Sorting Out Your Recycling Questions
Have you ever wondered whether your milk carton caps can be recycled? Or what happens to your recycling after it gets picked up from your curb? Science Friday video producer Luke Groskin decided to explore the mysteries of recycling further. He visited a recycling facility in Brooklyn and came back to report on it.
According to Groskin, the inside of a recycling facility looks like it might look like if you were “inside the digestive track of a robot that eats recyclables. It’s really really mechanized.”
And the smell?
“It was musky,” Groskin says, “but mostly the overriding smell, the smell that pervaded everything, was the three-day-old beer smell.”
Darby Hoover from the Natural Resources Defense Council says the U.S. falls somewhere in the middle of developed countries in terms of how well it does at recycling.
“In the U.S., we’re recycling about 34.3 percent of what we throw away at the municipal level,” Hoover says. “We’re not doing that well. We’re recycling about a third of what we dispose of. That puts us about halfway in between other developed countries. In Europe you’ve got countries that are doing much better — over 60 percent. Some of the rest of the world is doing a little bit worse, we’re right about in the middle worldwide.”
When it comes to specific questions about what can and cannot be recycled, Hoover says the answers vary depending on where you live.
“Anything that we talk about being recyclable or not recyclable has to be caveated by saying you should go to the website of your local city government and check to see what is accepted for recycling in your community and how they like to prepare it,” she says.
1. When it comes to greasy pizza boxes, though, there’s a pretty widely accepted rule-of-thumb.
“For the most part, communities don’t want pizza boxes in the recycling. If you’ve got paper that has grease or oils in it, that can complicate the paper recycling process. It’s hard to remove the oils from the fibers, so for the most part you can’t put those pizza boxes in with your other paper recycling.”
2. Some people wonder what the numbers surrounded by a triangle of arrows that are printed on plastics mean. Hoover says it’s a system that may or may not be helpful in in trying to determine whether or not a certain material can be recycled.
“You’ll see it on the bottom of almost every plastic container. … Most people look at that and think, ‘Well, that means it’s recyclable.’ It doesn’t,” Hoover says. “All it does is tell you what type of plastic it is. It’s there to just help identify the polymer but it’s not something that for the most part can tell you if it’s actually recyclable in your community or not.”
3. For those who might be agonizing over how much they need to fully rinse out or scrub their recyclables, Hoover says not to worry.
“You’re going to not be surprised that I’m going to say the answer varies from community to community,” Hoover says. “You want to get it as empty as you can, practically speaking. If you can use a little excess dishwater to shake it up and get it a little bit cleaner, that’s great. You don’t have to have it be sparkling clean. The issue is less usually with contaminating that container itself and more about having that food or that beverage that’s in the container transferred to paper and other materials in the recycling bin that then become contaminated.”
Recycled material doesn’t just end up at recycling facilities, however. Hoover says the recycling facility is just the first stop for recycled materials. After the plastics, papers and glass get sorted, they’re then loaded onto trucks to be sold and shipped to others who will further wash them, clean them, break them down and turn them into new products.
“A lot of our plastic recycling does get shipped overseas to China and other countries,” Hoover says. “That’s part of a global market for recycling and that’s true for many of our materials. Wastepaper is one of our largest exports from the U.S.”
—Elizabeth Shockman (originally published on PRI.org)
Darby Hoover is a senior resource specialist at the Natural Resources Defense Council in San Francisco, California.
Luke Groskin is Science Friday’s video producer. He’s on a mission to make you love spiders and other odd creatures.
IRA FLATOW: This is Science Friday. I’m Ira Flatow. When you’re sorting out your recycling, if you’re like me, you have a lot of questions. Can you toss hangers into the bin? It’s metal. Do I need to separate out my yogurt cups? Should I wash them first? I know you have thought about that one. What about the bottle caps? Where do they go? Should you keep them on the bottle, separate them?
But my biggest question is when I’m done separating everything and the truck comes to the take it all away, where does it all go? What does it look like in the bin, where they go to the giant plant? The cans, the hangers, are separated out from the plastics, all that stuff.
