UC Science Radio: Season 2 Episode 3 transcript

Helena Ruffell: The dirt on plastic

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Molly Magid: Welcome to UC Science Radio, where we interview a range of postgrad students to tune into the fresh voices entering the world of science and learn what sparked their passion. I’m Molly Magid, a Master’s student in the School of Biological Sciences.

Today I’m talking with Helena Ruffell, she’s a PhD student studying Environmental Science at UC. Her research focuses on environmental contamination. She’s also passionate about finding ways to reduce her own waste and inspires others to do the same by sharing her ideas on Instagram.

Kia ora Helena, welcome to UC Science Radio.
Helena Ruffell:
Kia ora Molly. Thanks for having me on here.

I know you study environmental science, but what specifically is your research about?
I'm studying environmental science but I'm in the chemistry department at UC. My research is looking at if microplastics affect productive soil systems for my PhD. A productive soil system can be horticultural soils, agricultural soils. I'm also looking at compost, so if you think about in Christchurch how we have our green rubbish bins where we put all of our food scraps into, they're eventually made into compost. And also biosolids. That's what happens at the wastewater treatment plant when we flush everything down the sink, all of the solid parts are scraped to the side and then they're dried and applied onto land like a soil remediation.

I'm looking at microplastics, which are plastic particles smaller than 5 mm in size, and they're such a huge problem mainly because of their tiny size—such a small thing is such a huge problem. Microplastics have been shown to be taken up passively, or actively sought out by a range of aquatic and terrestrial organisms. This has a whole heap of issues for them because it can get stuck in their guts, where they think they're full and then they end up starving to death because they’re not getting the nutrients they need. Or the sharp sides of plastics could cause internal damage to their organs, as well as harbouring a range of nasty chemicals onto their surfaces, which when they are taken up by organisms, they can then leach out from the plastics and then transport all around their body systems and maybe have a whole range of effects including oxidative stress.

And also, as we all know, plastic is just a huge pollutant, which is quite obviously everywhere. You can see it, you know washing up on our beaches. It's hard to go for a walk anywhere, even to a park, even down the street, without coming across a piece of plastic. I'm focusing on the ones that we actually can't see. And the focus on productive soil systems, of course, is because they are really important for us. Microplastics might affect plants, it might affect their growth, or it might affect the community of microorganisms which are so, so important for soil health.

So these microplastics are getting into the sewage waste stream or compost, and then this material is getting onto the soil?
Yeah, if you think back to all of the plastic products we use in our life, there is so much. Everyone has a house full of plastic, right? The annoying thing about plastic is that it's such as ideal material because it's so durable but it will never go away. So, it's ideal for a range of products but that's the problem, it doesn't go away, it just breaks down into smaller and smaller pieces, into these microplastics.

What I was looking at for my master's, at UC as well, was the amount of microplastics which were being washed down the sink from our homes, from us, from our businesses and industries into the wastewater treatment plant. So that's everything we wash down the sink. All the wastewater treatment plants I looked at, they released their slightly cleaner water, which is called effluent, directly into the coastline. That's millions of microplastic particles going out to sea every day. A lot of the literature has said that wastewater treatment plants are about 99% efficient at removing microplastic particles, so if 99% of plastic particles are being removed, and then there's still millions going out to sea, which means there's an even greater number being held up in the sludge. That's just for the wastewater.

If you think about our compost, so you know those really annoying fruit stickers that come on apples and bananas? Everyone's just gonna to chuck them straight into the compost bin, right? Compostable bags and compostable products, it's really hard for consumers to actually know if something is compostable. Just because it says it on the side doesn't mean it actually is, because it might need a specialist facility with the right temperature, and water conditions, and so on, for it to actually break down. Our green bins in Christchurch, they don't have those conditions. They're just designed to compost our food scraps. They can't handle plastic. That's where the plastic contamination can't be properly dealt with and then it does end up being shredded up and made into bags of compost, which we use to put on our gardens to make our veggie gardens. It's also sold commercially to farmers and horticulture businesses. It's pretty crazy when you think back, it's all about what plastic we use in our homes and where we think it ends up.

