Researchers have found per- and polyfluoroalkyl substances (PFAS) in every step of the Yadkin-Pee Dee River food chain
Researchers from North Carolina State University found per- and polyfluoroalkyl substances (PFAS) in every step of the Yadkin-Pee Dee River food chain.
The river does not have a known industrial input of these compounds.
The study examined the entire aquatic ecosystem for PFAS compounds, identifying links between ecosystem groups that lead to biomagnification, reported Science Daily.
"These compounds are engineered to be persistent on purpose; this is how they keep stains off your couch and eggs from sticking to your frying pan," said Tom Kwak, unit leader of NC Cooperative Fish and Wildlife Research Unit, professor of applied ecology at NC State, and co-author of the study. "We pay the price for these compounds when they enter the aquatic ecosystem."
The study measured PFAS contamination levels along the entire food chain of the river, identifying two PFAS hot spots along the Pee Dee.
The team collected samples of: water, sediment, algae, plant, insect, fish, crayfish, and mollusk. These samples were taken at five study sites along the length of the Yadkin-Pee Dee River. Researchers analyzed the samples for 14 different PFAS compounds, according to Science Daily.
Nearly every sample contained PFAS compounds and the site with the greatest PFAS concentrations was downstream of the Rocky River input, according to the study. This site drains part of the watershed from Charlotte, North Carolina and the surrounding area. The site with the second greatest PFAS concentrations was downstream in South Carolina.
The largest concentrations of 10 of the 14 PFAS compounds measured were in biofilm samples. Aquatic insects had the greatest accumulation of PFAS compounds of all the living organisms the researchers sampled, since they primarily eat biofilm.
"We are part of the food chain and when we ingest these foods, we accumulate their PFAS loads, too," said Greg Cope, William Neal Reynolds Distinguished Professor of Applied Ecology, coordinator of the NC State Agromedicine Institute, and corresponding author of the study. "This gives new meaning to the phrase, 'You are what you eat.'"