Science Friday
Hosted by Flora Lichtman
Measuring microplastics can be hard, partly because they're everywhere—including the lab. One researcher is working on solutions.
1,738 words · 2 speakers
Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
Hey, it's Flora and you're listening to Science Friday. You have seen the headlines, like, "We've got a spoon's worth of plastic in our brains," and "Microplastics are found in our hearts and our lymph nodes and our bloodstream." It sounds alarming, but the story might be more complicated than it seems. It turns out that measuring microplastics is really hard to do because, guess what? We're surrounded by plastics, including the pipettes and Petri dishes and gloves that we use in the lab. Here to tell us more about this challenge and how she's working to get around it is Dr. Cassandra Rout, who studies microplastics exposure at the University of Queensland
in Australia. Cassie, welcome to Science Friday.
Thank you for having me. It's lovely to be here.
Okay, tell us about this problem. Why is microplastic measurement a challenge?
Okay, so there are a lot of challenges. The problems with the microplastics analysis is that the field is so young, in terms of the science, is so young. So really, we've only been looking at plastics in the environment for roughly the last 10 years, plastics in humans for the last four years. So we're very, very early in the technology and in the development to be able to detect them. And this is really where our research is focused, is on how to overcome these challenges. So one of the biggest challenges we have in the field is background contamination. You covered this really nicely in your introduction. There are plastics everywhere, and there are plastics everywhere in the chemistry lab.
But when we are surrounded in an environment that's full of plastic, these materials can shed particles and then they can get into the sample that you're analyzing. So it means we've done, when we've been processing the sample, what we've done is accidentally introduced plastic into it that wasn't there originally.
Right, so it makes the concentrations seem higher than they actually are.
Exactly. Yep. So what we did, the first thing we did is we actually built from scratch a plastic-free environment that we could process our samples. So we call this the Minderoo Clean Lab. Um, it's made completely out of stainless steel to try and avoid plastic in the paint, in the walls, plastic in the lino, in the flooring, um, plastic in the ceiling tiles. Um, there's plastics everywhere in construction materials. So we had to build this lab out of stainless steel.
What does it look like in there? I mean, is it very shiny? Like, what's the experience of being in an all stainless steel room?
We, um, we affectionately call it the submarine because it does feel like you're going to kind of undersea. There's no windows, so except for one window where you look in. Um, so it does feel like you're going into this weird enclosed space. But I like to think of it as more of like what you would imagine industrial kitchen looks like. So everything's stainless steel. We've got stainless steel shelves, we've got stainless steel fume cupboards, and then we've just got glassware sitting on the shelves. So I guess it can kind of look a little bit futuristic, definitely very shiny. Um, it is a big metal box, so it can get a bit noisy in there. So we have acoustic panels, which are made out of aluminium, again, metal. Um, but yeah, it's, it's a massive metal box.
Um, but kind of looks like an industrial kitchen, I suppose.
What about all the pipettes and petri dishes and beakers? What do you do about those?
Yeah, so we've been able to exchange everything into a glass or a stainless steel alternative. Um, so even boxes that we carry our samples in are stainless steel. We use glass syringes instead of plastic pipettes. Um, we've been able to exchange everything out. So there's never any plastic that actually touches the sample.
Wow, I mean, it really shows you how pervasive plastic is when you go through the list of things that, um, you've had to exchange out. I mean, did, did it change your results?
Absolutely. So when we first commissioned the lab, we did some background testing just to see what we could detect in there compared to our normal lab where we do all of our other research. Background concentrations were a hundred times lower in the clean lab. So it drastically reduces any potential for contamination. What's interesting is that we still can detect some trace levels sometimes. A lot of the plastics are probably what we're bringing into the room with us. So plastics in the air, they tend to be charged. We have like this particle bubble that surrounds us where we've got these static particles that just attach to our clothes. So we can actually bring them into the room with us. So we change into a
fresh lab coat, we put, we put, have pull up cotton pants that we put over our clothing before we enter the clean room to try and reduce this. But there's always some tiny particles that you still manage to bring in with you. So this just goes back to, as you said, they're so pervasive. It's just plastics everywhere. And that's why it, background contamination is one of the biggest challenges that we have.
