A recent study found the Apostle Islands National Lakeshore had the highest concentration of microplastics out of 35 national parks surveyed. A group of researchers this summer are trying to find out why.
"We’re looking for stuff that’s less than five millimeters," said Brenda Lafrancois while taking a sample of sand from Meyer’s Beach.
Lafrancois is an Aquatic Ecologist for the National Park Service, which is teaming up with researchers from the University of Minnesota Duluth to look into the abundance of microplastics in the Lakeshore, what type of plastics they are, and where they came from.
Meyer’s Beach is one of eight beaches within the Lakeshore being sampled. The researchers are also taking water samples and samples from outside the Lakeshore as a control.
The samples will be tested at UMD this fall.
"What we’re hoping to answer in the lab is what type of plastics are out there and where they might be coming from," said Liz Minor, Professor of Chemistry and Biochemistry at UMD and Large Lakes Observatory, "What they are and where they’re coming from helps us to determine how to prevent them from getting there [the Apostle Islands]."
The study this summer stems from one which began in 2015. When the National Park Service and Clemson University studied microplastics at 35 national parks across the country. It found that a site in the Apostle Islands had the highest concentration of microplastics out of all the sites surveyed.
Lafrancois was involved in that study.
"I know these parks pretty well. I’ve sat on those beaches and I didn’t expect to see those levels of plastics we saw [in relation to the other sites]," she said, "So, I started thinking about a broader study."
The broader study hopes to determine why the Apostle Islands had such a high concentration of microplastics in the 2015 study. The researchers say one possibility is currents could have brought the plastics to the lakeshore.
There’s also a possibility the 2015 study was misleading due to its small sample size. It’s possible the sample in that study could have been taken at a time when a current with a lot of microplastics came through.
Whatever they find, Lafrancois says microplastics are a man-made problem.
"All of these plastics that we’re looking at are man-made materials. So, whenever we see them in the environment, they came from a source that humans contributed to, so there are lots of things we can do on the prevention side."