TYRE DEBRIS IN AQUATIC ENVIRONMENT: THE NEW BLACK?

TYRE DEBRIS IN AQUATIC  ENVIRONMENT: THE NEW BLACK?

Recently, models on the fate of tyre wear particles (TWPs) have estimated that 18% of TWP emissions are transported from roads to freshwater bodies and approximately 2% are led out to estuaries and then marine habitats. What then happens to the remaining 16% of TWP emissions left in the freshwater compartment is not yet clear

 

Louise Lynn Halle is a PhD student in Environmental Biology
at Roskilde University, Department of Natural Science and Environment, Denmark,
with funds from Danish Environmental Analysis

The presence of tyre wear particles (TWP) in the aquatic environment is considered an emerging contaminant, and one that has gained increasing interest during the past few years. Although the presence of TWPs in the environment is given greater attention these days, TWPs have probably been present since the dawn of the pneumatic car tyre production in the late 19th century. The first scientific report of tyre dust identification along a roadside was published in 1961. Different perspectives have since been applied to this field of research and almost decade by decade shifted foci from degradation patterns to heavy metal release, to impacts of scrap tyres on the aquatic environment and leaching of chemicals from tyres. More recently, research within this field has been directed towards repurposing scenarios using crumb rubber in turf fields and playground material. Finally, in the 2010s, micronised tyre rubber has become grouped with other polymer debris and hence become part of the polymer landscape usually referred to as ‘microplastics.’ TWPs are considered to represent the majority of microplastics (or polymer debris) in the environment, and the newest calculation on the wear of tyres is estimated at 0.81 kg per person per year.

Now, looking at TWPs through the lens of microplastic pollution, research and information from the microplastics field are very well applicable to TWPs in many instances. With this new perspective of TWPs, increasing awareness of possible adverse effects in the environment follows - how do TWPs distribute in the different environmental compartments (soil, air, sediment, water and biota (living organisms)) and how do TWPs behave when exposed to different abiotic factors in these environmental compartments. For example, UV-radiation or pH, temperature and salinity differences could affect TWPs, but to what degree? A recent paper on this very subject concluded that particularly temperature and mechanical stress could influence the toxicity of TWPs. The focus of tyre production and function have seemingly always been directed towards maximising the three hallmarks: grip, wear and rolling resistance, and rightfully so, but somewhere along the road we forgot to consider where tyre abrasion actually disappears to. Luckily, some scientists already thought of this and today we can begin to lay the foundation to our collected TWP knowledge, based on the available scientific literature.

 

From roads to water

Research shows that the minority of TWPs end up in the airborne fraction (0.1-10%) and recently TRWPs have been assessed to contribute a low risk to human health in the particulate matter (PM) PM2.5 and PM10 range. So, where to find the remaining 90.0-99.9% of tyre debris emissions? Early research on particulate distribution showed a decreasing concentration of TWPs with increasing distance from the road. From there, TWPs are expected to wash off during rainfalls, transporting them to different environmental compartments. Recently, models on the fate of TWPs have estimated that 18% of TWP emissions are transported from roads to freshwater bodies and approximately 2% are led out to estuaries and then marine habitats. What then happens to the remaining 16% of TWP emissions left in the freshwater compartment is not yet clear and more research is needed to answer this question.

Aquatic organisms living in the water column or the sediment can interact with TWPs in their natural habitats during this particle transportation through freshwater to the marine environment. Although there are no scientific references on field observations of TWP ingestion by aquatic biota yet, few recent observations of this behaviour under controlled laboratory settings have been reported. In 2009 the first observation of the water flea, Daphnia magna, ingesting TWPs was described in the scientific literature and only two years ago the first photos were published showing ingestion of TWPs in the benthic amphipod Gammarus pulex following sediment exposure. Shortly thereafter photos of TWP ingestion in the amphipod Hyalella azteca and opossum shrimps from the mysidae family followed after water-only exposures, and most recently freshwater and marine fish species have been documented ingesting TWPs under laboratory conditions.

