emissions. The current and future contributions of non-exhaust sources have been evaluated primarily through indirect methods such as various receptor-modelling approaches or air dispersion modelling paired with emission inventories. A recent literature review of non-exhaust emissions reported more than 250 estimates of contribution to ambient air PM.

When tyres interact with the roadway surface, tyre and road wear particles (TRWP) are produced, containing both the tread rubber and embedded road material.

The contribution of tyre wear to ambient PM10 and PM2.5 has been estimated to be between 0.8–8.5% and 1–10% by mass respectively, although the data are sparse and most estimates are indirectly calculated with only a few observational studies. Given the complex composition of the TRWP, a variety of analytical techniques have been proposed, but the only ones with sufficient specificity to the particles are chemical markers associated with the tread rubber, which include monomers styrene and 1,3-butadiene, as well as the dimers vinylcyclohexene and dipentene. Given the predicted increases in non-exhaust emission contributions to PM2.5, the current study was undertaken to measure levels of TRWP in PM2.5 in urban environments where traffic-related PM is significant. Sample locations were chosen to be representative of likely human exposure in various roadside microenvironments. To facilitate comparison to our earlier work and estimates published by others, we present mass-based concentrations and relative contribution to PM2.5 for both TRWP and tread for each sampling location.

Materials, methods

To select the cities for inclusion in this study, data were assembled for large urban areas in Europe, Asia, and the United States. A selection matrix was developed to identify cities based on several criteria including, levels of ambient PM2.5, traffic loads, population density, and local regulatory actions to reduce PM2.5.

In Europe, five cities were considered, including Barcelona, London, Milan, Paris and Rome, with London being ultimately selected. In Japan, six cities were considered, including Nagoya, Osaka, Tokyo, Saitama City, Yokohama, and Kyoto, with Tokyo being ultimately selected. In the US, three cities were considered, including Atlanta, Los Angeles and New York City, with Los Angeles ultimately selected.

Within each city, the site selection criteria included the presence of identifiable traffic and historical presence of high PM2.5 levels where possible. All air samples were collected near the roadside, and the distance from road was dictated by logistical constraints such as security of the equipment and available power sources. For London only, an urban background site was also included.

The analytical technique is based on the characteristic fragments generated by the thermal decomposition of the tyre tread polymers that include styrene butadiene rubber (SBR), butadiene rubber (BR) and natural rubber (NR). Briefly, the method consists of the following steps: the tread rubber polymers in environmental samples undergo thermal decomposition at 670 °C by Curie-point pyrolysis; next, the thermal decomposition products are separated using a gas chromatograph (GC); and finally, the pyrolysis fragments are quantified with mass spectrometry (MS).

The data were evaluated using the Analysis of Variance (ANOVA) and regression models to identify differences among the cities and trends in determinants of TRWP concentrations between sampling locations and cities.

Results

In total 80 samples were analysed, and the TRWP detection frequencies ranged from 0–100%. The lowest detection frequencies were recorded in Los Angeles, with four of the six locations showing no detections. The total ambient PM2.5 levels were low in Los Angeles during sampling days, which was surprising due to the historical levels recorded in the area for the same time of year.

The TRWP made a small contribution to total ambient PM2.5 levels, representing 0.1–0.68% of the total PM2.5 across all locations. The range of concentrations of TRWP were 0.012–0.29 μg/m3 in London, 0.010–0.1 μg/m3 in Tokyo, and 0.004–0.072 μg/m3 in Los Angeles. The highest concentrations were recorded at the Blackwall Tunnel Approach in London (mean 0.104 μg/m3 and range (0.03–0.29 μg/m3)) where significant braking activity occurs before the tunnel portal which creates more tyre wear abrasion than constant speed driving.

The highest TRWP PM2.5 concentration measured in Tokyo was at the Kawasaki Industrial Road location, which had the highest traffic count of the Tokyo sites. In both Tokyo and London, the traffic composition was dominated primarily by passenger car and light duty vehicle traffic, with truck traffic generally comprising less than 20% of the total traffic. One exception was Kawaskai Industrial Road, where the truck traffic accounted for nearly 43% of the traffic.

Uncertainties

The data generated from this research provide an initial observation of TRWP in PM2.5 using methods that are specific to tyre tread, however, they are site specific and may not be applicable more broadly given the small sample size and consequent low statistical power. The calculation of the TRWP concentration involves the assumption of 50% of the polymer in the tread and 50% of tread in the TRWP. However, the 50% assumption of tread in the TRWP is based on the characterisation of bulk TRWP in the size range of 0–150 μm. As such, the composition of the <10 μm fraction has not been specifically characterized.