Given, given this, how do we think about previous research on microplastics? Like especially microplastics in the human body?
Um, I, okay, I'm gonna take a second just to think. So, um, some of the previous studies have either not accounted for background contamination or just haven't reported it in their studies. And I think that's a limitation in some of the previous studies that have been published, that we don't know if they're just reporting, say, something falling out of the air rather than an actual plastic in the sample. But the other big problem when we're looking at what's in our bodies is that tissues and blood are very complex matrix to try and analyze. They're a very complex sample. You've got fats, you've got proteins,
you've got carbohydrates, you've got blood cells, you've got so many different components in this sample that you need to try and remove. Um. With our current analysis techniques that we have available to us, they're very limited in trying to distinguish a plastic particle from these other bits in the sample. So what our research has been showing is that, for instance, polyethylene will give you the same signal as, say, lipid or fat that's in the sample. So that's really where our research has been going to try and improve analysis techniques. But I do wanna reiterate the fact, this is a very new area of research
in terms of understanding uh what's inside our bodies. So we're still learning, we're still trying to improve the techniques and get the data better. So we have started a group called the Plastics Measurements Brains Trust, and we have about thirty uh global researchers, all different expertise, all different fields, but all working on the theme of plastics and human health. And we come together once a year and have big meeting and discuss how we can improve the field, how we can improve the data that's being, that's coming out. So we published a paper in January this year that really talked about how we can use different techniques together on the same sample to try and improve the confidence in the data. And this is really what we're advocating for in um future studies
that are trying to look at plastics inside humans. Um. So there are things happening in the field. Um. We're not there yet, it's not perfect, but I do think, give us another five or so years and we will start to see um improvements and more collaborations and people working together to improve the data that's coming out as well. And hopefully have a better handle on um if there's any um influence between plastics and human health.
This is so fascinating. I mean, it it's really cool to get a window into, also just to sort of see how a new field evolves. So thank you for that.
Yeah, this is the first time I've worked on a chemical of concern or an emerging chemical of concern right from the beginning. Uh. So it's been a learning curve for me as well.
Given this, how do you personally relate to your microplastic exposure risk?
I, in my everyday life, do put in measures to reduce the amount of plastics that I have in my home. So when I first started working in this field, actually, I changed all of my kitchen utensils. I just had cheap plastic kitchen utensils and plastic chopping boards. I just changed all of those out. Even if we don't have a good understanding on potential health implications from exposure to plastics, I still think it's a good idea to be cautious about them and reduce the amount of plastics that we're exposed to wherever you can. Plastics are not just a polymer. They're not just a physical thing. They actually also have a lot of chemicals. We call these plastic additive chemicals.
They're chemicals like phthalates or bisphenol A that people may have heard of. And these are endocrine disruptors. And we do have really good data on associations between exposure to these chemicals and negative health effects. So even if we don't understand potential health effects from plastics exposure, we do know that there's a lot of negative health effects from these chemicals like phthalates and bisphenols. So from that point of view, I think it's a good reason to be reducing your plastics exposure because you do then also reduce your exposure to these chemicals.
Dr. Cassandra Rout is a research fellow studying microplastics exposure at the University of Queensland in Australia. Thanks again.
Thank you.
This episode was produced by Rasha Aridi and Kathleen Davis. And if you'd like to increase your exposure to Science Friday, catch us tomorrow and the next day and the next day on the podcast and then tell your friends about it because they could probably use a teaspoon worth of Science Friday in their brains, right? I know I'm taking this very far. Okay, see you tomorrow. I'm Flora Lichtman.
Page updated October 30, 2026 · transcript and summary are machine-generated