The Land & Climate Podcast

How badly have microplastics harmed ecosystems, climate, and human health?

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Bertie talks to science journalist Matt Simon about his upcoming book; A Poison Like No Other: How Microplastics Corrupted Our Planet and Our Bodies.

Further reading: 

Click here to read our investigation into the UK biomass supply chain, or watch a clip from the BBC Newsnight documentary.

Bertie Harrison-Broninski:

Hello, and welcome to the Economy, Land and Climate Podcast. My name is Bertie Harrison-Broninski, and today I'm talking to science journalist Matt Simon. We're going to be talking about plastic pollution, in particular microplastic pollution, ahead of the publication in a few weeks from now, of his new book, 'A Poison Like No Other - How Microplastics Corrupted Our Planet and Our Bodies', which is being released by Island Press.

Matt:

In just some of these protected areas, very small portions of the Western US, something like the equivalent of 300 million plastic bottles fall out of the sky every year as microplastic. It's hard to fathom.

Bertie Harrison-Broninski:

I began by asking Matt to tell us how he got into writing this book and learning about plastic pollution.

Matt:

For a number of years now, I've been covering microplastics studies as they've been coming out for Wired, just online news articles. You know, as I was writing the book, there were more studies, in particular coming out about the atmospheric dynamics here. So scientists have known for a while that these little plastic particles, they're not very dense, they easily take to the air, but there's just been in the past year or so some really good modeling studies that have shown just how far these things are blowing in the atmosphere, they're way up high. They're flying thousands of miles into what we would consider to be pristine environments like the Arctic, or just deep in rainforest. Basically, every inch of the planet now has microplastics raining out of the sky.

Bertie Harrison-Broninski:

Could you take us through macro, micro and nanoplastics? What do those terms mean, and how do these tiny bits of plastic get into our environment?

Matt:

Yeah, so we are all familiar with bottles and bags floating around on the ocean. Those are macro plastics, scientists call them, they're the big pieces. And microplastics, as it's defined, are little pieces that are smaller than five millimeters, was an agreed upon definition. I don't want to say it's an arbitrary number, five millimeters, but what they're actually going for when they were thinking of the definition here was 'okay, we know that sea turtles are choking on plastic bags. But what might other smaller sea creatures be exposed to, when these plastics get much smaller into the microscale?' And then getting even smaller, we start thinking about nanoplastics. And the definition here is a little bit of disagreement in the field. But generally, it's considered once they get smaller than a micrometer, that then becomes a nanoplastic. And that is very, very small. And there's more and more research finding those just in astonishing numbers in the environment, it's just been very hard to detect though. They're so small, it takes a lot of time and money to do that. What we're seeing here is that as more studies come out, there may be an equal amount of microplastics and nanoplastics by weight, meaning that, you know, you could have 10 larger pieces of microplastic, but a bunch of much smaller pieces of nanoplastic in similar amounts in the environment but they're so much smaller that just more of them can get into more spaces, including into more creatures and even into cells. There's two main ways these are getting into an environment. For one, we have those macro plastics breaking into smaller bits as they're floating around the ocean or tumbling over the land. But you also have a huge source of microplastic in our clothing. So when we wash synthetic clothing like polyester, it's all made of plastic, little bits of fiber break off and wash out to a wider treatment facility which then captures some of those, maybe around 90% of those, in this material called sludge. It's not a particularly nice name for not a particularly nice material. It's human waste that's then spread on fields as fertiliser. What we're doing though, is we're capturing all that microplastic in there, spreading it on fields, and that is then scoured by the wind, and that kicks off the microplastics into the atmosphere. And the rest of them that are flushed out to see, the remaining 10% or so, are just increasing in exponential numbers in ocean sediments. It's a huge problem because we don't have filters on our washing machines to capture these little bits of plastic. The other major source is a thing called nurdles. These are pellets, these are the pre-production bits of plastic basically what's melted down to make bottles and bags. Those are very easy to lose along the supply chain. They spill in astonishing numbers and they just so happen to look exactly like fish eggs. So there are a lot of creatures that feed on that sort of thing out there instead ingesting these nurdles and filling up their stomachs and decreasing their appetite for actual food. And that's that's really the primary concern among oceanographers is that we're feeding, we're force feeding plastic to smaller creatures, in just astonishing numbers.

Bertie Harrison-Broninski:

When most people think about single use plastics, they imagine that maybe a whole Coca Cola bottle in pristine form would still be around in 1000 years or whatever. Was that a misconception that you were aiming to try and counter because the problem is so much that they do break down, right?

