Narragansett Bay is proof of how reliant people have become on plastic. Researchers at the University of Rhode Island estimate the top 2 inches of the floor of the bay contain more than 1,000 tons of microplastics, plastic pieces less than 5 millimeters in diameter.
“That has been accumulating over the past 10 to 20 years, and so plastics are coming into the bay, they float through the water and eventually they land on the seabed,” University of Rhode Island researcher Victoria Fulfer said. “And so over time they’re accumulating at these really high concentrations because we just keep using plastics and the sources are not being mitigated.”
Fulfer, who published the study in 2023 with J.P. Walsh, the director of URI’s Coastal Resources Center, described the levels as “shocking.”
Using a towed sled, they documented how much debris lies in the water. They found that the upper parts of the bay, near Providence, contain higher concentrations of plastic waste than the lower bay.
“Plastics come from people, and in Rhode Island we have a really dense population particularly surrounding the Northern Bay … which just means inherently there’s going to be more plastic in that area that can make its way into the Bay,” Fulfer said.
And before they end up at the bottom of the bay, many are littered throughout Rhode Island’s beaches, including Rocky Point State Park in Warwick.
As debris makes its way into the water, Fulfer said it slowly breaks down over time into microplastics. Then, microscopic organisms, like zooplankton, confuse it for food.
“I’ve published a study looking at the impact on zooplankton which form the base of the food web, and we’re seeing that they are growing at much lower rates, they’re reproducing less, and they’re not living as long,” Fulfer said. “So this is important because if there are less zooplankton, that’s less food for fish. And that obviously has far-reaching implications.”
Fulfer said more research is needed to determine whether microplastics are causing the decline in the zooplankton population. Still, she is concerned about how those small plastics are affecting marine life and humans.
“We eat seafood and unfortunately our marine organisms are eating microplastics and then we eat them,” Fulfer said. “And so there’s potential that we are ingesting microplastics when we eat, when we eat our food.”
It’s also troubling to Jaime Ross, an assistant professor of neuroscience at URI. She has been studying the effects of microplastics in mammals.
“There’s not really anything known about plastics on brain health and neurological disease and also the life cycle of plastics in the body,” Ross said. “We really don’t know too much about it.”
Ross and her team exposed mice young and old to microplastics in drinking water over three weeks. After observing them in an open field, researchers found ingesting microplastics caused the mice to have changes in their behavior akin to dementia in humans.
“The young adult animals and the older adult animals, they both did things that they shouldn’t. They spent a lot of time in the center of the arena,” Ross said. “Mice are not supposed to really do that.”
Ross said she was surprised to see those results after three weeks of exposure.
“I thought perhaps if you’re chronically exposed for months and months, maybe you would see something like this, but only three weeks was really shocking to us,” she said.
Ross’ team also learned the plastic particles had begun to bioaccumulate in every organ in the mouse, including the brain.
“The fact that they are crossing the blood-brain barrier, which really is supposed to keep out bad things from the brain, including viruses and bacteria. The fact that they were able to sneak in there was almost alarming to us,” Ross said.
The mice that ingested microplastics had a decrease in glial fibrillary acidic protein, known as GFAP. It is a protein that supports many cell processes in the brain.
“It suggests that the microplastics could be changing the environment in the brain, and the brain is reacting to them in a way that could point to changes in cognition down the road,” Ross said.
Both researchers said there is an urgency to the work they are doing.
“I think we’re going to see a wide range of ecosystem impacts if we continue to create plastic and allow it to get into the environment,” Fulfer said. “I think eventually you would see widespread collapse of shellfish and fisheries.”
Inside her lab, Fulfer has slides full of microplastics she has collected from Narragansett Bay, ranging in size, shape and color. Many of the fragments are found in common everyday items.
“So three of the main types we found were polystyrene, which you might be familiar with as the white foam that we use in packaging, polypropylene and polyethylene,” Fulfer said. “Polypropylene and polyethylene are really common types of plastic used specifically in single-use plastics. So those are our takeout containers, our coffee cups, things like that.”
Littering is one way these plastics are getting into the water, but Fulfer said it is bigger than that.
“Microplastics take all kinds of forms, so we can have particles which are formed from the breakdown of larger items like bags or bottles, but we also have microfibers which mostly come from your clothing,” she said. “And so a lot of our clothing is unfortunately synthetic now that makes it last longer and have different qualities. So we like to use it, but unfortunately when you wash your clothes, those microfibers are being released and going into the wastewater.”
That is why Ross said she tries to buy cotton fabric when possible, among other changes she has made.
“I really try to always purchase a product that’s not in plastic. I try not to store our food in plastic. I try not to drink out of plastic,” Ross said. “Sometimes these things are not avoidable.”
As Ross continues her research, there are several key questions she is eager to answer, including: where do microplastics go once they enter the body and how long do they stay there?
“Another question is are they really contributing to this large uptick that we see in society of a lot of different inflammatory diseases and neurological disease? Are they contributing to our health in a negative way?” Ross said.
Ross hopes further analysis will shed light on the far-reaching effects of these materials. She said it is unknown if microplastics can leave the body or how to get rid of them.
“We need to really understand that black box of what are plastics doing to us and what plastics do we really need as a society for healthcare, for example, and what plastics can we part ways with and say, ‘We don’t need this,’” Ross said. “This is just to the benefit of packaging. This is not really helping us and we need to find an alternative either source or get rid of it.”
