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Outdoors
Smoky Mountain News
Western Carolina University student Connor Stamey collects stoneflies at Coweeta. The stoneflies will then be analyzed for microplastic content. Donated photo
A million little pieces
Research indicates high levels of microplastics in WNC waters
Student researcher Olivia Swift stands with an array of digested samples. Donated photo
BY HOLLY KAYS STAFF WRITER Jason Love got interested in microplastics by way of mussels. A wildlife biologist by education and training, he’d long been interested in the reasons behind the decline of Southern Appalachian mussel species, and in particular that of the federally endangered Appalachian elktoe. He was interested while working in his
previous position as site manager for Coweeta Hydrologic Laboratory, and he’s interested now in his new position as associate director of the Highlands Biological Station. “It used to have a stronghold in the Little Tennessee River, but beginning around 2004/2005 the populations just crashed, and they’re possibility extirpated from the Little Tennessee,” Love said. “That motivated me to understand what’s going on.” In summer 2018, he had a few interns who needed a project to work on. Love saw that, while literature was starting to show that microplastics were showing up everywhere from the Arctic to the oceans, no research had yet been published examining the situation in Southeastern streams. So, with the students’ help, Love set about investigating the issue. Because the decline in mussel populations had originally spurred his curiosity, Love wanted to look at microplastic concentrations within mussels living in Western North Carolina. He decided to use Asian clams, in invasive exotic now found throughout the United States, since he figured folks wouldn’t object too strenuously to specimens from that particular species being digested in hydrogen peroxide for the sake of science. The team collected samples from the Little Tennessee, the Tuckasegee River and Cartoogechaye Creek. “We expected to find microplastics, particularly in the streams that had wastewater treatment plants, which is both the Little Tennessee and the Tuckasegee, but Cartoogechaye did not have a wastewater treatment plant,” said Love. Wastewater treatment plants are great at getting rid of fecal matter, but they’re not designed to filter out microplastics, Love explained. Microfibers are a big contributor to the microplastics load coming from these plants — with every load of laundry, a little bit of fiber works its way out of the clothing and into the water, and many wastewater systems have difficulty capturing those materials. So, microplastics in the samples taken near wastewater plants were expected. What Love did not expect to find, however, were high amounts of microplastics even in Cartoogechaye, which does not have a wastewater treatment plant. Just below Lake Emory in Franklin, the team found about 5.8 microplastic particles per mussel, the most of any of the sampling locations. At Cartoogechaye, the average was about 3.8 particles per mussel. When it’s broken down by gram, though, the ranking shifts. On a per-gram basis, Cartoogechaye had the highest levels of plastic, about 30 particles per gram compared to a low of about 1.7 on the Tuckasegee below Bryson City. Similar research examining the Yangtze River in China came out as Love was conducting his study, and it showed a range of 0.4 to 5.0 microplastics per gram — far fewer than what Love was finding in the Tuckasegee and Little Tennessee. However, it’s important to note
