You're listening to SHORT WAVE from NPR.

Hey, everyone. Today we are welcoming Laura Sullivan, NPR News investigative correspondent, longtime truth teller, first-time SHORT WAVE guest. Welcome to the show. How are you?

LAURA SULLIVAN, BYLINE: So good to be here. Doing great.

KWONG: So we're talking today about recycling, the science of what happens and doesn't happen with those peanut butter jars and yogurt containers lovingly placed in blue bins. I know this life, but I don't know much about how it all works. Laura, before you started investigating recycling, did you partake in it?

SULLIVAN: Oh, I mean, grew up recycling. I mean, we were drawing the recycling symbol, you know, with the three arrows in kindergarten, taping them all over the school. And, I mean, there were all these contests, I mean, who could draw the best blue planet with the chasing-arrows symbol all over it. You know, this wasn't some instructional PSA. This was, like, a lifestyle.

KWONG: Yes. I can totally picture a little Laura diligently...

KWONG: ...Drawing these arrows and following these rules.

KWONG: A good kid recycles.

SULLIVAN: I mean, recycling makes people feel good. You know...

SULLIVAN: ...You feel like a responsible steward of the Earth. We feel very small when it comes to global change. But every time we throw something in a recycling bin, we feel like, well, at least we did something. You know, we did our part. I put it in the bin. And, you know, we feel this way because this is what we've been told for decades now.

UNIDENTIFIED PERSON: The bottle may look empty, yet it's anything but trash. It's full of potential...

SULLIVAN: This feel-good message that through recycling, we can save the Earth.

UNIDENTIFIED PERSON: We've pioneered the country's largest, most comprehensive plastic recycling program to help plastic fill valuable uses and roles instead of filling valuable land. At DuPont...

KWONG: Wow. So if that is what we've been told for decades, Laura, what is the reality?

SULLIVAN: OK. The reality is recycling plastic is not a personal empowerment magic bullet, and it never has been. The latest environmental figures reveal less than 6% of all plastic is ever turned into anything else. I mean, that commercial was from 30 years ago. And this number keeps dropping each year the more plastic is produced. So we're going in the wrong direction 30 years later. And then you got to look at the other issue here, which is that plastic can only be recycled into something else once or twice before these chemicals break down. So at best, it's, you know, a one- or two-stop bus on the way to the landfill.

KWONG: Why was everyone told, then, to recycle plastic 30 years ago if you're saying, scientifically speaking, the most you can do is maybe one or two other products with the plastic afterward?

SULLIVAN: The oil and gas industry. Yeah, these ads, this sort of barrage of public messaging came from the oil and plastic industry. And they spent tens of millions of dollars telling people not only about the amazingness of plastic but also - and here's the real catch - that it was the public's responsibility to recycle it. But top industry officials always knew it was near impossible to turn all that plastic trash into new plastic items. And we found all these internal industry documents from the 1970s and '80s where they were telling each other that plastic recycling is problematic and infeasible and unlikely to work on a large scale.

KWONG: Today on the show, Laura Sullivan's two-year investigation into the difficult chemistry of recycling plastics. Many places offer recycling services, but only a small fraction of old plastics ever become something else. I'm Emily Kwong. And you're listening to SHORT WAVE, the daily science podcast from NPR.

KWONG: So, Laura, I want to get subatomic with you in this episode. I've sorted all kinds of plastic in my life, gone to great lengths to get it clean and recycled, been shamed...

KWONG: ...By roommates for not washing out my containers.

SULLIVAN: Hundred percent, hundred percent.

KWONG: ...But I've never really considered plastic on a chemical level. What is it?

SULLIVAN: So - all right, let's take aluminum, right? It's an element. It naturally occurs on the Earth. You can melt it or heat it or smush it, and it's still going to be aluminum. This is not the same. With plastic, if...

SULLIVAN: ...You break plastic down, you get oil and gas. This makes it less stable. So plastic is really just a series of molecules strung together into something called polymers. There's going to be a test on this after. And after - and if you add molecules going in one direction, you're going to get a plastic called Styrofoam. If you add the molecules in another direction, you're going to get a plastic called Saran wrap. If you go another direction, you're going to get a plastic water bottle. It just depends on how you string all these different molecules together.

