Are microplastics really a problem?

Our listener Louisa is very annoyed by her sister’s preoccupation with keeping her children away from microplastics. Louisa wonders: are people with microplastics anxiety kind of overdoing it? Search Engine investigates. Support Search Engine! https://searchengine.supercast.com/

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00PJ Vogt?

  Hello, search engine listeners. We are back with a new season, season three. We have new questions and new answers for you. Our team is recharged. We are so happy to be back in the studio. As always, if you would like to support our quixotic venture here, the best way to do it is to sign up for a premium membership at searchengine.show. We call it incognito mode. And next week, we will have a special treat for our incognito mode listeners. Next Wednesday, for our premium subscribers, we're sharing my conversation this summer with podcasting superstar and infamous diva Jonathan Goldstein of Heavyweight. He dished on his rise to podcast celebrity, his many famous feuds and squabbles, all the romances and how he almost threw it all away.

• 0:44PJ Vogt?

  Just kidding. We had a fun conversation about podcasting and celebrated the return of Heavyweight. But if you want to hear that conversation, you need to sign up for incognito mode, our premium feed at searchengine.show before next Wednesday. Okay, enough talking about podcasts about podcasting. Let's play our podcast after these ads.

• 1:05PJ Vogt?

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• 1:51PJ Vogt?

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• 2:09PJ Vogt?

  This episode of Search Engine is brought to you in part by Mint Mobile. Remember back when you were a kid and you'd spot something cool at the store, only for your mom to remind you to just wait until the holidays? Well, Mint Mobile is giving you the present early with zero waiting required. Right this minute, all of their wireless plans are available for just $15 a month. If you make the switch to Mint, your monthly expenses will take a huge dip without your signal quality taking a hit. You get high-speed data, unlimited talk, and unlimited text powered by the nation's largest 5G network. There's no need to buy a new device either. You bring your own phone and keep your current number. So what are you waiting for? To get your new wireless plan for $15 a month, go to mintmobile.com search. That's mintmobile.com search. Cut your wireless bill to $15 a month at mintmobile.com search.

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• 3:40PJ Vogt?

  Sometimes I wonder, if I'd lived in the past, would I have made the right decisions? Even if almost everyone else was making the wrong ones? I don't mean the big moral questions. I'm not talking about Germany in the 1930s. I actually just mean health questions.

• 3:58PJ Vogt?

  Like, it's the 1800s. You live in America, and you're trying to decide what you can safely do to your own body. And here and there, you can find these articles suggesting that a few things a lot of people routinely do are actually very dangerous. Like, you can open up a newspaper and read an article claiming you ought to worry about a condition called bicycle face. This is that condition where the physical strain of riding a bike changes the shape of your face permanently into a kind of wretched grimace. Bike riding, you might read, can also damage women's fertility. Okay. Honestly, knowing me, a person who likes new technology

• 4:41PJ Vogt?

  and tends to ignore scientific warnings until they reach a pretty high consensus, a jeweled for a spell, I think in the 1800s, I'd probably ride bikes. I'd ride bikes, but I'd avoid the wolf peach. In the early 1800s, wolf peaches were an exotic fruit that some people enjoyed, but which many people warned could be fatally poisonous. I like risk, but I'm also kind of a picky eater, so I would not have experienced the pleasure of a good summer wolf peach, a fruit which today we just call a tomato. I would have succumbed, I guess, to the tomato moral panic. So I'm one for two. Another 1800s health decision I would have had to make: cigarettes. Cigarettes had just gone from being hand-rolled,

• 5:25PJ Vogt?

  and so a rare, expensive luxury, to very, very cheap. The automatic cigarette roller takes off in the 1880s, plunging the price to pennies per pack. There were health warnings at the fringes. A German medical student named Herman Rotman was arguing that lung tumor rates seemed to shoot up in populations after cheap cigarettes arrived. But if I'm honest, I'm almost certain I would have been a very heavy smoker. It was social. It was fun. The science was nowhere near settled. In the 1800s, I ride my bike. I carefully avoid tomatoes. And I wheeze and cough a lot before dying for reasons I don't understand.

• 6:06PJ Vogt?

  But what about our present day and its new wonders and dangers? A lot of the questions we get at Search Engine come from listeners who want to know if something new is safe or not, or how much they need to worry about it. And the question that sits at the top of the should I be worried about this pile is a question we've been getting some version of for the past two years, recently from this listener. Um, I think the first thing I should just say is hello.

• 6:33Speaker 01

  Hello. Nice to meet you.

• 6:36PJ Vogt?

  Nice to meet you. First things first, this is the same question we ask everybody. It's a very easy one. What's your name?

• 6:42Speaker 01

  My name is Louisa.

• 6:44PJ Vogt?

  You emailed with a question you had where the question came out of your relationship with someone you identified as a relative. I don't know, maybe you want to keep that level of anonymity, but can you tell me about the relative?

• 6:55Speaker 01

  It's a very close relative. It's, it's my sister. It's my sister. I'm not that judgmental with that many people. Like, I'm just a family know-it-all. So the question came out of my relationship with my sister. So we're a very close family, a nuclear family. I have an older sister and a younger brother. My brother passed away about two years ago.