Well, Luke Groskin, our video producer has answered that question. He’s here to tell us all about that because he took a tour of the Sims Municipal Recycling Facility right here in Brooklyn. Welcome, Luke.
LUKE GROSKIN: Hi, Ira.
IRA FLATOW: That must have been fun. You visited– it takes in all sorts of glass and plastic from five borrows. That’s a lot of stuff, isn’t it?
LUKE GROSKIN: Oh, yeah, it’s upwards of 800 tons a day. That’s a lot. I mean, that’s hard to even conceptualize. What does that look like? Well, it looks like an 80 foot tall mountain of trash, of black, white, green, rainbow colored trash. And when you get up close to it, it’s all those mixed recyclables, as well there’s a whole bunch of other stuff that probably shouldn’t be there as well.
IRA FLATOW: Well, my vision is that you have a lot of people standing next to a conveyor belt grabbing at things.
LUKE GROSKIN: Oh, no. For the most part, that’s not what it really looks like. I liken it more to being inside the digestive track of a robot that eats recyclables. It’s really, really mechanized. There’s lots of conveyor belts. There’s machines that sort for metal. That’s a large spinning drum that has an electromagnet inside of it.
There’s machines that sort out flat objects, like paper or plastic, from the bottles and cans and things like that. There is disk shredders that break up glass. There’s even these optical sorters, which are really, really cool. What those do are basically they take a picture of an item underneath them, and they can actually tell the chemical composition of the item. And as the item passes over a little gap, a little air jet shoots it off, if it’s something that is made of PET, or HPT, or wood, or any other sort of material.
IRA FLATOW: It’s got to be lightweight so it can shoot it off?
LUKE GROSKIN: Yeah, it just fires it right off. And it goes onto another conveyor belt. And there’s conveyor belts, after conveyor belts, after conveyor belts. And they all lead to what looks like an extruder of recyclables, of all of one material. And they all get bailed up and turned into these big blocks.
IRA FLATOW: And then is there a market for them once they’re in these big blocks?
LUKE GROSKIN: Yeah, they all get put onto trucks, and sold, and shipped to people that are then going to break them down even further, wash them, clean them, and turn them into further plastics and things like that.
IRA FLATOW: I’m afraid to ask this question because it’s radio and it’s not smell-o-vision. What did it smell like?
LUKE GROSKIN: It smelled– it was musky. But mostly the overriding smell, the smell that pervaded everything, was the three-day-old beer smell. So you have mayonnaise and tomato whatever, you have all sorts of organics, as they call it, and they all kind of ferment. And then there’s of course lots of beer. And beer, I think, is the universal smell donor. It just pervades everything. So everything just smells kind of like three-day-old beer.
IRA FLATOW: It’s a great video. And video it’s on our website, sciencefriday.com/recycle, and you can see all these great machines working. But in the video you mention that there is one bane of the whole recycling system, something that gums up the works.
LUKE GROSKIN: Oh, yeah, especially in New York City. So a lot of people live in high rises. And those people have garbage shoots. And they don’t collect big baskets or boxes of recyclables. So they put them in tiny little plastic bags. And then sometimes they decide, oh, those plastic bags are recyclable, right? So I’m going to put plastic bags inside the bag in the first place. And then they put that inside of another plastic bag.
IRA FLATOW: A bag of bags.
LUKE GROSKIN: You have a bag of bags inside of bags and that just gums up everything. It’s a recycler’s nightmare because every day they have to stop the machines and detangle all the bags.
IRA FLATOW: Wow. I’ve heard about the bags. Get paper then, right? Paper or plastic, go for the paper. Luke Groskin is our video producer and he toured the Sims Municipal Recycling Facility in Brooklyn. And you can watch the video on our website at sciencefriday.com/recycle. It’s a great video, Luke, as always. And fun to watch.
LUKE GROSKIN: Thank you.
IRA FLATOW: I learned a lot from that one. We put on a tweet to test the waters to see if you all out there had recycling questions. And it turns out, sure, you’re all very curious about what happens to your bottles and cans.
Our next guest is here to sort out all of your reducing, reusing, and recycling questions. Darby Hoover, senior resource specialist at the Natural Resources Defense Council in San Francisco, and former recycler working in a recycling center. Welcome to Science Friday!
