Microplastics have been found in the guts of every marine mammal washed up on Britain’s shores.
Researchers from the University of Exeter and Plymouth Marine Laboratory (PML) examined 50 animals from 10 species of dolphins, seals and whales, and found microplastics (less than 5mm) in them all.
Most of the particles (84%) were synthetic, with a report by the Instutition of Mechanical Engineers published last year revealing that 35% of microplastics released into the world’s oceans come from synthetic textiles.
They can also come from sources including fishing nets and toothbrushes, while the rest were fragments, whose possible sources include food packaging and plastic bottles.
‘It’s shocking – but not surprising – that every animal had ingested microplastics,’ said lead author Sarah Nelms, of the University of Exeter and PML.
‘The number of particles in each animal was relatively low (average of 5.5 particles per animal), suggesting they eventually pass through the digestive system, or are regurgitated.
‘We don’t yet know what effects the microplastics, or the chemicals on and in them, might have on marine mammals.
‘More research is needed to better understand the potential impacts on animal health.’
Though the animals in the study died of a variety of causes, those that died due to infectious diseases had a slightly higher number of particles than those that died of injuries or other causes.
Dr Penelope Lindeque, head of the marine plastics research group at Plymouth Marine Laboratory, called the revelations ‘disconcerting’.
‘From our work over the years we have found microplastic in nearly all the species of marine animals we have looked at; from tiny zooplankton at the base of the marine food web to fish larvae, turtles and now dolphins, seals and whales,’ she said.
Earlier this week, a study found that microplastics are affecting the ability of mussels to attach themselves to their surroundings which is having a devastating impact on ocean ecosystems.
Researchers at Anglia Ruskin University found that blue mussels exposed to doses of non-biodegradable microplastics over a period of 52 days produced significantly fewer byssal threads, which are thin fibres that help mussels attach themselves to rocks and ropes.
As well as enabling mussels to survive waves and strong tides, and stay attached to their surroundings, these byssal threads also enable them to form extensive reefs that provide important habitats for other marine animals and plants.