[dramatic music] - [Evan] Georgia Busch takes littering on the beach personally.

- [Georgia] It's not my trash, but it's my planet.

- [Evan] And she wanted to get a better idea about where it was coming from, so she and her colleagues enlisted the help of local volunteers and launched what was called the Hurricane Florence Marine Debris Recovery Project in 2018.

- After about two years of collecting marine debris, we discovered that almost 80% of the marine debris was residential docks and piers.

- [Evan] She says the debris from those broken off sections was everywhere, on the beaches and in the water in and around Wilmington.

And most of it: Styrofoam, which was the main source of flotation for these kinds of structures.

- Polystyrene, which is the chemical form of Styrofoam, and that Styrofoam component in the docks and piers can easily break apart, eventually becoming microplastics.

[dramatic music continues] - [Evan] The thing about microplastics is that they don't just vanish away.

The average lifespan of any piece of plastic is about 500 years.

What's made out of plastic?

More than you might imagine.

There's the obvious: the milk jugs, grocery bags.

But you might not realize that most clothing has plastic in it as well.

And chewing gum, yes, chewing gum.

- Yes, yeah, yes.

[laughing] - [Evan] From Busch's standpoint, nothing is disposable.

And she sees it every day at work, every time beachgoers are on vacation.

- It's a Shibumi tag.

[laughing] That's harsh.

[laughing] [somber music] - [Evan] Project volunteers were given a kit like this one to take samples and handed a cheat sheet to find these microplastics, which was a grid with spaces five millimeters in size.

Busch said it was a labor of love.

- So what I'm doing here is trying to get all of the sand sieved through while what remains will be our little microplastics.

And here is an excellent example of a piece of polystyrene.

You can see it's squishy and light and fluffy, and it will fly away, but that's a great example of the exact microplastics that we're targeting.

[dramatic music] And there it goes.

- [Evan] And that's just what washed up on the beach.

If we go from the beach and through the Mason Inlet, we get to the salt marshes.

It's here where Busch says the microplastics can be carried in from the ocean tides and onward.

She says the problem is that microplastics can get so small, they can get into the food supply of the fish and wildlife, and ultimately, into the food we, ourselves, eat.

And at the end of the day, she says it's not just coming from the beach.

- We got ourselves another piece of plastic there.

[glass clinking] Yeah, the coast is the ultimate downriver depository for anything that happens inland.

So upriver, in our inland freshwater rivers and streams, that's another place where we can attack microplastics and plastic pollution in general.

[dramatic music] - [Barbara] Wow what do we have here today?

Look at this, Jack.

- [Evan] Cue Barbara Doll, who's looking for those microplastics in those inland rivers and streams and who's documenting how things go from big to small.

- We believe a lotta the microplastics on the river are actually coming from trash that's being washed off urban and kinda suburban areas, getting into the stream.

So why do we wanna know that?

Because if we care about the microplastics and we wanna prevent it, we need to know the source.

[dramatic music continues] Perfect.

[water sloshing] - [Evan] Theirs is the first ever study on microplastics in North Carolina rivers and waterways.

The report cover the Neuse River Basin, the geographic range starting in the heavily urban Triangle and 200 miles down along the Neuse River and out to the Pamlico Sound.

They found that an estimated 230 billion pieces of microplastics are in the river and waterways of the Neuse River Basin, which flow east toward the Atlantic every year.

[dramatic music continues] Doll said it was important to go straight to one of the upriver areas where they took samples.

We met her in North Raleigh under a small bridge over the Marsh Creek.

She says a lot of what they found was exactly what Georgia Busch was finding on the beach.

[dramatic music continues] - And the most common microplastics that we found were the polystyrene, the polyethylene, the polypropylene, and the PET, which is like your plastic bottles.

So those were some of the most common things.

Well, lo and behold, when we looked at the macroplastics, Styrofoam was the most common item that we found.

92% of all the litter we collected was plastic.

[dramatic music] - [Georgia] Oh, look at that.

- [Evan] Remember that survey from Wrightsville Beach in measuring the five-millimeter samples?

Doll and her team measure things in what are called microns, really small, so they can determine the scope of what's getting into the river.

- They're kind of just breaking down into smaller and smaller plastics.

They're not really becoming their base elements.

They're just getting smaller and smaller particles over time.

So we wanted to test, how does that concentration change as you consider smaller and smaller particles?

That opening for that mesh is about half the size of a mechanical pencil lead.

And then, we use a much smaller one here.

This is the 64-micron mesh, which is openings about the size of the average human hair.

So the diameter of a human hair.

[dramatic music continues] - [Evan] Again, smaller and smaller, but not to nothing.

Up next was South Raleigh along the Neuse River at Anderson Point Park.

It was here and nearby Crabtree Creek where they brought out more netting to collect the samples they need to create a snapshot of where microplastics are coming from.

- We have little fish.

[laughing] Marsh Creek flows into Crabtree Creek, which then goes into the Neuse River.

The Neuse River itself is about 200 miles long, but you have thousands of miles of smaller tributaries and even backyard streams that drain into the Neuse.

So there's a whole river basin and a whole network of waterways that go into the river.

- [Evan] Doll says we're looking for solutions in the wrong places, that while municipalities laid down rules on stormwater drainage to stop macroplastics from getting into the water in the first place, not enough attention is being paid to, shall we say, the little things, the microplastics we've already put in the environment.

- These municipalities that have these stormwater permits would also have to manage for trash, because it is a pollutant in our waterways and it breaks down into these tiny fragments that are gonna flow on down the river and contaminate our food and cause other environmental consequences.

[dramatic music continues] - [Evan] Busch and her colleagues were able to get the data they needed to prove to a local beach town to use capsulated or protected polystyrene for their docks and piers.

And with that success, she says she still has hope that local and state officials will take a closer look at this invisible danger.

- [Georgia] Thinking about the life of any consumer product that we have in our hands, can it turn into microplastics and end up in the ocean, or can I make a better choice to begin with and not use any plastics at all?

[dramatic music continues]