Hey, it's Science Friday, Producer Kathleen Davis, and you're listening to Sc...
Microplastics and nanoplastics have been in the news a lot. These are teeny, tiny pieces of plastic fragments that are found pretty much everywhere. They've been found in the soil, in the water, in our bodies, even on the top of Mount Everest. And it all feels overwhelming and existential.
But there's some good news too, just this week, the EPA announced it's taking the first step
to regulate microplastics in drinking water. And lots of scientists are looking for solutions for our microplastic malaise. And here to fill us in on some research happening in the Midwest is Kate Grumpke, Senior Environmental Reporter for St. Louis Public Radio. Hey, Kate, thanks for being here.
Hi, Kathleen. Thanks for having me.
“So Kate, as an environmental reporter, what's your level of personal concern?”
Or not microplastics? Like, where do they rank on your list of topics that are big and scary that you cover? Oh, man.
Well, we have a lot of scary weather events here.
So I would say that those can be maybe bigger or more urgent feeling than microplastics. But the thing about microplastics is you can end up thinking about them quite a lot because there's so much plastic in our daily life. So I feel like I have just constant reminders of this issue because there's so much plastic around us.
Right. So as I said, microplastics are everywhere. Has there been anything in your neck of the woods that has made you be like, okay, this is actually very freaky. Oh, definitely.
“So one story I wrote about was about a group of scientists at St. Louis University.”
They recently found microplastics in a cave around here that had been close to the public for 30 years. So there's a population of endangered bats in this cave. So people are generally not allowed to go in there and they found a lot of microplastics. And they found it in both the water and in sediment in the cave and one thing that was
really interesting, they published a paper about this that they found it even more during flooding. So the caves around St. Louis are generally kind of connected to the outside world and so during flooding events more of that outside world and the plastic inside of it is being washed into that cave.
Okay, so let's talk about a story that you did recently. You reported on a lab in Missouri that's doing some pretty innovative stuff with algae. Tell me about this. Yeah, so there is a professor at the University of Missouri who is working with engineered algae and she recently worked with a team to see what this would do with microplastics.
So this algae is essentially really hydrophobic, so it repels water and microplastics are also hydrophobic.
So they basically found that these algae sort of clump onto the microplastics and then
bring them down to the bottom of water and they're really good at cleaning the microplastics out of the water. So they laid out this process in a new paper in nature communications where they can kind of clean up the microplastics this way and then maybe even recycle that sludge of algae and microplastics into a new product.
Okay, so you said it's effective. How effective is it? They found that it removed more than 90% of microplastics in the water that they were testing in a solution. So very very good and it's especially good at removing super, super tiny pieces of plastic.
So sometimes it's easier to filter things that are bigger out but they are really targeting those super extra small pieces of plastic with this process. And we'll talk to the lead researcher on that study in a little bit here. But let's talk a little bit about other local efforts that you've reported on to tackle this microplastics problem.
Does anything spring to mind? Yeah, there have been a few other projects in St. Louis that are really interesting. One, I was especially interested in at St. Louis University. So there's a researcher there who is looking at creating something that kind of acts like whale boolean.
So this is the sort of like fibrous, not teeth, but teeth like structure in a whale's mouth. And so this professor realized that plankton are kind of a similar size to microplastics. And if whales are really good at sucking up plankton, maybe they could also use boolean to suck up microplastics. So I thought that was a really interesting test case.
And then at Washington University, they actually have a research center now that's working on creating plastic alternatives that are also kind of brewed and a natural process.
“So I think that that is pretty interesting as well.”
They're targeting fibers, which is a big problem from our clothes, from plastic in the clothing. And so yeah, there's a lot of people around here who are trying to find a solution to this
Problem.
I mean, as a reporter who covers this, how does it make you feel to have some kind of promising
“things to talk about when it comes to microplastics?”
This is one of those issues where I talked to the scientists and they're really hopeful. They're really excited about what they're working on. They feel like they're finding solutions to a big problem in our lives. So I really think that this is a great area to look at if you're looking for some hope in an otherwise kind of stressful environment.
Well, thanks so much Kate. Thanks Kathleen. Kate Grumpy senior environmental reporter for St. Louis Public Radio. We have to take a break, but don't go away.
When we come back, talking to the researcher behind this algae breakthrough, stay with us.
Now, we're going to dive into some more detail on this bioengineered algae. We've learned that it can clump onto microplastics and make them easier to remove, but how could it actually work out in the world? Joining me now is Dr. Susie Day, Professor of Chemical and Biological Engineering at the University of Missouri.