The recent focus on particulate effects of TWPs on biota is still in its infancy and the latest development in this field investigates the possible effects of both the particulate fraction and the leachate fraction. The leachate fraction is the suite of chemicals that leach out from TWPs to the surrounding water. Previously, tyre toxicity investigations in the aquatic environment revolved solely around the leachate fraction, which has been the primary focus over the last 30 years. Among the first papers the effect of whole tyre leachate was investigated showing worn tyre leachate to exhibit greater toxicity than leachate from a pristine tyre to rainbow trout. Furthermore, decreasing toxicity was observed with increasing salinity indicating that salinity either influences the leachability of toxic constituents or that an interaction of salts and toxic chemicals is present. Exposure of shredded tyre chips to different bacteria likewise showed a correlation between decreasing toxicity and increasing salinity, concluding that tyre leachate is likely to be a greater threat to freshwater habitats than to estuarine or marine habitats.

Toxicity pattern

Mysid after ingestion of TWPs (Private photo)

Further testing of TWPs and leachate on a freshwater species recently showed a dissimilar toxicity pattern when comparing acute toxicity responses of TWPs or leachate. Here, the amphipod H. azteca was exposed to either TWPs in freshwater or the leachate fraction alone, i.e. with no particulates present. This showed that leachate was more toxic in lower concentrations, presumably because dissolved chemicals are more bioavailable. Although, at higher concentrations, the particle fraction of TWPs became more toxic. This phenomenon very well describes the complexity and discrepancies when working with TWPs in the aquatic environment. It is not just a question of determining toxicity of a single chemical under controlled settings, but rather investigating a mixture of many chemicals in changing ambient environments. This complex matrix of polymer and chemicals can be more or less bound to the particle, which in itself might have adverse effects. However, the particle could also function as a vessel, containing chemicals and making them more or less bioavailable depending on the surrounding environment. Discovering exactly which chemicals leach out under different exposure scenarios, and most importantly, what of that is actually bioavailable to aquatic living species is the more interesting question to answer.

Due to the amorphous nature of rubber, end-of-life tyres (ELTs) have been used as leachate collection material and been used to collect polycyclic aromatic hydrocarbons (PAHs) and metals from contaminated waters. This discrepancy between the different TWP uses that in some cases could deem toxic and have adverse effects but at the same time might serve to mitigate other environmental issues is a great conflict of contradictory traits. Now, we need to unravel exactly when these contradictory traits are possibly affecting aquatic environments negatively and when these traits might be used for our advantage.

 

So how do scientists quantify TWPs and chemical constituents or ‘biomarkers’ from TWP leachate in water? The quick answer is that no tried and tested procedure is more right than any other now, we simply do not have conformity or guidelines on how to do this. Especially when looking to find particulates from tyre debris, as this is not usually detected when investigating for other polymer debris e.g. microplastics. Therefore, it is expected that the total amount of microplastics has been underestimated due to the lack of data from TWPs, which make up a large part of the estimated microplastic load worldwide and have not been reported on a regular basis. A multitude of methods have been used to estimate TWP emissions by measuring the concentration of chemicals in samples, with more or less success over the years. The biomarkers that have been used to determine TWP concentration most successfully include quantification of benzothiazoles and zinc. Both chemicals are used as part of the vulcanisation process and are also ubiquitous in nature. They are used for manufacturing of other materials, but specific versions can be attributed mainly to tyre manufacturing and are thus the most reliable compounds to measure.

How this emerging field of tyre ecotoxicology will progress ultimately depends on cooperation between different stakeholders having a common goal to pursue. The one thing that we can probably all agree on, is the need for tyres and other rubber products in our society. How we then fill that need, and what future decisions we make to maximise our understanding of the possible negative implications of TWPs in the aquatic environment is of paramount importance. Our job now is to continue our research within this field and ultimately prevent excess and unnecessary pollution of the water bodies that we all depend on, in a manner that stays true to both the environment and our need for safe and reliable tyres. 

