The Million-Dollar Toothpaste Tube

Season 2 • Episode 10

We’re overrun with plastic. It’s in our oceans, our water, our food. Something has to be done—preferably by corporations, which churn out millions of tons of plastic every year. 

Enter: the toothpaste tube. It might seem like a minor player in the plastic problem, but we throw 20 billion toothpaste tubes into the landfill every year. Recycling plants can’t take them, because they’re made of plastic and metal foil bonded together. They all end up in the landfill.

Colgate, the #1 toothpaste brand, decided to tackle the problem. It spent five years and millions of dollars to design a tube made of the same plastic milk jugs are made of—the easiest-to-recycle plastic in the world—with no metal foil. The new tube is indistinguishable from existing tubes—except the whole thing can go into the recycle bin. 

And then—Colgate gave away the patent. Today, 90% of the world’s toothpaste makers are switching to recyclable toothpaste tubes. This is the uplifting, surprising, and slightly hilarious story.

Episode transcript


After 65 years, we’ve pretty much mastered the art of making plastic. What we haven’t yet figured out—is what to do with plastic when we’re done with it.

GEYER: It lasts a really long time! It doesn’t biodegrade. So it just sits there.

Of all the forms of plastic being dumped into our oceans and our landfills, you might not think that toothpaste tubes are much to worry about. But you’d be wrong.

Greg: [00:03:42] So there are roughly 20 billion, with a B, toothpaste tubes produced every year. / most of them, or if not all of them, wound up in landfill.

That’s because you can’t recycle toothpaste tubes. Or at least you couldn’t—until Colgate spent five years and millions of dollars coming up with a recyclable tube—and then did something highly irregular with the patent. 

I’m David Pogue, and this is “Unsung Science.”

First Ad

Season 2, Episode 10: The Multimillion-Dollar Toothpaste Tube.

Can you imagine? Until the late 1950s, there was no such thing as plastic. My parents lived in a world before plastic. Maybe yours, too.

NARR: “The ingenious alchemy of coal and oil provides the material; ingenious machinery presses and stamps and molds the material into a wide variety of products!”

Plastic was cheap, sanitary, strong, light—and so durable, it could last forever. 

And that, actually, is the problem. We manufacture 460 million tons of plastic a year, and we recycle only around 9% of it. The rest goes either into the landfill—or someplace even worse: The ocean. Every year, 14 million tons of plastic ends up in the ocean.

ROLAND: 10:07:11 Plastic in the ocean has a tendency to break down into ever smaller pieces. And these tiny pieces then get taken up even lower down in the food chain. So we know that– it ends up on our dinner plates.

Roland Geyer is a professor of environmental science at UC Santa Barbara who studies how much plastic we throw away. 

DP: There’s plastic in my food?

ROLAND: There is plastic in your food. There is plastic in your sea salt. And there is plastic coming out of your tap. 

But even within the tiny fraction of plastic that we put into the recycle bin, 40% of it is contaminated—by food, or paper labels, or other materials. And therefore worthless. Recycling plants pull out that contaminated stuff and just throw it away. Send it to the landfill. 

We used to ship the unsaleable plastic to China, where desperately poor people would paw through it and try to find usable bits. But in 2018, the Chinese government decided it no longer wanted to be the world’s dumping ground, and the country stopped importing all our dirty plastic. Today, most of our dirty plastic goes into the landfill or the ocean. 

Now, at this point, you’re probably feeling pretty depressed. But hold on now. It’s about to get worse!

Even pure, clean plastic that you put into the recycling bin may get pulled out and thrown into the landfill! It’s true! Just because it has that little chasing-arrows triangle logo on it doesn’t mean it’s actually recyclable. 

Game-show music

Welcome to…“Can you recycle that?” The exciting game show where you realize how little you know about what gets recycled! 

Let’s begin with Round 1, for 100 points: #1 plastic. You look at the little chasing-arrows triangle logo on the package, and it says #1. #1 plastic. That’s what soda bottles and food jars are made of. Can you recycle that?

Ding ding ding ding ding!


Applause, cheers.

