Ep 133: Microplastics, macroproblems (with Martin Wagner)
What are microplastics and why are they an issue for the environment? How can global policy address plastic pollution?
On this episode, we talk with Martin Wagner, a Professor of Environmental Toxicology at the Norwegian University of Science and Technology. We talk with Martin about the potential harms of microplastics and plastic-derived chemicals to our health and the health of natural ecosystems. We also discuss Martin’s work as part of the International Negotiating Committee set up to produce the UN plastics treaty, a global agreement that outlines steps and timelines for the production and use of plastics.
Cover art: Keating Shahmehri.
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Molly Magid 0:05
Hey, Marty,
Marty Martin 0:06
Hey, wait, you're not Cam
Molly Magid 0:09
Yes, what an astute observation.
Marty Martin 0:11
Okay, yes, I know who you are, of course, but our listeners probably don't. Do you want to introduce yourself?
Molly Magid 0:16
Sure, I'm Molly Magid, and listeners may have heard my name in the credits because I'm the producer of Big Biology. And while I'm usually behind the scenes making you and Cam sound great, today, I'm stepping out from behind the curtain to help you record this intro.
Marty Martin 0:32
Well, excellent, and it's so good to have you here. Have you also brought us a hook for the intro?
Molly Magid 0:37
Yep, have you seen the photograph that changed the world?
Marty Martin 0:41
Um, which one you talking about? The first photo of Earth from Space?
Molly Magid 0:47
No, though that is an important photo. The photo I'm talking about is a vivid depiction of how human activities are affecting the planet.
Marty Martin 0:56
Okay, but I'm still not sure exactly which one you're talking about, there are so many photos like that.
Molly Magid 1:03
Okay, okay, I'll tell you, it's actually a series of photos that artist Chris Jordan took on Midway Atoll of decomposing albatross chicks. Within the carcass of each chick, you can see loads of plastic embedded in what's left of their stomachs.
Marty Martin 1:19
Oh yeah, I do know that one the birds remains are filled with bottle caps and bits of fishing gear and cigarette lighters and all sorts of other plastic objects that we just throw away
Molly Magid 1:28
Exactly. It's such a powerful image both because it's of baby birds, but also it's striking because it comes from such a remote area in the middle of the Pacific, almost as far away from civilization as you can get.
Marty Martin 1:41
And the problem with these macro plastics is just the tip of the iceberg, because most plastic doesn't degrade very quickly, which means that pretty much all the plastic that's ever been made is still present.
Molly Magid 1:59
Yeah. So what killed these albatross could well kill more wildlife over time. That means that plastic pollution is a two fold problem. We need to adjust the ways that we make new plastic, and we also need to deal with all the plastic that's already around.
Marty Martin 2:15
Right and these two problems are largely why in 2022 the United Nations Environment Assembly addressed how to end plastic pollution through the creation of the UN plastics treaty. This global agreement will outline steps and timelines for handling the life cycle of plastics.
Molly Magid 2:31
The International Negotiating Committee set up to develop the treaty is made up of heads of state, business stakeholders, and expert scientists from over 175 countries, including Cam's colleague and our guest today, Martin Wagner.
Marty Martin 2:45
Martin is a professor of biology at NTNU, or the Norwegian University of Science and Technology, where he studies how plastics and other synthetic agents interact with human and ecosystem health.
Molly Magid 2:56
Martin's focus has been on microplastics rather than the macro plastics from the albatross photo
Marty Martin 3:02
Though, of course, micro and macro are related because big plastics shed fragment or are degraded into micro plastics,
Molly Magid 3:10
And because micro plastics are so small living things can easily ingest, absorb or inhale them and be made sick from the many chemicals that leach from plastic.
Marty Martin 3:21
In fact, most of our talk with Martin covers these chemicals and their health impacts.
Molly Magid 3:25
A recent analysis by Martin and colleagues revealed that up to tens of thousands of different chemicals can be present in some plastics.
Marty Martin 3:33
We also discuss what it's like for Martin to use his research to inform policy, including the UN plastics treaty process.
Molly Magid 3:40
And if you're as freaked out about microplastics as I am, Now be sure to stick around until the end, when Martin gives some advice on how best to deal with micro plastics.
Marty Martin 3:50
I'm Marty Martin
Molly Magid 3:51
And I'm Molly Magid
Molly Magid 3:52
And this is Big Biology
Marty Martin 4:06
Martin, thank you so much for joining us on Big Biology today. You're an expert on a topic that we've been wanting to cover for a long time, microplastics. We're going to focus on several of your papers in that area, but let's set up that work using a 2024 paper in Science by Thompson and colleagues. It was entitled "20 years of micro plastic pollution research, what have we learned?" And I think it does a really good job of scoping the problem, somewhat terrifying the reader, to be honest. But let's start very simply, what is a micro plastic?
Martin Wagner 4:37
So microplastics, I mean, it's an umbrella term for tiny plastic particles, right? And there's a lot of conversation in the scientific community about what microplastics actually are, but I think the most important thing to start with is that it's not like a single thing, right? We have so many different types of plastics that we're using on a daily basis. Micro plastics come in different sides. Sizes and shapes and colors and chemical compositions and material properties. So it's really this kind of larger, kind of a large umbrella term for, like, a diverse class of pollutants, I would say. And sometimes I feel the term microplastic was very helpful in forming, like the scientific community, the policies around it public perception. But also sometimes I think it's kind of a boon, because we're just like simply saying micro plastics, whereas we mean thousands of different tiny little particles.
Marty Martin 5:30
Yeah, was the original idea, you know. So there are the mega-plastics, the obvious big plastics that we could see in the environment is just the need for the name of a new term. That's the things that are not so obvious you would have to actively go look to find them. Or is it more the kinds of problems that microplastics cause are different than, you know, the plastic rings on sodas that you see, you know, gulls and other wildlife eating. I mean, what was that some of the motivation to draw attention to a different problem with plastics, or is it something subtler?
Martin Wagner 6:06
Oh, that's an interesting question, actually, and something I haven't really thought about a lot, but I think, first of all, there's a psychological touch to it, right? Because if you call something micro, it's kind of invisible, it's kind of you people perceive it as an invisible threat, as opposed to what we call macro-plastics, which everybody's seen on the beaches or wherever you go. So it has this kind of psychological touch of, oh, there's something threatening about these small, little particles. But then indeed, of course, the idea is that the smaller plastic pieces items get, the more likely is that animals were ingested, the more likely these particles are to translocate across biological barriers, into bodies, etc. So of course, there's some specific kind of concern about smaller pieces of plastic. And then lastly, it's just so many more compared to macro-plastics, right? Because of the fragmentation, etc. So it's just you get many more micro, nano plastics than macro items, right?
Marty Martin 7:04
And these are, this micro is sort of on the five millimeter scale. I think that I remember reading that was one of the, sort of the numbers, just to give the listeners a perspective on when something starts to be on the micro scale.