Matt:

They do. And it's tricky, because you can have the same bottle in two different parts of the ocean breaking down in fundamentally different ways. So the main way that these are breaking down, if they're floating on the ocean surface, you have UV bombardment, and that really does a pretty good job of breaking apart the bonds and plastic. When that happens, it releases all kinds of toxic chemicals to dose whatever living thing is in the vicinity. But when a plastic bottle sinks, maybe it's out of UV radiation, and it's maybe not broken down by that. But as the pressures increase, maybe that breaks it apart. And there's so many different kinds of plastic scientists can't say, 'okay, this takes X number of years to break down in environments, usually a century or 1000 years'. They can't say that for certain, because it's different for each plastic and it's different for each environment. I think generally though, that plastic takes a very, very long time to break down and when it does, it doesn't disappear, it breaks into these microplastics and nanoplastics. And what scientists are still actually looking for is, well, how far does that go? How small do these get? Do they just break down eventually into their component chemicals? And I think the predominant thinking is that, no, they reach only a very small size on the nano scale. And then they're just not really broken apart by friction and things like that. They reach kind of a sweet spot, which is terrible because these nanoplastics are just falling out of the atmosphere in incredible math. There was a study that looked at, I think it was somewhere in the remote Alps, on top of a mountain, if you stood on that top of the mountain for like an hour, there would be hundreds of millions of these nanoplastics falling on your shoulders. It's just a fundamental component of the atmosphere and we don't really understand what that means for every creature on this planet that is now exposed to plastic.

Bertie Harrison-Broninski:

The pollution of remote areas was also something that surprised me. I remember you talked about one study where a reef in Indonesia was more polluted with plastic than a neighboring busy beach. Why do you end up with that kind of situation?

Matt:

In the ocean, you'll get some dynamics with currents. These tend to accumulate a lot of these plastic, you've all heard of the Great Pacific Garbage Patch, obviously, that's a gyre that really swirls around and collects these plastics over time. There was another study you might remember from the book that looked at some currents around Hawaii, where they were sampling within those currents how many plastics are there, how many fish larvae are there, and the tiny plastic particles far outnumber the fish larvae. So you get in the ocean currents are transporting these plastics and accumulating them in these really dense numbers vast distances, 1000s of miles, way into the deep oceans. Some of the highest concentrations in sediment was actually found in the Mariana Trench, which is the deepest you can go, which is incredible and terrifying. There is basically no place on Earth that's untouched. And when we're thinking about the atmosphere, you get the same thing, currents in the sky of air that are accumulating these things and transporting them. But you're also getting an interplay between the ocean and the atmosphere. When waves break, they spit up a bunch of aerosols, and included in that is microplastics. So when you're walking along the beach, that sea spray has plastic in it, and not to ruin beaches for anybody, but unfortunately, microplastic pollution has been out of control for so long, it might be that the ocean has so much of it it's now just spitting more back onto land by way of wind than it's getting from land itself.

Bertie Harrison-Broninski:

One thing I think you do very well in the book is constantly include statistics, pretty much every paragraph has numbers backing up just the sheer scale of this. I mean, we can't really convey that as powerfully in our podcast, but are there any statistics like that that come to mind as just really impactful ones that you think about? And how do you make sense of those numbers?

Matt:

Yeah, how do you on on this scale? I think a really representative one was the study of the atmosphere above the United States. This was a scientist I actually visit in the book. In the introductory chapter, we hike up a mountain and I should say I struggle to hike up a mountain because I'm not an outdoorsy type, but on top of this mountain, she has basically a microplastic capture. It's a bucket that captures everything falling out of the sky; dust particles, but microplastics included. She's done some pretty astonishing calculations, including one where she found that, okay, in just some of these protected areas, very small portions of the Western US, something like the equivalent of 300 million plastic bottles fall out of the sky, every year as microplastic. It's hard to fathom. It's been this invisible problem for so long, but when you put it in terms of bottles I think it makes a big difference. We are dealing with an exponential production of plastic since the 1940s, when production of plastic really began to take off. And as we wean our economy off of fossil fuels, the fossil fuel industry is turning to plastics to make up that lost revenue. Production is going to increase massively; a trillion pounds per year in the very near future of plastic. And that number is even more astounding when you think of one of plastic's charms is that it's so light, like how much plastic equals a trillion pounds? It's an astonishing amount and it's hard to wrap our brains around. And I think what I'm trying to do with those numbers in the book is really put some urgency to this that the big solution to this is just at the very end of the day, we have to stop producing plastic at the scale, all told, just single use plastic is an insane concept. We shouldn't be wrapping cucumbers in plastic, they have their own skins thank you very much. This is gonna require a fundamental rethinking of the way that every human operates, basically. We're all now used to using single use plastic for everything when none of us asked for it, it was foisted upon us. So that's what I'm basically trying to do with these numbers is like, 'look, here's the scale. These numbers don't lie. This is the urgency involved'.

