Scientists who recently found soaring chemical levels in the blood of South Carolina alligators are trying to determine whether gator meat that hunters consume contains the same potentially harmful contaminants.
Researchers with the S.C. Department of Natural Resources and the U.S. Department of Commerce are analyzing alligator flesh to see whether the meat is tainted by perfluoroalkyl acids, a group of chemicals of increasing health concern.
These acids once were used as ingredients in water repellant surfaces, frying pan coatings, plastics and other products, but they are being phased out as researchers learn more about the potential toxic effects on people.
“One of the reasons to do this study is to look at ‘Is this actually in the meat people would eat?’ ’’ said Jessica Reiner, a Commerce Department scientist in Charleston.
“We want to make sure hunters can hunt, eat the meat and be well-informed.”
Perfluoroalkyl acids have, in some cases, been linked to cancer, birth defects, thyroid disease and immune system damage. The U.S. Environmental Protection Agency recently set a drinking water advisory limit for two types of the acids because of the potential dangers.
Since the state legalized public alligator hunts in 2008, sportsmen have killed more than 3,300 gators across South Carolina’s coastal plain.
It’s illegal for sportsmen who kill alligators during the public hunting season to sell the meat to restaurants, but many sportsmen eat portions of the gators they take.
State and federal researchers have collected 43 cuts of alligator meat for chemical analysis and hope to publish the results of their findings next year, said Reiner, one of the collaborators on the research project.
Key questions are whether high levels show up, and if so, whether people are eating enough alligator meat to threaten health.
Brad Taylor, an alligator hunting guide from Batesburg-Leesville, said he’d like to know more since past studies of other contaminants in alligator meat have been inconclusive. But he also questioned whether pollutants in alligator meat would have a major health impact because people don’t regularly consume gator flesh.
“There are probably worse things under your kitchen cabinet that you are breathing in every day than eating a piece of alligator meat,’’ he said.
The DNR-Commerce Department meat study follows a 2016 scientific report that is the first to identify potential hot spots for perfluoroalkyl acids in alligators.
Sites in South Carolina and Florida had some of the highest amounts of one type of perfluoroalkyl acid – known as PFOS – ever recorded in the blood of alligators and crocodiles, according to the 2016 study, which was led by scientists from the Medical University of South Carolina and the U.S. Department of Commerce. PFOS is a chemical once used to make Scotchguard.
Overall, perfluoroalkyl acids, a class of chemicals that do not break down easily in the environment, registered in alligators at Kiawah Island and Bear Island south of Charleston and at the Tom Yawkey Wildlife Center south of Georgetown, according to the study. About 15 types of the acids were analyzed.
The highest levels of some acids found were at Merritt Island, Fla., near the Kennedy Space Center, but some of the acids documented at the South Carolina sites were higher than at most other Florida locations. In addition to gators at three sites in South Carolina, alligators at nine sites in Florida were tested.
At this point, scientists don’t know why the elevated perfluoroalkyl acid levels showed up in alligators they checked in South Carolina. None of the sites near Charleston and Georgetown is heavily industrialized.
“I was a little bit surprised,’’ said Phil Wilkinson, a veteran biologist who collected blood samples from the gators for the study. “I think of problem areas as being closer to town.’’
It’s possible that gators living at Kiawah Island, the Yawkey Wildlife Center and Bear Island could have been consuming fish that swam to those areas from other, more contaminated spots, Reiner said. Separate studies are under way on fish in Florida that may tell more about the effects of perfluoroalkyl acids on certain species, she said.
Perfluoroalkyl acids are emerging contaminants of concern that have shown up in drinking water across the country, prompting questions about the toxic effects of consuming the tainted water regularly.
The Environmental Working Group, a non-profit environmental organization, analyzed federal data and reported that nearly 100 water systems serving 6.5 million people in 27 states contained elevated levels of one type of perfluoroalkyl acid.
That acid, known as PFOA, was found in drinking water for 24,000 residents of South Carolina, almost exclusively in the Upstate’s Spartanburg County, the group’s research shows. PFOA was at one time an ingredient in Teflon.
PFOAs have been tied to kidney and testicular cancer, birth defects, heart disease and complications for women during pregnancy, according to the Environmental Working Group.
These chemicals have been the subject of major lawsuits over the past 15 years, many in West Virginia and surrounding states. In one instance, a dump used by the DuPont chemical company for PFOA disposal was blamed for contaminating a farmer’s creek and killing his cows.
David Andrews, a senior scientist with the Environmental Working Group, said the buildup in alligators is not a shock, in some ways, because top predators tend to accumulate contaminants over time if they are regularly exposed.
Mercury, for instance, tends to build up in big alligators that eat mercury-tainted fish. In South Carolina, researchers with DNR and the S.C. Department of Health and Environmental Control are examining mercury levels in alligators, said Thomas Rainwater, a biologist who works with the Yawkey Wildlife Center and Clemson University.
Andrews said evidence shows that high levels of some perfluoroalkyl acids can cause cancer, but concerns also are increasing about the effects of lower levels on people.
Finding perfluoroalkyl acids in the blood of alligators serves as a “general warning about this class of chemicals,’’ he said. “They do happen to be extremely persistent’’ in the environment.