Martin Wagner 7:17
Right, so it's quite contentious discussions about sizes. And I don't know why microplastics researchers are so obsessed with size. Size does matter, indeed, but we've had so many conversations. Should it be five millimeters? Should it be one millimeter? I'm in the one millimeter camp,
Marty Martin 7:34
Ok
Martin Wagner 7:34
Because that's just, you know, more tidy in terms of standard units. But the five millimeter really originates from a NOAA workshop in the 2000s and I think the idea was to cover plastic pallets, nurdles, pre production pallets, which researchers back then already knew that were ingested by sea birds, for instance. So to cover these slightly larger microplastics, the NOAA workshop concluded it should be smaller than five millimeters, just highlighting it's totally arbitrary. It's a total arbitrary definition, size definition.
Marty Martin 8:07
Ok
Cameron Ghalambor 8:08
Yeah, so, so Martin the I think everybody is aware of the macro plastic problem. They've seen pictures and images of rivers and lakes, you know, covered with plastic bottles and bags and everything. But the these, these microplastics, the ones that we can't see, at what point did we realize that these were actually creating a problem that, you know, had not been recognized before?
Martin Wagner 8:39
Well, I mean, like the term, as you said, came to life in 2004 with Richard Thompson's paper in Science, where he coined the term microplastics, really. And they just did surveys along the coast of the UK, and they found microplastics in all their plankton samples. So that's how it came the term itself came to life. But indeed, we know about microplastics for much, much longer. First paper dates back. I've been trying to trace it, late 60s, early 70s. So Ed Carpenter, and that's really an interesting story, was one of the first people to find plastic pallets in the Sargasso Sea. And I reread his paper recently, and it was so illuminating, because he talked about all the problems that we're still, still kind of grappling with, right? He said: "So we'll likely get more of these plastic pieces. In the future, there will be harmful chemicals attached to those little plastic pallets that he found, PCBs." He talked about, back then, polychlorinated B finals, very, very nasty pollutants. He talked about, like, colonization of those pellets by microbes. And now we talk about antibiotic resistance, you know.And I was just struck by the fact that Ed Carpenter back then already had, like, on the radar all the issues that would be associated with microplastics
Martin Wagner 9:58
Now the interesting. This is like what happened between 1972 and 2004 and I call that the microplastics winter, because no no research whatsoever on the topic. There was a bunch of papers, four or five papers in the 70s, late 60s, early 70s, and then the topic got completely lost somehow. And I think that's a quite interesting phenomenon, with regards to scientists really not following up on early warnings. And I think there's multiple reasons for that microplastics winter, the most prominent one, and Ed said that in a podcast interview, actually was intimidation by plastics industry. So he said he got, he got visits from representatives of the US plastics industry that intimidated him.
Cameron Ghalambor 10:46
Wow.
Martin Wagner 10:47
And he then, and he said, I quote him. He said: "I didn't have a tenured position, so I was in very precarious situation, so I decided to not follow up on that research." So even, like the plastic industry intimidation has been there since the beginning, and that's something that we can talk about later, but it's still there today.
Marty Martin 11:07
Wow. Can you say something more about where these things come from? Because I think the natural intuition is these big plastics we talked about, and eventually they're going to break down, and some of those will become micro plastics. But it's far more than that, right? I mean, there's all sorts of these very tiny forms of plastics that are used in a lot of different products. So what are the predominant sources?
Martin Wagner 11:30
Right I think, like when, when people think about micro plastics, they usually first of all think of microbeads used in cosmetics, personal care products, rinse off products, you know, scrubs, etc. And we call these primary microplastics, or intentionally added microplastics, right? And even though they're still used widely across the globe, not so much in the US and in Europe because of bans and regulations and voluntary kind of measures, they're still kind of abundant. But these make really these make up a tiny fraction of all the microplastics in nature, right? I mean predominant source, as you say, this, is wear and tear of plastic items while we're using them. Textiles would be a good example, right? So textiles, synthetic textiles, shed a lot of plastics fibers while we're wearing them, and then they end up in the atmosphere and we inhale them in indoor air, but also outdoors. Tire wear particles are another big source, right? Also intentional use of tires. Of course they we wouldn't, wouldn't be able to drive without them. But then the use of tires creates a lot of tire wear, which is rubber microplastics, basically. And then, like, that's from intentional use. We call those secondary microplastics. But then you also have like the degradation of plastic items in the natural environments, which do release a lot of nano microplastics, but we really don't understand very well what release rates are, what how long degradation of these items and break down to nano micro plastics takes depends on the plastic type, etc. Probably takes decades, but I would say the predominant source really is like our use of plastics and abrasion and then degradation in nature
Cameron Ghalambor 13:10
So we have these different sources of microplastics, and they are distributed in the environment, and we become, we get in contact with them. And so what do we know about just broadly, some of the the major problems that are associated with these, with these very small microplastics for human health or for the environment,
Martin Wagner 13:39
It's a surprisingly large set of kind of impacts that these tiny particles can have, right? I mean, the most obvious one is what we call physical impacts, or physical toxicity, right? So in the simplest form, think about organisms ingesting those microplastics. They mistake them for food. They're not getting any kind of nutritional value from them. They get a false sense of satiety, and then we look at what we call food dilution. So it's basically just starvation that happens from those microplastics. We see other physical impacts in terms of small particles crossing membranes, crossing biological barriers in the gut, for instance, passing through into translocating into tissues, and then what? Then we get inflammatory processes. Because, of course, the immune system will respond to these particles try to get rid of those particles. It's not bacteria, it's not a virus. So it can't really deal with these really persistent, tiny pieces of plastic. So inflammation is one of the very prominent kind of impacts, if you think about vertebrates and mammals in particular. So we have the set of kind of physical issues. Think about small zooplankton as well that gets entangled in plastic fibers, something that we're seeing in the lab right when we're doing experiments with plastic fibers in our Daphnia magna, you know, they just get entangled in the fibers reduces, like, mobility. They need to spend more energy on, kind of getting of the plastic fibers. So, so it's more like an energetic, physical impact there.
Martin Wagner 15:11
But then we also have chemical impacts, right? I mean, plastics contain this, like, plethora of chemicals that they can release. And the idea is, then, of course, ingestion of microplastics would facilitate that release and then the uptake of those chemicals in the body. On top of that, plastics do accumulate pollutants from nature, as well, so you get like these really chemically loaded tiny particles that could then induce chemical toxicity. But there's also much wider which I would call indirect impacts of microplastics more on an ecological or system scale, right? So microplastics have been shown to affect the carbon pump in the ocean, right? It reduces the sinking rates of fecal pellets of zooplankton, an important pathway to bring carbon down to the sea bottom, to the sea floor, and they can, really can interfere with that process, right? Microplastics are, there's speculations and early indications that they, in the atmosphere, contribute to cloud formation. So there might be impacts on climate systems. There's been a recent study that looked at the impact on photosynthesis on a global scale, and they estimated that microplastics in the atmosphere could reduce photosynthesis and crop yields by 20%, if I remember correctly. So we've get all these kind of indirect impacts that are not really, you know, I'm a toxicologist,but I want to know what the toxicity of stuff is, but we get all these ecological impacts that are really kind of not well understood, but give a lot of cause for concern. And I'm lecturing and stopping there.