Bertie Harrison-Broninski:

Despite all of those facts and statistics, I think something that also comes through is how much we don't know still, how ignorant I guess we are of this problem.

Matt:

And we don't yet know, for, I don't know, millions upon millions of species, how much microplastic is too much microplastic. We have some lab studies that typically use higher concentrations to try to elicit some sort of response from an organism but there are some others that are using what's called environmentally relevant concentrations, basically concentrations that you would find out in the ocean and they're also showing harm in any number of ways. And I call it 'a poison like no other' because it's plastic, that has used something like 10,000 different chemicals in these and many of which are proven toxic to organisms. But it's also this 3D structure, right, like mercury diffuses out into the environment but a plastic is a physical thing, and it can get stuck in stomachs and fishes. And it can change the way that soil behaves. All these different facets to this in particular, if we're thinking about the atmosphere, these microplastics in the atmosphere are now interacting with sunlight. And there's been some modeling this showing that maybe it's changing the way that the atmosphere is working. It's also maybe acting as a little bits of material for clouds to form on that water accumulates on those as nuclei. Maybe it's changing the way clouds are forming. There's just so many things we don't know, both in the way that it's influencing, potentially the climate, but also, again, every living creature on this planet. It's horrific to think of, especially when we know that there's already demonstrated harm for many organisms. And then the second side is the human health side where we know almost nothing about what these plastics are doing to our bodies, which is especially concerning because where we're exposed most to microplastics is in the home. It's just an incredible amount of the stuff around us is shedding little bits of plastic. That includes our clothing and couches in any number of other plastic objects in our homes. There was one calculation that we are inhaling something like 7000 particles a day probably. And we know from studies of people working in textile factories that they have higher rates of lung cancer, but they also are exposed to way more microplastics than we would be here in the home so that science is just getting started that 'okay, well what is this doing to human health?' And we know that it is in our blood. We know that it's in our lung tissue. They do biopsies of unhealthy lung tissue from folks who didn't work in textile mills, and they're finding microfibers there. So that's the next frontier and I think that's where a lot of the money in research is going is 'holy cow. We've been exposed to these things for decades now, is it potentially behind any number of human ailments?' There are a particular class of chemicals in these plastics called endocrine disrupting chemicals, or EDCs, even in very low concentrations can be very, very bad for human health. At what point do these concentrations become problematic for us, if ever? That is what we'll see probably, maybe take five or 10 years to get definitive evidence. But scientists are extremely concerned because no particulate matter is good for the human, especially one that's made out of 10,000 different chemicals, many of which are known to be toxic to humans.

Bertie Harrison-Broninski:

I found it interesting in the book when you talked about the fact that we don't apply the same standards in terms of listing ingredients to most things as we do to food. And you quoted one scientist saying, 'there's no ingredient list on your shoes, no ingredient lists for your motor oil or for your antifreeze.' Is the research gap that we have partly a result of that lack of corporate transparency? Is that one of the key issues here?

Matt:

It's huge. It's huge. And what scientists have to do is reverse engineer plastics, basically. In a lab, they can figure out which chemicals - it's actually quite difficult, but there are so many different kinds of plastics, like just look around you at how many different kinds of plastics there are, none of which has a label on it, listing 1000s upon 1000s of ingredients in the plastic. And we let plastics companies just give these to us without any consideration for'okay, well, maybe they're getting into the human body?' The scary bit is infants are exposed to just astonishing numbers of microplastics through their feed, through their bottles. So if you prepare formula in a bottle with hot water, that's the perfect conditions for breaking down a plastic and millions of particles potentially getting into infants, and like we don't know, it's crazy to me that we don't know the human health effects yet we're exposing kids in particular, to all these particles. And toddlers as well, they're crawling around on the ground of your home, where on you know, in a typical living room, hundreds of thousands of particles are being deposited each day. It's madness. And we've just let these companies surround us with plastic, there's always been this narrative that plastic is benign, it's totally fine. But there are a number of demonstrated harms from the chemicals in plastics that scientists are also starting to explore the specific chemicals. And I think that's actually what we're gonna see in the coming years and where the tide might turn here is where as scientists develop this body of evidence that this particular chemical in plastic is just terrible for human health and is leading to early deaths, that sort of thing. There's there's been a couple of studies already that have shown that plasticisers are doing that. And the more of that that we get, I think the more the tide will turn and the public will will get angrier and angrier that we didn't ask for all this stuff.