It is currently unknown if the use of the 50% tread assumption overestimates or underestimates that composition in the <10 μm particles. Previously, the tyre wear contribution to the PM2.5 fraction was evaluated using Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) and the researchers concluded that there was both a pavement and tread component, although the researchers did not have a quantitative estimate of the amounts. More recently, roadside airborne particulate in the 10–80 μm range was characterised using SEM EDX and the researchers concluded that the amount of pavement encrustation of the surface area of the ‘tyre core’ (i.e., tread) ranged from approximately 10% to more than 50%. As such, more research may be needed to refine TRWP composition in the PM10 and PM2.5 fractions.

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Michelin has announced a strategic collaboration with BLAST, the organiser behind the 2026 Rocket League Championship Series (RLCS), which serves as the premier global tournament for the popular video game Rocket League. Through this agreement, Michelin becomes an official partner of one of the most energetic and widely viewed eSports properties on the international stage.

Rocket League itself enjoys immense global popularity, attracting several million active participants on a monthly basis. The RLCS season consistently draws tens of millions of views across the world, underscoring its significant reach. This move allows Michelin to deepen its involvement in the competitive gaming sector by associating with a high-profile series known for its passionate following.

The game’s core dynamic involves vehicles competing in a fast-paced arena where precision, control and rapid execution are paramount. These very attributes closely align with Michelin’s established heritage in mobility solutions and high-performance engineering, particularly its extensive background in motorsport. The partnership therefore represents a natural extension of the brand’s core principles into a digital environment.

By entering the world of the RLCS, Michelin seeks to enhance its connection with younger demographics and solidify its relevance within the digital spaces that are increasingly defining future trends and cultural habits. This initiative builds on a foundation of over 25 years during which Michelin has cultivated partnerships within the gaming and automotive simulation spheres, consistently applying its technological know-how to support both realism and superior performance in virtual driving experiences.

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The Yokohama Rubber Co., Ltd., has entered into a new agreement to serve as the official tyre supplier for BMW M Motorsport, the division responsible for the brand's global racing endeavours. This collaboration will debut at the prestigious Nürburgring 24-Hour Race and throughout the Nürburgring Langstrecken-Serie in 2026.

This renewed partnership revives a historical connection between the two companies, who previously worked together on the same iconic circuit from 1980 to 1990. During that initial decade-long stint, their combined efforts secured two overall victories. After an interval of nearly four decades, they are reuniting for the current season to compete in the premier SP9 class, fielding the BMW M4 GT3 EVO. For this campaign, Yokohama will equip the vehicle with its high-performance ADVAN racing tyres, with the shared objective of capturing another overall win.

Beyond its tie-up with the BMW team, Yokohama Rubber continues its longstanding commitment to the Nürburgring. It will provide its tyres to numerous leading teams contesting both the endurance series and the 24-hour event this season. The company is focused on achieving an overall championship victory for a vehicle equipped with its YOKOHAMA brand tyres.

Franciscus Van Meel, CEO, BMW M GmbH, said, “We are excited to welcome YOKOHAMA as Official Partner of BMW M Motorsport for our Nürburgring programme. YOKOHAMA’s technical expertise and motorsport passion strengthen our drive for maximum performance and precision. Their support allows our team to focus fully on what defines BMW M Motorsport: pushing the limits on every lap. We look forward to a strong endurance season.”

Team: Schubert Motorsport
Class: SP9
Car: BMW M4 GT3 EVO
Tyres:
ADVAN A005 (for dry conditions); Sizes: front 300/680R18, rear 330/710R18
ADVAN A006 (for wet conditions); Sizes: front 300/680R18, rear 320/710R18

Race Schedule (as of date of this release)
March 14 (Sat): NLS Round 1
March 21 (Sat): NLS Round 2
April 11 (Sat): NLS Round 3
April 18 (Sat) –19 (Sun): Nürburgring 24-Hour Race (Qualifiers) , NLS Rounds 4 & 5
May 14 (Thu) –17 (Sun): Nürburgring 24-Hour Race
June 20 (Sat): NLS Round 6
August 1 (Sat): NLS Round 7
September 12 (Sat) –13 (Sun): NLS Rounds 8 & 9
October 10 (Sat): NLS Round 10

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Hankook Tire has introduced the Laufenn X FIT AT2, a new addition to its all-terrain tyre lineup aimed at drivers who require durability and adaptability without compromising on everyday driving comfort. Positioned as an affordable option, this tyre is engineered to handle a mix of on-road and off-road conditions while delivering long-lasting value.