• 7:18PJ Vogt?

  I'm so sorry.

• 7:19Speaker 01

  So, no, thank you. Actually, your episode on fentanyl was like one of the first things I'd listened to. He passed away from fentanyl and my dad and I listened to it together. It's just like we're looking for solutions thing because that's just how the family we are. Anyways.

• 7:35PJ Vogt?

  Yeah.

• 7:36Speaker 01

  It was like really intense to like lose a family member and then like my sister like got pregnant with twins. And so I think everybody is on like, we're all just also a little bit amped up. Like, we're a bunch of neurotic Jews in a way, and you know what I'm saying?

• 7:50PJ Vogt?

  Yeah, there are a lot of things. There's like grief, there's new life, there's parenthood, there's uncertainty, like everyone's kind of...

• 7:58Speaker 01

  Opinions, like constant level of anxiety. That's the scoop.

• 8:02PJ Vogt?

  In Louisa's email to search engine, she'd explained how in this amped up, high anxiety family system, she'd found herself being driven somewhat mad by this one thing that her sister was doing around the kids. Hence her question.

• 8:15Speaker 01

  I'm actually kind of embarrassed of my question because I know exactly when I wrote it. I wrote it on an angry dog walk. And that's why there's like typos and I'm writing "you are" instead of "you're" or whatever. Anyways.

• 8:26PJ Vogt?

  Well, was it what prompted the angry dog walk?

• 8:28Speaker 01

  So I was probably angry because I had either just spoken with her or spent some time with her. We were probably at her apartment hanging out with the babies. And they have this thing of like filtered tap water, I guess, sitting on the counter next to the sink. And like, we're in Vancouver, British Columbia. We have great tap water. And she was like, oh, no, no. Like, don't wipe their face with that water. And I was just like, what? And she's like, just there's microplastics.

• 8:56Speaker 01

  And I was like, what do you mean? And she just starts going on about how like the clothes she gets, everything she brings in for them and this and that. She wants to prevent as many microplastics from being breathed into their lungs as possible. And that's when I was like, Houston, we have a problem here.

• 9:12PJ Vogt?

  Microplastics. Infinitesimally tiny flakes and flecks of plastic that in recent years we've learned slough off of plastic material and sometimes find their way into our bodies. One of those facts about modern life I wish I could unlearn and which actually I'm usually very good at intentionally forgetting.

• 9:33PJ Vogt?

  Not so for Louisa's sister. According to Louisa, it is the headline in her sister's brain much of the time.

• 9:41PJ Vogt?

  Can you just draw me a picture? She's afraid of microplastics. She's worrying about microplastics as like an unusually perhaps high priority. And if I were to just walk into the house, what would I see that would tell me that?

• 9:53Speaker 01

  They don't have a lot of toys. All the condiments and things are in glass. The water thing on the counter, I guess, is glass. Apparently, all their clothing, like we talked a lot about baby clothes, they have to be this like organic bamboo cotton. So there's like a hyper-focus of both her and her husband on microplastics all the time. And I can see like signals between them like, nope, not that, da, da, da, da. But I'm like, guys, the kids are in this world. They're in this world now. And there's dangers everywhere. I'm worried about my sister because I'm always worried about my siblings. And I'm worried that her worry is just going to affect her too deeply and disable her

• 10:38Speaker 01

  to take care of these kids. Does that make sense? It's like, I need her to worry less. So my question is, are microplastics really a problem? Should we be worried about our babies and microplastics and all of the things that are to be worried about bringing babies into this world? Is that the one to hyper-focus on?

• 11:05PJ Vogt?

  So that is Louise's question, which is really two questions, right? Pretty different ones. One is just microplastics. How much of a problem are they really? But question two is really a question about parenting. To be a parent is to purchase a lifetime subscription to worry. The risks we'd happily take for ourselves are just not the same as the risks we accept for our children. But even the most accomplished Olympic-level warriors have to decide how to order their worries, or outsource that decision to podcasters. After the break, we are going to take on the first of these two questions. What do scientists actually know right now about microplastics? That's after these microscopic advertisements.

• 12:06PJ Vogt?

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• 13:04PJ Vogt?

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• 13:49PJ Vogt?

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• 14:07PJ Vogt?

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• 15:22PJ Vogt?

  Welcome back to the show. So, plastic. Plastic may not feel to you, it didn't feel to me, particularly new, not as novel and mysterious as a fresh wolf peach. But reading about plastics history, I was struck by how actually that's not right. In the sweep of things, plastic is new. And because it's so useful, light, flexible, sturdy, it's become ubiquitous without becoming comprehensible to us, the way wood or metal is. The story of plastic starts only about 150 years ago.

• 16:00Speaker 02

  The old adage has it that necessity is the mother of invention. Nowhere is this truer than in the field of plastics.

• 16:08PJ Vogt?

  This is a wartime educational reel, celebrating plastic. The narrator tells the origin story of this strange man-made material. He explains how in 1869, human beings were trying to solve a very specific problem: ivory shortages.

• 16:23Speaker 02

  Ivory, a natural product of elephant tusks, was used at that time to make billiard balls.

