Friday, 01 February 2019 17:00

Dying in a sea of litter: Shocking study reveals every one of 50 dead dolphins, seals and whales found washed up on UK coastline were poisoned by plastic

Scientists conducted a study of marine animals that washed up on British shores

They discovered that all of them had microplastic particles in their stomachs  

But the majority were synthetic fibres shed from fishing nets and clothes 

Visit to sign up to the Daily Mail's Great British Spring Clean campaign today





Britain's seas are now so polluted with plastic that particles were found in the guts of all 50 dead mammals examined in a study.

Scientists analysed the bodies of dolphins, porpoises, seals and whales found washed up on our shores.

Microplastics less than 5mm in diameter were present in the digestive tracts of every single one. 

Most of the particles – 84 per cent – were synthetic fibres which can come from clothes, toothbrushes and fishing nets, with 60 per cent nylon and 10 per cent polyester. 


The remainder had broken down from larger objects such as plastic bottles and food packaging.

The lead author of the study called the findings ‘shocking, but not surprising’.

Sarah Nelms, of the University of Exeter, said the number of particles in each animal ‘was relatively low – an average of 5.5 particles per animal’ suggesting they ‘eventually pass through the digestive system or are regurgitated’. 

However, she warned: ‘We don’t yet know what effects the microplastics, or the chemicals on and in them, might have on marine mammals. 

'The low number of microplastics in their gut at any one time doesn’t necessarily correlate to the chemical burden within their body because the exposure is chronic and cumulative.

‘It’s also not yet understood how synthetic particles physically interact with the gut wall as they pass through.’



Scientists fear bacteria, viruses and contaminants are carried on plastics into an animal’s guts, spreading disease.

In the study, on animals found from Cornwall to Scotland, the mammals had died from a variety of causes – but those that died due to infectious diseases had a slightly higher number of particles than those that died from accidents or natural causes.

Dr Penelope Lindeque, head of the marine plastics research group at Plymouth Marine Laboratory, said microplastics had been found in animals at every level of the food chain, from tiny zoo plankton to fish larvae, turtles, and now marine mammals. 

She added: ‘It’s disconcerting ... this study provides more evidence that we all need to help reduce the amount of plastic waste released to our seas and maintain clean, healthy and productive oceans for future generations.’

In total, 26 species of marine mammal are known to inhabit or pass through British waters. 

The ten species examined in the study included five types of dolphin, grey seals and harbour seals, harbour porpoises and a pygmy sperm whale.


Species with a long life span such as dolphins and seals are good indicators of pollution levels in the sea, and as top predators they are susceptible to a build-up of plastics from the smaller creatures in their diet. 

Professor Brendan Godley, of the Centre for Ecology and Conservation at the University of Exeter, said: ‘Marine mammals are ideal sentinels of our impacts on the marine environment. Our findings are not good news.’


While numerous studies have shown the growing extent of larger plastic litter eaten by sea mammals, the latest study is the most comprehensive analysis of microplastics in their digestive tracts.

Worldwide around eight million tons of plastic rubbish is washed into the oceans every year. 

Microplastics come from a variety of sources, including the breakdown of larger debris, waste water containing fibres from synthetic clothes and textiles and road run-off containing fragments of tyres and paint. 

Their ingestion by sea creatures has been shown to cause a reduction in feeding and energy reserves, as well as damage to the brain and other organs.

The study, published in Scientific Reports, was supported by Greenpeace Research Laboratories.


Louise Edge, head of Greenpeace UK’s ocean plastics campaign, said: ‘It is ominous that every single marine mammal tested was found to have microplastics in their digestive system, and it shows the scale of plastic pollution in our seas. 

'This is yet more evidence that the Government and big businesses need to focus their efforts on drastically reducing the use and waste of plastics, to stem the flow of plastic pollution into our rivers and oceans and into the mouths of marine wildlife.’

A Sustainable Seas Report published by the Environment Audit Committee last month called on the Government to set stricter targets for reducing single-use plastic in the UK to help stop our oceans being used as a sewer.

A separate study last year by the University of Manchester found high levels of microplastics in Britain’s rivers and evidence that much of it is washed towards the sea during flooding.

The researchers tested river sediment at 40 sites across the city and surrounding areas and found microplastics in all of them. 

  • Michael Gove last night launched the Year of Green Action, a drive to get more people involved in projects to improve the natural world.

Speaking at London Zoo, the Environment Secretary said £10million will be set aside to help design more outdoor activities for schools with children from disadvantaged backgrounds.