0:04

So one topic that there's often a lot

0:06

of breathless reporting around Norman is microplastics. We

0:08

love to hate tiny bits of plastic. Just

0:10

in the last couple of weeks, I've

0:13

seen research on how much plastic is in

0:15

tap water, but then there was another

0:17

study that there was saying that there's a lot of plastic

0:19

in bottled water. So I guess you should just open

0:22

up your mouth outside when it rains. But then

0:24

there was another piece of research from

0:26

the UTS saying that there's nanoplastic in

0:28

the air that we inhale. So

0:31

it's basically unavoidable. And

0:33

then a year or two ago, I think I

0:35

did a story on microplastics in shellfish. And

0:37

at the time that I reported that, I was really

0:40

looking around for someone to kind of give me a

0:42

straight answer on what microplastics actually do in the body

0:44

because it sort of implied that they're bad. But

0:47

I didn't really know if there was a lot of evidence about it.

0:49

The evidence is becoming a bit more obvious,

0:51

especially when it comes to the tiniest of

0:54

plastics. So not microplastics, but

0:56

nanoplastics. The ones that are around a hundredth

0:58

of a width of a human hair, really,

1:00

really tiny particles. There's been

1:02

some very fundamental but important research

1:05

that's shown that nanoplastics may have

1:07

a role in cancer. And

1:10

the person who led that study was Lucas

1:12

Kenner from the University of Vienna. And

1:14

what we found was that these particles

1:16

stay in cancer cells, and

1:18

they even stay in the cancer cells

1:20

after cell division, which is very

1:23

interesting because normally cancer cells,

1:25

they don't keep anything, what

1:28

keeps them from growing. So our

1:30

suspicion was that if cancer cells

1:32

keep plastic particles, then they would

1:34

take advantage of them. So

1:37

that's Lucas Kenner from the University of Vienna. I

1:39

mean, it's interesting, Tegan. I

1:42

just have a healthy skepticism, not that I think

1:44

that nanoplastics are a great thing to have in

1:46

the environment, but what happens

1:48

in the laboratory is not necessarily what

1:50

happens in whole humans. No, exactly. But

1:53

I think that the thing that's interesting about this

1:55

research was that it was able to control for

1:57

a lot of things that other studies that have

1:59

impacted. had similar things haven't been able

2:01

to. So what they did was

2:03

they controlled for the shape of the plastic. They used

2:06

smooth round balls so that they could say,

2:09

okay, it wasn't physical damage from say a

2:11

jagged edge of a piece of nanoplastics and

2:13

they were pristine. So they didn't have

2:15

chemicals alongside them because we know that

2:18

plastic waste is often found alongside chemicals

2:20

that we know are harmful. So

2:22

that is cells in a dish, super

2:25

fundamental. The kind of research we need

2:27

to build a case against nanoplastics, but

2:29

in its early phases. So

2:31

for context, I've been speaking to Dr.