Marty Martin 16:43
Well, this is all great information, terrifying information that the diversity of effects. I mean, it's wow, photosynthesis and cycling in the ocean, before we move to where these things are common and or problems you've alluded to some of that already. I want to stick on the human health dimensions a little bit, and we're going to dig into the toxicological research that your lab has done in just a minute. So what are the sort of perspectives right now in the medical community about the influence of micro micro plastics on non infectious disease? Is this something that's getting a lot of attention? I know, and I don't want to steal thunder for later, that there may be some reason to worry about it with regard to obesity and diabetes and these kinds of things. But what's the current thinking?
Martin Wagner 17:30
So I think, like the common narrative in the scientific community is that there's still a lot of things we need to understand with regards to human health. But you know, as a biologist and an environmental toxicologist, I have seen all those studies on all types of animals, and then I always think like, why do humans believe they're so different from all kinds of other species? So I think there's a lot we can learn. You know, from all the experiments that have happened in fish, there's a bunch, tons of rodent studies on microplastics that point towards adverse impacts on reproduction, male and female reproduction, sperm quality, sperm counts, for instance. There's good animal data on inflammation and immunological kind of diseases coming from rodent studies that are also kind of mirrored by fish studies. So there's kind of a, I think, like the evidence is converging to certain type of impacts, but to me believe somehow we are different and we need to have more data. I would say, you know, we've been through phases of research in microplastic science, and we started, all started in the oceans. You know, everybody started to look for plastics in the oceans, and then we moved to freshwater. That's something that I did and I was very interested in. So we moved through different kind of phases. I would say, then it was tire wear particles, then it was plastic fibers. And now, I would say we are in the age of human health impacts, so we're seeing a lot of new research on microplastics and human health. And I think that's good, because it's quite a powerful motivator for people to consider change being a very egoistic species. There's a lot to uncover, but I think there's a lot of early evidence from the rodent studies, but also from human studies that give cause for concern.
Cameron Ghalambor 19:13
Yeah. Huh. So, so Martin, I think that's really interesting. You know, kind of the chronology of like first looking in water oceans, and then, you know, lakes and rivers, and then moving to terrestrial systems. Do we have a sense of how common or abundant these microplastics are across these different kinds of environments? Are they more common in water than on land? Or do we even know whether there's a difference in the abundance?
Martin Wagner 19:46
First of all, I won't say I got into this because I was so annoyed with marine biologists like thinking about rivers as pipelines transporting plastics to the oceans. And they saw some of them said, I don't, I don't want to challenge my colleagues. But some of, some of. Them still think, like, oh yeah, these are just these pipelines that bring all the plastic waste into the oceans. And I'm a freshwater person, so I really love rivers. So I think it's good that we broaden the horizon, in a way. And as you said, like, I mean, there's more research on microplastics and plastic pollution in terrestrial systems and soils and freshwater. Now we're learning about the atmosphere, and what we can see, indeed, is that there's a gradient in line with the history, right? So there's more microplastics and freshwater systems compared to the oceans, and there's much more microplastics and soil compared to freshwater systems. I'm not sure about the atmosphere, but we the more, the smaller particles we study, the more particles we find in air as well. So I think there's this interesting kind of gradient there. But what is quite clear from like, hundreds and thousands of studies even, is that microplastics is ubiquitous, right? I mean, it's a sad truism to say it's from the deepest ocean to Mount Everest. It's from from the Arctic to Antarctica, everywhere scientists have looked for micro plastics they found them-in food, now we're learning about micro plastics in the human body. So it's a sad truism to say we've plasticized the world and including ourselves.
Marty Martin 21:16
So I mean not that we need to add another negative dimension to plastics, but you know, you start with the mega-plastics, and then you end up in this space of new problem with microplastics. Based on what you were saying earlier, we, I think you're indicating that we don't know nearly enough about rates of degradation, or kinds of degradation, or, you know, the varieties across environments, and how those rates and types might change. But do we have any reason to be excited anyway, innovative, wise of actively degrading these or has there been a discovery of natural organisms that have the propensity to help us with this degrading? Yeah,
Martin Wagner 21:56
I think it's like the need of humans to find technological fixes to problems we've caused. I'm critical about techno fixes, to be honest, there there's been kind of intensive research, more coming from biotechnology into designing specific enzymes that would be able to break down certain plastics. So there's kind of famous cases around what's called PTAs. So that's designed enzymes that can break down PT plastics, for instance, coming from bacteria that were cultured from dump sites, basically. So they had time to evolve to to kind of develop specific sets of enzymes to break down synthetic polymers, which are incredibly stable, and we made them to be incredibly stable, right? I mean, that we need to keep in mind, we designed plastics to be durable, and now that turns into persistence, which is an environmental problem. There's other sets of research looking into like insects, wax moths have evolved to degrade honey combs, so they have specific sets of enzymes. The larvae feed on honey combs. So they have specific sets of enzymes to degrade waxes, which are quite similar to synthetic polymers. So they possess a set of enzymes to break down polyethylene plastics. The larvae create a lot of microplastics in the process, right? Because they're chewing on polyethylene bags, shopping bags, for instance. What I would say is that there's kind of, there is a scope for these kind of biotechnological solutions to the problem. But currently there is no way of scaling that technology. We don't have the infrastructure, and then we don't have like economic incentives to have such solutions on top of it. And that makes that's part of, like, the wickedness of the plastics problem, really, that, you know, making new plastic, making virgin plastic, is so incredibly cheap that it really kind of prevents all other solutions from being developed at scale, or being economic at scale.
Cameron Ghalambor 23:57
So, you know, I think a lot of our listeners are familiar with the idea that small things, small particles, will often become magnified at higher sort of trophic levels in the environment. And so, you know, if there's a pollutant you know might be, you might find it in the algae, in the zooplankton, but then it gets concentrated in the fish, in the small fish, and then in the bigger fish. And then, you know, big fish are full of, like, heavy metals and other nasty things because of this. Do plastics behave in a similar way, like if you were to go measure a shark that's at the top of the, you know, the food web, and would it have a higher concentration of plastics in its body compared to, say, a small fish.
