The AWI’s citizen science initiative, ‘Microplastic Detectives’, has examined 2.2 tons of sand gathered from Germany’s coastlines for microplastics.
The global production of plastics, along with the subsequent waste generated, has surged to the point where plastics are now found everywhere in our environment. Various sizes of plastics are evident along the North Sea and Baltic coasts of Germany. Past research on microplastic contamination at German beaches was often confined to specific sites. In the “Microplastic Detectives” citizen science project, researchers from the Alfred Wegener Institute teamed up with local volunteers to gather samples from beaches all along the German coastline for microplastic analysis. This dataset is the first to provide a sufficiently comprehensive view of pollution levels across the entire German coast. The team’s findings are published in the journal Frontiers in Environmental Science.
Estimates from the Organisation for Economic Co-operation and Development (OECD) suggest that global plastic production could nearly triple by the year 2060. This rise would contribute to increased plastic waste and accumulation in water bodies, where plastics disintegrate into microplastics — tiny particles measuring five millimeters or smaller. Dr. Bruno Walther, previously of the Alfred Wegener Institute and now at Heinrich Heine University Düsseldorf, highlights that “this irreversible plastic pollution impacts species, populations, and ecosystems, including those along the German coast.” Up until now, evaluations of pollution on North Sea and Baltic Sea beaches only covered specific locations, not the entire German coastline. “This motivated us to initiate the citizen research project ‘Microplastic Detectives’ to gather comparable information on the widespread distribution of microplastic pollution throughout the German coastline.”
With the aid of citizen scientists, the research team collected a total of 2.2 tons of sand from 71 locations across the German coast, covering an area of 68.36 square meters. “We assembled 1139 comparable samples into a unified dataset, providing more geographic coverage than we’ve had before,” shares Dr. Melanie Bergmann, a co-author and biologist at AWI. The gathered samples were dried, sifted, and examined under a microscope for plastic particles as small as one millimeter. “In this study, we specifically concentrated on larger microplastics to eliminate contaminations from airborne small microplastics and to simplify the collection process for citizen scientists.”
The results were unexpected: “We detected plastic on 52 of the 71 beaches; however, the levels of large microplastics in the North Sea and Baltic Seas were lower than those reported in other studies,” explains Bruno Walther. “Had we examined smaller microplastics as well, we likely would have found much higher concentrations,” adds Melanie Bergmann. Previous studies conducted by AWI in the North Sea and Arctic regions found that microplastics smaller than one millimeter made up over 90% of those found in sediments. “We also randomly selected sampling locations on the beach instead of targeting accumulation zones like drift lines. This might also account for the observed differences.”
Out of the 1139 samples analyzed, 177 revealed a total of 260 plastic particles, averaging about four plastic particles per square meter. In a ten-hectare beach area, this translates to approximately 400,000 plastic particles. Nonetheless, the analysis indicates that microplastic pollution can differ significantly by location.
Assessing policy effectiveness and areas for improvement
As Melanie Bergmann emphasizes, “Our study is the first to deliver comparable data on the large-scale distribution of plastic pollution along the entire German coastline using standardized methods.” This information is crucial for mapping current pollution levels and gauging the success of future policies aimed at reducing plastic waste. For instance, monitoring suggests that legislative adjustments over the past quarter-century may have resulted in fewer plastic bags being discovered on the seafloor in north-west Europe. “However, we need stronger, science-driven policies that establish definitive regulations on minimizing, reducing, and recycling plastics.” Such measures should focus on limiting plastic production and use to essential applications, banning harmful ingredients, increasing natural degradability, and allowing for circular resource usage.
The “Microplastic Detectives” project also demonstrates that citizen-inclusive monitoring initiatives for thorough and timely data collection can be effective. There is a significant interest in assisting scientific efforts to combat plastic pollution: “We were amazed by the number of citizen scientists who dedicated countless hours on the beach to carefully collect, package, and send samples. We are sincerely grateful for their commitment,” remarks Bruno Walther. “Ideally, our project’s outcome would serve as a model for sustained and more rigorous monitoring of microplastic pollution on German beaches,” adds Melanie Bergmann. “This is essential if we want to evaluate and adjust critical measures necessary for addressing the challenges posed by plastics and their detrimental effects on our coastal ecosystems, tourism, and human health.” Although the “Microplastic Detectives” project has concluded, there are still opportunities for citizens to engage in initiatives like the Plastic Pirates citizen science project, which allows schoolchildren to gather data on plastic pollution along coasts and rivers.