• 16:31Speaker 02

  And piano keys.

• 16:33PJ Vogt?

  Ivory was used back then for a lot, actually. In combs and toothbrush handles, chess pieces and dominoes. And importantly for our story, billiard balls back then were often made out of ivory. And there was a billiards craze in the 1860s. And so humans were mass slaughtering elephants, in part so that other human beings could experience the profound thrill of sinking the ball in a corner pocket. We're an unusual species. But billiards fans ran into a problem, which was that the high demand for ivory meant too many elephants were being slaughtered, and the price for their tusks was skyrocketing.

• 17:07Speaker 02

  But it was going too costly. The growing demand, the slaughter of whole herds of elephants in the long haul from the Congo to the States, all these made it necessary to find an available substitute. Now was the time to come to the aid of the grand old pachyderm.

• 17:21PJ Vogt?

  And so a New York billiard ball company announced a contest. A $10,000 prize to the genius who could invent or discover some alternative material for the world's billiard balls. We had to save billiards. A man named John Wesley Hyatt decides it's gonna be him. A garage inventor, Hyatt starts experimenting with different chemical combinations at home.

• 17:43Speaker 02

  By treating cotton ladders with nitric acid, just as this chemist is doing, and then adding camphor, John Wesley Hyatt found that the resulting mixture, a gooey semiliquid substance called a resin, could be molded into permanent shape by heat and pressure. Hyatt called the new substance celluloid.

• 18:03PJ Vogt?

  Celluloid, the first popular plastic, proved to be an extremely useful new material. Easy to shape, yet sturdy, water resistant, it didn't really seem to degrade over time. You could even make it in different colors. Celluloid helps open the door to a new American pastime, mass production. We begin to manufacture lots of goods, goods that are pretty cheap to produce. We love this new material. The miracle of plastic seems to be that while wood rots and metal corrodes, plastic, apparently, lasts forever.

• 18:37PJ Vogt?

  One obvious catch with celluloid is that it is unfortunately quite flammable. Two celluloid pool balls knocked together hard enough could actually explode. So while celluloid is useful, there's still demand for some kind of non-flammable plastic. We invented it about 40 years later.

• 18:55Speaker 02

  It was not until 1907, another Roosevelt was then in the White House, that a non-inflammable plastic was invented by Dr. Leo Bakelite, to which he gave the name Bakelite.

• 19:06PJ Vogt?

  Bakelite, even better than celluloid, cheaper, more durable, and now it doesn't catch fire. And so we're off to the races. In the decades that follow, we keep finding new chemicals to make plastics out of. These days, it's mostly petrochemicals, and our love for this material will only deepen. During World War II, we use it for the liners of our troops' helmets, for their goggles. We produce nylon for their parachutes, plexiglass for their warplanes. And after the war, we take our newfound muscular plastic generating capacity and flood the consumer market with cheaper goods. This is a story mostly about plastics' downsides, but I do want to briefly remind you that

• 19:49PJ Vogt?

  plastic has arguably given us more than it's taken. Plastic has not just helped us consume more cheaply, something we might feel ambivalent about. Plastic has saved millions of lives. You see a lot of plastic in hospitals. Plastic fringes, plastic IV tubes, plastic stents. The seatbelts in our cars contain plastic. You need synthetic fibers since cotton degrades. Our airbags contain plastic. When it is not terrifying us, plastic can be a miracle. And for most of its time here, that was the only way we really viewed it.

• 20:21Speaker 02

  Modern-day miracles that were made with the help of petrochemicals.

• 20:28Speaker 03

  Step into the world of man-made materials that take up where nature left off. This is an American city, a real community of homes and homemakers like thousands of others across the nation. We call it Plastics Town, USA.

• 20:43PJ Vogt?

  We eventually noticed that this particular miracle has an asterisk after it in the 1960s, when the environmental movement takes flight and plastic litter becomes a concern. In the 70s, marine biologists begin to document the plastic debris floating in our oceans. We realize that there is an issue now.

• 21:03PJ Vogt?

  The problem with plastic is that while wood rots and metal corrodes, plastic, apparently, lasts forever.

• 21:11PJ Vogt?

  In 2004, marine biologist Richard Thompson coins the phrase "microplastics" to describe the very small, sometimes microscopic, plastic fragments he and his colleagues are detecting in the oceans. Before we even knew to worry that this stuff might be in our bodies, it was the plastic in the oceans and in the bodies of fish and other sea life. There was a sign for people that something may have gone more wrong here than we'd realized.

• 21:34Speaker 04

  Do you remember the famous turtle with the straw up its nose?

• 21:37PJ Vogt?

  This is Professor Tracy Woodruff. She teaches at the University of California, San Francisco. She runs the program there on reproductive health and the environment. I don't remember the famous turtle with the straw up its nose. What was the famous turtle with the straw up its nose?

• 21:49Speaker 04

  There's a video that went viral about a turtle that got hurt by a straw. And this led to a lot of governments, like, for example, in San Francisco, they banned plastic straws because it's symbolic that plastics are getting out and about into the environment and they're harming aquatic life.

