Tyre Study

[Hollis Abdelkarim]

Createyour free account to receive personalised content alerts and Re:action, our weekly newsletter of the top chemical science stories handpicked from a range of magazines, journals and websites alongside insight and analysis from our expert editorial team.

Artificial turf containing crumb rubber from shredded tyres has become increasingly common on playgrounds and running tracks. Despite anecdotes about ill health caused by these surfaces, there has been relatively little investigation of them. Now, exposure of chicken embryos to water containing chemicals from crumb rubber reveals it is toxic to their early development, especially their brain and cardiovascular system.1

Schools, local authorities and sports organisations are replacing grass fields and playgrounds with artificial turf, as it is cheaper, saves water and is easier to maintain. There are already over 11,000 synthetic turf fields in the US and 13,000 in Europe.

Tyre crumb was soaked in water for a week, to simulate artificial turf exposed to rainfall, and then one of three treatments carried out: pipetting 1ml of leachate onto an egg, dipping an egg into leachate for 30 seconds or injecting 12l into the egg.

The effects were likely due to a complex mixture of chemicals leaching from the crumb rubber such as zinc, chromium, lead and arsenic. One particularly concerning chemical is benzothiazole, a potential mutagen and carcinogen.

Most toxicological experiments on crumb rubber have been performed on the tiny crustacean Daphnia and on algae. The effects on higher vertebrates, including humans, are unknown. Over 300 chemicals have been identified in crumb rubber, the paper notes, with 200 predicted to be cancer-causing and genotoxic.

Bridgestone in Europe, Russia, Middle East, India and Africa (BSEMIA), headquartered in Zaventem (Belgium), is a subsidiary of Bridgestone Corporation. In addition to its premium tyre products, BSEMIA offers a growing portfolio of tyre-centric and mobility solutions, and serves its customers in an extensive retail network with thousands of touchpoints.

Together with its partners and guided by its global corporate social responsibility commitment, Our Way to Serve, Bridgestone is dedicated to shaping a sustainable future of mobility and improving how people move, live, work and play.

According to the report, between 15 and 31% of the estimated 9.5 m tonnes of plastic released into the oceans each year could be primary microplastics, almost two-thirds of which come from the washing of synthetic textiles and the abrasion of tyres while driving.

In parts of the developed world enjoying effective waste management, such as North America, primary microplastics are a bigger source of marine plastic pollution than plastic waste, according to the report. Synthetic textiles are the main source of primary microplastics in Asia and tyres dominate in the Americas, Europe and Central Asia.

Recent calls to ban the use of microbeads in cosmetics are a welcome initiative, but as this source is only responsible for 2% of primary microplastics, the effects of a potential ban would be limited, the report states.

Plastic pollution harms marine wildlife and is thought to accumulate in the food web, with potentially negative consequences for human health. Effects on fragile ecosystems in regions such as the Arctic, where microplastics could affect ice formation and melting, are still unknown.

The site is secure.

The ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Air cavities in the tyre tread and the gap formed between tyre and pavement are excited during vehicle movement on a pavement. The former results in pipe resonance, and the latter results in horn resonance. These effects will be varying with speed of the vehicle and also because of conditions of tyre, pavement and, tyre-pavement interaction (TPI). The objective of this paper is to study the dynamic characteristics of air cavity resonances from the signals of the tyre-pavement interaction noise, which was collected by a pair of microphones, when a two wheeler is driven on a pavement at different speeds. The dynamic characteristics of the resonances are analysed using single frequency filtering (SFF) analysis of signals. The method gives spectral information at every sampling instant. The effects of impacts of the tyre treads, pavement characteristics, and TPI on the resulting cavity resonances are examined at four different vehicle speeds and for two different types of pavements. The analysis shows that the SFF spectra bring out the distinct characteristics of the pavements on the formation of air cavities and excitation of the resonances of these cavities. This analysis may help in determining the condition of the tyre and pavement.

The purpose of this study was to identify a characteristic elemental tyre fingerprint that can be utilised in atmospheric source apportionment calculations. Currently zinc is widely used as a single element tracer to quantify tyre wear, however several authors have highlighted issues with this approach. To overcome this, tyre rubber tread was digested and has been analysed for 25 elements by ICP-MS to generate a multielement profile. Additionally, to estimate the percentage of the tyre made up of inert fillers, thermogravimetric analysis was performed on a subset. Comparisons were made between passenger car and heavy goods vehicle tyre composition, and a subset of tyres had both tread and sidewall sampled for further comparison. 19 of the 25 elements were detected in the analysis. The mean mass fraction of zinc detected was 11.17 g/kg, consistent with previous estimates of 1% of the tyre mass. Aluminium, iron, and magnesium were found to be the next most abundant elements. Only one source profile for tyre wear exists in both the US and EU air pollution species profile databases, highlighting the need for more recent data with better coverage of tyre makes and models. This study provides data on new tyres which are currently operating on-road in Europe and is therefore relevant for ongoing atmospheric studies assessing the levels of tyre wear particles in urban areas.

Despite this, research on the environmental and health impacts of tyre wear has been neglected in comparison to the research and innovations dedicated to tackling fuel emissions. The Imperial researchers say that the effect of new technologies on the generation and impact of tyre wear should be a priority.

Electric vehicles are a crucial step forward to decarbonise transport, but we need to look at the big picture too. Some are concerned that electric vehicles tend to be heavier, which might increase tyre wear. This is exactly why Imperial College London is driving a holistic, joined-up approach to sustainability challenges.

As tyres break down they release a range of particles, from visible pieces of tyre rubber to nanoparticles. Large particles are carried from the road by rain into rivers, where they may leach toxic chemicals into the environment, whilst smaller particles become airborne and breathed in. They are small enough to reach into the deep lung.

While existing technological interventions, such as filters, and environmental policies could help to control our ecological footprint, there are huge gaps in our knowledge, understanding, and ability to forecast the impacts of tyre wear pollution.

There is emerging evidence that tyre wear particles and other particulate matter may contribute to a range of negative health impacts including heart, lung, developmental, reproductive, and cancer outcomes.

reductions in CO2 and other exhaust emissions. In tackling the climate crisis, we should design better systems and technologies to protect the environment; and research funding, government policy and regulatory frameworks should reflect this.

The report authors call for policymakers and scientists to investigate the complex problems related to tyre-wear pollution, from the basics of wear-particle production, to understanding how these particles affect the health of people and the planet. Potential innovation solutions include particle capture technologies, new advanced materials, and disruptive business models that encourage different transport choices. These need to be coupled to clear policy and regulation and to a broader discussion around urban transport systems.

Led by the University of Plymouth TYRE-LOSS brings together leading academics with the University of Exeter and Newcastle, Plymouth Marine Laboratory and an Advisory Group comprising 14 organisations including policy makers, tyre, automobile, plastics and water industries as well as academia and environmental charities.

This project builds on its predecessor, in which our researchers used an approach to demonstrate that substantial quantities of tyre particles are indeed entering the sea via storm water, waste water and from airborne dust. TYRE-LOSS will expand on this success to measure tyre particle concentrations at their points of entry to the marine environment and then describe their subsequent transport in the water column.

We will measure concentrations in the water, sediment and marine life at increasing distances from the places where these particles enter the sea and construct and validate mathematical models to describe the dispersal of tyre particles in inshore waters. This information will then be used establish the potential for any associated risks to marine life at environmentally relevant concentrations.

We provide the external portal to our extensive pool of world-leading experts and state-of-the-art facilities, enabling us to understand the relationship between the way we live, the seas that surround us and the development of sustainable policy solutions.

3a8082e126