The research, carried out by the University of Aveiro's Centre for Environmental and Marine Studies (CESSAM), reveals plastic pollution in species such as the zyphus, the pygmy sperm whale and the sperm whale, based on autopsies carried out on cetaceans found off the Portuguese and Spanish coasts.

‘Half of the cetaceans stranded between 1990 and 2019 had rubbish in their digestive system,’ says the study, referring to various ingested materials, “being the cause of death in many cases”.

Biologist Sara Sá, from CESSAM, explains that ‘analysing the digestive systems of these animals revealed the presence of plastic bags and packaging, plastic and metal fishing materials, other metal objects and even leather gloves’.

‘We're talking about a universe of 107 stranded individuals, with samples collected since 2000 in Portugal and 1990 in Spain,’ Sara Sá told Lusa.

The researcher emphasises that the materials found are related to fishing and domestic use.

The study explains that ‘the ingestion of marine macro-litter (rubbish larger than 2.5 centimetres) is frequent among deep-sea diving cetaceans off the Ibero-Atlantic coast’.

The study was carried out in collaboration with the Spanish research networks Coordinadora para el Estudio de los Mamíferos Mariños (CEMMA) and Coordinadora para el Est (CEPESMA).