Primary Supervisor:
Stephen Sturzenbaum
Division of Analytical, Environmental & Forensic Sciences, KCL
Secondary Supervisor:
Stephanie Wright
Division of Analytical, Environmental & Forensic Sciences, KCL
Project Description:
Microplastics vary in type, shape, size and (biological and chemical) load and soil acts as a microplastic sink due to the degradation and deposition of airborne microplastics. Consequently, terrestrial organisms may be at risk and solutions-based research is needed. On the flip side, polymeric materials can be fabricated from bio-renewable resources, so called bio-plastics. Such bio-based substitutes are often inherently biodegradable and present a promising avenue to reduce the flow of solid plastic waste into municipal landfill by diverting it to composting facilities. This is potentially safer and possibly even beneficial should such systems leak, as well as opening up the possibility of ‘reusing’ the carbon in the plastic as compost. Once degraded, the by-products of the decomposition from plastic to microplastic has unexplored potential as an energy source, which could be assimilated by soil-based organisms. Earthworms are able to degrade both macro- and micro-sized organic matter, thus may be able to harness energy and / or substrates from bio-based microplastics, transforming them further to other decomposition products. Work on enhancing the natural capacity or earthworms to contribute towards the bio-remediation of compost and soil contaminated with microplastics is an unexplored area of potentially high impact biotechnological research, a shortfall this project aims to redress. Taken together, the approaches will provide a mechanistic understanding of the interplay between earthworms, its local microbiome and microplastic degradation. Most importantly, this project seeks to pioneer approaches that will accelerate microplastic degradation and in doing so will offer solutions to the plastic waste crisis.
Policy Impact of Research:
The work will help to develop risk assessment strategies for microplastics in soil environments. It will support DEFRA’s consultations and legislation banning microbeads for environmental protection. It will also support the European Commission’s recommendations to minimise microplastic release to the environment.