*The author is a PhD student in Environmental Biology at Roskilde University, Department of Natural Science and Environment, Denmark, with funds from Danish Environmental Analysis

 

References

1.        Thompson. Identification of vehicle tyre rubber in roadway dust. Am Ind Hyg Assoc 27, 488–495 (1966).

2.        Lassen, C., Hansen, S.F., Magnusson, K., Norén, F., Hartmann, N.I.B., Jensen, P.R., Nielsen, T.G., Brinch, A. Microplastics - Occurence, effects and sources of releases to the environment in Denmark. (Danish EPA, 2015).

3.        Boucher, J. & Friot, D. Primary microplastics in the oceans: A global evaluation of sources. (2017). doi:10.2305/IUCN.CH.2017.01.en

4.        Kole, P. J., Löhr, A. J., Belleghem, F. G. A. J. Van & Ragas, A. M. J. Wear and tear of tyres : A stealthy source of microplastics in the environment. Int. J. Environ. Res. Public Health 14, 1265 (2017).

5.        Kolomijeca, A., Parrot, J., Khan, H., Shires, K., Clarence, S, Sullivan, C., Chibwe, L., Sinton, D., Rochman, C. Increased Temperature and Turbulence Alter the Effects of Leachates from Tyre Particles on Fathead Minnow (Pimephales promelas). Environ. Sci. Technol. 54, 1750–1759 (2020).

6.        Unice, K. M., Panko, J.M.., Chu, J. & Kreider, M. L. Measurement of airborne concentrations of tyre and road wear particles in urban and rural areas of France, Japan, and the United States. Atmos. Environ. 72, 192–199 (2013).

7.        Kreider, M. L., Unice, K. M. & Panko, J. M. Human health risk assessment of Tyre and Road Wear Particles (TRWP) in air. Hum. Ecol. Risk Assess. 0, 1–19 (2019).

8.        Unice, K. M. et al. Characterizing export of land-based microplastics to the estuary - Part I: Application of integrated geospatial microplastic transport models to assess tyre and road wear particles in the Seine watershed. Sci. Total Environ. 646, 1639–1649 (2019).

9.        Unice, K. M. et al. Characterizing export of land-based microplastics to the estuary - Part II: Sensitivity analysis of an integrated geospatial microplastic transport modeling assessment of tyre and road wear particles. Sci. Total Environ. 646, 1650–1659 (2019).

10.      Wik, A. & Dave, G. Occurrence and effects of tyre wear particles in the environment - A critical review and an initial risk assessment. Environ. Pollut. 157, 1–11 (2009).

11.      Redondo-Hasselerharm, P. E., de Ruijter, V. N., Mintenig, S. M., Verschoor, A. & Koelmans, A. A. Ingestion and chronic effects of car tyre tread particles on freshwater benthic macroinvertebrates. Environ. Sci. Technol. acs.est.8b05035 (2018). doi:10.1021/acs.est.8b05035

12.      Khan, F. R., Halle, L. L. & Palmqvist, A. Acute and long-term toxicity of micronized car tyre wear particles to Hyalella azteca. Aquat. Toxicol. 213, 105216 (2019).

13.      Halle, L. L., Palmqvist, A., Kampmann, K. & Khan, F. R. Ecotoxicology of micronized tyre rubber : Past , present and future considerations. Sci. Total Environ. 135694 (2019). doi:10.1016/j.scitotenv.2019.135694

14.      LaPlaca, S. B. & van den Hurk, P. Toxicological effects of micronized tyre crumb rubber on mummichog (Fundulus heteroclitus) and fathead minnow (Pimephales promelas). Ecotoxicology (2020). doi:10.1007/s10646-020-02210-7

15.      Kellough, R. M. The effects of scrap automobile tyres in water. (1991).

16.      Day, K. E., Holtze, K. E., Metcalfe-Smith, J. L., Bishop, C. T. & Dutka, B. J. Toxicity of leachate from automobile tyres to aquatic biota. Chemosphere 27, 665–675 (1993).

