Liam Tank, a biology student, lies on his stomach next to the Boardman-Ottaway River. He dips a metal water bottle in and out of the water three times. Then, on the fourth dip underwater, he screws the cap closed.
Tank and his classmates will take the bottle back to their lab at Northwestern Michigan College and pour the water through a filter.
“After that, we look under a microscope and count out … how many pieces of plastic are there,” Tank explained.
NMC biology students are testing the Boardman-Ottaway River watershed for microplastics — tiny pieces of plastic smaller than five millimeters, or about the size of a pencil eraser.
They’re sampling 24 sites throughout the watershed, including small creeks and tributaries.
“I think we’ve found microplastics in all but one,” said Nick Roster, the NMC biology professor spearheading the project.
Roster says he’s not surprised by what his students are finding.
“There's a misunderstanding of the sheer amount of plastic in our watershed,” Roster said. “You look at the river, and you could watch us pour out a sample and it looks like beautiful crystal clear water. But it's not.”
Tiny specks and strands of purple, blue, and red plastic show up under the microscope back at the lab.
“It’s a bit of a reality check,” said Timothy Vang, who’s in the class and grew up in Traverse City. “[It’s] something all of us need to know, so maybe we can form efforts to fix it.”
Microplastics can come from bigger pieces of plastic, like bags and bottles that have broken down.
But they can also start small, like the little fibers that shed off our polyester clothes, or the tiny beads added to certain toothpastes and other beauty products we flush down the drain.
From there, they can break down even further into nanoplastics.
“While microplastics may not be able to get into your body, nanoplastics can,” said Roster. “We don't know of any direct health effects, but the possibility is there. And so … while it doesn't seem like that big of a deal, as these plastics continue to break down, they'll create more and more hazards for us.”
Microplastics are considered an “emerging contaminant,” and there’s still limited research on how nanoplastics accumulate in and affect the body. They’re small and hard to study, and we haven’t known about them for very long.
For similar reasons, there’s also a lack of research on the environmental risks they might pose, particularly in freshwater ecosystems.
Roster says he and his students will sample once a month over at least the next two years. The idea is to gather baseline data about where and how much microplastic is in the Boardman River watershed.
He says he hopes it will raise awareness about microplastic pollution in the region and spur government action to manage and prevent it.
So what to do about it? Using less single-use plastic like water bottles, straws, and plastic bags is a good first step to limiting microplastics.
But the solution has to stretch beyond that. Experts say we need to improve recycling processes and rethink how we design plastic products.
And more research is needed to understand how microplastics might affect our ecosystems and our bodies.
