Investigators at the Science Centre for the Sea and Environment (MARE) have found rocks with plastic crusts on Madeira Island. The phenomenon has been dubbed as ‘plasticrust’, and its origins are still to be determined.


As far as explanations go, Scientist Ignacio Gestoso said that ‘probably, the crusts were formed by the collision of larger pieces of plastic against the shore, which caused the plastic to form a crust, in the same way as algae and lichens’.


One of the possible side-effects of this new phenomenon is that plastic replaces other natural crusts, which have been serving as a food source for other species. This leads to concerns that those same species might be feeding on plastic now, further spreading the material into nature.


The team of Gestoso found that there were periwinkles feeding on algae that covered the plastic crust, which raises the hypothesis that the animals are also eating plastic, which may lead to particles of the material blocking the digestive tract or lead to pollutants in their system.


The first time the plastic crusts were detected was in 2016, but earlier this year, the team from the centre of NOVA School of Science and Technology in Lisbon returned to the site and saw that the plastic was still embedded in the rocks, in what may be considered “a new category of marine waste,” MARE said in a statement.