There’s a solid market for clean #1 plastic. In other words, there are companies willing to buy #1 plastic, to make into new things. 

How about #2 plastic? That’s milk jugs and detergent bottles? 

Ding ding ding ding ding!

YES YOU CAN! #1 and #2 are the good stuff. An impressive 30% of it gets recycled. 

Applause, cheers.

Well, relatively impressive.

But what if it’s BLACK plastic, like takeout bowls?

BZZZZZT! Crowd “awwwws” disappointedly

No, I’m sorry! Black plastic confuses the optical sorting equipment at most recycling plants—it all goes to landfill. Complain to your restaurants!

What about plastics #3, 4, 5, 6, and 7?

BZZZZZT! Crowd “awwwws” disappointedly

Nooooo! Some cities collect plastic 3 through 7, but virtually none of it actually gets recycled. It’s burned or landfilled. When a company puts that little Recycle Me logo on their #3, 4, 5, 6, and 7 plastics, it’s just a cynical ploy to make us think they’re good citizens. That’s called greenwashing!

You also can’t put plastic bags or plastic wrap into your recycling bin. It gums up the equipment at the plant! Fortunately, most big grocery stores will recycle plastic film.

Game-show music ends.

So you’re starting to grasp the scope of this problem. And to solve it, we have to do battle with lobbyists for the oil and plastic industries, who desperately do not want us to start using less plastic. 

But this much is for sure: We, the people, cannot solve the problem through individual action. Doing better at recycling won’t solve the problem. We need corporations to get involved. Like the ones that make…toothpaste tubes.

Greg: My name is Greg Corra. I’m Worldwide Director of Global Packaging and Sustainability for Colgate-Palmolive.

Stephan:        I’m Stephan Habif and I’m the chief technology officer here at Colgate-Palmolive.

Now, you might chuckle at the notion of sitting down with two toothpaste executives, at the idea that they might do something about the plastic crisis. But that’s only because you don’t appreciate the scale of the toothpaste-tube problem. 

Greg: So there are roughly 20 billion, with a B, toothpaste tubes produced every year. Most of them, or if not all of them, wound up in landfill.

20 billion is pretty bad, but it could get a lot worse. Because—and I hope you’re sitting down, thinking happy thoughts—it turns out that about 45% of the world’s population does not use toothpaste.

Also, 70% of the world does not use toilet paper. But that’s a different conversation. 

The point is,… 

Stephan: There is still way too many people in too many countries that either don’t have any oral hygiene or don’t brush their teeth with a fluoride toothpaste or don’t brush often enough.

He’s pointing out that all that un-brushed humanity could be a business opportunity for Colgate. These people could one day buy toothpaste! Or, to put it more kindly, 

Stephan: We have been addressing a major health crisis that is right under our nose. WHO has estimated that 45% of the world population is affected by oral disease. 

WHO is the World Health Organization. 

Stephan: So what we’ve been trying to do, we’ve been trying to make sure that everyone brushes twice a day with fluoride toothpaste, and that would improve their health. Because, by the way, oral health has been linked to systemic health issues like diabetes, like cardiovascular disease, etc. But in doing that, / we will increase the amount of toothpaste tubes that are being produced. So we also are concerned, obviously, about our planet and sustainability. 

So yes—Colgate does intend to spread its toothpaste to the vast unbrushed masses—but Colgate does realize that, as Spider-Man’s Uncle Ben put it, 

Ben: With great power comes great responsibility.

Pogue: Okay. So somewhere along the line, somebody internally at the company said, “Guys, we’ve got to do something about these billions of toothpaste tubes.”

Greg:  Yep. We needed to deliver a recyclable toothpaste package, right? And we called it a package, because we didn’t know at that time whether it would be a tube or not.  

So this goal was set before we knew there was even a pathway to a solution, and before we knew how much scale it could be. So that was the impetus with it starting. 

The year was 2014. 

Greg And we looked very broadly and really obsessed with the problem of why are toothpaste tubes not recyclable? Why is toothpaste even in the tube? What needed to be true to make them recyclable? It began five years of R&D work that went in a number of different directions.

