Rapid ‘fingerprinting’ of potential sources of plastics in river systems: an example from the River Wye, UK

ABSTRACT

Literature review identified seven principal pathways of plastic debris entry into river systems: waste water treatment plants; combined sewer overflows; on-site wastewater treatment systems; road and rail transport systems; agriculture; industrial sources; and diffuse litter. A further category of ‘microplastics’ reflects their multiple potential sources, including microplastic breakdown within rivers. Regulatory and management bodies necessarily make operational decisions based on resource limitations and significant uncertainty due to sparse or missing data, requiring a substantial degree of inference. To support this need, we develop a rapid, desk-based approach based on risk criteria to ‘fingerprint’ likely pathways of plastic pollution based on catchment characteristics. Characteristics of the River Wye system in the UK are reviewed identifying a risk-based ‘fingerprint’ of potential pathways of plastic entry or accumulation of plastic debris, represented graphically as a colour-coded ‘traffic lights’ classification. This ‘fingerprinting’ approach is based on desk-based inference from published materials as a rapid and resource-efficient alternative to intensive data collection, supporting prioritization of further investigation or response measures. We recommend replication of this ‘fingerprinting’ approach in other river catchments to support operational management of plastic pollution. Where feasible, it may also be down-scaled where sub-catchment or major river reach properties differ significantly.

HIGHLIGHTS

• Unique catchment characteristics influence likely sources of plastics in rivers

• Seven potential plastic sources were identified, with a residual microplastics category

• Literature, interviews and surveys can rapidly ‘fingerprint’ likely plastic sources

• Fingerprinting can prioritize management and investigations in specific catchments

KEYWORDS:

• Macroplastic
• microplastic
• river Wye
• fingerprinting
• management response options
• risk-based

Acknowledgements

The authors are grateful for co-funding by the International Water Security Network, which is funded by Lloyd’s Register Foundation, a charitable foundation helping to protect life and property by supporting engineering-related education, public engagement and the application of research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Funding from the International Water Security Network, which is funded by Lloyd's Register Foundation, a charitable foundation helping to protect life and property by supporting engineering-related education, public engagement and the application of research.