Plastic plays a crucial role in our daily lives; however, it also poses significant global environmental and economic concerns. As plastics enter the ocean, they break down into smaller particles—microplastics and nanoplastics—due to factors such as UV rays, wind, and other environmental influences. These particles are ubiquitous, threatening marine ecosystems and human health. In response to this growing issue, JPI Oceans launched a transnational joint call in 2014 titled "Ecological Aspects of Microplastics in the Marine Environment", which resulted in the funding of four projects running from 2016 to 2019. The findings generated on ecotoxicological effects of microplastics, the weathering of plastics, and baselines for microplastics analyses in European basins are summarised in a short brochure.
Building on the results from the first call, a second call was launched in 2018 by thirteen JPI Oceans member countries, along with Latvia and Brazil. Six new projects were selected for funding to research microplastic sources, identification methods, and effects on marine systems: ANDROMEDA, HOTMIC, FACTS, microplastiX, i-plastic, and RESPONSE. To showcase their outcomes, JPI Oceans just published the summary brochure “Key Insights Microplastics Projects 2020 - 2023”.
Already announced at the 2024 Summit of Plastic Pirates Go Europe, the second brochure on microplastics research covers the latest scientific findings from the six projects of the second joint call, presented in four categories:
1. Microplastics interactions with biota
The brochure emphasises the growing issue of plastic pollution in marine environments and its detrimental effects on ocean ecosystems. Microplastics interact with marine organisms, fostering harmful communities, including bacteria (Vibrio spp.) and invasive worms. The report indicates that many marine species ingest microplastics, affecting their health, while deep-sea creatures may act as a “plastic pump”, transporting particles through ocean layers. Additionally, microplastics present risks to species consumed by humans, such as mussels, affecting their metabolism and immunity. The projects emphasise the urgent need for continued monitoring and management of microplastic pollution to protect marine and human life, and ecosystems too.
2. Microplastics distribution: from rivers and estuaries to the open ocean
The projects investigated the movement and distribution of microplastics across diverse ecosystems, including fjords, beaches, estuaries, and oceans. They highlighted the influence of environmental factors such as rainfall, tides, and human activity on microplastic concentrations. For instance, heavy rainfall in estuaries can spike microplastic levels tenfold, while winds and waves affect their distribution in lakes. The document also identifies wastewater as a critical source of microplastic pollution, noting that urban wastewater treatment plants often fail to eliminate microplastics, particularly microfibers from textiles, which re-enter the environment through treated sludge used as fertiliser. These findings stress the necessity for improved waste management and updated regulations to mitigate the environmental impact of microplastics.
3. Microplastics vertical dispersion: from sea surface to seafloor
In addition to surface distribution, the document explores the vertical movement of microplastics through ocean layers, revealing their complex behaviour. These particles can be found from the ocean's surface to its depths, ultimately accumulating in seafloor sediments. Factors like biofouling and temperature fluctuations influence their sinking rates, especially for high-density polymers. At the sea surface, sea spray can release microplastics into the atmosphere allowing them to travel inland or return to ocean waters. In seafloor sediments, their accumulation poses a threat to benthic organisms. These results highlight the intricate dynamics of microplastic pollution and underscore the urgent need for enhanced management strategies to reduce their environmental impact.
4. Innovations in microplastic analysis methods
The document also showcases groundbreaking research conducted by the projects, including advancements in analytical technologies. For example, the TUM-ParticleTyper 2 software enables the quantification of microplastics down to 1 μm. Furthermore, new protocols for analysing textile microfibers and standardised methods for detecting microplastics in drinking water have been introduced. Enhanced sampling and analysis techniques for both water and air have also been developed, improving cost-effectiveness and accuracy. By providing essential insights and methodologies, this document aims to deepen understanding and drive action against the pervasive threat of microplastics in our ecosystems.
The six projects from the second JPI Oceans’ transnational joint call have advanced microplastic science and public awareness, resulting in approximately 160 publications and presentations at conferences. Collaborations with organisations and policymakers have emphasised the importance of a holistic legislative approach. Outreach activities have included developing a smartphone app for citizen monitoring of beach microplastics, university summer schools, PhD exchange programs, and community engagement initiatives, all underscoring the critical need for effective communication in marine science.
With this new publication, all final reports, scientific papers and presentations of the projects are now summarised, providing their key results in an accessible format.