17.      Abernethy, S. The acute lethality to rainbow trout of water contaminated by an automobile tyre. (1994).

18.      Hartwell, S. I., Jordahl, D. M., Dawson, C. E. O. & Ives, A. S. Toxicity of scrap tyre leachates in estuarine salinities: Are tyres acceptable for artificial reefs? Trans. Am. Fish. Soc. 127, 796–806 (1998).

19.      Hartwell, S. I., Jordahl, D. M. & Dawson, C. E. O. The effect of salinity on tyre leachate toxicity. Water. Air. Soil Pollut. 121, 119–131 (2000).

20.      Gunasekara, A. S., Donovan, J. A. & Xing, B. Ground discarded tyres remove naphthalene, toluene, and mercury from water. Chemosphere 41, 1155–1160 (2000).

21.      Edil, T. B., Park, J. K. & Kim, J. Y. Effectiveness of scrap tyre chips as sorptive drainage material. J. Environ. Eng. 130, 824–831 (2004).

22.      Lisi, R. D., Park, J. K. & Stier, J. C. Mitigating nutrient leaching with a sub-surface drainage layer of granulated tyres. Waste Manag. 24, 831–839 (2004).

23.      Aydilek, A. H., Madden, E. T. & Demirkan, M. M. Field evaluation of a leachate collection system constructed with scrap tyres. J. Geotech. Geoenvironmental Eng. 132, 990–1000 (2006).

24.      Alamo-Nole, L. A., Perales-Perez, O. & Roman, F. R. Use of recycled tyres crumb rubber to remove organic contaminants from aqueous and gaseous phases. Desalin. Water Treat. 49, 296–306 (2012).

25.      Alamo-Nole, L. A., Perales-Perez, O. & Roman-Velazquez, F. R. Sorption study of toluene and xylene in aqueous solutions by recycled tyres crumb rubber. J. Hazard. Mater. 185, 107–111 (2011).

26.      Parker-Jurd, F. N. F. Napper, I. E. Abbott, G. D. Hann, S. Wright, S. L. Thompson, R. C. Investigating the sources and pathways of synthetic fibre and vehicle tyre wear contamination into the marine environment (project code ME5435). (2019).

27.      Kumata, H., Yamada, J., Masuda, K., Takada, H., Sato, Y., Sakurai, T., Fujiwara, K. Benzothiazolamines as tyre-derived molecular markers: Sorptive behavior in street runoff and application to source apportioning. Environ. Sci. Technol. 36, 702–708 (2002).

28.      Klöckner, P., Reemtsmp, T., Eisentraut, P., Braun, U., Ruhl, A.S., Wagner, S. Tyre and road wear particles in road environment – Quantification and assessment of particle dynamics by Zn determination after density separation. Chemosphere 222, 714–721 (2019).

Retreading In The Age Of EPR: Latin America Between Circular Ambition And Strategic Blind Spots

Tyre Recycling

As Extended Producer Responsibility (EPR) frameworks expand globally, the tyre industry is undergoing a structural transformation. Collection systems are improving, traceability is increasing and investments in recycling technologies are accelerating. However, one critical tension remains insufficiently addressed: the speed of industry evolution is outpacing the agility of public policy. And within that gap, one key question emerges: where does retreading fit in this new circular economy architecture?

A STRUCTURAL PARADOX

Retreading represents one of the most efficient forms of resource optimisation in the tyre lifecycle. It extends product life, reduces raw material consumption and lowers emissions. Yet, in many regulatory frameworks, it is still treated ambiguously – often grouped with recycling rather than recognised as prevention or preparation for reuse. This distinction is not semantic. It is strategic. Because when policy fails to differentiate, markets fail to prioritise.

