Microplastics in Exeter waters found to carry superbugs and antibiotic-resistant bacteria

A University of Exeter-led study has found that microplastics in rivers and coastal waters can carry harmful bacteria and antimicrobial resistance genes, highlighting potential risks to public health and the environment in Exeter and across Devon.

The research, conducted in partnership with Plymouth Marine Laboratory, analysed microplastics collected from waterways influenced by hospital and domestic wastewater. 

The team tested five substrates, including bio-beads used in UK wastewater treatment, nurdles (plastic pellets used in manufacturing), polystyrene, wood, and glass. 

After two months in the water, microbial biofilms on each surface were examined using genomic analysis.

Microplastics are already widely found in the UK’s rivers, lakes, soils, oceans, and even within human tissue. 

READ NEXT: Mallison Bridge replacement scrapped as costs soar beyond £1m budget

The researchers call for stricter monitoring of high-risk plastics like bio-beads and nurdles, improved waste management, and further studies on how plastics interact with other pollutants.

Results showed all plastic types harboured pathogenic bacteria and antimicrobial resistance genes (ARGs), with polystyrene and nurdles particularly prone to supporting these microbes. 

Over 100 unique ARG sequences were identified, including resistance to key antibiotics such as aminoglycosides, macrolides, and tetracyclines. 

Some pathogens were found to increase downstream, suggesting that microplastics can transport harmful bacteria from wastewater sites to rivers, beaches, and shellfish areas used by local communities.

Dr Emily Stevenson, lead author and researcher at the University of Exeter, said: “Our study shows that microplastics can carry pathogens and antibiotic-resistant bacteria over long distances.”

“For Exeter residents who enjoy the River Exe, local beaches, and coastal activities, this highlights the importance of safe handling of plastics and proper hygiene during beach cleans or river-based recreation.”

Professor Pennie Lindeque of Plymouth Marine Laboratory added: “Microplastics act like tiny vehicles for bacteria. They can affect recreational sites, aquaculture, and marine wildlife—making it both an environmental and public health concern for Devon.”

Dr Aimee Murray, Senior Lecturer in Microbiology at the University of Exeter, emphasised the broader implications: “Microplastics are not only a pollution problem—they may facilitate the spread of antimicrobial resistance. Integrated strategies are needed to manage plastic waste and protect both human and environmental health locally.”

The study also recommends precautions for local community clean-up efforts, including the popular beach cleans around Exmouth, Topsham, and Dawlish, advising volunteers to wear gloves and wash hands thoroughly to reduce exposure to potential pathogens.