Some of your work, not related to your research, but stuff that you do on Instagramis to show people how they can reduce their plastic use in their daily lives. How did you get into that?
I found that doing a project on microplastics, it was really hard to not do anything about it. You know, I’ve been reading so much literature about how plastic is bad and plastic is something that we all use. So I started off with realizing you could swap your toothbrush for a bamboo toothbrush or your plastic shampoo bottle for a solid shampoo bar. The more that I learned, I really wanted to share that as well, I felt responsible for sharing what I learned and helping other people out. And it has actually been really awesome because I've had a whole heap of friends come up to me and be like "oh I had no idea about this and I'm really keen to try this out and it was all from your Instagram.” And that’s just the best feeling in the world.

You're super passionate about this work, but how did you get interested in environmental science? What was your path to this?
At the time I started uni in 2014 for my BSc, environmental science wasn't really offered as a stand-alone course, it was more of an endorsement. Instead, I decided to go down the biochemistry route. I had a couple of lectures about toxicology. That was mainly about the personal care products and pharmaceuticals, and other chemicals like pesticides that we're exposed to through our facial creams and medication we take, even fruits and vegetables that have been sprayed with pesticides and herbicides, and actually understanding the effect that it has on our bodies. You know, how these chemicals can interfere with our natural receptors and how it wreaks havoc. That's where it started for me mainly, and I started trying to change to as many natural products as possible to avoid these nasty chemicals.

I just kind of decided then that’s what I really wanted to do, I wanted to focus on these environmental pollutants. Because how is it fair that we're allowing ourselves to be exposed to these nasty things which are causing horrible effects on us, whereas these big companies and corporations are just getting away with it because they're getting a huge profit. That is when I decided I wanted to do a Master's in environmental chemistry. I had a really brilliant lecturer Sally (Gaw) who really did spark my interest. She also had a lecture on microplastics—that’s just a huge, huge source of pollution in our lives, but the thing is it's one that we can actually avoid. With some pharmaceuticals and fertilizers we can't actually really avoid them because that might actually be the only fruit and veggies available at the time, or we have to be on that medication. But with plastic it is totally avoidable and there are other alternatives to that. It's just a common thing that we all share, we use so much plastic. That's when I decided I wanted to have a look at plastics and it just developed from there.

Just from searching through the literature, it was just kind of insane how the clothes I was wearing and everything I was tipping down the sink was ending up at the wastewater treatment plants. That's when we figured out a plan for my Master's, to investigate microplastics in wastewater in Christchurch. Then from doing my Master's, the more I read, the more, again, responsible I felt to continue on with studying this. Because microplastics in soil makes up about 5% of the total literature with microplastics, mostly it's focused in the marine environment and freshwater environment. So no one really knows a lot about (microplastics in) soil but then I think it's probably the most important because soil involves us. All of our food is grown on soil and, of course, we live on the land. So I just thought it was really important to continue.

What's the most fun or exciting part of your work?
Probably when I do my analysis, which actually also turns out being the hardest part. The way that I analyse my samples for microplastics is once I've managed to filter everything onto these tiny little filter papers, I then look under the microscope to see what I have, to see if I have any plastics at all. Which, you'd be surprised, just because you can't see something doesn't mean it's not there. Once you look at it through a microscope, generally there's heaps and heaps of plastic, which is kind of sad for the environment, but also kind of exciting for me to say "Oh yay I've managed to get something."

Once I've gotten a look at them under the microscope, then I pick them all out individually with tweezers, and we kind of joke that from doing postgrad you end up with a lot of different life skills, and mine’s probably the ability to be a brain surgeon now from having such a steady hand with trying to pick out tiny, tiny pieces of plastic about 100 micrometres, which is just so small, with tweezers. Then I put that onto a machine called an FTIR, so that's a Fourier-Transform Infrared Spectroscopy, if anyone is familiar with spectroscopy, which then fires a laser through the plastic and it comes up with a spectra which will tell us if it is plastic or if it isn't. It's really exciting because then I can see what I've found is actually plastic. Then it will tell me what type of plastic it is, so if it's polyester, polypropylene, or polyethylene. You know, again, it's sad for the environment that it is plastic, but it is kind of exciting to see that I've managed to find something, that actually works.

My last question is, I know that you're just starting your PhD, but that means it's the time to dream big, so if you could see one big application of your research out in the world, what would it be?
Oh it would just definitely be to reduce the amount of plastic that we use daily. Because, there's no point cleaning up the plastic after it's happened, we might as well turn it off at the source. Like, you know, instead of bucketing, cleaning up the water off the floor, you have to turn the tap off.

Thank you so much for talking with me, Helena. I really enjoyed our conversation.
Yeah same here, thanks Molly.

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