• 22:08Speaker 05

  Bless you.

• 22:10Speaker 06

  Have you ever heard a turtle sneeze?

• 22:12Speaker 05

  I have.

• 22:13PJ Vogt?

  I went back and watched this video after my conversation with Tracy. It is very, very disturbing to watch.

• 22:19Speaker 07

  You know what this is?

• 22:20Speaker 06

  What is it?

• 22:21Speaker 07

  Green. That's a worm.

• 22:23Speaker 06

  Oh, that is disgusting.

• 22:25PJ Vogt?

  Marine biologists are restraining a large turtle. They're using pliers to try to remove an as-yet-unidentifiable white thing that's lodged in his nostril.

• 22:33Speaker 07

  I don't know how deep and I don't want to pull it.

• 22:35PJ Vogt?

  As they pull it out, the turtle's nose begins to bleed. He starts to sneeze and to writhe. They finally remove the object, at which point they realize what it is.

• 22:47Speaker 06

  It's a freaking straw. Don't fucking tell me it's a freaking straw.

• 22:51PJ Vogt?

  A plastic straw. The notion that pieces of plastic were increasingly ending up in the bodies of sea creatures, that actually opened the door for Professor Tracy Woodruff to ask whether plastic may also be ending up in human bodies.

• 23:04Speaker 04

  I think it was like, oh, plastics in the ocean, that makes sense. And then, oh, plastics in animals. Okay. Well, if there's plastics in the ocean, and then there's plastics in the environment, and then there's plastics in animals, and we're an animal, it makes sense that there's plastics in us. And then from there, it all, it all kind of came together and clicked.

• 23:23Speaker 08

  Plastic sometimes gets broken down in what are called microplastics, which is a problem we're only just beginning to understand.

• 23:31PJ Vogt?

  Scientists actually started finding microplastics in our bodies very recently. The first study arrived in 2018.

• 23:36Speaker 09

  Microplastics spread through the water, air, and even human bloodstream. They've been found.

• 23:41Speaker 10

  Plastics found in kidney tissue, liver tissue, placental tissue. There was an article in the spring.

• 23:47PJ Vogt?

  We're still trying to figure out what to make of all this. Besides, of course, lots of worrisome TV news segments. Which is why I was talking to Professor Tracy Woodruff. So just on a super basic level, how exactly do microplastics get into the human body? What is happening?

• 24:04Speaker 04

  Yeah, so microplastics, they're less than five millimeters and way smaller. So it's like the size of a pencil tip all, but they can be much smaller in range, all the way down to smaller than a virus, smaller than a red blood vessel. So you have a large range of these very small plastic particles. Some of them are intentionally manufactured, right? So they're used in things like cosmetics, paint, laundry detergent. But the majority of them break down from single-use plastic. So, single-use plastics include things like your plastic water bottle. But there's also other contributors, like car tire wear can

• 24:44Speaker 04

  also contribute. Clothing is an important source of microplastic exposure because clothing is made from like rayon or polyester can degrade.

• 24:52PJ Vogt?

  Wait, but I never wear plastic clothes, I don't think. You're saying microplastics are in some fabrics?

• 24:58Speaker 04

  Yeah, like rayon, polyester. Do you wear fleece?

• 25:02PJ Vogt?

  I've been known to wear a fleece.

• 25:03Speaker 11

  Me too. Oh, my God. Someone... The thing that's been so interesting about doing this is like, I myself am like, what? There's plastic in what? Anyway.

• 25:13PJ Vogt?

  Plastic is everywhere. Microplastics are too. They get into our bodies typically through ingestion or inhalation. And even if you manage to keep a plastic-free home, microplastics have their ways.

• 25:28PJ Vogt?

  You can inhale microplastics from the air, for instance, via the microplastics that had rubbed off of car tires and become tiny airborne dust. The tap water you drink can contain microplastics. They flake off people's clothes in the washing machine. They survive the trip through the water treatment plant back to your drinking supply. Learning all this, I found myself much more nervous about microplastics than I had been in the weeks before.

• 25:55Speaker 11

  It's gross. This definitely is not good. And this is something where it's just, nobody is arguing this is good.

• 26:02PJ Vogt?

  This is Professor Emily Oster. She's an economist. A lot of her research is on health and development. She's made a career helping people decide what the evidence is actually showing us when it comes to questions about our own health and often the health of our children.

• 26:16Speaker 11

  Nobody's like, great idea, consume a lot of tiny pieces of plastic to become like a bionic plastic human, right? Nobody thinks that. And so it's sort of our upper bound on the possible thing is maybe it doesn't matter. That's like the best-case scenario is it's just a gross weird thing that doesn't matter. And then the worst-case scenario is it is in some way damaging.

• 26:39PJ Vogt?

  Emily and Tracy are going to be our guides through the science here. There have been a number of studies around microplastics. We at Search Engine have now spent a good amount of time in them. Frankly, the science does not yet seem entirely settled. A fair amount is uncertain. And so these two experts are going to help us walk through all this. They've both spent time thinking about microplastics and have ended up with slightly different conclusions, which we'll get to. But for now, what we know is that microplastics are inside of us, and we know that that is not optimal. But what is actually happening to our bodies once they become hosts to microplastic collections? Professor Tracy Woodruff leads and collaborates on a research team that studies

• 27:22PJ Vogt?

  exposures to chemicals in plastics and how they influence our health, particularly when it comes to pregnancy. She talked to me about how this research even works, given you can't ethically just expose one group of people to lots of microplastics on purpose in order to study them.