DARBY HOOVER: Thank you. Thank you for having me.
IRA FLATOW: You’re ready to take questions from our audience?
DARBY HOOVER: You bet!
IRA FLATOW: OK, let me ask you a couple of questions first. We have bins at home and on the sidewalk, but how good are we at recycling? How much of the waste actually makes it to the recycling plant?
DARBY HOOVER: In the US, we’re recycling about 34.3% of what we throw away at the municipal level. So we’re not doing that well. We’re recycling about a third of what we dispose of. That puts us about halfway in between other developed countries. So in Europe, you’ve got countries that are doing much better, over 60%. Some of the rest of the world is doing a little bit worse. We’re right about in the middle worldwide.
IRA FLATOW: All right, let’s go to the first question from San Mateo, California. Evan, welcome to Science Friday.
EVAN: Hi, thanks for having me. Question is, I know that regular cardboard is recyclable, however I was told that, especially with pizza, once you get the pizza home and the oil drips off into the box, it contaminates the box itself and renders the cardboard from the pizza box not able to recycle. Is that true?
IRA FLATOW: Good question, Darby?
DARBY HOOVER: It is pretty much true. And I will just start by saying that what is recyclable varies from community to community. So anything that we talk about being recyclable or not recyclable has to be caveatted by saying, you should go to the website of your local city government and check to see what is accepted for recycling in your community and how they’d like to prepare it.
But for the most part, communities don’t want pizza boxes in the recycling. If you’ve got paper that has a grease or oils in it that can complicate the paper recycling process. It’s hard to remove the oils from the fibers. So for the most part, you can’t put those pizza boxes in with your other paper recycling.
IRA FLATOW: Let’s go to Lauren in West Orange, New Jersey. Hi, Lauren, welcome to Science Friday.
LAUREN: Hi, thanks, Ira. Thanks, Darby. I’ve expressed with envy to a friend of mine in a neighboring town that they recycle Styrofoam. So I’ll bring my Styrofoam from my town over to their town where I work. And he kind of laughed at me and said, well, we just stick it on a boat and send it to China and then it gets buried somewhere. So I don’t know if there’s any truth– I don’t know what happens with Styrofoam for those towns that do say they recycle it.
IRA FLATOW: Yeah, what happens to Styrofoam?
DARBY HOOVER: Styrofoam is actually a trade name for expanded polystyrene foam. And that polystyrene foam can take many forms. It can be that kind of big packaging that surrounds things like electronics. It can be those little peanuts that come into other kinds of packages when you get them shipped to you. And for the most part, it’s air. It’s got very little material in it. And it’s a very large portion of air. What that means is, it’s not very cost effective to pick up and take somewhere to recycle it. Because you’re transporting primarily air. And once you get it somewhere where you can recycle it, you have to compress it down into a very small little brick so that it’s more economical to ship somewhere to recycle.
That said, it can theoretically be recycled. But because of those challenges of the economics and of it being lightweight and therefore very easy to become litter, many communities don’t want to have Styrofoam in part of their waste stream. So the communities that do recycle it are taking it, compressing it down, and selling it to other buyers. It’s also true that a lot of our plastic recycling does get shipped overseas to China and other countries. That’s part of a global market recycling and that’s true for many of our materials. Wastepaper is one of our largest exports from the US for [INAUDIBLE].
IRA FLATOW: Here’s a tweet from @tweedledee, who says, plastics used to make clear containers to hide the bruised fruit, are these containers recyclable?
DARBY HOOVER: That’s going to depend on your community. So if you’ve got hard, rigid plastics in New York, for example, you can put any hard, rigid plastic in your recycling bin. That’s also true in San Francisco. Most communities don’t take flexible types of plastic for recycling, partly for the reasons Luke noted earlier, that they tend to jam up the recycling equipment. But you do have to check city by city to see what’s acceptable in your particular community.
IRA FLATOW: What about those triangles at the bottom with the numbers on them? How do you make head or tail of what they’re for, and how to use them?