Martin Wagner 24:48
Right so that's like we talk about that last bioaccumulation and biomagnification, right, of pollutants, and that's something that's very well described for policing persistent organic pollutants, PCBs, again. And PVDs, etc, Pops, but there's no good evidence for micro plastics to biomagnify across food webs. But there's that's why we always kind of coin it or frame it in a different way, because there's evidence that really supports the idea of what we call trophic transfer. So of course, microplastics will transfer across the food web, you know, let's say, from soup plankton to fish. There's interesting studies, observational studies, on fish to seal transfer of microplastics or so, the seal population feeding on a specific fish species that has microplastic ingested will also get the microplastics via eating the fish, basically. But there is no good evidence showing that these kind of levels build up across the food webs. So that's why I'm careful to not speak about biomagnification at that point. But for sure, we know that micro plastics do transfer across food webs, you know, by a prey.
Cameron Ghalambor 25:56
So why is it that these small microplastics don't biomagnify? What it would seem like, intuitively, to me, it would seem like they would have a similar sort of behavior. But what is it about them that makes it different?
Martin Wagner 26:13
Well, first of all, I think I would say it's challenges in doing that type of research right to demonstrate biomagnification, you need to analyze microplastics in the body of the organism, and that's incredibly difficult. So most of the studies we have is on, you know, microplastics in the gut of the fish, microplastics in the stomach of a beached whale, right? So it's technically the outside of the organism. So that's why you technically can't talk about my biomagnification, but we do know that, you know, from the gastrointestinal tract of a fish, it transfers to the gastrointestinal tract of its predator. So that's why I would say we lack the data on internal concentrations of microplastics, right? Because it's just incredibly hard to analyze those tiny pieces of plastic in biological samples, and that's one of the major challenges, I think, in that area of research
Marty Martin 27:10
Is that a problem of technology that has been sort of resolved in lab mice, where you can put the mouse into the machine and make the measurement, or is it just the absence of an effective technology at all?
Martin Wagner 27:25
Well, we do have, and that's like really a lot of advances that we've seen over the past 20 years. So I mean, analytical chemists are incredibly good in developing new technology or tuned technology, to analyze those particles, yet it's incredibly difficult to analyze in biological specimens, because you have, like all the matrix, you have, like all the you know, you have the tissue, etc, that you need to get rid of. You need to digest, like, all kind of organic material, but you need to preserve the plastic, so digesting a tissue with and preserving plastics which is also organic is quite difficult. So I think it's kind of a technological methodological issue in that regard. But then think about it's also incredibly difficult to get biological samples once you move across like the food web to higher traffic levels, right? I mean getting polar bear samples for analyzing microplastics which are not uniformly distributed in the body, right? If you want to analyze chemicals, you take a blood sample and you analyze the chemical, or you take some fur or feathers from from animals and analyze those chemicals, whereas microplastics, you you would need to digest the whole polar bear, if I could say that, and then not suggesting to do that, to figure out, like when to figure out where the microplastics
Marty Martin 28:42
This is not research we want to do, right?
Martin Wagner 28:45
No, not at all. So there's challenges in quantifying those particles, but I think, like what research has shown over the past two decades, for sure, is that, like every species that has been looked at, has ingested microplastics. It's more than 1300 species now reported to have ingested microplastics, and that shows us that exposure is ubiquitous.
Marty Martin 29:13
Let's talk about a dimension of microplastics that you've done a lot of work in, and we've only just briefly alluded to, in this sort of, these endocrine-disrupting, toxicological effects. Maybe, before we jump into the details, could you say something about the many, many, many different chemicals that are in plastics? Which ones are there? Which ones are most problematic, and maybe most importantly, why are so many of them there at all?
Martin Wagner 29:40
Yeah, that's a good question. So we did a big report on chemicals and plastics last year, State of the Science Report, where we kind of tried to figure out and map, like, what are all the plastics we know about in chemicals we know about in plastics? And that's important in the human health context, right? Because we know that. We get a lot of chemical exposures from using plastics, and we figured out that there's more than 16,000 chemicals that can be used or present in plastic, which is an incredible number. We're not saying that all of these are necessarily used, because we really lack transparency around which chemicals are actually used in plastic, because basically, manufacturers are not obliged to disclose which chemicals they're using, and that results in us using plastic products that we don't have an idea of what the chemical composition is. And that's the research that we're doing. We're trying to reverse engineer and figure out forensically which chemicals are used in those plastics to then, like, you know, figure out what, what would they have impacts on humans actually be? So it's more than 16,000 chemicals we know of that can be used in plastic, and it's so many that was your question, because the supply chain is indeed of plastics is quite complex and quite kind of fragmented. So we have thousands of small companies that each produce their own chemicals to add to plastics. And I think that really drives the complexity, because every company needs to patent their own flame retardant. And that leads to kind of a multiplication in flame retardants, even though it's just one single function we want, we don't want the plastic to burn. So we would need, like one, one chemical or two or ten chemicals for that, but instead, we have hundreds of them.
Marty Martin 31:24
What are some of the examples that we sort of know about historically as consequential, or maybe need to start thinking about as problematic, especially that latter case, I want to talk about this paper that Sarah Stevens led in environmental science and technology in a minute. So we could maybe set that aside. Historically, what are the chemicals in plastics that have been the most concerning?
Martin Wagner 31:46
I mean, I would say the most iconic plastic chemical is Bisphenol A, and there's been a lot of public conversations around that chemical as well. Bisphenol A has been used as monomer to make polycarbonate plastics, baby bottles, mostly, that's why it's so sensitive. And there's decades of really strong, robust research showing that it's an endocrine disrupting chemical, and that basically means it kind of messes up our hormone system. It messes with hormone signaling, hormone action, and indeed, Bisphenol A was designed as a synthetic estrogen used for contraception in the 1930s; it wasn't a very, very efficient contraceptive. It was still a very potent estrogen, though, and then it had to go somewhere, and then somebody figured out you could make plastic from it. So that's how it came to life. So it's a bit incredible to me that we had to spend millions of research dollars and showing that it's an endocrine disrupting chemical. But as I said, like there's, really robust evidence linking Bisphenol A, you know, from animal studies, from epidemiological studies, linking it to all kinds of reproductive developmental neurological outcomes, so that that would be the most iconic, and I would even say the best research chemical at all. But there's also, you know, phthalates that are used as plasticizers to make plastic soft. There's PBDEs that have been used as flame retardants now replaced with organophosphate flame retardants, which are also very toxic. So we have, like, I would say, out of the 16,000 we have like, dirty dozens or dirty 20 of chemicals that have been really well studied over the past. And I'm more concerned about all the other chemicals that we are exposed to which people haven't looked at with regards to their health effects.
Cameron Ghalambor 33:28
Yeah, so Martin, I think a lot of us have seen these, you know, water bottles and other kind of plastic products that say they are BPA free. So this is referring to the Bisphenol , I think what do you think about that? It would seem like a good step in the right direction. But then, if there are all these other chemicals also present that we know very little about, is that just public relations, or is that a really positive step towards, you know, protecting people's health?