Bertie Harrison-Broninski:

You have touched a bit on this already but could you tell us how plastic pollution contributes to global heating as well?

Matt:

It's carbon, right? It's chains of carbon that come from fossil fuels. And I guess what did we think was going to happen? Right? When when all of this plastic gets out into the environment, it's going to release that carbon. There is one early and very good study that really looked at the amount of off gassing that you get from those particles. And it is a lot. In particular methane, which is, of course, an extremely potent greenhouse gas, much more so than CO2. It disappears from the atmosphere quicker, that doesn't make it any less harmful. But there's just very little research on'Oh, my God, this stuff is all out in the environment in tremendous quantities. It's releasing that carbon. What contribution does that then have to emissions overall? And to return to this point that I tried to drive home in the book is that even as we decarbonise our economy, we'll be producing more and more plastic. I mean, ideally not. But if trends continue, we'll be producing more and more plastic. Every step of that production process releases emissions and there's one calculation that by 2050, the emissions from plastic could be equal to over 600 coal fired plants, which is devastating because we've been making really good progress decommissioning coal plants around the world and decarbonising our economy and we're just going to be pushed in this opposite direction with more and more plastics. Now we're grappling with what are the potential consequences and the microplastic and nanoplastic that's out there, it's out there for good. There's no taking it back, there's no magnet or anything that we can deploy that would suck it all out of the atmosphere, that sort of thing.

Bertie Harrison-Broninski:

There are also a lot of uses for plastic that we probably can't do without now, right? Like I'm thinking healthcare? Are there alternatives for some of the more kind of necessary plastic uses? Or is it just a case of reducing to as small amount as we can?

Matt:

I tried to make it clear in the book that plastic serves very good and real purposes. Like I admit its a miracle material. It's a pretty astonishing thing. It's light, it's tough, and there are, of course, as you say, going to be uses in medical fields in particular, that sort of thing. Cars are lighter because of plastics, lighter and safer, that sort of thing. I'm railing against single use plastics in particular because they're completely unnecessary. So there will be I think room for new plastic alternatives. There's some research on making it out of mushrooms and other kinds of things. The trick here is, and where I bristle a little bit where you hear about, 'oh, we've invented a new bioplastic that breaks down better in the environment' completely discounts the fact that okay, well, it's still breaking into microplastics all the same. And there's, I don't think, really ever any toxicological data on'Okay, well, if that's a plastic by another name, it's probably using the same kind of plasticisers and other chemicals that are keeping it together'. Bio plastics grown from plants are extraordinarily problematic because you're using a lot of land to grow crops to make those plastics out of plants instead of fossil fuels. And a lot of these new materials, if we're not careful, are going to give the plastic industry excuse to keep producing more of it if they can convince us that it's totally harmless when in reality, at the end of the day, I talked to a number of scientists and quote them in the book as saying, 'we've just got to stop with so much plastic'. That is endgame. Everything else is great to have, like recycling is in and of itself problematic but we need more of that. The plastics industry sold us on recycling knowing that it didn't work and to this day, less than 9% of plastics are recycled. In the United States, I think even less now, because the pandemic screwed up a bunch of the infrastructure. So we need to be careful about these innovations that that's not co opted in certain ways by the plastics industry to keep producing more plastic. And we also need to be careful about the toxilogical stuff. If it's breaking into microplastics all the same, you know, what good is it going to do in the end? And then, you know, just lastly, glass is heavier, you know, it's problematic in its own way, it just takes more energy to ship it. But I think there's ways to get smarter about paper, cardboard, grown in sustainable ways, using more of that, in place of plastic, getting more creative banana leaves for wrapping certain perishables. They already do that in Asian markets, in Asia. And I don't know, there's just there's ways to be creative about this that first and foremost is about just stop using so much plastic for God's sake.

Bertie Harrison-Broninski:

My thanks to Matt for coming on the show. If you want to preorder or buy his book, we'll put a link in the podcast description below, along with other further reading that he's recommended on the topic. If you enjoyed this episode, please do follow us or subscribe to us on whichever platform you're listening on. And we'll be back soon with more interesting interviews from climate experts. Thanks for listening.