I mean, really? What could possibly take five years? 

Well, the big problem is that every one of those 20 billion tubes a year is made of more than plastic. Every single one has an aluminum lining. So you can’t recycle it; there’s no machine on earth that can separate out the plastic from the metal foil. They’re bonded together forever.

Greg: And then because of that, they weren’t accepted by recyclers at scale anywhere.

Pogue: So if I were to take an empty toothpaste tube, cut it in half, I would see that the inside is actually reflective shiny metal?

Greg: For today’s conventional tubes, yes.

OK, so…why not just get rid of the metal lining? Then boom—people can toss the plastic tube into the recycling bin.

Well, the metal lining is there for the same reason potato-chip and snack bags have metal linings: To lock in freshness. 

Greg: What that metal layer is doing for you, it’s a barrier—oxygen, flavor, many things. And you get the plastic for performance, the metal for barrier. 

I kind of giggle every time he uses the word “performance” when we’re talking about… a tube of toothpaste. But he means all the things we want from a toothpaste tube:

Greg: By performing, we need it to protect, be hygienic, and all of those things, from squeezability to heat resistance and other things. 

And above all—preserve the flavor.

Greg: Colgate is very focused on the performance of flavors. For many of our brands, people have been brushing their teeth with it their entire life. So the flavor profile couldn’t change. I would say of that five-year R&D process, it could have been about a year shorter had we not paid such attention to the flavor. 

Now, remember: Pretty much the only kinds of plastic we universally recycle in this country are #1 and #2. So it seemed pretty clear to Colgate that the new tube would have to be made of #1 or #2.

The technical name for #1 plastic is PETE, or Polyethylene terephthalate. Yeah, there’s a P-H T-H in there. Terephthalate. The soda-bottle plastic.

And the full name of #2 plastic, the milk-jug plastic, is high-density polyethylene, fondly known as HDPE. 

Greg: And when we look at recycling, HDPE is one of the two main recycling streams that are in practice and at scale globally. When we embarked on this, our target was a scaled, viable recycling stream. 

Pogue: This idea about let’s, “let’s make it mostly of HDPE,” how long through the process did that idea come up with?

Greg: Not right off the bat. So we knew what we were targeting, but we didn’t yet know how to get there.

Especially because #2 plastic alone couldn’t maintain the flavor and freshness of the toothpaste. The tubes still needed a lining—it just couldn’t be metal anymore. So…

Greg: So we needed to re-engineer the entire tube to be mostly out of a single material, to replace the flavor barrier with a new material that’s compatible with HDPE. So we took the aluminum foil out, we brought in a material called EVOH, which is a plastic compatible barrier. 

EVOH stands for Ethylene-vinyl alcohol copolymer. EVOH. You’d think you’d say it “EEE-vo,” although I guess that would sound too much like EVOO—you know, extra-virgin olive oil. You wouldn’t want to make your salad dressing with EVOH.

Anyway, here’s what Wikipedia says about EVOH: It’s a “plastic resin commonly used as an oxygen barrier in food packaging. It is better than other plastics at keeping air out and flavors in, is highly transparent, weather resistant, oil and solvent resistant, flexible, moldable, recyclable, and printable. Its drawback is that it is difficult to make and therefore more expensive than other food packaging.”

So: Now they had a prototype that was mostly #2 plastic, with a thin layer of EVOH plastic to lock in freshness.

Greg: It’s mostly HDPE. It’s about 95% high-density polyethylene, which is the target.

Pogue: Okay. And it doesn’t matter for recycling standpoint that there are different kinds of plastic in there?

Greg: Yes. So we engaged with an organization called the Association of Plastics Recyclers, which is a recycling trade group. And early on, we said, “Here’s our idea. We’re developing a tube that will recycle with HDPE bottles. How can we do it in a way that this is valuable material for you?” 

They have a set of criteria that a package needs to meet to be compatible with that stream. And they have acceptable levels of other materials in there, and the EVOH barrier is part of that. And we were able to demonstrate through testing, through data,  that this tube is compatible with the HDPE bottle stream, even going so far as… we took our tubes and made fabric conditioner jugs out of them, and they passed all the performance requirement. 