A FAST-MOVING INDUSTRY, A SLOW-MOVING FRAMEWORK

The tyre market is evolving in real time:

  1. Increasing penetration of low-cost imports.
  2. Growing variability in product quality.
  3. Accelerated turnover cycles.

Retreading, in this context, becomes more than a circular solution. It becomes a filter of industrial quality. Not all tyres are equally retreadable. And that difference defines their real contribution to circularity. Yet most EPR systems continue to operate with uniform economic signals, failing to distinguish between products that enable multiple lifecycles and those that exit the system after a single use.

SIGNALS FROM EUROPE

Recent developments in countries like Portugal – where eco-fees applied to retreaded tyres approach those of low-cost, non-differentiated new tyres – highlight a concerning trend. Similarly, in Spain, industry representatives continue to advocate for a clearer institutional recognition of retreading within EPR systems. These cases illustrate a broader issue: circular policies can unintentionally undermine higher-value circular strategies.

THE MISSING LINK: PERFORMANCE-BASED POLICY

What is missing is not regulation. It is regulatory precision. EPR systems have successfully organised waste flows. But they have not yet evolved to reward performance within the lifecycle. This is where eco-modulation becomes critical.

ECO-MODULATION AS A STRATEGIC LEVER

Eco-modulation should not be a marginal adjustment. It should be a core industrial policy tool. Properly designed, it can:

  • Differentiate tyres based on real circular
  • performance.
  • Incentivise durability and retreadability.
  • Penalise short-lifecycle, non-recoverable products.
  • Align market behaviour with system objectives.
  • To operationalise this, we need new metrics.

FROM COMPLIANCE TO PERFORMANCE: A PROPOSED FRAMEWORK

The next step for EPR systems is to move towards performance-based differentiation. This could be implemented through instruments such as:

  • Retreadability Index (RI)
  • Performance Score (CPS)

These would measure:

  • Number of effective retreading cycles per tyre.
  • Structural durability and casing quality.
  • Real contribution to lifecycle extension.

Under such a system:

  • Tyres with higher retreadability would receive lower eco-fees.
  • Products that systematically fail to re-enter the cycle
  • would face higher costs.
  • This is not just a technical refinement. It is a shift from:
  • Generic compliance.
  • To intelligent market shaping.

THE LATIN AMERICAN PERSPECTIVE

In Latin America, the stakes are even higher.

The region faces:

  • Structural dependence on imported tyres.
  • Strong presence of low-cost, low-durability products.
  • Emerging EPR frameworks (Chile, Costa Rica, Peru, Ecuador)

Chile, for example, through its EPR law (Ley REP), has made significant progress in structuring collection and recovery targets. However, like many systems, it still faces the challenge of fully integrating reuse strategies into its economic logic. Under these conditions, retreading is not just an environmental solution. It is a strategic industrial capability.

BEYOND WASTE MANAGEMENT

Latin America has a unique opportunity to design EPR systems not only to manage waste

but to govern resources and shape markets.

This means:

  • Incentivising retreadable tyres
  • Strengthening local retreading industries
  • Reducing dependence on short-lifecycle imports
  • Building resilience into supply chains

But this requires something critical: policy agility. Because if regulation lags behind market dynamics, it will not transform the system – it will merely formalise its inefficiencies.

A STRATEGIC CONCLUSION

If EPR systems are designed without properly integrating retreading – and without differentiating based on actual circular performance – they risk reinforcing a linear logic under a circular narrative. For emerging regions, this would be a critical mistake

The discussion around repair, reuse and retreading can no longer be treated merely as a waste management issue. It is increasingly becoming a matter of industrial resilience, strategic autonomy and economic security.

As global supply chains face growing pressure from geopolitical fragmentation, logistics disruptions and volatility in raw material markets, extending the useful life of products is emerging as a strategic capability for nations and industries alike.

In this context, Right to Repair should not be understood only as a consumer right but also as an industrial policy tool capable of strengthening local economies, reducing external dependency, preserving technical capabilities and supporting more resilient production systems.

