Scientists in Greece say that heavy maritime traffic and overtourism in the Mediterranean region are contributing to the pollution of the azure waters in Greece. They have placed thousands of mussels to detect microplastics on the seabed.

Since decades, mussels, which are filter-feeding organisms and absorb contaminants, including microplastics invisible, into their tissues, have been used as a global barometer for marine pollution.

Researchers at the Hellenic Centre for Marine Research have been using these in Greece. The country's pristine beaches, and its azure waters attract millions of tourists each year.

They submerged mussel cages in May at different depths, and from various locations, including busy ports, to remote islands. In September, they retrieved the mussels to analyze the particles that had accumulated. They use a floating device to test the surface water.

"It's amazing that you can collect these microplastics in only two kilometres," said oceanographer Argyro Adamsopoulou from the HCMR lab, referring samples taken from the net used to filter the water.

Scientists said that the entire Mediterranean Sea basin, which is semi-enclosed, has been a hotspot of microplastics.

Nikoletta Digka, a biologist at HCMR, explained that the particles found in Greece were mainly blue or transparent and varied in size from small fragments to microfibres, pellets or film. They came from plastics used for single-use, like water bottles and rubbish bags.

Over time, they are eroded by sun, waves and currents, making them harder to detect.

Digka said that although the concentrations of microplastics in each species are too low to cause harm to humans, they are present in all species analysed by his team.

Digka stated that "on average, we found one or two microplastics for every population we analysed." Digka warned that if action is not taken, the fragmentation of plastics will continue to increase, increasing the amount of microplastics consumed by marine organisms and raising the risk level for humans. (Reporting and writing by Stelios Mizinas, Renee Maltezou, Editing by Edward McAllister and William Maclean).

(source: Reuters)