DARBY HOOVER: So on plastic containers, you’ll see on the bottom of almost every plastic container, a little triangle that looks like chasing arrows with a number inside it. Most people look at that and think, well, that means that there it’s recyclable. It doesn’t. All it does is tell you what type of plastic it is. So the number says, if it’s number 1, it’s PET plastic, number 2 HDPE, and so on. Number 7 just means other, so it’s everything that doesn’t fit in those first six categories.
So all that does is say this is the type of plastic it is. You’ve still got to go and check with your city to see if it’s recyclable in that city. And even then, some cities will further break it down and say, you might be able to recycle number 1 and 2s plastics, but only if they’re bottles and not tubs. Because the difference in shape actually reflects the difference in processing that changes the melting point and means you can’t recycle them together. So there’s all these technical challenges with plastic.
IRA FLATOW: So why do we even have the number and the triangle on the bottom if we can’t use it?
DARBY HOOVER: [INAUDIBLE] put it there to just help identify the polymer. But it’s not something that is, for the most part, can tell you if it’s actually recyclable in your community.
IRA FLATOW: [MUMBLES]. OK, let’s go to Steve in [? Malden, ?] Massachusetts. Hi, Steve.
STEVE: I’ve got to run, Pat.
IRA FLATOW: You’ve got to run, Steve. You’ve got to get on the radio.
STEVE: I’m sorry. Hello, Ira. I love your show. And thank you, Darby. I play a lot of tennis.
IRA FLATOW: Me too.
STEVE: The balls come in a can, they’re plastic cans with a metal ring around the top. Are they recyclable? And also, what about the balls? I hate throwing them away.
IRA FLATOW: Get a dog. No, that’s what we do. I’m sorry. Go ahead. Yeah, what do you do with those?
DARBY HOOVER: There are actually some organizations that will take things like used tennis balls and repurpose those. So I would suggest just googling for the area you are in to see, if you have a large quantity of those, can those be taken to those organizations? And then the cans themselves are an example of a composite material. So they’ve got aluminum. They’ve got fiber. They’ve got plastic. One way to recycle that is to separate all those components.
Another way to recycle it is to work with an organization, like a tennis club, or a sports organization, that may be able to collect them in volume and take them back to a particular processor who can have a set up that can manage those. So we did actually do that with the USTA a few years ago. We were able to collect a large number of tennis ball cans for recycling, specifically from the USTA, and work with Sims to get them recycled in New York City. But that was something that’s not typically available for your average consumer.
IRA FLATOW: Oh, there you go. Let’s go to St. Louis and to Donna. Welcome, Donna, to Science Friday.
DONNA: Hi, thank you. Glad to be here. My question is about the packaging materials that we’re getting a lot more of these days, like in Amazon deliveries at the door, or whatever. Where in the past, we were getting all the little Styrofoam peanuts and then it went to some sort of corn based type of material, which was great because you could get rid of that easily by watering it down. Now they’re using the thin plastic bubbles. Some of it’s the small kind that you can pop, the little itty bitty bubbles. But some are the larger bubble, air pocket-y things.
IRA FLATOW: Like a pillow. Yeah, those big little pillows.
DONNA: Yeah, they’re like little pillows. Yeah, those are great. I love them and I reuse them. But, if I’m done using them, can I pop them and put them into the same container that I put, let’s say, some plastic bags from the grocery store, or something that comes in a plastic bag itself, like a new item in the mail that I get, like an outfit or something?
IRA FLATOW: Let’s get an answer, a great question. Darby?
DARBY HOOVER: It is a good question. So plastic film, again, is not typically accepted in most curbside recycling programs. But many grocery stores and other similar community outlets do accept plastic bags and other kinds of plastic film for recycling. What they accept varies, again, by community. Some of them will take that kind of plastic film. A lot of them will just take straight up plastic bags.
I love the idea of you reusing it. That’s of course the highest and best use for something that you get like that, to see if you can repurpose it another time. And I would also just note that one way they could reduce the environmental impact of those is to include recycled content so that the plastic air bubbles are themselves using less material because they’re largely air, but that material that is plastic could be made from recycled content, further reducing the footprint.