Pogue: So what happens to that thin layer of plastic that isn’t the HDPE stuff? Does it just get melted down? 

Greg: Yeah. So the small part of EVOH goes with the HDPE and is compatible.

But even with the flavor issue under control, an all-plastic tube would never get off the ground without a fix for the stiffness problem. HDPE is milk-jug plastic. It’s way too stiff! You don’t squeeze your milk out of a milk jug; you pour it. But toothpaste doesn’t pour.

Greg: We’re redesigning it to be high-density polyethylene,  which is a rigid material. And we need to make a soft squeezable tube out of it. So the breakthrough was to use a variety of different layers and grades of high density polyethylene that when used together, gave you the strength you needed with the squeezability in a nice flat sheet. 

It was time to make a prototype. The Prototype 1 tube of 2014. It was squeezable, all right. Unfortunately, the texture came out wrong. 

Greg: So there’s an effect called orange peel, right? So if you think of an orange peel, it’s very stippled on the surface, which is great for a fruit. But for a package you need to print on, makes it much more difficult to produce at scale. So this was, in version one, a big problem we had. So we needed to reformulate the grade of material and the filmmaking process to improve that smoothness. 

Six months later, the team was back with Prototype #2. It was squeezable. It was printable. The only problem…was a side effect that the executives of Colgate-Palmolive, Incorporated could not bear to contemplate: [heavy reverb:] Flavor scalping. 

Loud, dissonant, horror-movie chord.

Meaning, flavor was still leaking out through ​the walls of the tube.

Enter: Dr. Jun Wang, Colgate’s lead materials scientist.

Stephan: You have to meet Dr. Jun Wang. He was absolutely convinced that he would get there. It is a scientist that has such a resilience and passion to solve this problem that for him, there was no question that he was going to get there.

Wang’s solution was to move the EVOH layer inward. The tube walls are made up of very thin layers of plastic, and the EVOH barrier was in the middle of them, like the cheese in a grilled-cheese sandwich. He thought that if they moved the EVOH closer to the toothpaste, it might solve the problem of flavor scalping—

(repeat the horror-movie chord)

—and he was right.

By the end of 2015, Colgate had itself a third prototype. Without any flavor scal— you know. Flavor leakage.

Now, at last, they were done, right? Ready to ship this puppy?

Not quite. The plastic of a toothpaste tube starts out as a big flat sheet. They print on it while it’s still a sheet, which they then chop up and roll up into tubes. The tubes get filled with toothpaste, sealed, and shipped out to your waiting mouth.

But once they’d moved the EVOH layer, the layers of the sheet were no longer symmetrical—the grilled-cheese cheese had moved too close to one side of the sandwich—and the sheets no longer lay flat. Each layer of the plastic reacted differently to tension. And the result was a sheet that wanted to roll up by itself, like a movie poster that’s been rolled up in its tube too long. When they rolled that up into a tube, it wasn’t a perfect cylinder at the opening.

Greg: By moving it inward, you now have an asymmetrical material. 

Pogue: Oh my god. This is way more complicated than you would think.

Greg: And we like round tubes because they look nice, but they’re also important for scale, right? We make very, very high speed, millions of tubes a day. So you need a consistent round tube to work on high-speed equipment.

So—and this is the heart of Dr. Wang’s patent. He engineered a structure where the internal forces in this laminate—and you could think of it, you know, like plywood or like a sandwich of material—he was able to engineer the, the net result of all these materials so that it was dimensionally stable. The forces were counteracting and it was nice and flat, and it made a very nice, round tube. 

In other words, Wang counteracted the unevenness of the different layers’ tensile properties by adding and subtracting various other layers of different thicknesses until the whole thing lay flat. In the end, we’re talking about a lot of layers. A single wall of the finished tube is composed of nine layers of plastic, some of them ridiculously thin—like 15 microns thick. That’s about one-seventh the thickness of a sheet of paper! 

Colgate still had some bugs to work out, but the team had conquered the really showstopping challenges. 

