A unique citizen science project, led by researchers from the Alfred Wegener Institute (AWI), involved collecting sand samples from 71 beaches along the German North and Baltic Sea coasts to study microplastic contamination.

Over the course of a year, participants gathered more than 1,100 samples, totaling 2.2 metric tons of sand, which were analyzed for microplastics measuring between one and five millimeters.

The findings, published in 'Frontiers in Environmental Science', revealed significant levels of microplastics on Germany's coastal beaches, with some locations showing up to 400,000 plastic particles.

Out of the 1,139 samples analyzed, 177 contained a total of 260 plastic particles, averaging about four particles per square meter, although the levels varied significantly by location.

Plastic was found at 52 out of the 71 beaches surveyed, but the concentration of larger microplastics was lower than in previous studies, indicating a need for ongoing monitoring.

AWI biologist Melanie Bergmann noted that including smaller microplastics would likely have resulted in much higher concentration levels, as smaller particles comprise over 90% of microplastics in earlier research.

Lead author Bruno Walther emphasized that their random sampling method differed from other research that typically focused on pollution hotspots, providing a broader understanding of microplastic distribution.

The study underscores the need for stronger, science-based policies to manage plastic pollution effectively, including stricter regulations on production and recycling.

Monitoring results suggest that legislative changes may have contributed to a decrease in plastic bags found on the seabed in Northwest Europe over the past 25 years, highlighting the importance of effective policies.

Despite these findings, the OECD projects that global plastic production could nearly triple by 2060, exacerbating microplastic pollution and threatening marine ecosystems.

Although the 'Microplastic Detectives' project has concluded, citizens are encouraged to participate in related initiatives like the Plastic Pirates project to continue monitoring plastic pollution.

Standardized methods were crucial for assessing the current state of pollution and evaluating the effectiveness of political measures aimed at reducing plastic waste.