Scientists have found an unprecedented number of microplastics frozen in Arctic sea ice, demonstrating the alarming extent to which they are pervading marine environments.

Analysis of ice cores from across the region found levels of the pollution were up to three times higher than previously thought.

Each litre of sea ice contained around 12,000 particles of plastic, which scientists are now concerned are being ingested by native animals.

Based on their analysis, the researchers were even able to trace the tiny fragments’ paths from their places of origin, from fishing vessels in Siberia to everyday detritus that had accumulated in the infamous Great Pacific Garbage Patch.

“We are seeing a clear human imprint in the Arctic,” the study’s first author, Dr Ilka Peeken, told The Independent.

“It suggests that microplastics are now ubiquitous within the surface waters of the world’s ocean,” said Dr Jeremy Wilkinson, a sea ice physicist at the British Antarctic Survey who was not involved with the study.

“Nowhere is immune.”

AWI scientist Julia Gutermann analysing an Arctic sea ice core for microplastic particles in a lab at the AWI Helgoland (Tristan Vankann)

Dr Peeken and her team at the Alfred Wegener Institute for Polar and Marine Research collected ice core samples over the course of three expeditions on the research icebreaker Polarstern.

Their voyages covered five regions along the Transpolar Drift and Fram Strait, which channel sea ice from the Central Arctic to the North Atlantic.

Not only is polar sea ice acting as a store for ocean plastic that could potentially be released as global temperatures get warmer due to climate change, the movement of sea ice could be depositing microplastics in areas that were previously plastic-free.

The researchers analysed their samples using a device known as a Fourier-transform infrared spectrometer.

This enabled them to examine the ice cores layer by layer and in great detail, working out the origins of even the tiniest shards of plastic.

“What is interesting also is you have very localised sources – ship paint particles and cigarette butts and stuff like that,” said Dr Peeken.

“We also see polyethylene, a very light polymer which is found in really high numbers particularly in the Central Arctic. We think that there is an incoming flow from the Pacific so that could show that is coming from that region.

“We see a large impact of plastic pollution coming from the urban areas – a lot is coming from the Atlantic and from the Pacific.”

A study released earlier this year revealed 80,000 tonnes of plastic are floating in this area of the Pacific Ocean, and nonprofit technology firm The Ocean Cleanup recently revealed its first attempt to remove some of it.