2:33

Cassie Rout from the University of Queensland,

2:35

who focuses really on the effect of

2:37

plastic on human health. At

2:40

the moment, the issue is we know very

2:42

little. So there are some studies

2:44

that are coming out that are really starting to, I

2:46

guess, get to the tip of the iceberg of what

2:48

we need to know. But this

2:50

study was probably one of the first

2:52

ones that I've seen that's actually looked

2:54

at cancer cell lines. And so what

2:56

they've done is they've exposed some

2:59

cancer cells to microplastics or nanoplastics and

3:01

then had a look at what happens

3:03

after that. But this is one of

3:06

the first areas of research that's looking

3:08

into this. So definitely it's only just

3:10

the beginning and we still have so many questions

3:12

that we need to understand so that we can

3:14

look at actual health effects. It's

3:16

kind of taken as a given, I think, in

3:19

the community that plastic's not good. And the fact

3:21

that it takes such a long time to break

3:23

down is not good. So why

3:25

has it been so hard to

3:28

quantify the harm, if any, of

3:30

plastic on our health? Well, it's more to

3:32

do with the size of the plastic that will have a

3:35

harm on our health. So we know

3:37

it's the very, very small sizes. So

3:39

what we term as nanosized plastic, they're

3:41

the ones that have the potential to,

3:43

what we say, cross biological barriers in

3:45

the body. So for instance, that can

3:47

get from inside our stomachs and our

3:50

test times into our bloodstream. So we

3:52

say across the gut blood barrier and

3:54

those sorts of things. But the problem

3:56

with these really, really small plastics is

3:58

they're very hard to determine. very

4:00

hard to analyze and to get data that's

4:03

really reliable. It takes a long time to

4:05

develop methods to be able to actually find

4:07

these small plastics. So we

4:09

know plastics are everywhere in the environment, and

4:11

we definitely know we're being exposed to them.

4:14

But in terms of finding this very, very

4:17

small size plastic that we're being exposed to

4:19

and what happens after exposure, it's a really

4:21

difficult question to answer. And that's why it's

4:23

taking scientists all over the world, and it's

4:25

a lot of research effort to try and

4:28

get down and to work out what's going

4:30

on here. Because plastics don't just

4:32

occur by themselves either. If an area

4:34

is contaminated with nanoplastics or microplastics, there

4:36

often will be other chemicals present as

4:39

well, if they're sites that

4:41

have been contaminated by, say, industry

4:43

or waste. Oh, definitely. So plastics,

4:45

there's, I guess, two areas that's

4:47

in terms of chemicals associated

4:49

with plastics. So plastics have chemicals

4:51

inside them. They're added to the

4:53

plastics to give the plastic a

4:55

certain property. So for plastics that

4:58

are quite bendy, they'll have chemicals

5:00

called phthalates or plasticizers in them. We

5:02

know that those chemicals really easily leach out,

5:04

and we can analyse those in the body.