Pogue: I really appreciate what you’ve done here. And I hate to poke holes in it, but guess what? When I throw that thing in the recycling bin, it’s still got caked-on leftover toothpaste, contaminating the plastic.

Stephan: But it’s—I mean, this is very easy, because that toothpaste actually is a water-based product that kind of dissolves in the washing at the recycling facility. There is nothing left. So it’s really not a problem for the recycling facilities.

Pogue: Wow.

Greg: And we also know that people tend to use the vast majority of the toothpaste in the tube. 

Stephan: And they are very creative. People using our product are very creative in getting the last bit of toothpaste out of the toothpaste tube.

And so…after five years and eight generations of prototypes, Colgate finally had itself a toothpaste tube that looked and worked exactly like the ones we’re used to. The only sign that there’s a difference is a little paper flag right at the cap that says “Recycle me!”

They’d solved the materials-science problems. Now they had to face a bigger challenge: the human one. We’ll cover those, after the ad break.

Second Ads

Before the break, Colgate’s director of packaging, Greg Corra, was telling us why it took five years and millions of dollars to re-engineer the toothpaste tube to make it recyclable.

Greg: The version that we brought to market first in 2019 was our eighth iteration of it. And each one—I’ve got a little slide when we share the technology with, with others that shows, one, two, three, four, five and the challenges we had and what we needed to do to overcome that. It was stiffness. It was how well the surface was, how well it protected against flavor. So as with many R&D endeavors, it took iteration. It took creativity. 

Pogue: So was there a big pizza party, beer bash when they finally got it?

Greg: More than one pizza party! But we knew it’s the start of the journey. So internally, we said, “we got step one. We’re now in the second phase of this project, which is external engagement, driving the industry to move to recyclability.” 

What he’s trying to say is that the world wasn’t ready for recyclable tubes. Hadn’t heard of them. Was trained not to expect them. Was inclined to keep tossing them into the trash.

Greg: Most people recycle in the kitchen, not in the bathroom. So we’re hoping that communication on the tube can trigger them to take it from the bathroom and put it in either their bin or wherever they recycle number two bottles.

Pogue: Is there, will there, has there been any advertising around these new tubes?

Greg: [00:57:27] Yes. We’ve done something called Share the Answers in Australia which highlights what to do with the tube. If you look it up, it’s a really cute video of two tubes talking to each other, explaining about the aluminum layer. 

Ad: Knock-knock! Who’s there? Tank. Tank who? Tank you for recycling me!

Pogue: Gotcha. But there hasn’t been a big Super Bowl commercial announcing that you’ve licked this tube problem.

Greg: We did not make a Super Bowl commercial yet.

If you ask me, training billions of people to change their behavior like this is a big challenge. But chief technology officer Stephan Habif points out that Colgate has been in the behavior-modification business for decades.

Stephan: We have quite a bit of experience in our company to positively influence human behavior, to positive outcome. So one of them is brush your teeth twice a day with fluoride toothpaste to get, you know, oral health.  

Jingle: “Brush your teeth with Colgate! Cleans your breath—while it cleans your teeth!”

The other one in the area of sustainability is, turn off the tap while you’re brushing your teeth. You keep improving your communication, your model, until you get to this positive outcome, and in this case is people to recycle the tube, to put it in the recycling bin.

But retraining us, the people, is only half the battle. There are still thousands of workers in recycling plants who have also been trained to throw out toothpaste tubes. 

Greg: As we engaged with these recycling sorters, you know, we were doing a lot of tests. We put radio transmitters on tubes to show it will go into the right place. In one of those cases, we’re filming this tube go into the right place and there’s a human on the end of the line, picked it off, because he’s trained, “tubes don’t go in this line.”

  So even though the automated equipment recognized this tube is of the right material in the right format, the training was there. So a large focus of the work we’re doing now is engaging with recyclers and educating that our tubes are compatible with this stream, and that you can transition from pulling them off to accepting them.

Pogue: So you’ve got to educate those workers.

