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Suppose you took a slice of the Atlantic Ocean, like a slice of pie, and found how much plastic is in the water. NPR's Rebecca Hersher reports on people who did that.
REBECCA HERSHER, BYLINE: Humans love plastic. And when our toothpaste tubes and surgical masks and car fenders reach the ends of their relatively short lives with us, they begin the rest of their very long lives as trash. And a lot of that plastic pollution is really tiny, some too small to see with the naked eye.
KATSIA PABORTSAVA: Nature does its job.
HERSHER: Katsia Pabortsava is an ocean biogeochemist at the National Oceanography Center in the U.K. And she says the ocean is really good at making big pieces of plastic small.
PABORTSAVA: You have sunlight that breaks down the plastics. You have wave action. You have abrasion.
HERSHER: And those tiny bits eventually make it back to us humans in our air, our water and our food. But scientists still don't know exactly how much so-called micro plastic is in the ocean. There have been rough estimates.
PABORTSAVA: It was about, I think, between 5 and 12 millions tons went into the global ocean just in 2010.
HERSHER: But when scientists added up all the plastic on the surface of the ocean, there was a lot less than they expected, which Pabortsava says is not good news. It just means it's somewhere else.
PABORTSAVA: If we're missing 99% of the plastic that we thought we have put in, it has to be somewhere. And previous studies indicate that there is a lot of plastic that is present at the seabed already.
HERSHER: And if there's plastic on the surface and all the way at the bottom of the ocean on the seabed, there's probably plastic in between. So Pabortsava's team gathered water from the top 200 meters of the Atlantic Ocean to look for types of plastics that are used in packaging. And they found a gigantic amount of plastic hanging out below the surface, way more than the previous estimates would suggest. They published their findings in the journal Nature Communications. Pabortsava says it's bad news. For one thing, it's yet more evidence that animals are eating plastic.
PABORTSAVA: And as those small organisms are eaten up by bigger fishes, for example, which we ultimately eat, it means that human beings will be receiving a lot more contaminants.
HERSHER: The new study also suggests what many scientists have suspected for years, that humans are putting a lot more plastic into the ocean than we think we are and that plastic is staying in the water for a long, long time. Rebecca Hersher, NPR News. Transcript provided by NPR, Copyright NPR.