The fate and persistence of microplastics and associated pathogens in lowland rivers

Project Information

MICROPATH

Grant agreement ID: 833702

DOI

10.3030/833702

Project closed

EC signature date 10 April 2019

Start date 1 January 2021

End date 31 December 2022

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 224 933,76

EU contribution

€ 224 933,76

Coordinated by

THE UNIVERSITY OF BIRMINGHAM
United Kingdom

Periodic Reporting for period 1 - MICROPATH (The fate and persistence of microplastics and associated pathogens in lowland rivers)

Reporting period: 2021-01-01 to 2022-12-31

Summary of the context and overall objectives of the project

Global plastic production exceeds 300 million tons per year and wastewater treatment plants release over 4 million microplastics, defined as between 1μm to 5 mm in diameter, per day to streams. Since microplastics act as a substrate for microorganisms, pathogenic bacteria can more easily transport downstream using microplastics as a vector. Furthermore, microplastics deposit and accumulate within stream transient storage areas such as streambed sediments, where previous studies on fine particles in the same size range as microplastics have shown persistence within these stream transient storage areas for months to years. Thus, plastic and fecal pollution sourced from point and non-point sources can increase both the public health risk via disease transmission and the impairment of the ecological quality of aquatic systems. The overall goal of project MICROPATH was to pioneer the development and field validation of a microplastic fate and transport model for predicting the persistence of microplastics and pathogens in streams worldwide. The overarching research objective was to quantify the persistence and fate of microplastics in rivers, and their potential role in disease transmission as a vector of pathogenic bacteria.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The project applied novel hydrologic methods to predict microplastic and pathogen persistence and fate in streams. We improved estimates on the fate and persistence of microplastics in streams by applying a mobile-immobile model that can appropriately characterize their transport and residence time during a wide range in flow conditions (i.e. baseflow and storm flow).

During the project we conducted multiple field studies in Spain and the UK to measure microplastic (and other fine particle) accumulation in streambed sediments. These studies resulted in 3 publications with the datasets publicly available. Model development and application to a global stream dataset was published for steady-state baseflow conditions in 1publication. Furthermore, a model was developed that captures both steady-state baseflow and variable storm flow conditions, encompassing both the deposition and resuspension of microplastics in streams. The model is published in 1 publication, with 3 more forthcoming publications. The results from MICROPATH were presented at 7 scientific conferences.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The project addressed a worldwide issue of concern– how urban activity impacts stream ecosystems and alters the quality of freshwater resources. This topic is easily identifiable with local communities since plastic use is global and WWTPs are widely used and necessary, especially in urban areas to reduce freshwater impacts from urban activity. There were many opportunities to share these learnings through a range of broader public engagement (PE) activities at the University of Birmingham. UoB’s press office and Public Engagement Working Group (PEWG) helped support these activities within MICROPATH that resulted in 3 interviews and publications in Popular Mechanics, Mongabay, and the Institute for Sustainability and Energy at Northwestern. Research was disseminated to the public via updates to Twitter and links to LinkedIn and ResearchGate. The project provided a publicly available model framework to predict microplastic and pathogen transport, which was previously unavailable, that helps mitigate environmental risks and identify high-risk areas within the EU and worldwide. No website was developed for the project. This research combined innovative modeling and sampling techniques to improve the predictions of microplastics and pathogen fate in urban streams, a critical and significant environmental issue that is often highlighted in media outlets in Europe and worldwide.

Microplastics model