Martin Wagner 34:09
Well, on the positive side, I would agree, right? I mean, especially in the US, like companies, have responded really quickly to consumer concerns and just switched out polycarbonate baby bottles, replaced them with other plastics, etc. So that's a good thing. The issue with like the BPA free label is that oftentimes companies just switch to other bisphenols, so chemicals that are not Bisphenol A but Bisphenol S or Bisphenol F or Bisphenol Z or Bisphenol AF, there's a bunch of other bisphenols that have been used as what we call regrettable substitutions, because the chemical structure is very similar to BPA, to the Bisphenol A, but there is no research on the health impact, so they can keep marketing them. And now research emerges that shows, well, similar structure, similar health impacts. So these are regrettable substitution. And that's why I sometimes think the BPA free label that we sometimes like on our water bottles isn't really telling the full story. And on top of that, there's all the other chemicals that are unknown, very poorly kind of tested and assessed, claiming, I've seen labels saying BPA free, 100% safe, and I would say that's a false claim that's not in line with the evidence.
Marty Martin 35:22
Okay, this, I think, is a good time to talk about this paper in Environmental Science and Technology, again, led by Sarah Stevens, and the focus was on what you called metabolism disrupting compounds, of which Bisphenol A is and its variants are one of them, because of its actions through this estrogen receptor Alpha. But I thought, I mean, there's so much creativity to this study. It's a gigantic study. Maybe you can just give us a synopsis of your motivation, a little bit about the experimental design, and then we'll spend most of our time talking about the ramifications?
Martin Wagner 35:57
Right, so, I mean, I talked about, like, reverse engineering, a bit like of forensically figuring out which chemicals are actually used in plastics or present in plastics, and what are the health impacts of those chemicals, right? So in that study, and we've done a series of related work, we basically go to supermarkets, we buy a lot of plastic products. We focus on what we call food contact materials, so plastic packaging, first of all, because that's a major source of our exposure to these chemicals, right? So they're not covalently bound to the plastic, so they can migrate, they can leach into food, into water, and then humans ingest a major, major source of chemical exposures in humans. So what we're basically doing is like, we're migrating and we're leaching those chemicals from all types of plastic packaging, and then we do what we call whole micro-toxicity testing, fancy term for using the mixture of all these chemicals that are coming from an individual item, putting them in cell cultures or other test systems, and then we're looking for like specific toxicological effects. And in that study, we did gather products from multiple countries. That was important to us, because before we only had looked at local products, and we wanted to understand if other countries with stronger regulation and stronger safety rule maybe perform better. Spoiler, that's not what we found. So we're doing toxicity testing, and then we're trying to figure out, like which chemicals are actually in there. And that's quite fascinating, because we're seeing so many chemicals leaching from from those plastic items, which is kind of surprising, I would say, in a rather neutral way, but we find, on average, about a hundred chemical features per plastic product, and that just tells us about the complexity of the challenge that we're facing, right? Yeah.
Marty Martin 37:52
So what I thought was, I mean, as a bit of an endocrinologist myself, what I thought was equally impressive and worrisome is that, you know, it's not only that these estrogen receptors are activated by a lot of these chemicals. There are other receptors really important in especially energy metabolism, that are affected even more. And I mean, in I didn't know a lot about the sort of activation of these receptors by, you know, in a general sense. But maybe you could talk a little bit about these other receptors and the implications of their activation by the chemicals you detecting?
Martin Wagner 38:28
So in terms of, you know, there's in terms of history of endocrine disrupting chemicals, researchers, including us, have focused on interference with estrogen receptors and estrogen receptor signaling, androgen receptor signaling, right? There's a lot of chemicals that inhibit the androgen receptor thereby causing feminizing effects in male animals, including humans. And yeah, that's pretty much like the focus was the focus of endocrine disruptor research for a while, but we started looking into other types of hormone receptors. So in this work, we looked at what we call PXR, pregnant X receptor. And we did use the PRX as well. The biological function is as xenobiotic sensor. So it really senses, kind of all kinds of pollutants, and then kind of triggers our xenobiotic metabolism. So that's its original function. But as these receptors do, they have multiple functions. So PXR is also really strongly linked, linked to to metabolism of glucose and lipids, for instance. So there's kind of this intricate endocrine system at play that has like effects, like all kinds of physiological outcomes. So we looked at PXR, and we found that almost all of the plastic products we looked at had chemicals that would activate that receptor.
Martin Wagner 39:45
And then, more specifically, we also looked at another receptor, PPR gamma, which is the peroxisome proliferator receptor gamma. There you go. Yeah, let's call it PPR gamma. And people are gamma is really like the it's thought of as like the key regulator of metabolism, and we found that chemicals in plastic would also activate that receptor. And that gives rise to this kind of obesogen hypothesis, or hypothesis that synthetic chemicals could kind of contribute to overweight, obesity, metabolic disorders such as Type II Diabetes, and there is a strong inter linkage with endocrine disrupting chemicals, but it's kind of separate, because it really focuses on outcomes in terms of metabolism, not so much in mechanism of action. So what we're seeing is that, like those chemicals in plastic food packaging, do actually activate those, those specific receptors linked to metabolism, and that gives rise to the idea that it's not only the content of the food packaging that might contribute to obesity, right, if it's crisps, etc, high caloric diet, but it's also the chemicals migrating from the plastic packaging itself. And that's kind of telling, because you know people, you know the usual story we tell ourselves about metabolic disorders is always like, we eat too much, too many calories, we exercise too little, and that's why we end up with all these obesity and associated problems. But I think what we've seen on an epidemiological level is that there's always a factor that is unknown that contributes and chemicals, synthetic chemicals might, might be that an unknown factor that contributes to the obesity epidemic that we're facing, not only in the Western world.
Marty Martin 41:35
Yeah, I thought that. So, you know, I don't know how many listeners are familiar with their have recently had an endocrinology class, but we call these receptors, which implies that there's some kind of special lock and key. You know, they're only going to get activated when the right steroid or the right whatever hormone it is, binds this receptor. But you know, they're just proteins with a particular structure that if something bounces into them and attaches, they can get activated. And I thought that, you know, you had 36 different plastics in this study, and the chemicals from 23 of them activated this, you know, master regulator of adipogenesis. Right, so it's amazing that a large fraction of these plastics that you just sort of ran around the grocery store grabbing have this propensity to fundamentally change metabolism. Like you say, it's not just the food that's in the packaging, it might be the packaging that's changing our metabolism. That was, it's remarkable, not just that it happened, but, my gosh, the magnitude of the problem was super surprising.