Building upon the foundation of its predecessor, the X FIT AT2 brings several performance upgrades. It features enhanced traction across varied landscapes, a 15 percent improvement in tread longevity and reliable handling in different weather conditions. The tyre is designed to fit a broad spectrum of light trucks and SUVs, with availability ranging from 15 to 22 inches to accommodate popular vehicle models in the market.

This launch reflects Laufenn’s ongoing strategy to diversify its offerings as it strengthens its presence in over 100 countries. Since its introduction in Europe, the brand has consistently expanded its range for both passenger vehicles and commercial applications, responding to shifting consumer needs. The X FIT AT2 reinforces this direction by providing a balance of rugged capability and composed road manners for those who frequently transition between highways and rougher terrain.

Engineered for resilience, the tyre incorporates a reinforced structure, including select sizes with three-ply sidewalls to resist cuts and impacts. Its tread design features directional and lateral grooves that enhance water dispersion and grip on slippery or loose surfaces. Additional protective elements such as offset shoulder blocks and rim guards help shield against debris and curb damage. A two-step deep sipe pattern promotes uniform wear, contributing to extended usability.

Certified with the Three-Peak Mountain Snowflake symbol, the X FIT AT2 offers dependable performance in dry, wet and snowy winter conditions. It comes with warranty coverage tailored to its sizing, offering 60,000 miles for P-metric versions and 50,000 miles for LT-metric options. With this release, Laufenn continues to round out its portfolio alongside existing lines such as the S FIT, G FIT and I FIT series.

KC Jensen, Vice President – U.S. Passenger Car and Light Truck Sales, Hankook Tire America Corp, said, “The X FIT AT2 represents the next step forward for the Laufenn brand as we continue to deliver practical, dependable solutions for everyday drivers who also want the freedom to explore off-road. Building on the success of the original X FIT AT, this second-generation tyre offers a stronger blend of durability, versatility and everyday comfort at an accessible value.”

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Comerio Ercole is set to make a significant impact on the global stage in 2026 with its participation in two major industry exhibitions. The company will showcase its latest advancements at both Chinaplas 2026 and Tire Technology Expo 2026, highlighting a comprehensive portfolio designed to enhance precision, productivity and sustainability in polymer processing.

At Tire Technology Expo, Comerio Ercole will present integrated systems tailored for the tyre industry, focusing on high-performance rubber calendering and digital intelligence. A flagship solution is the TRIPLE 4-roll calendering unit. Its innovative "S" configuration provides remarkable flexibility by enabling the processing of both textile and steel cord, as well as the production of rubber sheeting, all within a single line. The system’s capability for simultaneous lamination ensures high precision and product stability while minimising defects. Downtime is a critical factor in tyre production, and the patented FASTEEL system directly addresses this. By automating the steel cord change process, it dramatically reduces changeover time from hours to minutes, allowing the line to continue running during preparation and thereby maximising plant availability and operator safety. Following the calendering process, the SUPERCUT system guarantees clean, precise transversal cuts for both steel and textile-reinforced rubber, integrating guillotine and high-speed rotary blades to minimise waste and streamline downstream winding.

Simultaneously, at Chinaplas 2026, taking place in Hall 2.1 at Stand C85, the company will place a strong emphasis on its patented HYDROPLUS concept for PVC and plastic calendering. This technology suite is engineered to deliver micrometric precision and robust process stability through advanced hydraulic controls. Central to this is HYDROGAP, a system that achieves exceptional thickness uniformity with high-resolution gap positioning. Complementing this are HYDROSAFE, which ensures rapid roll separation for ultimate protection, and HYDROTHERM, a feature that intelligently compensates for thermal expansion to maintain precise gap settings during fluctuating operational temperatures.

Beyond mechanical innovation, the company is driving digital transformation with its CELEMETRY and MINERV-AI platforms. CELEMETRY focuses on sustainability by converting production data into actionable insights for environmental reporting and energy optimisation. MINERV-AI captures and standardises operational expertise through artificial intelligence, supporting more effective maintenance protocols, training procedures and overall operational consistency. Through these combined efforts at both exhibitions, Comerio Ercole is demonstrating a holistic approach to advancing the plastics, rubber and tyre industries.

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