Microplastic Deposits Found Deep in World`s Oceans and

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Microplastic Deposits Found Deep in World`s Oceans and
Full Scale of Plastic in the World's Oceans Revealed for First Time
Source: http://www.theguardian.com/environment/2014/dec/10/full-scale-plastic-worlds-oceans-revealed-firsttime-pollution
By: Oliver Milman Wednesday 10 December 2014
Over five trillion pieces of plastic are floating in our oceans says most comprehensive study to date on plastic
pollution around the world
Plastic pieces in the ocean damage wildlife and enter the food
chain when ingested by fish. Photograph: Bryce
Groark/Alamy
More than five trillion pieces of plastic, collectively weighing nearly 269,000 tonnes, are floating in the world’s
oceans, causing damage throughout the food chain, new research has found.
Data collected by scientists from the US, France, Chile, Australia and New Zealand suggests a minimum of 5.25tn
plastic particles in the oceans, most of them “micro plastics” measuring less than 5mm.
The volume of plastic pieces, largely deriving from products such as food and drink packaging and clothing, was
calculated from data taken from 24 expeditions over a six-year period to 2013. The research, published in the
journal PLOS One, is the first study to look at plastics of all sizes in the world’s oceans.
Large pieces of plastic can strangle animals such as seals, while smaller pieces are ingested by fish and then fed up
the food chain, all the way to humans.
This is problematic due to the chemicals contained within plastics, as well as the pollutants that plastic attract once
they are in the marine environment.
“We saw turtles that ate plastic bags and fish that ingested fishing lines,” said Julia Reisser, a researcher based at the
University of Western Australia. “But there are also chemical impacts. When plastic gets into the water it acts like a
magnet for oily pollutants.
“Bigger fish eat the little fish and then they end up on our plates. It’s hard to tell how much pollution is being
ingested but certainly plastics are providing some of it.”
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The researchers collected small plastic fragments in nets, while larger pieces were observed from boats. The
northern and southern sections of the Pacific and Atlantic oceans were surveyed, as well as the Indian ocean, the
coast of Australia and the Bay of Bengal.
The vast amount of plastic, weighing 268,940 tonnes, includes everything from plastic bags to fishing gear debris.
While spread out around the globe, much of this rubbish accumulates in five large ocean gyres, which are circular
currents that churn up plastics in a set area. Each of the major oceans have plastic-filled gyres, including the wellknown ‘great Pacific garbage patch’ that covers an area roughly equivalent to Texas.
Reisser said traversing the large rubbish-strewn gyres in a boat was like sailing through “plastic soup.”
“You put a net through it for half an hour and there’s more plastic than marine life there,” she said. “It’s hard to
visualise the sheer amount, but the weight of it is more than the entire biomass of humans. It’s quite an alarming
problem that’s likely to get worse.”
The research found that the gyres themselves are likely to contribute to the problem, acting as “shredders” to the
plastic before dispersing it.
“Our findings show that the garbage patches in the middle of the five subtropical gyres are not the final resting
places for the world’s floating plastic trash,” said Marcus Eriksen, another of the report’s co-authors. “The endgame
for micro-plastic is interactions with entire ocean ecosystems.”
The research, the first of its kind to pull together data on floating plastic from around the world, will be used to
chart future trends in the amount of debris in the oceans.
But researchers predict the volume will increase due to rising production of throwaway plastic, with only 5% of the
world’s plastic currently recycled.
“Lots of things are used once and then not recycled,” Reisser said. “We need to improve our use of plastic and also
monitor plastics in the oceans so we get a better understanding of the issue.
“I’m optimistic but we need to get policy makers to understand the problem. Some are doing that – Germany has
changed the policy so that manufacturers are responsible for the waste they produce. If we put more responsibility
on to the producer then that would be part of the solution.”
Microplastic Deposits Found Deep in World's Oceans and Seas
Source: http://www.theguardian.com/environment/2014/dec/17/microplastic-deposits-found-deep-in-worldsoceans-and-seas
By: Adam Vaughan Wednesday 17 December 2014
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Study of 12 sites concludes that deep sea sediments are acting as a sink for substantial quantities tiny pieces of
plastic
Samples of plastic waste level in ocean water taken in the North
Pacific. Photograph: Getty Images
Scientists believe they have solved the mystery of where tens of thousands of tonnes of missing tiny pieces of plastic
are ending up – and the answer lies in the mud and sand on the ocean floor.
Researchers have previously been puzzled by why they found much less plastic on the ocean surface than they
expected, but a study by a British and Spanish team concludes that deep sea sediments are acting as a sink for such
“microplastics”.
Analysing samples from 12 sites in the Atlantic Ocean, Mediterranean Sea and Indian Ocean taken between 2001
and 2012, they found for the first time that substantial quantities of microplastics – which measure less than 1mm in
length – had accumulated in deep sea sediment.
The tiny fibres were found at depths from 300m down at the shallowest in the Mediterranean to over 3,000m deep,
at volumes 1,000 times higher than those at the surface of the sea.
Prof Lucy Woodall, of the Natural History Museum in London and the paper’s lead author, said: “This is the tip of
the iceberg. Fibres are ubiquitous in our oceans and they do appear to be quite abundant in comparison with similar
studies that have looked at similar things. The fundamental message of the paper is really quite simple: they’re there.
Now we need to find out what the impacts are on our environment.”