Martin Wagner 42:37
Yeah, that's right. And I mean, we did, we did other studies where we indeed showed, I mean, we did show like activation of PPR Gamma as kind of regulator, but we did other studies where we indeed show that if you use what we call pre-adipocytes, so that's precursors of fat cells, and you expose them to similar leachates of plastic packaging, you actually differentiate those in fully mature adipocytes, and they also reprogram to really proliferate, so you get many more fat cells, and those fat cells accumulate tons of triglycerides or fats, many more than control fat cells. So that tells us that the activation of that receptor also trickles down into downstream effects on actual fat cell proliferation, size, morphology, etc. So we are seeing in vitro that it also has downstream effects that is quite kind of strongly linked into obesity later in life. And we need to keep in mind, you know, it's all developmental exposures that matters. Fat cells are programmed in early life, even in neutral. So when, when you hit the fetus with those chemicals and you reprogram the fat cells to proliferate and accumulate and crave for more fat, later in life, that individual will be prone to obesity, no matter how hard they train
Cameron Ghalambor 43:54
So, Martin, you mentioned a little bit about, you know, taking these different types of plastics from different different countries, different sources and breaking them down in reverse engineering to kind of what see exactly what was inside of them. But you know when, when you go to the grocery store, you see lots of different kinds of food packaged to different degrees? Do we know the degree to which some of these chemicals vary in their ability to transfer and leach into the actual food themselves. Because obviously, when we, when we take our food out, you know, we remove the packaging and we throw it away. Do we know how much is actually ending up in the food?
Martin Wagner 44:41
So I mean, process of migration is physically quite well. You know, governed by basic laws. Phase law, for instance, is governing like how chemicals would migrate from one solid phase to another or to a liquid phase as well. So, in theory, you could even predict migration behavior of these chemicals, if you would know them. Now the caveat of all this is we try, when we're trying to identify all these chemicals in plastics, typically, we can identify about two to ten percent of those chemicals. So let's say the majority of those compounds remains unknown, and that's another analytical challenge, right? Because identifying unknown chemicals is quite, quite a task to do even, you know, and you don't have, like, pure compound that you can shove in an NMR, and then it just tells you the structure you have this mixture of hundreds of chemicals that is really not pure, low quantities, etc. So that's really a challenge. And I think, like, instead, as much as I like to do this kind of detective work of figuring out which chemicals activate the estrogen receptor, or PPR Gamma or PXR are super fascinating. But I think the easy solution would be to force manufacturers to disclose which chemicals they're actually putting in the plastic. That would be much, much simpler, just on a side note cam, because you said like, well, when you come home with your groceries, you just unpack it. But I mean, there's been storage before, of course, while, during which the chemicals will migrate. And one thing that we often forget about is other food contact materials, right? Most of the food that we eat is heavily processed, and most of the items, the equipment that's used for food processing, is plastic. So there's a lot of contamination happening during the processing of food, which is basically a black box, because nobody's going into these companies getting plastic and testing it.
Marty Martin 46:39
So I think we want to turn to policy. You know, you said that a very valuable thing would be that companies disclose the identity these chemicals. And let's just say that at some point that happens. Unless something else changes, we're still going to be challenged with these thousands of different chemicals. And I know the Food and Drug Administration in the US, or at least it used to be the case that, you know, there's an upper limit on how many per year can be tested to have toxicological effects. And then, even when those tests are really well done, you know, there are limits on the ideal study. One of the things that you allude to is that most of the designs are high acute exposures to these chemicals, whereas, you know, oftentimes humans, we would worry about lower chronic exposures. Those are more difficult, more expensive studies. This is all the run up, Martin, to say, if I gave you nearly or let's go ahead, take it infinite money, and you want to design the ideal surveillance mechanism to try to figure out which are the most toxic, nasty things that humans are being exposed to. How do you go about that?
Martin Wagner 47:47
Okay, I feel like I'm in a PhD eval by now.
Marty Martin 47:53
We will send a certificate at the end of the conversation.
Martin Wagner 47:56
Marty, can I say, give me the infinite amount of money, and I figure it out? I'd like to see that, that bucket of gold. But no, seriously, I do where to start. So first of all, and we should not go, we should not go into the detail of safety testing of chemicals, because honestly, I would say it's a mess. A lot of the methodology is based on ancient science that's been developed in the 14 1940s 1950s 1960s regulators have been trying, but have been challenged by keeping up with latest developments in science and testing and methods. Endocrine-disrupting chemicals are a perfect example. A lot of the regulatory testing that happens doesn't cover endocrine disrupting effects on reproduction, as you say, low dose chronic exposures, etc. So let's say there's a considerable gap in safety testing and chemical regulation, simply because, like those regulations haven't kept up with evolving science.
Martin Wagner 48:59
Second of all, there's a capacity problem, as you say, right? There's only so many chemicals you can assess and test in a given time. Testing is very expensive,requires, you know, a lot of resources to do and time. And you know, think about the 16,000 chemicals and plastics that we know about. Now, in our state of the science report, there is more than 10,000 chemicals that have not been assessed for their safety. And that speaks to governments lacking capacity and testing all these kind of chemicals. And that's why I think the European approach to chemical safety is kind of interesting, because they flipped around responsibilities, right? Whereas in the US, the FDA or the EPA needs to demonstrate that the chemical is a problem. In Europe, the manufacturer needs to demonstrate that the chemical is safe before they put it on the market. And I think that's a very smart paradigm shift that the EU did there, because then basically that has resulted in many harmful chemicals disappearing from the European market, because it just wasn't worth investing and testing them, because producers already knew it would never get approved. So changing like policy frameworks around it, I think, is a much better way than trying to fix an old system that has failed us in terms of chemical safety for a very long time, I would say.
Marty Martin 50:14
Yeah, okay, well, good, you passed your dissertation example.
Cameron Ghalambor 50:20
Well, that's maybe a really good place to transition to talking about how we translate these kinds of biological impacts into policies that will have beneficial effects for the environment and human health. And this is an area that I know you've also been very active in Martin. And so the next, I think, Intergovernmental Negotiating Committee for an international plastic treaty will be meeting in a few months in Geneva, and will be representatives from, you know, hundreds of countries, there will also be representatives from the fossil fuel industry, maybe environmental groups, all trying to have some influence on on the outcome of these negotiations. So you talked about this contrast between the European and US model for regulation. Can you just give a little sense of what would, what would a global plastic treaty include? What would something like that look like? I suspect it's not going to be eliminating all plastics tomorrow, because that's probably not feasible, but what would such a treaty likely include?
Martin Wagner 51:49
Yeah, that's a good question, and I think that's a question that governments across the globe are grappling with at the moment, right? But I want to take us back three years now, where the United Nations Environment Assembly decided that they want to end plastic pollution, and they want to what they want to protect the environment and human health from from the adverse impacts of plastic and plastic pollution. And that was actually a historic moment, because all countries agreed that they want to end that problem. And I still get, I'm still getting some goosebumps when I think about it, now three years later, as we are in the midst of the policy process, and we see it's being watered down, and it's being kind of been delayed, and it's been kind of, yeah, you know, it's becoming difficult. But you know, when I think back about that time where all governments agreed that they wanted to end an important environmental problem, I think that gives us hope.