• 27:39Speaker 04

  When we're talking about looking at chemical exposures, for example, typical ways that we do this in environmental health is we use animal studies, so rats and mice, where you can control their exposures and you could have a control. Basically, what we see in animals reflects what we would see in humans.

• 27:57PJ Vogt?

  And with the animal studies, were the animals being exposed to the chemicals in microplastics or microplastics themselves? Like, is it like you're giving a mouse water and you're putting tiny little particles of plastic spoon in it?

• 28:12Speaker 04

  So they basically purchase small microbeads. And plastics is made of different types of materials. Some of them are polystyrene, some of them are polyvinyl chloride. So they purchase these beads, and they're microbeads, and then they put it in the water, or they put it in the food, and the animals eat it.

• 28:32PJ Vogt?

  So these animals are dosed with water and food that has lots and lots of plastic microbeads inside. What happens to their bodies? Nothing you'd want to happen to your body. Mice pumped full of microplastics, for instance. Males have their fertility rates drop, the females miscarry more often. Their offspring, if they have them, can have metabolic disorders. And this is not just one study or one kind of animal. Feed a honeybee microplastics, it'll lose some of its memory. In fish, microplastics can cause tissue damage. In birds, a new disease called plasticosis, where the birds suffer fibrotic scarring to their digestive tracts.

• 29:14PJ Vogt?

  Again, these are mostly animals in lapse, not humans in the world. But it's concerning. Tracy Woodruff explained her hypothesis for how microplastics could be affecting human bodies, once they get inside of us.

• 29:26Speaker 04

  Inflammation, they can cause your cells to react to the microplastic and attack it as a foreign body, or they can increase immunosuppression because it's not just microplastics we're exposed to. We're also exposed to perfluorinated chemicals, which we know can increase health effects. We're exposed to these thallate chemicals. We're exposed to BPA. We're exposed to flame-return chemicals. So we think some of the chemicals could come off of the microplastics, and then those can perturb different type of biological systems.

• 29:59PJ Vogt?

  What Professor Tracy Woodruff is saying here is a little complicated. She's saying that we're both trying to study how microplastic particles alone could hurt us, these tiny little fragments in our bodies wandering around, damaging our tissue, but also how the toxic chemicals inside of those fragments can hurt us, once they leach out. And this is the part of the story that I most experience as the feeling of a dark forest filled with question marks. What we know is that there are chemicals in plastics that are endocrine disruptors, meaning they confuse our body's hormonal systems, which in some cases could affect people's reproductive health. We know that.

• 30:40PJ Vogt?

  And then there's been a lot of strange things happening to our bodies over the past few decades that we cannot definitively explain. Men, on average, have lower testosterone levels than they did a few decades ago. There are more adult women struggling to conceive. There are more girls entering puberty earlier. We don't know how connected these things are to environmental toxins, but a lot of scientists are looking at this, including Professor Woodruff.

• 31:08PJ Vogt?

  And scientists have noticed that sometimes, not always, but sometimes, when we compare one group of people having these health issues with a group that isn't, we'll find that the group that's struggling has more microplastics in their bodies. From Professor Tracy Woodruff's perspective, we've made a big change to our environment. We're seeing changes to our health. We know that microplastics make animals really sick. And so there's a real possibility that we're all poisoning ourselves in a way that 100 years from now will seem like a real calamity. That is the scary version of the story. But I should say that that version of the story is a hypothesis. It includes some educated guesses. And it is possible for a reasonable person to look at the same studies

• 31:53PJ Vogt?

  and come to a somewhat different conclusion. Professor Emily Oster, a reasonable person, an economist who is very skilled at studying health data and assessing risk, she says, wait a minute. Let's look at all this from another perspective. She starts with the same animal studies, and at first, she sees the same things.

• 32:13Speaker 11

  So if you expose mice, which is our most standard animal model, to like very high doses of microplastics, it causes a bunch of different negative consequences in different body systems, digestion, respiratory system, the fertility system, the endocrine system.

• 32:30PJ Vogt?

  But when it comes to extrapolating this to humans, Emily Oster has a good question. Do we believe that human beings are being exposed to microplastics at doses that would actually affect our health?

• 32:43Speaker 11

  That is a question, and that is where the evidence, I think, is not especially compelling. So the doses that humans are exposed to, even though there's a bunch of it in your brain, they are way, way lower than the doses that we're exposing animals to in these studies. And there is a fair amount of disagreement about whether those doses are in fact bad enough to have any measurable negative impacts on people. We don't have a lot of direct evidence, or really any direct evidence, that would say having a lot of microplastics makes you less healthy. So I think there's actually a legitimate disagreement about whether, at the levels people are exposed to, this is actually a health problem that would be important,

• 33:28Speaker 11

  like you would want to be concerned about it for yourself.

