From road to sea: Exploring the biological effects of tyre particles in marine invertebrates. (Ref:4293)

Project Background: Tyre wear particles are anthropogenic particulates that stem from the abrasion of synthetic rubber tyres on road surfaces. It is estimated that over 3.4 million tonnes of tyre wear particles are released globally each year. These particles can become airborne or enter highway drainage systems, often resulting in their

deposition within the natural marine environment. Tyres contain high concentrations of labile additives, including zinc oxide, antioxidants and plasticizers, that have proven toxic in leachate studies, however the

risk posed by tyre particulates themselves is less evident, nor is it clear whether "greener" iterations of tyres may prove any less toxic to aquatic biota. Project Aims and Methods: In this PhD, you will undertake pioneering ecotoxicological research to explore the mechanisms underpinning

tyre particle toxicity, with a view to identifying greener, safer-by-design options for tyres. The planned work aims to improve our predictions of the risks posed by tyre wear particles, with wider relevance for understanding the fundamental ways in which anthropogenic stressors affect organisms. The PhD will

address the overarching research question of "What are the physico-chemical drivers of tyre particle toxicity and might alternative tyre compositions prove less toxic?". Across the project, you will work with the supervisory team to co-develop ecotoxicological studies to evaluate the relative toxicity of different tyre

particles, including "greener" variants. Exposure studies will use representative, fully-characterised tyre wear particles, in combination with ecologically important marine invertebrates, such as the pelagic copepod Calanus helgolandicus and the epibenthic mussel Mytilus edulis.

You will consider the adverse risk of tyreparticles and tyre leachates on a range of biomarkers across the biological hierarchy (e.g. immune response, reproductive endpoints) to elucidate potential modes of action and adverse outcome pathways. Latterly, a targeted, chemical-by-chemical approach can be used to compare the toxicity of "high risk" additives with potential alternatives, paving the way for a lower risk chemical future for the tyre industry.