5:06

So we do know we find those in

5:08

the body. But plastics also act as a

5:10

carrier for other chemicals. So like you were

5:12

saying, for instance, in industrial areas, where we

5:14

have lots of other chemicals that are in

5:16

use and might be in the same area

5:18

as the plastic, then those chemicals

5:21

actually get attached to the plastic. And

5:23

that's another way those plastics can carry

5:25

those chemicals around and then expose us

5:27

and the environment to those chemicals. So

5:30

for example, like PFAS chemicals. Yeah,

5:33

yep. So it's been quite well documented

5:35

that, for instance, PFAS very

5:38

nicely happily sit on polyethylene

5:40

type plastics. And so

5:42

that's one of the ways that they

5:44

can travel through, well, PFAS also in

5:46

water, but it helps them travel to

5:48

the Arctic and the Antarctic through waterways

5:50

carried on these plastics. So

5:53

looking at the potential health

5:55

harms of microplastics and nanoplastics

5:58

in and of themselves, how... How

6:00

has the field progressed over the last few

6:02

years? We know a lot more about

6:04

what we don't know, which

6:08

is a terrible answer, I'm sorry. So when we

6:10

first started looking at it five or ten years ago,

6:12

everyone thought it was going to be quite an

6:14

easy area to research. We're going

6:16

to find plastics everywhere. We're going to be

6:18

able to work out what's going on. We'd

6:20

have regulations in place by now. But

6:23

it's taken so long because the actual

6:25

research, as we go along, we found

6:27

that they don't necessarily behave as we

6:29

originally thought they would behave. We

6:32

have a lot of trouble with analysing

6:34

them. So there are a

6:36

lot of compounds that can actually interfere with

6:38

the analysis and then trying to develop methods

6:40

to remove those so that we can be

6:43

really sure and really accurate about what we're

6:45

reporting in terms of where these plastics end

6:47

up in the body or in the environment

6:49

has been really challenging. So the more that

6:51

we get into this field, the more challenges

6:53

that we've seen with analysis of these. There's

6:57

such a unique chemical pollutant, micro

6:59

nanoplastics, that a lot of us

7:01

that come from, say, organic chemical

7:04

backgrounds have all new issues that we

7:06

now need to learn to do with their

7:08

physical chemical properties because we're not just talking

7:10

about a chemical that's in the air and

7:12

the water. We're actually talking about a physical

7:15

particle and where that physical particle moves, how

7:17

it also degrades. We're

7:19

also talking about things like it can

7:22

form a corona, which is bits of

7:24

organic, which approach the plastic and

7:26

the plastic then behaves completely differently once that

7:28

has happened as well. So as we

7:31

progress with the science, we find

7:33

even more challenges and even more different ways

7:35

that these plastics behave and interact that we

7:38

now need to understand before we can work

7:40

out how that impacts us

7:42

after we are exposed. You

7:44

do hear reports that sort of filter

7:46

through into the media from research that

7:49

there's a bazillion pieces of nanoplastic

7:51

in a bottle of water or

7:54

it's in seafood. It feels

7:57

like the way that message is received by the public

7:59

is that it's inherently bad but what you're

8:01

saying is we don't actually know? Definitely

8:03

we don't want to be exposed to these plastics.

8:05

What we don't understand is what

8:07

other health effects from this

8:09

exposure. At the moment we're still

8:12

at the very forefront of the research trying

8:14

to understand what exactly and how much we

8:16

are exposed to and then the second step

8:18

of that is what are

8:20

the effects, what's the consequence of

8:22

this exposure. So unfortunately we're

8:24

just at the very early stages of

8:26

this really important scientific question and we

8:28

just don't have the information yet to

8:30

be able to say to everyone this

8:32

is a bad thing and to

8:35

be able to really put it into context

8:37

to give to everyone of

8:39

what the health outcomes are. It

8:42

is a tricky one because what you

8:44

want to be able to say neatly at the

8:46

end of this conversation is something like here are

8:48

some tips to reduce your plastics exposure but the

8:51

truth is that they're everywhere and they're

8:53

in places that are unexpected and really

8:55

it's a global and environmental intervention that

8:57

we need if we're actually going to

8:59

reduce our exposure. Yeah

9:02

definitely and we need to get governments on

9:04

board as well helping with putting policy in

9:06

place for reducing the amount of plastics that

9:08

we're using which then reduces the amount that's

9:10

going into the environment but small

9:12

things that we can do definitely do make a

9:14

difference so trying not to use

9:17

cheap plastic food containers we've shown that lots

9:19

of particles wash off of those every time

9:21

you use them so then that's plastic that's

9:23

getting into your food. You know

9:25

try and use a reusable water bottle instead

9:28

of single-use plastic water bottles all

9:30

those things can really reduce the amount of

9:32

plastic that you're actually ingesting. The

9:34

two main ways that we're exposed to plastics

9:37

is through what we're eating and then also through the

9:39

air we're breathing in as well. So

9:41

trying to reduce the amount of

9:43

synthetic clothing that you're wearing so

9:45

that's clothing that's listed as polyester

9:47

or nylon. Trying to use

9:49

natural fibers instead will also help to really

9:52

reduce the amount of plastics that you're breathing

9:54

in around you it's just small fibers coming

9:56

off that clothing so small things we

9:58

can do but as you said it is. everywhere

10:00

in the environment and it is

10:05

a big societal change to try and reduce

10:07

and try and reverse the problem that we

10:09

have got with the amount of plastic that

10:11

is currently in the environment and that is

10:14

also entering the environment constantly as well.

10:16

Well Cassie thank you so much. Alright thank you for having

10:19

me. So that's Dr Cassie

10:21

Raut who is a senior research fellow

10:23

at the Queensland Alliance for Environmental Health

10:25

Sciences at UQ. Stream

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