• 33:31PJ Vogt?

  When you say that, like, level disagreement, you mean like, it's not that there's strong, clear evidence that this is definitely okay, it's just there hasn't been strong, clear evidence that it's having an effect?

• 33:42Speaker 11

  Yes, that's what I mean. And I would also add to that, that if the effects were very large, I think we would see them. So we're sort of in a space where I would say the disagreement is, at this level of exposure, would there be any measurable negative effect or not? I think if the effects were enormously big at these low levels, those we would have already seen.

• 34:11PJ Vogt?

  Emily Oster's point, and this is where she and Tracy Woodruff really do depart from each other. Emily Oster believes that if microplastics, at their current levels, directly caused serious health problems in humans, that would be obvious in the data. We wouldn't be wondering about it. We'd know it. And that's not what she sees. Tracy Woodruff, she's much more concerned with where we are right now with microplastics, generally with toxic chemicals in our environment. And she has questions about illnesses whose rates have increased. For instance, she suspects a possible link between rising colon cancer rates and microplastic exposure. Emily Oster says the scientists she's spoken to see alternate explanations for that rise.

• 34:55PJ Vogt?

  For instance, it could be our rising rates of obesity. But it's interesting how much we don't know. It could be obesity, it could be microplastics, it could even be the two together. Microplastics could disrupt our digestive systems, which could contribute, owing with diet and lifestyle, to obesity, all of which might spike colon cancer rates.

• 35:17PJ Vogt?

  One day, we will probably know with more certainty. Today, we're still trying to reach a consensus about how dangerous microplastics are to human beings in the present moment. Oddly, our conversation about the future is actually a lot more harmonized. Since we know that microplastics can reach toxic levels in our bodies, and that more plastic means more microplastics, we also know that we want to try to find ways to avoid increasing our global plastic consumption. Professor Tracy Woodruff told me, though, that is unfortunately not how things seem to be shaking out.

• 35:54Speaker 04

  Right now, the projection is for plastic production to triple by 2060. So think about it now, we know something about plastic and its impacts on our health. If we wait another 30 years to address this problem, we'll just have even more plastic and it'll just be even harder to address.

• 36:11PJ Vogt?

  Wait, we're planning to triple our plastic production in the next 35 years?

• 36:16Speaker 04

  That's what the estimates are, yes.

• 36:18PJ Vogt?

  And where is that coming from? Why are we making so much more plastic? Everybody gets three water bottles?

• 36:27Speaker 04

  How many do you have?

• 36:28PJ Vogt?

  A lot, and they're all plastic, frankly. I like the analogy, even if it might be, you know, nuking my testosterone.

• 36:37Speaker 04

  So, okay, here's the thing. This is the relationship between climate change, fossil fuels, and plastic. So the fossil fuel industry has had a couple factors influence the production of fossil fuels. And now, of course, things are a little bit in flux now with the new administration. But there had been a lot of regulatory policy, government focus on transitioning to electricity away from fossil fuel gas coming from the ground, away from coal, in order to address climate change. Well, once you do that, right, more electric cars, more electrification of houses, well, you're a fossil fuel company and you've got all this fracking product coming out of the

• 37:19Speaker 04

  ground, you're not going to be like, oh, I guess I'm going to hang it up and go home. You're like, well, how, what are we going to do with all this product we have? Well, we're going to turn it into plastic. That's our new product line, is plastic.

• 37:33PJ Vogt?

  It's a funny paradox. The thing most of us agree is good, less reliance on fossil fuels, could create a strong incentive for something most of us would agree is bad. Way more plastic in our environment, creating much higher levels of microplastics in our lungs, our hearts, the tissues throughout our bodies. We live in a very complicated world.

• 38:04PJ Vogt?

  After a short break, we return to the question that brought us here. I ask what now feels like a relatively small question. How do these two experts think that Louisa, our listener, should think about her sister's anxiety around her baby's exposure to microplastics? It's after these ads.

• 39:32PJ Vogt?

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• 40:15PJ Vogt?

  If these public servants can't survive in government today, what does that say about us? I am so excited that this new book is out. Michael Lewis is one of my favorite authors. I read everything he writes, and I'm very excited for this one. Blockers by Michael Lewis, available wherever books are sold. Learn more at blockersbook.com. This episode of Search Engine is brought to you in part by Viori. I have been living in my new gear from Viori, and honestly, it has completely transformed my daily routine. I picked up the Sunday Performance Jogger from their Sunday collection, and they've quickly become my absolute go-to pants, whether I'm heading out for an early morning run, working from home, or grabbing coffee with friends.

• 40:57PJ Vogt?

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• 41:44PJ Vogt?

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• 42:59PJ Vogt?

  Welcome back to the show. If it's okay with you, I'd like to take a moment to just talk about worry.

• 43:06PJ Vogt?

  As a human being, I worry more than most people I know. It's the first thing close friends notice about me when I get comfortable enough to show them the realer version of myself. I have a very 4K imagination for stories about how things in my life might suddenly go wrong. I experience my own worry often more vividly than I experience actual reality. Obviously, there's a lot of downsides to that, but an upside is that I connect very easily with other worriers. And I can actually be pretty calming for them, since the nightmares playing in their heads are different from whatever screening in my personal hell matinee. Which is probably why Louise's email jumped out at me. A person writing to describe how overwhelmed she was with worry, so overwhelmed it made her mad.