Retreading, remanufacturing and reuse are part of a broader transition where value creation is no longer based exclusively on extraction and disposal but increasingly on intelligence, efficiency and lifecycle management.

CIRCULARITY WITHOUT HIERARCHY BECOMES INEFFICIENCY. REGULATION WITHOUT DIFFERENTIATION BECOMES DISTORTION.

Final note

The future of the tyre industry will not be defined only by how we recycle, but by how intelligently we extend the life of what we already produce. And that requires alignment between:

  • Industry dynamics.
  • Policy design.
  • And strategic vision.

In that equation, retreading must move from the margins to the centre. Because properly understood, it is not just a process. It is a strategic filter, an industrial policy tool and a geopolitical lever.

ANRPC Publishes Monthly NR Statistical Report For May 2026

ANRPC Publishes Monthly NR Statistical Report For May 2026

The Association of Natural Rubber Producing Countries (ANRPC) has released its market report for May 2026, depicting a sector characterised by sustained price strength and firm fundamentals. The global natural rubber market received additional upward momentum from a decline in Brent crude oil prices, which averaged USD 107.14 per barrel during the month. This represented a month-on-month decrease of 8.65 percent, attributed to easing geopolitical tensions in the Middle East and the temporary reopening of the Strait of Hormuz, which collectively bolstered the commodity's outlook.

Global production projections for 2026 stand at 15.337 million tonnes, marking a 2.4 percent increase from the previous year, with growth driven by Thailand, China, India and Malaysia, even as output moderates in Indonesia and Vietnam. Monthly production, however, fell to 997,000 tonnes in May, a year-on-year decline of 4.7 percent, due to seasonal wintering and dry weather conditions across South and Southeast Asia. Concurrently, worldwide consumption is forecast to rise by 1.3 percent to 15.550 million tonnes for the year, with May's consumption reaching 1.310 million tonnes, a 4.6 percent annual increase. This demand was underpinned by steady tyre manufacturing, electric vehicle-related consumption and resilient purchasing managers' indices in China and India, alongside record auto retail sales in India.

Physical prices for all major grades recorded broad-based gains throughout May, with SMR-20, STR-20, RSS-3, RSS-4 and latex all experiencing increases. Trade flows showed a mixed pattern, as imports from China and India contracted month-on-month, while Malaysia and Vietnam registered significant gains. On the export front, Cambodia, Vietnam and Thailand recorded increases, whereas Indonesia and Malaysia saw declines. Currency movements saw the Malaysian ringgit ease slightly, while the Thai baht traded within a stable range, and both nations reported decelerating GDP growth for the first quarter of 2026. Futures contracts on the SHFE and SGX reflected tightening supply and firm demand, posting notable month-on-month gains.

The market outlook remains cautiously balanced against a backdrop of several macroeconomic factors. Elevated trade tensions between United States and China, ongoing geopolitical conflicts and a steady United States Federal Reserve interest rate policy present potential headwinds. However, these are being offset by supportive elements, including the accelerating adoption of electric vehicles, tight feedstock supply due to adverse weather and the positive market sentiment generated by the European Union's decision to lower anti-dumping duties on Chinese tyres.

Zeon Debuts Centralised Data Platform To Streamline Rubber Product Development

Zeon Debuts Centralised Data Platform To Streamline Rubber Product Development

Zeon Corporation has introduced a novel data management system specifically designed for elastomer research and development, marking the company’s first foray into a subscription-based service model. The platform is engineered to centralise and streamline R&D data pertaining to rubber products, with the primary goal of enhancing operational efficiency and accelerating developmental processes for its clientele. The initial phase of the rollout will concentrate on the Japanese market, with a strategic plan to broaden access to other regions in the future.

The elastomer industry frequently grapples with the fragmentation of data across disparate systems, which complicates the effective utilisation of historical information. Through extensive experience in elastomer supply and sustained client engagement, Zeon has identified this operational hurdle as a pervasive issue affecting the entire sector. This recognition has been the catalyst for developing a solution that directly confronts these data management deficiencies.

