Citizen science reveals microplastic hotspots within tidal estuaries and the remote Scilly Islands, United Kingdom

• Published in: Marine pollution bulletin Vol. 161; no. Pt B; p. 111776
• Main Authors: Nel, Holly A., Sambrook Smith, Gregory H., Harmer, Rogan, Sykes, Rebecca, Schneidewind, Uwe, Lynch, Iseult, Krause, Stefan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2020; Elsevier BV
• Subjects: Accumulation zone; Brackishwater environment; Case studies; Citizen Science; Distribution; England; English Channel; Environmental Monitoring; Estuaries; Geologic Sediments; Hot spots; Intertidal; Island beaches; Islands; Microplastics; Mitigation; Nile red; Plastics; Polyethylene; Polyethylenes; Polypropylene; Population density; Sediment; Spatial discrimination; Spatial resolution; United Kingdom; Water Pollutants, Chemical - analysis; England; United Kingdom; United Kingdom > UK; English Channel; Nile red; Accumulation zone; Island beaches; Intertidal
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2020.111776

The identification of microplastic hotspots is vital to our long-term understanding of their environmental fate and distribution. Although case studies have increased globally, sampling campaigns are often restricted geographically, with poor spatial resolution. Here, we use citizen science to increase our geographical reach, which improved our understanding of microplastic distribution in estuarine and beach sediment along the south-west coast of England. Hotspots (>700 particles per kg dry sediment) were identified on the Scilly Islands and in close proximity to major metropolitan hubs (i.e. Falmouth and Plymouth). Particles extracted from the Scilly Island sites were composed of polyethylene and polypropylene. With low population density on the Isle of Scilly, hotspots may suggest that microplastics originate from distant sources, while Falmouth and Plymouth, on mainland UK, are locally supplied. This information supports the design of future campaigns and targeted mitigation strategies in areas of highest concentrations. [Display omitted] •Hotspots (>700 particles per kg dry sediment) were detected on the Scilly Islands.•Microplastic hotspots were also associated with major metropolitan hubs.•Distant and local sources were discussed.