Currently, plastic pollution in the oceans of the world is broadly accepted as a main global issue; however, only little is known about how these plastics are actually ending up in the sea.
A new global program, headed by the University of Birmingham, demonstrates how focusing on rivers and river mouths can offer important clues about how this plastic crisis might be tackled.
The 100 Plastic Rivers Project is associating with researchers in over 60 locations across the world to sample water and sediment in rivers. The objective is to gain better insights into how plastics are carried and converted in rivers and how they get deposited in river sediments, where they establish a long-lasting pollution legacy.
Initial outcomes of the project will be exhibited at the General Assembly of the European Geosciences Union (EGU), conducted at Vienna, Austria, from April 7th to 12th, 2019. They represent an intricate picture, with vast diversity in sources and kinds of plastic in chosen river estuaries in France and the United Kingdom.
Even if we all stopped using plastic right now, there would still be decades, if not centuries-worth of plastics being washed down rivers and into our seas. We’re getting more and more aware of the problems this is causing in our oceans, but we are now only starting to look at where these plastics are coming from, and how they’re accumulating in our river systems. We need to understand this before we can really begin to understand the scale of the risk that we’re facing.
Professor Stefan Krause, School of Geography, Earth and Environmental Sciences, University of Birmingham
The 100 Plastic Rivers programme investigates primary microplastics, for example, micro-beads used in cosmetics, as well as secondary microplastics, for instance, from larger plastic items that have disintegrated in the environment or fibers from clothing.
An important part of the project is to develop a standard approach for the sampling and analysis of microplastics, which can be used to give an evaluation of the plastic pollution of the river networks. The Birmingham team has created a toolkit, with complete instructions for sampling water and river sediments at regions where stream flow is known or determined, and developed techniques for automating, thereby, objectifying the identification and analysis of microplastics.
In a pilot work concluded recently, the University of Birmingham group partnered with the Clean Seas Odyssey citizen science project to investigate parts of the devised methodology based on sampling water and sediments from river estuaries across the United Kingdom and France Channel coast. The analysis of the samples obtained by interested members of the public enabled them to test the sampling protocol and create a picture of the various types of polymers accumulated in river sediments at the place where they join the sea.
The outcomes of this initial survey revealed a much broader range of plastic types in the samples than had been expected. This indicates that even in moderately well-regulated countries such as France and the United Kingdom, there is a range of different sources contributing to a high concentration of microplastics in river systems.
The work is funded by the Leverhulme Trust, the EU Horizon 2020 Framework, the Royal Society, and the Clean Seas Odyssey.