IRA FLATOW: I’m Ira Flatow. This is Science Friday from PRI, Public Radio International. I’m talking with Darby Hoover, senior resource specialist at the Natural Resources Defense Council, and former recycler. What do you do with batteries? There’s so many batteries everywhere, batteries and CFLs, the compact fluorescent light bulbs.
DARBY HOOVER: Yeah. These fall into the category of something called household hazardous waste. So those are not things that you’re going to want to put in your recycling bin, and they’re typically not things that you should put in your bin that goes to the landfill either. Those are typically treated separately to make sure that any hazardous components are kept out of the usual landfill.
So most communities are doing some form of battery recycling. In many communities you have drop off areas at hardware stores, libraries, and other facilities where you can take batteries. In the community where I live, in Oakland, California, you can take batteries and put them in a Ziploc bag and put them on top of your trash collection container, and they’ll pick them up and take them to recycling. There’s also in many places, household hazardous waste drop off centers, collection events, and a lot of different ways to get batteries back to the right place for recycling.
IRA FLATOW: Let’s go to the phones. Let’s go to Daniel in Brighton, MA. Hi, Daniel.
DANIEL: Hi, Ira. Thanks for taking my call.
IRA FLATOW: You’re welcome. Go ahead.
DANIEL: Yeah, my question is how important is it to rinse out your peanut butter jar, or your jar of sour cream, before you put it in the recycling? And is it really worth it if you’re wasting all that water to rinse it out?
IRA FLATOW: Ooh, good question.
DARBY HOOVER: That is a great question. You’re going to not be surprised that I’m going to say the answer varies from community to community. The official guidance from the city of New York is to rinse containers before recycling. In California, since we’re conscious of being in drought conditions, we’re less encouraged to rinse out containers and more encouraged to scrape out or wipe out a container before recycling.
So you want to get it as empty as you can, practically speaking. If you can use a little excess dish water to shake it up and get it a little bit cleaner, that’s great. You don’t have to have it be sparkling clean. The issue is less usually with contaminating that container itself, and more about having that food or that beverage that’s in the container transferred to paper and other materials in the recycling bin might become contaminated. So usually it’s not a hard thing. If you’ve got glass or metal that’s got food in it–
IRA FLATOW: Scrape it out.
DARBY HOOVER: That doesn’t [INAUDIBLE] but it does affect the paper.
IRA FLATOW: Now let’s go to last question to Jim in Griffin, Georgia. Hi, Jim.
JIM: Hey, hello. One of the callers already asked a question about the grocery bags. I was curious whether or not they actually got recycled? Seems like I remembered hearing that there was a big hoo for haw of them not necessarily being recycled but being thrown in the trash.
So if you don’t mind, I’ll ask a different question. If retailers aren’t responsible– if the people that aren’t profiting from things that are difficult to recycle don’t take a hand, aren’t made to take a hand in it, what about stuff like propane cans? And you buy a lot of different things from retailers, and they’re profiting. And then you’ve got this thing that’s going in the landfill. It seems like there should be more pressure on the retailers to take a hand in and get it done.
IRA FLATOW: Quickly.
DARBY HOOVER: I completely agree with you. In other countries there are producer responsibility laws, where producers of the items that most commonly end in the garbage are required to finance, and in some case, provide logistics for recycling those materials. We could have those kinds of laws in the US. We have them already for things like paint, and batteries, and carpets.
But we need to explore the opportunity of extending those laws to packaging, so that we bring that sector more into the responsibility for what happens to the materials they produce after they’re disposed of.
IRA FLATOW: All right, thank you, Darby. Great stuff. Darby Hoover, senior resources specialist at the Natural Resources Defense Council in San Francisco. And you can watch our video of the inside tour of the Sims Municipal Recycling Center in Brooklyn. It’s on our website at sciencefriday.com/recycle, a great little video.
We’re going to take a break. And afterwards we’re going to come back and look how racism can affect mental and physical health, and talk with a scientist who is designing a virtual reality experience to let us walk in other shoes. Stay with us.
Alexa Lim was a senior producer for Science Friday. Her favorite stories involve space, sound, and strange animal discoveries.