• 43:51PJ Vogt?

  Her worry about her sister's worries, about her sister's twins. I identified with everyone. The new parents most of all. Parenting is such an amplifier for worry. Newborn twins, I can't even imagine.

• 44:05PJ Vogt?

  Before I spoke to Emily Oster, who you heard from in the last part of the story, I spent a lot of time reading her work. I read it because of my own worries and my project of trying to learn to live less fitfully within them. Emily is famous on some parts of the internet for this book series and website she's built called Parent Data. It's a project with a neutral sounding name, but a very ambitious mission. Emily is very good at sifting through evidence. And she'd noticed that there was a lot of media, blog posts, articles, podcasts, designed to spike parental worry, but very few public thinkers carefully just looking at the evidence, deciding which of the possible dangers to our children might be somewhat overrated or underrated. Just what did the

• 44:48PJ Vogt?

  data actually say versus what were people worried about because the conventional wisdom told them to worry about it?

• 44:55Speaker 11

  At some point, I realized that there were things I wanted to tell parents, parents who were interested in data, that were not in the books. And I thought, well, I'll start a newsletter about pregnancy and parenting, and I'll answer questions for parents like, can my kid have juice?

• 45:13PJ Vogt?

  How big a thing is the juice debate?

• 45:15Speaker 11

  People are very interested in the question of whether their kids can have juice. It used to be that people had juice. When I was a kid, people had juice. My brother exclusively drank juice. He drank so much juice. I'm surprised he's not orange. But now you're not supposed to give your kid juice. Juice is verboten.

• 45:32PJ Vogt?

  And how's the evidence on the juice question?

• 45:35Speaker 11

  You know, the drinks your kid needs are water and milk. Your kid doesn't need juice. Juice has a lot of sugar. And so people probably used to drink too much juice. But I think the current generation may be a bit too afraid of juice.

• 45:50PJ Vogt?

  They've become too juice conservative.

• 45:51Speaker 11

  Too juice conservative. Exactly. Too juice conservative.

• 45:55PJ Vogt?

  This is where Emily Oster lives, at least online, telling you not that juice is great or the juice is evil, but instead using her expertise to help you decide how much you should turn the dial on your own juice worries, how you'd like to live your life. Emily's skill is that she helps set these kinds of dials for the parents who read her across all sorts of topics. She looks at the data, she looks at the science, and she tries to answer some version of this question over and over again. Given what we actually know right now about topic X, how do we make the best possible choice about how to live in the world? Her view is that for parents in particular, there's an infinite amount of things they could worry about and they need to prioritize. And given that, and given the evidence,

• 46:39PJ Vogt?

  she isn't yet convinced that microplastics should be at the top of most parents' list of concerns.

• 46:45Speaker 11

  I don't know. I mean, I, I have a sort of a couple of different reactions. I think one is if there are any effects, they are relatively small at the levels we are exposed to. And so there are a lot of other things I would be worried about first.

• 47:04Speaker 11

  I don't think we do a good enough job helping people understand, like, what are the things we really know that you shouldn't do? And what are the things that are kind of like a nice to have? You know, so if someone came to me and they said, "Look, I'm smoking a pack of cigarettes a day and I'm drinking my water out of water bottles. I'm thinking of quitting the water bottle thing because of microplastics." I would tell them, "Hey, you should quit smoking first and like later you can worry about the water bottles, but like the smoking is really bad." And so I think the microplastics are likely not to be, for most people, very important or even the most important thing they could do to kind of improve their overall health, given where most people are. The second thing I would say is that in the kind of space of the stuff we consume, for most people, probably the one strong,

• 47:49Speaker 11

  modifiable, microplastic exposure is disposable plastic water bottles. So if someone said, "I really worry about this. I want to do something about it." I would say, "Look, stop drinking out of disposable plastic water bottles. That's probably like the most significant thing that you can do that is a reasonable change that wouldn't like totally upend your entire life."

• 48:09PJ Vogt?

  And with your kids, do you think about? Their plastic consumption, like, do you make the small marginal edge case modifications or no?

• 48:20Speaker 11

  We don't drink a lot of bottled water, but not for this reason. And I think that's actually a good point, which is that I think there is a question of like, could we limit the amount of plastic we are introducing to the environment, having nothing to do with microplastics? You know, plastic is not good for the environment, is not good for animals in the environment, is not good for the ocean. We produce plastic we do need, but we produce a lot of plastic we don't need. And I think it would be great if we could try to limit the amount of plastic that we consume that we don't need, even if we didn't care about microplastics at all. So in my own household, I guess we try not to consume a lot of water out of plastic disposable water bottles. But other than that, I don't do a lot of the other things that people ask me about. Like, for example, I will run our plastic glasses through the dishwasher, even though

• 49:05Speaker 11

  many people are horrified at that idea.

