It was recently discovered additives in tyres are toxic to aquatic organisms, after causing a series of mass salmon deaths in the US state of Seattle. The compounds were washed off the roads and into waterways during heavy rainfall and storms.
Thus, a new project, a collaboration between the University of Portsmouth and the Emissions Analytics Ltd, aims to determine the concentrations of additives in UK aquatic environments, as well as the varying toxicity of car tyre particles from different tyre manufacturers.
Vehicle tyre wear is also predicted to rise with the increase in battery electric vehicles (BEVs), which are heavier, causing an increased risk to river and coastal environments.
Project lead, Professor Alex Ford, from the University of Portsmouth’s School of Biological Sciences, said: “The chemical composition of car tyres differ dramatically between manufacturers. We want to find out which models pose the most significant threat to river and coastal environments.”
Environmental sampling has been conducted within Langstone Harbour on the south coast of England, close to road run-off points from the busy M27 motorway.
The coastal area is a marine habitat, Site of Special Scientific Interest (SSSI), special area of conservation (SAC) and internal RAMSAR wetlands that is designated site for its visiting bird species.
By comparing environmental data with Emissions Analytics unique databases, so far the team has established 154 chemical additives in seaweeds and 105 in sediments which can also be found in car tyres.
“The M27 is known to carry 140,000 cars and lorries every day, so it is likely to be a heavy source of car tyre contamination to this protected environment,” explained Henry Obanya who has been conducting the research for his PhD.
“Langstone Harbour contains significant seagrass, saltmarsh and oyster reefs, making it an important nursery for many fish species and seal populations. The next step is to go through the compounds we identified one by one, and determine whether they could be unique to car tyres or could be potentially explained by other sources of contaminants to the harbour.”
Emissions Analytics is an independent firm measuring real-world emissions, working on applications ranging from cars to marine vessels.
Over the past few years the company has been testing and analysing tyre wear emissions across a wider range of driving conditions, and has performed a detailed chemical analysis of hundreds of new tyres. The findings revealed emissions from tyre wear is around 1,850 times greater than tailpipe emissions.
Nick Molden, Emissions Analytics CEO, said: “We know that the levels of tyre emissions is significant, but what we don’t know enough about yet is how the chemicals that also come off tyres are affecting the environment.
“We’re confident the team at the University of Portsmouth can help fill in the gaps, and provide us with a clearer understanding of the impact these compounds are having, both on marine life, and also our own.”
Professor Ford’s previous research at the University of Portsmouth’s Institute of Marine Sciences revealed tiny quantities of antidepressants in water can affect wildlife, such as crustaceans and molluscs. It also found drugs will affect the behaviour and biological make-up of these creatures, including changing colour, growth and reproducing less or more.
He added: “Unfortunately, like many urbanised coastlines the harbour suffers from many human pressures including sewage discharges, farm and urban run-off plus seepages from historic coastal landfills. It’s important to understand the impacts each of these pressures are having on our coastal ecosystems if we are to move forward as a society and live more sustainably and protect those habitats which are so important to our own health.”