Scientists Use Mussels to Track Rising Microplastic Pollution in the Mediterranean

Overtourism and heavy maritime traffic in the Mediterranean Sea are leading to increased pollution in Greece’s coastal waters, according to Greek scientists.

• Researchers warn that the Mediterranean, a semi-enclosed basin, has become a hotspot for microplastic contamination.

Use of Mussels

• Scientists from the Hellenic Centre for Marine Research (HCMR) have deployed thousands of mussels on the seafloor to monitor microplastic levels.
• Mussels, being filter-feeding organisms, absorb various contaminants — including invisible microplastics — making them effective bioindicators of marine pollution.

Methodology

• In May 2025, researchers submerged cages containing mussels at different depths and locations across Greece — from busy ports to remote islands.
• The mussels were retrieved in September 2025 for laboratory analysis to determine the type and quantity of microplastics absorbed.
• For surface water testing, scientists used a floating net device to collect samples.

Findings

• The microplastic particles found in mussels and water samples varied in form — including fragments, films, microfibres, and pellets.
• Most particles were blue or transparent, suggesting they originated from single-use plastics such as rubbish bags and water bottles.
• Over time, sunlight, waves, and ocean currents break down these plastics into microscopic particles, making detection increasingly difficult.

Source: DD