Plastic waste across the world: in pictures Show all 15 1 /15 Plastic waste across the world: in pictures Plastic waste across the world: in pictures A father and son on a makeshift boat made from styrofoam paddle through a garbage filled river as they collect plastic bottles that they can sell in junkshops in Manila. The father and son team earn some three US dollars a day retrieving recyclables from the river. AFP/Getty Plastic waste across the world: in pictures A composite image of items found on the shore of the Thames Estuary in Rainham, Kent. Tons of plastic and other waste lines areas along the Thames Estuary shoreline, an important feeding ground for wading birds and other marine wildlife. Getty Images Plastic waste across the world: in pictures Children collect plastic water bottles among the garbage washed ashore at the Manila Bay. According to the United Nations Environment Programme, at current rates of pollution, there will likely be more plastic in the sea than fish by 2050. AFP/Getty Plastic waste across the world: in pictures Plastics and other detritus line the shore of the Thames Estuary. In December 2017 Britain joined the other 193 UN countries and signed up to a resolution to help eliminate marine litter and microplastics in the sea. It is estimated that about eight million metric tons of plastic find their way into the world's oceans every year. Once in the Ocean plastic can take hundreds of years to degrade, all the while breaking down into smaller and smaller 'microplastics,' which can be consumed by marine animals, and find their way into the human food chain. Getty Plastic waste across the world: in pictures A dump site in Manila in 2013. The Philippines financial capital banned disposable plastic shopping bags and styrofoam food containers, as part of escalating efforts across the nation's capital to curb rubbish that exacerbates deadly flooding. AFP/Getty Images Plastic waste across the world: in pictures Children swims in the sea full of garbage in North Jakarta, Indonesia. Getty Plastic waste across the world: in pictures An Indian woman holds a jar filled with Yamuna river water polluted with froth and toxic foam to be used for rituals at the river bank in New Delhi, India. The Yamuna River, like all other holy rivers in India, has been massively polluted for decades now. The river that originates in a glacier in the pristine and unpolluted Himalayas, and flows through Haryana, Delhi and Uttar Pradesh before merging with the Ganges River in Allahabad, once used to be the lifeline of the Indian capital. Currently, it is no more than a large, open sewer that is choking with industrial and domestic discharge that includes plastic, flowers and debris and has virtually no aquatic life. EPA Plastic waste across the world: in pictures Plastic waste is washed up on South Troon beach in Scotland. Recent reports by scientists have confirmed, plastics dumped in the world oceans are reaching a dangerous level with micro plastic particles now being found inside filter feeding animals and amongst sand grains on our beaches. Getty Plastic waste across the world: in pictures Children collect plastic to be sold and recycled, in a polluted river in suburban Manila. The city's trash disposal agency traps solid waste floating down waterways that was thrown into the water by residents of slums along riverbanks upstream. AFP/Getty Plastic waste across the world: in pictures View of the Carpayo Beach in La Punta, Callao, some 15 km of Lima. In 2013, the NGO VIDA labeled the Carpayo Beach as the most polluted in the country - 40 tons of trash on each 500m2. AFP/Getty Plastic waste across the world: in pictures Trash from Kamilo Beach in Hawaii. Gabriella Levine/Flickr Plastic waste across the world: in pictures A scavenger collects plastic cups for recycling in a river covered with rubbish near Pluit dam in Jakarta. Reuters Plastic waste across the world: in pictures Rubbish fills Omoa beach in Honduras. Floating masses of garbage offshore from some of the Caribbean's pristine beaches are testimony to a vast and growing problem of plastic pollution heedlessly dumped in our oceans, locals, activists and experts say. AFP/Getty Plastic waste across the world: in pictures A man climbs down to a garbage filled river in Manila. Plastic rubbish will outweigh fish in the oceans by 2050 unless the world takes drastic action to recycle the material, a report warned in 2016. AFP/Getty Plastic waste across the world: in pictures Garbage on East Beach, Henderson Island (Pitcairn Islands), in the south Pacific Ocean. The uninhabited island has been found to have the world's highest density of waste plastic, with more than 3,500 additional pieces of litter washing ashore daily at just one of its beaches. EPA

Besides this plastic being channelled in from outside the polar regions, the researchers were also able to link some of the microplastics they found to local pollution in the Arctic Ocean itself.

In ice cores collected in Siberia, the predominant forms of microplastic included paint particles from ships and nylon waste from fishing nets.

Over half the microplastic particles trapped in the ice were less than a twentieth of a millimetre wide, meaning they could easily be ingested by small Arctic creatures.

“While we don’t yet know the full extent of the impact of microplastics on the health of the marine environment or humans, the growing body of evidence suggests microplastic pollution is a contaminant of environmental and economic concern,” said Dr Pennie Lindeque, lead plastics scientist at Plymouth Marine Laboratory, who was not involved with the study.

“As microplastics can look like prey for marine animals and are small in size they may be eaten by a wide range of species, from zooplankton – small animals at the base of the food web – to seabirds and whales, potentially impacting marine ecosystems and the food chain.”

Music made from sounds of Cornish sea created to raise money to tackle plastic pollution

Other scientists welcomed the research as “a benchmark study” that demonstrated the extent to which plastics both big and small have covered the world.

However, given the scale of the global plastic crisis, they said its conclusions did not come as a surprise.

Professor Richard Thompson, an ocean plastic researcher at the University of Plymouth who first coined the use of the term microplastics, said this study builds on work he conducted to establish their concentration in Arctic ice.

“The study reinforces what is already clear to many marine scientists – that plastic debris is a highly persistent form of contamination that can accumulate in considerable concentrations even in remote locations far from the likely points of entry to the ocean,” he told The Independent.

“What is increasingly clear is the urgency with which we need to take steps to halt the flow of plastic debris to the ocean.