KWONG: OK. So it's, like, a polymer-based, choose-your-own adventure...

KWONG: ...When it comes to plastic material science. That is....

SULLIVAN: Yes. That is what it is.

KWONG: And also sounds like a recycling nightmare.

SULLIVAN: It is, exactly - because none of these classes can be melted down together. I mean...

SULLIVAN: ...They're like oil and water, right? So sure, you can melt your yogurt cup into a blob with your water bottle. I mean, you could even make a giant blob. But who's in the market for a giant blob? It doesn't do anything.

SULLIVAN: And if you try to reform the blob into something helpful or useful, like a bottle or shoes or something, I mean, the molecules are going to revolt, and they're not going to hold together. Don't even try to put a food-grade item into something like that. You know, to make new plastic out of trash, you've got to have a pure pile of just one kind of plastic, one kind of polymer. And it has to be uncontaminated and clean. And you need a lot of it, I mean, sorted out from all that other plastic.

KWONG: OK. So if that is the case, did the earliest recyclers know that? And how did they plan to tackle that?

SULLIVAN: Well, in the beginning, in the 1950s, there were really just a couple kinds of plastic. I mean, these were the workhorses, you know, the milk jugs and the bottles. These were, like, the original plastics. You know, but humans, being as industrious and creative as they are, you know, kept adding molecules and coming up with all these new plastics. And there's now thousands of plastics. And even the recyclers can't tell them apart. Even, you know, like those red Solo cups - they look exactly the same. But some are made of one plastic, and some are made of another one.

KWONG: Yeah. But some do look different. I mean, a soda bottle definitely looks different than plastic wrap.

SULLIVAN: So true - but you have to think about this in terms of fast and cheap, right? These things are flying by on a...

SULLIVAN: ...Sorting machine, and a human has to make that call. And every second is costing money. And then so much of the plastic containers are now layered plastic.

SULLIVAN: I mean, who's going to pull all these layers apart? Why would anybody pay to do that? I mean, you can just go get oil and gas and make brand-new, virgin plastic really cheaply.

KWONG: I mean, I can fully appreciate this on the sorting side when I think about people actually doing this work at the recycling centers. But on the consumer side, if you turn the plastic over, though, isn't there a number stamped on the bottom? What's the point of those numbers?

SULLIVAN: The numbers on the bottom of your plastic container, which the plastic industry put there - they go like this - so, like, number one is soda bottles. Number two is milk jugs, also detergent bottles, like a Tide bottle. Three is PVC - think of hard plastic. I always think of, like, a cafeteria tray. Four is bags and bags - every kind of bag you can think of. Five are yogurt cups, strawberry containers, take-out containers. Six is Styrofoam. And seven is everything else.

KWONG: Everything else - seven is everything else.

KWONG: What does that even mean?

SULLIVAN: It means that it's all other plastic in the world that has ever been or will ever be created. (Laughter).

KWONG: That strikes me as problematically broad.

SULLIVAN: Just having seven numbers suggests this sort of nice harmony to plastic. But if you look at China, which produces so much of the plastic we consume, they actually do label their popularly used plastic by number in their factories. And they're up to 140. And this is before the manufacturers do fancy things to them, which add hundreds, if not thousands of more different kinds of packaging.

KWONG: The statistic we mentioned earlier, that only roughly 6% of plastics are getting recycled right now in the United States, comes from a new report from Greenpeace. It's not a lot, but it sounds like some of them are getting turned into new things?

SULLIVAN: Yes. So it's just this small percentage.

SULLIVAN: And your best shot is, really, these number ones and twos, you know, your soda bottles and your jugs. But there's no data on what percent of the jugs get a new life. And the soda...

SULLIVAN: ...Bottles - the numbers are not great. I mean, soda bottles are the gold standard of recycling. These are...

KWONG: Because they're so clean?