• 49:14Speaker 11

  There's this question of like, what is the value of worrying? Which, like, my dad, when I started thinking about this, I'd written this long thing in ParentJade about this, partly motivated because my dad was like, well, is this something I should worry about? And I was sort of thinking about that question, and like, I don't like that question, because the answer is almost never you should worry about it. Like, we do worry a lot, but that's an incredibly useless way to spend our time. Really, the question you want to say is, is there something I should do about this? And the answer is like, here's a thing you can do, but then you shouldn't spend your time worrying about it, because worrying is not a productive way to use your day.

• 49:50PJ Vogt?

  It's not productive, but it's like

• 49:51Speaker 11

  Not productive.

• 49:52PJ Vogt?

  So hard not to do.

• 49:53Speaker 11

  Totally. No, I mean, of course, that's like the inherent thing of being a parent, do you spend your whole day worrying about your kids? And there's like, nothing you can do about any of it. You know, how did their math test go? I hope the beach day was fun. It's just like, constantly, but it isn't productive. If you can avoid it, it's better.

• 50:09PJ Vogt?

  I also took this question, how much should I worry about the microplastics in my own home, particularly with kids in the house? Back to Professor Tracy Woodruff. And it was interesting. When I relayed some of the things that our listener, Louisa, had told me her sister was doing, dressing her kids in organic cotton, only using certain pots and pans. Professor Woodruff said she thought those choices sounded reasonable, actually, a lot like choices she makes. She's a professor who studies the toxins in our environment, and she does not put plastic in her microwave or dishwasher. She tries to wear natural fabrics like cotton and linen. She uses a vacuum with a HEPA filter. The question we often want answered from experts is just like, okay, but what do you do at your home?

• 50:53PJ Vogt?

  And the vexing thing here is that Tracy Woodruff and Emily Oster are making different choices, and both seem reasonable. Tracy does not sound to me neurotic. Emily does not sound to me reckless. They're just doing what all of us have to do when we face uncertainty. Make a decision that lets us live our lives today, and that we imagine we could live with tomorrow. Which left me with one last question for Professor Tracy Woodruff. In a world where microplastics are, you know, floating off the tires of the cars on the street outside my house, and, you know, like, rising off my friend's fleece and into my

• 51:33PJ Vogt?

  pores or whatever, I'm curious, like, how much does it really, does being highly scrupulous at an individual level move the needle versus, like, really, this gets solved socially?

• 51:45Speaker 04

  Okay, so, both things are true. You can actually lower your exposures to certain types of toxic chemicals by individual practices. That's been shown. For example, it's well-established that if you eat an organic diet, you will have lower exposures to pesticides. Now, can you get rid of all of them? No, it's like air pollution. You filtered the air in your house, and that works for that.

• 52:12PJ Vogt?

  Right.

• 52:12Speaker 04

  But you're not going to get rid of all the air pollution, because it's also being produced by sources that you don't control, cars, factories, but you do control it, because the government can control them.

• 52:25Speaker 04

  I want people to be concerned at the level that they are telling the government what they care about is that they address these toxic chemicals and plastics, but not so concerned that it makes them paralyzed in their individual life.

• 52:46PJ Vogt?

  Professor Tracy Woodruff. You can find her at the University of California, San Francisco, where she researches and teaches. You can find Professor Emily Oster at Brown University or at her home on the internet, Parent Data. And me, you'll be able to find me this week staring at my plastic water bottle, trying to decide whether or not I trust it.

• 53:42PJ Vogt?

  Search Engine is a presentation of Odyssey. It was created by me, PJ Vogt, and Trudy Pennamineni. Garrett Graham is our senior producer. This episode was produced by Kim Kupel and fact-checked by Clara Hyman. Theme, original composition and mixing by Armin Bazarian. Special thanks this week to Professor Richard Thompson and Oscar Knoxen. Our executive producer is Leah Reese Dennis, and thanks to the rest of the team at Odyssey. Rob Mirandi, Craig Cox, Eric Donnelly, Colin Gaynor, Maura Curran, Josefina Francis, Kirk Courtney, and Hillary Schuff. Our agent is Orin Rosenbaum at UTI. If you'd like to support our show, get ad-free episodes, zero reruns, and for the bonus audio that we're putting out next week, please consider signing up for incognito mode. You can learn more at searchengine.show.

• 54:27PJ Vogt?

  Follow and listen to Search Engine for free on the Odyssey app or wherever you get your podcasts. Thanks for listening. We'll see you next week.

• 54:57PJ Vogt?

  This episode of Search Engine is brought to you in part by VistaPrint. As a small business owner running a podcast, I'm always looking for authentic ways to connect with listeners, which makes VistaPrint such a valued expert partner for us. I was on their site the other day brainstorming new things we could make for our show, and the creative momentum took over. I ended up designing search engine stickers, and I tried to make a sign for our office. When your physical branding looks this sharp and professional, it immediately communicates credibility and shows your audience that you mean business. VistaPrint truly helps every dollar go further, delivering premium quality and design support that make your company look established without breaking the bank. Whether you need your design tweaked or a total rebrand, VistaPrint has you covered with the expert service small businesses deserve.

• 55:41PJ Vogt?

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