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Tiny particles of plastic are showing up all over the world, floating in the ocean, buried in soil, in food and even beer. NPR's Christopher Joyce reports on new research that reveals where a lot of that plastic is coming from.
CHRISTOPHER JOYCE, BYLINE: A lot of the plastic waste littering the planet escapes from garbage dumps and landfills. But new research in Germany has shown a surprising new source - organic fertilizer from food waste. Collecting food waste to make fertilizer is a big deal in parts of Europe and is catching on in the U.S. But Ruth Freitag, a chemist at the University of Bayreuth in Germany, says there's a problem.
RUTH FREITAG: What happens most of the time is people don't like to put their garbage into the bin as it is. They like to wrap it up, typically in a plastic bag.
JOYCE: The bags get processed along with the food. Freitag says some of the contamination also comes from plastic food wrappers as well. She can tell by the type of plastic they find. The research appears in the journal Science Advances. The team found plastic in food waste from both household and commercial sources. Freitag says the takeaway message here is that even environmentally friendly ideas sometimes don't consider the way people, even those with good intentions, actually live.
FREITAG: Some good ideas work but only when people are responsible.
JOYCE: Eventually, she says, the plastic gets washed out of the fertilizer that's spread on land and gets into waterways. That's where researcher Chelsea Rochman at the University of Toronto has been finding tiny pieces of plastic.
CHELSEA ROCHMAN: So if we move away from the ocean and we go upstream, there's evidence of microplastics in rivers and lakes and other freshwater bodies.
JOYCE: Writing in the journal Science, Rochman notes that she's found tiny bits of plastic in what comes out of sewage treatment plants, which can also be used as fertilizer.
ROCHMAN: The sewage sludge, for example, that we're spreading on the earth - a source of microplastics out into the environment - how are they interacting with animals and soils?
JOYCE: So far, there's no strong evidence that microplastics are hurting people. But it's clear they are making their way into the food chain.
ROCHMAN: We find it in our seafoods. We find it in sea salt. There's evidence now of it in drinking water.
JOYCE: Rochman says there's good news here, though. As people track the myriad pathways that plastic waste takes, the closer they are to cutting it off at the source. Christopher Joyce, NPR News.
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