Martin Wagner 52:45
And a good treaty that would really protect human health and the environment from plastic pollution, would have a set of measures. We've seen a lot of token politics around microplastics, you know, or straws, etc. So these are all kind of low hanging fruits that a lot of governments in rich countries in particular did because it was simple to do. It's an easy win, but policy makers across the globe have understood it's a systemic problem. It's a systems problem. You can't fix the symptoms by just improving recycling rates. So what I would hope for in a treaty is like systemic solutions that look at upstream the plastic life cycle, reducing the production of new plastics, thereby increasing the value of reusing plastics, increasing the value of like, you know, dealing in a smarter way with these valuable materials that would certainly regulate single-use plastics that really are very much likely to end up in nature, for instance, that would regulate chemicals of concern. We talked about it in plastics to better protect human health, but then would also have a strong component on the downstream side, you know. We know that a lot of plastics in the environment comes from mismanaged waste. So of course, we need to have better technology to manage all the waste, the plastic waste that we are creating. So I would hope for like systemic solution. And there is indications in the plastics treaty that there are those systemic solutions and components of it there, but it's strongly debated by countries, as you may know, that have strong interest in keeping the fossil fuel running. So there's a handful of spoilers, as they're now called, or Officially, the "like-minded countries" that would just like not have it at all, and they are framing the narrative in a way that's just a waste problem, so we just need to recycle a bit better, and then the problem will go away. Which all scientific evidence?
Marty Martin 54:36
Which countries or other jurisdictions right now have the sort of best policies, best approaches to emulate?
Martin Wagner 54:42
Well, it's a patchwork, and that's also why industry is actually quite in favor of having a global framework to deal with the plastics problem, because it's very patchy. The European Union, of course, is very pro-environment and very, very protective for for its citizens. So I guess, like chemical-wise, there's a strong framework in place in Europe that protects us from the most harmful chemicals. Korea, for instance, does the same. There have been bans of microbeads in cosmetics in, I think, more than 50 countries now. There have been bans on shopping bags in more than a hundred countries, if I recall correctly. So you have that patchwork of policies, but all of many of them are really kind of low hanging fruits, as I said before. And I think like the big solution, or the big vision of a solution, is what's called circular economy, right? So where, like plastic materials are somehow kept in a circle and being reused and repaired and repurposed, etc, thereby preventing all the waste generation, and that's like the big kind of vision that many policy makers, many governments have. I'm I still need to see its manifestations, but, but at least it's a vision.
Cameron Ghalambor 55:52
So Martin, I want to ask you about your sort of role in this process, because I think many scientists aspire to have their research matter in some way. If you're maybe an ecologist, you think about biodiversity. Obviously, doing toxicology work your research has direct implications for, you know, human health and the environment. But most, most scientists are, are really far removed from sort of having a seat at the table when these kinds of decisions about policy are made. Can you talk a little bit about what your role has been in this process and what kinds of like responsibilities you have? Are you sort of available as, like, expert witness? Or are you commissioned, you know, to provide, like, summary reports? Or what, what role do you have, or have had in this, in this process, in the past, or, like, moving forward?
Martin Wagner 56:58
Yeah, I think, like, I mean, my, my kind of attitude towards the role of science in policy making or in bigger societal discourses has changed over the time, right? I was kind of socialized in Germany, where there's a very strong notion and, you know, that scientists are neutral providers of evidence, so you just provide results, and then you just put it somewhere, and somebody else has to make sense of it or deal with it. And, you know, draw actions or recommendations from it. But, you know, I think, like the plastics discussions and plastic science has been kind of very much affected by the climate debate, of course, where we've seen, like, a lot of debates on what is the actual role of science in these kind of large environmental crisis that we're facing. And I've come to realize, while also having a tenured position, of course, that that is my responsibility to not just be a neutral provider of knowledge and educator, but also like, make sure that, like, the science that we're doing is put into action. So what we've done for the plastic treaty negotiations for the global plastic treaty is we've created a coalition of independent scientists. We have more than 400 scientists from more than 60 countries now, from all kinds of disciplines, all studying plastic and plastic pollution, trying to help negotiations to come at what we call arrive at an efficient plastic treaty that protects human health and the environment. So we're kind of still providing evidence and the best available evidence, but we're also having a political agenda, so we're not kind of coming in as neutral scientists there. But of course, we do want to protect, we do want to protect the environment, and we do want to end plastic pollution, and that's a political statement.
Martin Wagner 58:44
And that work has been incredible, first of all, because it's such an incredible experience to work with 400 people from across the globe, all experts, not easy, sometimes. Scientists, many scientists in the room, but we're sharing a common goal. So what we're basically doing is we're producing a lot of like evidence synthesis for policy makers to understand, and that's basically simplifying all the science that's out there, right? So there's about, I don't know, 15,000 papers on microplastics right now. So we are trying to kind of synthesize and simplify it for policy makers to understand about what are the problems and what are the solutions to that aspect of the problem of plastic pollution. We are going to these negotiations, and it's kind of a weird experience, if I can say, because it's diplomatic, it's a diplomatic affair, right? So it's diplomats meeting, it's very high-level. It's a lot of lobbyists. It's a lot of NGOs there, and then you have this bunch of scientists walking around the corridors with all the expertise in their brains. So it was kind of a steep learning curve. And how to, you know, talk to delegates, how to talk to diplomats who don't have a natural science background, often don't have a science background. Even, and, you know, really starting from scratch, explaining what plastics are, what chemicals are, what's the problem really? And that has been incredibly enriching. But what we're really trying to do is try to provide them with the evidence, answer the questions that they have, but also nudge them into systemic solutions. Because still, as I said, there's a strong push to just deal with the waste part of the problem, whereas the scientific evidence tells us we need to deal with the upstream part. We just make too much plastic, we put too many harmful chemicals in, etc. So that's basically what we're doing, and it's been a crazy ride, if I can say that.
Marty Martin 1:00:39
I can imagine there's, there's one group that you didn't, I think you didn't mention there, but last year, you wrote a commentary in nature about state and corporate interests, and you know how that's going to play out. What's your perspective on that? And what kinds of conversations have you had with the groups that are making plastics and have a very different agenda?