Thanks so much for being here. Oh, it's my great pleasure. So this isn't really exciting idea, right?
“And I know that you've gotten a lot of attention for this, but is it scalable?”
Like, how can we imagine this actually working effectively in the future?
Yeah, and it's more than one million dollars question, right?
So we have to remember what dealing with multiple things here. Number one, we need to grow a stable culture in the container that's large enough for treatment of our target of the water. And number two, and this is really a genetic modified organism. And many times, people are concerned about those genetic modified organisms.
Then in my vision, we are not to really release that back into the environment. So this will be done in a confined environment. So once you design a bio-reactor, you can have this algebra in a controlled manner, such as you can control the temperature, you can control the pH, you can control many things. So in this case, then now we can cultivate at the optimized condition in the future,
in large containers that we can put in the field, potentially, in the plant or in the facility. That's supposed to be used together for other water treatment purposes. So we're talking about keeping this in like wastewater plants. Yes, and so with the water plant is a viable venue to operate with this. But together, we can think of if you have other water body that the algae can grow.
So that we can also use those water bodies, potentially, with other source of contamination. And then we can also integrate this reactor for other purposes. Because algae can use CO2 carbon dioxide as its carbon source.
So basically, you can grow it in the place once you have sunlight, right?
And then you can grow it with water that coming with extra of the nutrient that you want to remove. So definitely with water plant is one that's the nation that we can implement this platform. But the other places may be in the culture that we can do that too. So microplastics are everywhere. I think this is something that most people are aware of at this point. I mean, in the grand scale of this issue, how impactful would it be to be able to get microplastics out of waste water?
Like, how much of a dent do you think that could make on this overall problem? Yeah, and that's actually a question, a multi-level analysis. So I think right now, people know what have the presence of those microplastics. And then we don't really know what's the final impact in our ecosystem in urban areas, right? I think we know better in the same and in those waters.
But how much do we know those microplastics are getting into our life, into our food system, into our ginger and system? So together with treatment of those microplastics,
“I think another benefit we need to remember is this algae can also remove the extra nutrient from the”
wastewater. Currently, most of the wastewater facility are designed to deal with the organic carbon and oxygen level. But most of the current infrastructure for wastewater treatment is not dealing with an extra nitrogen and a phosphorus. So that's what I hope this platform is not only bring one benefit, but one stone for multiple birds. Then when we can manage microplastics, which is a emerging contaminants, still with a lot of research needs going on,
we can also do at the same time remove those extra nutrients that are also not very good for our environment. Before I let you go, I want to ask you because I hear you did not necessarily originally
Intend to make an algae that could absorb microplastics.
Yes, that's a very good question. So I think this feels on years of the research
“when we're trying to work on algae in the very beginning and that time we didn't have this”
beautiful imagination. We can apply the algae for this purpose. At that time, we're looking into using algae as a fetus stock to produce high value products. So if you look at the structure,
the chemical property of this component coming from the algae. This is a wonderful component. You can
think of a parallel to all those evasion fuel you can pump into the prime. And this component has
“a high energy density than ethanol. Nowadays, everybody pump about 10% of our ethanol into our”
fuel tank for the car, right? And then because of energy intensity for this molecule is higher
than ethanol, it made that a more ideal for the evasion fuel. And that's the original purpose.
I mean, aviation fuel is so different from microplastics cleanup. How did you get from point to point B? In parallel to that study process, we're looking to other means to remove those contaminants from the water, such as using the fungus biomass to remove those microplastics. So because those two research lines are going on with each other in parallel, and when we saw that algae can self precipitate, then some eternally we're thinking, oh, what can we do is it?
So how about we'll apply that to the microplastics and then can we observe the same phenomena and bingo, it happens? I mean, this to me is such a perfect example of how random and unexpected
“scientific discovery can be sometimes. Yes, that's why I think as scientists, we should not limit”
ourselves for the owning go at that time for that one research project. I think very interesting about a research is you have open mind, then you talk with people, then you collaborate, and then a different ones come together, I think, create a much better project than the one by the self in the very beginning. Well, thank you so much, Susie. This was such a great conversation. I really appreciate the chance to talk to you about this. Yeah, thank you for your time and
my great pleasure talking to you. Dr. Susie Day is a professor of chemical and biological engineering at the University of Missouri. This episode was produced by me Kathleen Davis, and if there's another good news story about a big environmental problem that you want us to talk about, give us a ring, 877-4 Cyfry. That's 877-4 Cyfry. We'll catch you next time. I'm Kathleen Davis. [BLANK_AUDIO]

