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If you drink beer or water or eat fish, you may be consuming microplastic. This plastic waste, as its name suggests, is tiny. It's part of the tide of plastic trash littering land, oceans and rivers. As NPR's Christopher Joyce reports, scientists are trying to find out if it's a threat to animals and people.
CHRISTOPHER JOYCE, BYLINE: Lake Ontario sparkles on a sunny day, lapping at Toronto's park-lined shore. But the lake has a dirty underbelly, and that's what interests ecologist Chelsea Rochman. Rochman and her student Kennedy Bucci have come to the edge of an inlet that's covered with washed-up debris. An apartment building looms overhead. Rochman squats down and reaches into the muck with her bare hands.
CHELSEA ROCHMAN: I am digging...
KENNEDY BUCCI: I know.
ROCHMAN: ...And just finding more and more - like, whole bottle caps. This is insane.
BUCCI: It's so ingrained in the soil.
JOYCE: They're digging for small pieces of plastic and tossing them into a jar. Rochman is an ecologist and researcher at the University of Toronto. Her passion is to find where plastic waste is coming from and how it gets into the food chain, the chain that feeds us.
She inadvertently picks up something she wishes she hadn't.
ROCHMAN: That's why you have gloves on.
BUCCI: That's why I gave you the glove.
JOYCE: It is a dirty business, but Rochman has always loved cleaning up. She remembers how, as a child, she puzzled her parents by volunteering to clean house. In high school in Arizona, she got even more ambitious.
ROCHMAN: I used to take my friends into the desert and clean up a mile of trash every Earth Day. I remember finding weird old dolls and strange old toys that I thought were creepy but then I would also keep.
JOYCE: As a graduate student, she got a trip on a research vessel to visit the infamous floating garbage patch in the Pacific Ocean. She and the other scientists were supposed to count the plastic as it drifted by.
ROCHMAN: And so everyone runs up to the bow. And they're like - there's trash. There's trash. Everyone start counting the trash. And so we all start counting the trash. And we're looking. And it's, like, basically like a soup of confetti, of tiny little plastic bits everywhere. And everyone just stopped counting - like, sat there, like back up against the wall and just were like, OK. A, this is a real issue. B, it's not an island of trash you can pick up. And C, the tiny stuff, for, me was - as an ecologist, oh, this is really getting into the food chain. You can spend a whole career studying this stuff.
JOYCE: So she did, especially microplastic, pieces you can barely see. Consider that since the mass production of plastic in the mid-20th century, 8 billion tons have been manufactured. And when it's thrown away, it doesn't just disappear. Much of it crumbles into small pieces. It ends up in soil, in fertilizer, in rivers, lakes and oceans.
At one of Rochman's labs, Kennedy Bucci prepares to make her own microplastic from the morning's collection.
So what we have here is a coffee grinder and some ugly-looking black plastic.
(SOUNDBITE OF COFFEE GRINDER WHIRRING)
BUCCI: So this is the plastic that I feed to the fish to measure their effects.
JOYCE: That includes the tiniest fish, fish larvae. She's got a bunch in a beaker of water that also contains ground-up plastic particles. Under a microscope, the larva's gut is translucent. You can see right into it.
It's like a big teardrop with a fish stuck in it.
BUCCI: You can see kind of a line of...
BUCCI: ...Weirdly shaped black things. Those are the microplastics.
JOYCE: Yeah, I can see that. I definitely see that, two or three places.
UNIDENTIFIED PERSON: Oh, is it bad?
JOYCE: In another lab, the team keeps hundreds of grown-up fish in bubbling tanks stacked 6 feet high. They're fathead minnows. Bucci says they make good test subjects.
BUCCI: They just kind of end up eating whatever is floating around in front of them. So if you stick your finger in there, they'll all eat your finger.
JOYCE: They try. Luckily, they don't have teeth. But they don't need teeth to eat microplastic. It's like a soup in rivers and lakes and oceans, a chemical soup. Plastic can shed the chemicals it's made from. It also attracts other chemicals in the water that latch onto it, toxic industrial compounds like PCBs, for example. Tracking all those chemicals is researcher Clara Thaysen's job.
CLARA THAYSEN: So right now we're starting with the common types of plastic - so polyethylene, polypropylene, polystyrene. But there is tons. This happens all the time. You invent something that seems really great, and then you don't think. And we've become so dependent on it.
JOYCE: Rochman says testing what plastic does to the tissues of fish matters not just to the fish but to us.
ROCHMAN: We eat fish that eat plastics. So it's this question of, are there things that transfer to the tissue? Does the plastic itself transfer to the tissue? Do the chemicals associated with the plastic transfer to the tissue?
JOYCE: In fact, plastic does get into fish tissue - plastic fibers from clothing, for example. There's a lot in fleece. Rochman found fibers in fish from San Francisco Bay. She bought a washing machine for her lab and washed fleece clothing, and lots of fibers came out. And it's not just in the water. It's even floating in the air.
ROCHMAN: If you put a piece of double-sided sticky tape on the lab bench for an hour, you come back and it's got four plastic fibers on it.
JOYCE: So far, they do know that microplastic particles can sicken or even kill larvae and fish.
ROCHMAN: The things we don't know - what are all of the sources where it's coming from? - so that we can think about where to turn it off. And once it gets in the ocean, where does it go? - which is super important because then we can understand how it impacts wildlife and humans.
JOYCE: Rochman says she's ready to spend the rest of her career finding out.
Christopher Joyce, NPR News.
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