Martin Wagner 1:01:06
Yeah, so first of all, I would say plastics industry is often perceived as kind of this enigmatic black monolith, which is it is actually not. So there's quite a lot of companies that try to do the right thing. We have what is called the Business Coalition for an effective plastics treaty. So these are big multinationals that have come together to really fight for a strong plastics treaty. But those are usually not the makers of plastic. These are more like supermarket chains, brand owners, etc, that use and sell a lot of plastic. So they're sitting in the middle or at the end of the supply chain. Plastics industry has a sad history of defending their products against any concerns regarding human health or the environment, and we've seen it playing out for Bisphenol A. There was an epic decade long battle to keep Bisphenol A in plastic products, even though the best science told them it's harmful. It's harming our children, it's harming us, it's harming the environment. And what I'm arguing in that piece is that corporations should drop that product defense, should drop meddling with the science, because what they often do is they keep the appearance of the science isn't clear, that's called manufacturing doubt. We've seen that play out. It's actually a playbook that was developed by the tobacco industry, right and then it was translated to the climate crisis, and it's been translated to sugar in the diet, and it's been translated to chemicals and plastics as well. So basically, I'm arguing that those corporations should really kind of drop that manufacturing of doubt. They should stay out of the science they shouldn't like, try to meddle with the scientific evidence and cast out on science, and should stick with like what their core business is, namely, producing cheap, functioning, and safe plastics. So that's basically what I'm saying. And I got a lot of, let's say, critical feedback from people working for businesses.
Marty Martin 1:03:00
Yeah. Why is that not surprising?
Martin Wagner 1:03:04
It's not surprising, but I think it's something that needs to be said sometimes, because I think it's wasting everybody's money. It's also wasting the shareholders' money. If a company invests, like, hundreds of millions of dollars in PR keeping bad chemicals in plastic products, why can't they just invest that money to make better chemicals?
Marty Martin 1:03:22
Yeah, yeah. Another lesson to learn from the cycling of that tobacco paradigm is that oftentimes it eventually fails. So these are bad investments in a longer term for sure, yeah.
Cameron Ghalambor 1:03:32
Yeah. I just also wanted to, you know, bring up a success story in this regard, which is the Montreal Protocol, which eradicated ozone depleting substances. The hole in the ozone layer, you know, was found to be related to certain chemicals that were being produced, and this protocol eliminated those chemicals. And, you know that. I think from what I've read, the projections are that the ozone layer may recover by the year 2066, it's still, you know, there are still problems, but, but I think you know, for people who are pessimistic or or cynical about about change and the capacity for all of these diverse interests to get together and and work with each other for positive change, like it can happen, and we've seen it happen in the past, and so it, it hopefully will also be able to happen again in the future.
Cameron Ghalambor 1:04:41
And so I guess with that, maybe my one of my last questions to you would be for the general public, for our listeners in general. What advice do you give in terms of, like, how to avoid exposure? How to live in a plasticized world that we are in a responsible way? Both in terms of protecting yourself, but obviously, I'm assuming, you know, recycling and not throwing trash out. You know, these obvious things are there? Are there other bits of advice that you would give Sure?
Martin Wagner 1:05:15
I mean, it's great that you mentioned the Montreal Protocol, right? Because it's kind of the holy grail of multilateralism, environmental multilateralism, because it was so successful. And there was, like, key learnings from from Montreal Protocol. And one of all I want to throw out there, given the current political situation, it was actually Jimmy Carter who really put a lot of political will behind that treaty. And he really made it happen, and that, I think, gives us hope, or gives me hope, at least, that if there's leaders who champion environmental issues, they can even end up with a global treaty that's preventing, preventing crises. So there's hope there, if there's enough political will, the conversation we had was a bit doom and gloom, and that's like the nature of being a toxicologist. You know, we're kind of a bit perverse in the sense that we love all kinds of toxic and I'm sorry for that. It shouldn't sound like it shouldn't dishearten the listeners, really. Because I think there's many things you can do on a personal level, but also on a larger level, right? There's simple kind of tips how you can reduce your exposure to nano microplastics and to chemical and plastics if you're able to, you know, buy, buying unpacked fresh fruit, unprocessed food, etc. If you're kind of avoiding synthetic clothing, but use natural clothes, etc, if you people don't like it. But if you wet wipe your house all the time, you remove all the micro plastics in the dust, including all the chemicals, so do your cleaning properly. You know, wait,
Cameron Ghalambor 1:06:47
Can you expand on that? What do you what does that mean? Exactly like just having a wet towel and fabric and just wiping things down,
Martin Wagner 1:06:57
Right, so instead of hoovering, which basically just like worlds around, like all the dust that you inhale again, just like wipe it. It just wet wipe to remove, like, all the plastic particles and the dust which accumulates a lot of harmful chemicals. But I think, like, you know, we do know that human exposures mostly come from food and from inhalation, so kind of controlling, like the plastic and chemicals we are inhaling and eating by, you know, buying fresh produce, etc, if you're able to, I think these are all measures. Protecting kids is incredibly important, right? So you need to make sure that, like, the toys that you're giving your kids, etc, don't contain harmful chemicals. I would always argue that, like your purchase power is quite limited in the capitalistic system. Right, so we always are tricked to believe we just need to make the right choices when we buy something, and that will change the whole system. I don't believe in that. It's a mirage, honestly. But, you know, calling companies and asking them which chemicals are actually in that plastic toy that I'm going to purchase, I think that's actually that can make an impact. And then, of course, last of all, and I think, I do think we have a lot of scientists listening to this podcast. I think like scientists kind of making their science count in the policy sphere is incredibly, an incredibly valuable experience and incredibly powerful. My experience from the treaty is policy makers love to listen to scientists. They really want to get the evidence right. And I know these days we are often kind of a bit, you know, disillusioned about politics, can I say? But the policymakers I met, they really want to listen to the evidence, and they're really keen on hearing it from the experts. So going out there, talking to them, not only about plastics or pollution, about other things that really matter in, you know, the triple planetary crisis that we're facing, I think really can make a difference.
Marty Martin 1:08:52
Excellent. Well, that was definitely ending on a high note, at least in terms of having some ability to affect change. The last thing that we like to do, Martin, and we really appreciate your time, is sort of give you some space to hit any topic that we didn't prompt you. Is there anything else that you'd like to say?
Martin Wagner 1:09:08
Well, there's so much more micro plastics and chemicals, etc, but and politics as well, you know, but, yeah it's okay, I think.
Marty Martin 1:09:19
Yeah, okay, okay, well, good. Well, really, thank you so much. This was a lot of fun.
Cameron Ghalambor 1:09:24
Thanks so much. All right, this was really good.
Martin Wagner 1:09:27
Thank you so much for having me.
Cameron Ghalambor 1:09:52
Thanks for listening to this episode. If you like what you hear, let us know via Twitter, Bluesky, Facebook, Instagram. Or leave a review wherever you get your podcast, and if you don't like what you hear, well, we'd love to know that too. All feedback is good feedback.
Marty Martin 1:10:07
Thank you to Steve Lane, who manages the website, and Molly Magid for producing the episode.
Cameron Ghalambor 1:10:11
Thanks also to interns, Dayna de la Cruz, Caroline Merriman, and Brady Quinn for helping with this episode. Keating Shahmehri produces our awesome cover art.
Marty Martin 1:10:20
Thank you to the College of Public Health at the University of South Florida, the National Science Foundation and our Patreon and Substack subscribers for their support.
Cameron Ghalambor 1:10:28
Music on the episode is from Podington Bear and Tieren Costello.