Have you washed a fleece jacket this week? Does your face wash or body wash have skin-smoothing microbeads? If you’ve answered “yes,” you might want to consider where those fleece fibers and microbeads end up.
Likely you already know marine debris is an issue in our oceans. You’ve heard of the “Great Pacific Garbage Patch,” and you may have recently read about the “North Atlantic Garbage Patch,” but what about marine plastics right here in the Gulf of Maine? And what are “microplastics?”
The only difference between marine plastic and marine microplastic is that microplastics are smaller. Much smaller. Smaller than the width of a typical pencil eraser. Some microplastics start out this small; others come from larger pieces being weathered or worn down. The tiniest of pieces, the nanoplastics, are even smaller still, less than half the width of a strand of your hair.
As you can imagine, these are hard to find in the ocean, but they’re there, and researchers, such as Dr. Steve Sutton at the University of New England (UNE) in Biddeford, are looking for them. “They’re extremely difficult to quantify,” said Sutton, so much research focuses on microplastics.
Researchers at the Marine Environmental Research Institute (MERI) in Blue Hill have been collecting samples to look at microplastics in Maine coastal waters since 2012. Last year they collected 4,935 pieces of microplastics from Penobscot and Blue Hill bays, averaging 14 pieces per liter of seawater.
MERI is not alone in seeking to better understand the distribution of microplastics in Maine. Dr. Neal Pettigrew from University of Maine is currently analyzing samples collected in Penobscot Bay for microplastics, and students at Maine Maritime Academy have sampled waters in Castine Harbor as well as in the Gulf of Maine in ocean science courses and senior research projects.
So what’s the big deal? Why do we—you, me, scientists—care how many microplastics are in the ocean or how big they are? First: animals eat microplastics. Microplastics are so small, even the tiniest of animals ingest them.
Stephanie Wright, a PhD candidate at the University of Exeter, was in the Gulf of Maine aboard The Rozalia Project’s American Promise during summer 2013 collecting samples for microplastics analysis. She recently published a scientific paper documenting their negative health effects on organisms at the bottom of the food chain.
“A diet containing microplastics causes marine worms to lose energy stores, which are essential for survival, growth and reproduction,” Wright said. Others report similar findings: organisms that eat plastic may feel full, but they aren’t getting essential nutrients. And microplastics can become tangled in their stomachs, blocking normal digestion.
Not only do tiny organisms eat microplastics, animals we eat, eat microplastics. Part of the problem is that chemicals stick to microplastics. If a commercially fished species eats microplastics (or eats a smaller critter that did) and these microplastics have harmful chemicals sticking to them, we might be eating these chemicals too. Do we know this is happening? No. Might it be? Yes, and a lot of scientists are focused on answering this exact question. If it is happening, scientists need to determine if it’s dangerous. The levels we’re talking about might not be a problem, or chemicals stuck to microplastics might pass through animals if the microplastics do. Easy come, easy go. Or not. We just don’t know.
MERI has begun looking at microplastics in commercially important species, collecting lobsters, mackerel, oysters, mussels and clams to see if these organisms eat microplastics and if they are causing chemical contamination. UNE is also working the contamination angle and aims to identify and measure the organic pollutants sticking to microplastics.
Where are these tiny plastics coming from? Some may come from fishing and boat lines, from buoys and marine litter, while others enter the ocean through waste water treatment centers, a result of residents washing fleece clothing and using face and body washes with plastic exfoliating microbeads. MERI recently refocused its sampling efforts to hone in on potential sources in Penobscot and Blue Hill bays.
Can we stop these microplastics from entering the ocean? We can try. Abby Barrows, a researcher at MERI, suggests, “Spearhead a plastic bag or single-use plastic ban in your town. Buy less synthetic clothing. Avoid personal products, such as cleansers or toothpaste, that contain microbeads.”
These are steps we can take now to reduce the flow of microplastics into Maine waters, and as we learn more, we’ll be able to take more direct action to reduce the impact.
Stacy R. Knapp is a PhD. candidate at the University of Maine in Orono and an adjunct faculty instructor at Maine Maritime Academy in Castine.