Greg: Correct. And there are thousands of communities in the U.S. alone that set recycling guidance. So this is not a small scale challenge to work through. But we’re partnering around the world with organizations in this space, with two working groups that include our peers.

Pogue: Two working groups? Are you saying that there — there are tube conferences?

Greg: Oh, my God. Multiple! More than one! So there’s one in North America, there’s one in Europe. We meet multiple times a year. And this is a place somewhere like myself has a very good time.

Frankly, if nothing else comes of having written this podcast episode, just knowing that there is such a thing as tube conferences will have made it all worthwhile.

I think what Colgate has done is remarkable. It’s obviously not something they did for PR value—I mean, until “Unsung Science” came along, as far as I know, hardly anyone even knows they did it. It’s something they did for the good of the planet, even though it costs them time and effort to bring about.

But here’s the thing. Colgate may be responsible for half of the 20 billion tubes we throw away each year—but what about Crest, and Aquafresh, and Arm and Hammer, and Sensodyne? 

If they don’t also switch to recyclable tubes, then we’re in a really awkward position. Not only are 10 billion tubes a year still going into the landfill and the ocean, but Colgate’s own 10 billion will probably get tossed, too—because we can’t really expect recycling plant workers to study every tube that comes down the line and figure out, one tube at a time, if it’s the recyclable kind or not.

No—if this is going to work, they all have to be recyclable.

And that’s where this story takes a twist.

Greg: A year and a half away from launch, I walked into a meeting and it was, it’s called the North America Tube Council, which is tube manufacturers.

I love that there is a North American Tube Council. I would very much like to have a North American Tube Council T-shirt. Anyway…

Greg: I did a presentation that outlined our plan, the target for an HDPE tube. I told them, “you’re all invited to join us in this. We will not defend our patent. We’re going to open it up.” That audience took note and said, OK, “Colgate’s going down that way, you know,” and it happened the way we thought, that we’d signal how important it was for us.

Stephan: We made this patent available to anyone in the industry who wants to use it. We wanted to make sure that ideally, if all the toothpaste tubes were recyclable, there would be much less barrier for the recycling community to accept these tubes because they don’t even have to do any sorting. 

Pogue: You develop this thing and now you’re giving it away. I mean, that’s, that’s a pretty good gesture. 

Greg: It became clear that we had to drive an industry change, and that squirreling this away would be counterproductive to driving that change.

In case you’re wondering: The other American toothpaste giant, Crest, was not among the companies who availed themselves of Colgate’s technology. They did, however, develop their own version of these tubes. Crest, too, is now making its tubes out of multi-layer #2 HDPE plastic. And Crest, too, has launched a huge education campaign for consumers and recycling plants.

All told, nine years after Colgate started down its recyclable-tube quest, we can report this astonishing statistic:

Stephan: 90% of the major manufacturers of toothpaste have agreed to switch to recyclable toothpaste tubes, and therefore will be able to switch the whole industry. And it will be so much easier, because in the future when we get there, there won’t be any question, is it recyclable or not? 

Pogue: I mean, that is like the first decent, positive, undisputable, good piece of news in the plastic pollution world I’ve heard in a long time. I mean, presumably ten years from now, you won’t see toothpaste tubes in the landfill.

Greg: That is our hope and that’s our goal.

I love this story. I love that an industry decided to clean itself up. I love that somebody is doing something about the plastics problem. And by the way, this episode is decidedly NOT sponsored by big toothpaste. No money changed hands. Colgate didn’t even approach me about doing this podcast—I approached them.

But I had one last niggling doubt. Niggling, but enormous. I’d been deeply affected by a really discouraging report on the Greenpeace website. It argued that the entire concept of plastic recycling is a myth. Here, I’ll read it to you: 

“The plastics and products industries have been promoting plastic recycling as the solution to plastic waste since the early 1990s. Some 30 years later, the vast majority of U.S. plastic waste is still not recyclable. The U.S. plastic recycling rate was estimated to have declined to about 5–6% in 2021, down from a high of 9.5% in 2014.