The newly launched system incorporates specialised functionalities that are finely attuned to the nuances of rubber product R&D. It integrates a comprehensive database that combines master data for key compounding agents available in Japan with extensive catalogue information, facilitating rapid and efficient data access for daily research tasks. The platform’s intuitive interface and user experience are meticulously crafted to optimise usability and data visualisation, with a commitment to ongoing enhancements based on evolving customer requirements.

Zeon has formally designated this data management solution as a growth driver for its strategic initiatives, extending beyond the Phase 3 objectives of its STAGE30 medium-term plan. The company envisions this business becoming a cornerstone of its strategy to augment the value proposition of its elastomer operations. By synergising its deep-seated elastomer expertise with advanced data utilisation technologies, Zeon is poised to foster innovation in client R&D and propel the overall advancement of the elastomer industry.

NaugaShield BIO-TR 30

NaugaShield BIO-TR 30

A new bio-based cut & chip resin for the most demanding applications.

NaugaShield BIO-TR 30 is SI Group’s latest advancement in bio-based performance resins designed to significantly improve cut and chip resistance in high-severity rubber applications. With approximately 75 percent bio-based content, this innovative material delivers on sustainability targets while exceeding the performance typically associated with petroleum-derived resins, making it a strong choice for applications such as OTR tyres in mining, construction and agriculture, mining conveyor belts, rubber tracks and mill linings.

Cut and chip resistance is a complex set of material behaviours, including static mechanical strength, dynamic response under deformation and ability to withstand sharp impacts and abrasive environments. In demanding applications such as mining or agriculture, materials must tolerate repeated high-strain loading and resist the initiation and propagation of tears. NaugaShield™ BIO-TR 30 was developed precisely to meet these conditions, demonstrating notably low dynamic heat buildup and excellent tear strength – characteristics closely tied to enhanced cut and chip resistance and long-term durability under cyclical loads.

To evaluate its performance, NaugaShield BIO-TR 30 was benchmarked in an Off-road Rib Tread formulation against two widely used industry references: a gum rosin/semi-aromatic C5/C9 resin combination and a styrenated DCPD resin. All materials were tested at an equal loading of 10 phr to provide a direct and unbiased comparison. Under these conditions, the bio-based resin consistently outperformed both alternatives, offering a stronger balance of reinforcing behaviour, improved tear propagation resistance and superior resistance to thermal degradation during dynamic flexing. Further improvements were achievable by reducing the amount of free extender oil in the compound, underscoring the resin’s adaptability in formulation design and its ability to unlock even greater performance when optimised.

These laboratory indicators were corroborated through extended Coesfeld Cut & Chip testing (see chart), in which compounds were subjected to up to 3,000 cycles at 200 rpm under a 200N applied force. Formulations containing NaugaShield BIO-TR 30 exhibited substantially lower mass loss and maintained tread surface integrity more effectively than the hydrocarbon and gum rosin-based-benchmarks. The performance advantage was even more pronounced in compounds adjusted for lower free oil content, confirming that the resin can be tailored to meet the durability requirements of the most challenging operating conditions.

The strong performance of NaugaShield BIO-TR 30 in OTR tread compounds can be readily transferred to other rubber goods that encounter similar wear mechanisms. Applications such as mining belts, agricultural and construction tracks or mill linings benefit from the resin’s ability to reinforce the rubber matrix, reduce crack growth under repeated impact and maintain structural cohesion under high-strain deformation. This versatility allows manufacturers to integrate a 75 percent bio-based resin that supports sustainability by reducing fossil-based content and helping end products last longer while maintaining – and often improving – operational performance across multiple product lines.

NaugaShield BIO-TR 30 is currently available in commercial quantities, enabling compounders and manufacturers to move directly from laboratory evaluation to pilot- and production-scale trials.