A study earlier this month, the most comprehensive of its kind so far, estimated there are more than 5tn pieces of
plastic in the world’s oceans, weighing nearly 269,000 tonnes. But the authors, who collected tens of thousands of
pieces of plastic and then extrapolated that to model how many would be found worldwide, cautioned that the
amount was just 0.1% of annual global plastic production.
The new work sampling deep sea sediments, published in the Royal Society Open Science journal on Wednesday,
found pieces of plastic that were commonly 2–3 mm in length and less than 0.1 mm in diameter.
“The prevalence of plastic microfibres in all sediment cores and on all coral colonies examined suggests this
contaminant is ubiquitous in the deep sea. Furthermore, the wide variety of polymer types detected reveals that the
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accumulation and deposition of microfibres in the deep sea is complex and that they arise from a variety of
domestic and industrial sources,” the study said.
Woodall added: “Pretty much everything [is a potential source for what we found]. Just look around in our
environment, our computers have plastic, our bags have, our cups have. All those things can potentially end up in
the ocean, so to pinpoint any particular source is just not possible.”
The abundance of plastic at such depths has potentially negative ramifications for marine life, though the study says
more research is needed. “A range of organisms are known to ingest microplastics, and there is concern this could
result in physical and/or toxicological harm,” the authors warn.
Study Gauges Plastic Levels in Oceans
Source: http://www.nytimes.com/2014/12/11/science/new-research-quantifies-the-oceans-plastic-problem.html
By JOHN SCHWARTZ DEC. 10, 2014
Plastic debris washed up on a beach in Azores,
Portugal. CreditMarcus Eriksen
It is no secret that the world’s oceans are swimming with
plastic debris — the first floating masses of trash were
discovered in the 1990s. But researchers are starting to get a
better sense of the size and scope of the problem.
A study published Wednesday in the journal PLOS One
estimated that 5.25 trillion pieces of plastic, large and small,
weighing 269,000 tons, could be found throughout the
world’s oceans, even in the most remote reaches.
The ships conducting the research traveled the seas collecting small bits of plastic with nets and estimated
worldwide figures from their samples using computer models. The largest source of plastic by weight comes from
discarded fishing nets and buoys, said Marcus Eriksen, the leader of the effort and co-founder of the 5 Gyres
Institute, a nonprofit group that combines scientific research with antipollution activism.
Dr. Eriksen suggested that an international program that paid fishing vessels for reclaimed nets could help address
that issue. But that would do nothing to solve the problem of bottles, toothbrushes, bags, toys and other debris that
float across the seas and gather at “gyres” where currents converge. The pieces of garbage collide against one
another because of the currents and wave action, and sunlight makes them brittle, turning these floating junkyards
into “shredders,” he said, producing smaller and smaller bits of plastic that spread far and wide.
When the survey teams looked for plastics floating in the water that were the size of grains of sand, however, they
were surprised to find far fewer samples than expected — one-hundredth as many particles as their models
predicted. That, Dr. Eriksen said, suggests that the smaller bits may be swept deeper into the sea or consumed by
marine organisms.
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The result echoed that of a paper published this year in Proceedings of the National Academy of Sciences that
found a surprisingly low amount of small plastic debris. Those researchers estimated as much as 35,000 tons of the
smaller debris were spread across the world’s oceans, but they had expected to find millions of tons.
Andrés Cózar, a researcher from the University of Cadiz who headed that study, said in an email that he and Dr.
Eriksen came to different conclusions about the amount of plastic afloat, but that “it is evident that there is too
much plastic in the ocean,” adding, “The current model of management of plastic materials is (economically and
ecologically) unsustainable.”
The fact that the small plastics are disappearing is hardly good news. In fact, it could be far more troubling than the
unsightly mess the plastics cause. Plastics attract and become coated with toxic substances like PCBs and other
pollutants. Researchers are concerned that fish and other organisms that consume the plastics could reabsorb the
toxic substances and pass them along to other predators when they are eaten.
“Plastics are like a cocktail of contaminants floating around in the aquatic habitat,” said Chelsea M. Rochman, a
marine ecologist at the University of California, Davis. “These contaminants may be magnifying up the food chain.”
The ocean studies make an important contribution to the understanding of the floating waste problem, said Nancy
Wallace, director of the marine debris program for the National Oceanic and Atmospheric Administration.
Further research should look beyond the surface to test where the smaller plastic bits might have gone: into the
deeper ocean depths, along the shoreline or settled on the seafloor. “It’s premature to say there is less plastic in the
ocean than we thought,” she said. “There may just be less where we’re looking.”
Dr. Eriksen said the scope of the problem makes floating garbage collection impractical. His group has had some
success with campaigns to get manufacturers of health and beauty aids to stop using small scrubbing beads of
plastic in their products.
Manufacturers of other products, he said, must be urged to change their practices as well. “We’ve got to put some
onus on producers,” he said. “If you make it, take it back, or make sure the ocean can deal with it in an
environmentally harmless way.”
Dr. Wallace agreed. “Unless we can stop the flow — turn off the tap of these pieces of debris going into the ocean
all the time — we’re not going to be able to stop the problem.”
The American Chemistry Council, which speaks for the plastics industries, issued a statement saying that its
members “wholeheartedly agree that littered plastics of any kind do not belong in the marine environment,” and it
cited industry efforts to combat the problem, including the 2011 Declaration of the Global Plastics Associations for
Solutions on Marine Litter, which has led to 185 projects around the world.
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