Recycling of plastic waste has largely failed and will always fail, because plastic waste is: (1) extremely difficult to collect, (2) virtually impossible to sort for recycling, (3) environmentally harmful to reprocess, (4) often made of and contaminated by toxic materials, and (5) not economical to recycle. 

Paper, cardboard, metal, and glass do not have these problems, which is why they are recycled at much higher rates.” End quote.

I asked Greg Corra about that.

Pogue: We recycle so little of our plastic, I mean, somewhere between 5 and 8% is all we manage. So do you ever wake up in the middle of the night going, “What are we doing? We can’t even get people to recycle at all?”

Greg: The stat you mentioned is considering all plastics, including lawn chairs and other things. When you get down to specific materials and formats, that number still is not as high as it needs to be, but it’s much higher. It’s in the thirties, it’s in the forties, depending on country. And that’s why we chose HDPE.  

Is it where it needs to be? Not at all, right?  So that’s why we engage with the recycling partnership in the U.S., the U.S. Plastics Pact, plastics pacts around the world, because that number needs to go up.

And, to be perfectly fair to Colgate and Crest, the Greenpeace article goes on to say that #1 and #2 plastic recycling is not a myth. That they are quote “widely accepted” by US recycling plants.

I mean, someday, scientists hope that we won’t need any kind of plastic for packaging—or at least any kind of petroleum-derived plastic. There are all kinds of materials that come close.

I’ve been the host of 20 specials on “NOVA,” the PBS science series. And one time, I visited Boston University chemist Malika Jeffries-El. 

She showed me a cup made entirely of plant-based plastic. It was clear, it was sturdy, it was compostable and recyclable—it looked for all the world like any other plastic cup. So why isn’t the world using that plant plastic instead of oil plastic?

Malika:          The biggest limitation / is their range for thermal stability. 

David:            Their range for thermal stability. 

Malika:          Yeah. So in layperson’s terms, you cannot use this for a hot drink.  

David:            Oh. 

Malika:           Perfectly good for your cool beer. Your soda on the rocks. It’s got you covered. But you want to make a hot tea in there, you’re going to be in trouble. 

David:            Well, what what would happen? 

Malika:          Well, we could put boiling water in here, and let’s see what happens. Right. 

David:            Oh, cool! Oh, did you see that? It kind of shrunk up. Oh, it just turned into a compact travel size.

Malika:          It’s definitely got its niche. But you know, you’ll be surprised on the dumb things that people people do. 

The point was, it’s very hard to find a material that does everything plastic can do, as well as plastic can do it.

OK, back to Colgate:

Pogue: So is there no other material in the world, anything more biodegradable that could be used for these tubes besides plastic? 

Greg: We absolutely looked at a range of materials, and we continue to look at range of materials. I would not say it’s hopeless. We are focused on a number of avenues, which includes compostable packaging. I wouldn’t say it’s right around the corner, but it is something. 

So until we find that miracle material, recyclable plastic it is. 

As we speak, three-quarters of Colgate’s tubes in the U.S. are recyclable; the company intends to complete the transition to 100%, worldwide, by 2025. Which is, as we now know, an achievement in itself.

Pogue: You know, after this episode, people are going to hold that stupid toothpaste tube like it’s a treasure from the deep. Like, so much work went into this!!

Greg: This is my life. (laughter)



You’ve just listened to another episode of “Unsung Science” with David Pogue. Don’t forget that the entire library of shows, along with written transcripts, await at 

My guests today were Stephan Habif and Greg Corra from Colgate, Roland Geyer from UC Santa Barbara, and Malika Jeffries-El from Boston University, whom I thank profusely. I’m also grateful to WGBH for permission to use the clip from one of my “NOVA” interviews.

This podcast is a joint venture of Simon & Schuster and CBS News, and it’s produced by PRX Productions.  

For Simon & Schuster, the Executive Producers are Richard Rhorer and Chris Lynch.  

The PRX production team is Jocelyn Gonzales, Morgan Flannery, Pedro Rafael Rosado and Morgan Church.

Jesi Nelson composed the Unsung Science theme music, our fact checker is Kristina Rebelo, and Olivia Noble fixed the transcripts.

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