SULLIVAN: ...Because there's so many of them.

SULLIVAN: They're relatively clean, and they're easy to grab off a sorting line, right? But if you look at all these bottles that are produced every single day, less than 30% of all these bottles end up in recycling facilities. And they're mostly coming from curbside recycling programs or states that have deposit bills, where they give you 5 or 10 cents when you bring your bottle back.

KWONG: Yeah. OK. So if you have soda bottles as the gold standard and only 30% of them are showing up in recycling facilities, what is happening to them?

SULLIVAN: And so, OK, can we count on the 30% being turned into...

KWONG: ...Trying to be a recycling optimist here.

SULLIVAN: No, no, we cannot.

KWONG: And you're crushing it.

SULLIVAN: No, we cannot count on this 30% because....

SULLIVAN: ...The numbers start dropping real quick. The industry's recycling group acknowledges that they lose 15% of those bottles at the facility for one reason or another.

SULLIVAN: Mostly because they got contaminated or they're just not the right kind of bottle or turned out they're not what they're looking for. And then, when they go to be processed into what's called plastic flake, they lose another 30% on top of that. So now we're hovering down around the 50% range.

KWONG: The ones that do somehow make it through all of these hurdles and make it to the stage of becoming plastic flake, what happens to them?

SULLIVAN: OK, this the most important question of all because even if you can save those molecules, almost half of bottles go to things that will only have one new life. The easiest thing to do with those polymers is to turn them into fibers. So that means they're going to become carpets, a jacket, a textile. And that is the end of the recycling road, in terms of breaking the molecules down for reuse. They cannot be recycled again.

KWONG: How widely acknowledged is this by the plastics industry?

SULLIVAN: The plastic industry says that their mission is to recycle all the plastic they produce by 2040 - all the plastic that they produce.

KWONG: Even though the upper amount they've ever been able to recycle in the U.S. is about 10%?

SULLIVAN: Is 10% - that's their crowning achievement of recyclability after 30 years of launching recycling programs and all of this education and everything else - is 10%.

KWONG: How do they justify that when the science says completely otherwise?

SULLIVAN: They say that they are going to have better machines, better equipment, better science behind it and that they may chemically recycle it, which means burn it, right? And they're going to burn it for energy. There's enormous environmental problems with burning plastic for energy, and they have yet to be able to successfully do this in an economical way.

KWONG: How has learning all of this changed your perspective?

SULLIVAN: I go into the grocery store and feel nothing but defeat, you know? You try to wrap your brain around, what do we do, right? How do we slow this giant movement in the growth of the plastic industry, which the oil and gas industry is counting on to carry them out of a future when people are no longer using oil and gas for cars and transportation? This is the new profit center for them. I mean, the thing that people just sort of, I guess, should understand is that, you know, yes, try to recycle your soda bottles and jugs. Give it a shot. Hope for the best. You know, and support the deposit bills, where states will give 5 or 30 cents refunds when you bring them back.

The few states that have these bills, like Michigan and Oregon, have really held down the fort for the plastic bottle recycling situation. This is a tough road, though. The plastic industry and the beverage industry have fought these bills for decades. But the other solution is just knowing what you're holding in your hand. Throwing plastic into a blue bin is not going to save the world after all, you know? But finding a reusable product that you maybe could have used instead, well, maybe that just might.

KWONG: Laura, thank you so, so much, for helping us wrap our brains around this bigger picture of what plastics are...

SULLIVAN: Absolutely. This is so fun.

SULLIVAN: Love talking about this stuff.

KWONG: We have dropped some links to Laura's latest reporting and her full series on plastic waste in our episode notes. Definitely check that out.

KWONG: This episode was produced by Rebecca Ramirez. It was edited by Gisele Grayson and fact-checked by Abe Levine. Brendan Crump is our podcast coordinator. Our senior director of programming is Beth Donovan. And the senior vice president of programming is Anya Grundmann. I'm Emily Kwong. We're back with more tomorrow on SHORT WAVE, the daily science podcast from NPR. Thanks for listening.

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