Over a quarter of a million tons of plastic waste are bobbing around the world’s oceans, a new study suggests. This challenges previous much lower estimates. To obtain the data, scientists from four continents basically fished for plastic for six years.
“A minimum of 5.25 trillion [plastic] particles weighing 268,940 tons” are currently floating in our oceans, suggests a study by researchers from the US, France, Chile, Australia and New Zealand, which was released on Wednesday.
To arrive at the estimate they carried out 24 expeditions around the globe between 2007 and 2013, when they collected small plastic debris with the help of narrow mesh nets and also visually estimated the volume of large floating waste.
Plastic Pollution in World's Oceans: > 5 Trillion Pieces Weighing > 250,000 Tons Afloat at Sea http://t.co/cOH3sThu0spic.twitter.com/hzxGaqTB4K
— PLOS ONE (@PLOSONE) December 10, 2014
“There's much more plastic pollution out there than recent estimates suggest," Marcus Eriksen, research director for the Los Angeles-based 5 Gyres Institute, who led the study, told Reuters.
“It's everything you can imagine made of plastic. It's like Walmart or Target set afloat.”
A previous study on the issue, published in July, gave far more modest figures, estimating between 7,000 and 35,000 tons of plastic waste.
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Authors of the most recent study think their estimate of plastic waste could be the tip of the iceberg. They cite statistics by Plastics Europe saying 288 million tons of plastic were produced worldwide in 2012.
“Our estimate of the global weight of plastic pollution on
the sea surface, from all size classes combined, is only 0.1% of
the world annual production,” the researchers
say.
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The scientists have stressed their estimates are “highly conservative, and may be considered minimum.” They only took into account the floating plastic garbage, disregarding the waste found on shores and on the seabed.
Another unaccounted for type of plastic is one that can only be found “within organisms.” Researchers believe that large portions of “microplastics,” less than 5mm in size, could disappear in fish bellies, thus entering the human food chain.
“Bigger fish eat the little fish and then they end up on our plates,” Julia Reisser, from the University of Western Australia, who participated in the research, told The Guardian. “It’s hard to tell how much pollution is being ingested but certainly plastics are providing some of it.”
And plastic appears to be spreading faster than previously thought. Although the waste comes mainly from the northern hemisphere, oceans in the southern hemisphere are almost equally polluted, the study says.