By October, anglers on Lake Wylie could find out just how safe it is to eat the fish they catch.
Unsafe carcinogen levels in fish caught Lake Wateree have led the state to issue fish consumption advisories. It has also tested Lake Wylie and three other upstream sites to find the cause.
"We ended up focusing more of our attention on the Catawba basin," state official Chuck Gorman told the Catawba-Wateree River Basin Advisory Commission last week in Rock Hill. "A lot of people are interested in what we find out upstream."
Commercial use of polychlorinated biphenlys or PCBs was banned in the 1970s. The chlorine-based synthetic compound has been linked to cancer and can affect the immune, reproductive and nervous systems, according to the U.S. Environmental Protection Agency.
Women who may become pregnant and small children should not consume PCBs, said Gorman, with the South Carolina Department of Health and Environmental Control Bureau of Water.
"PCBs can remain in the environment for many years, and they can get into the tissue of the fish," Gorman said. "They actually move with the sediment down the river system."
Gary Faulkenberry, who represents the Wateree Homeowners Association on the commission, said the finding of unsafe levels of PCBs in Wateree are curious since there aren't large manufacturers there. Wateree and Lake Hartwell are the only two lakes in South Carolina under fishing advisories because of PCB content.
"Would it not then be an assumption that it came downstream?" Faulkenberry asked.
Late last year, the EPA released a survey of 500 lakes nationwide for PCB concentrations. Despite a lack of commercial production for almost 40 years, all 500 lakes showed the presence of PCBs.
Of the 500 lake samples, 17 percent - including Lake Wateree - showed PCB levels exceeding federal water quality standards. Based on the amounts found and additional state testing, the state Department of Health and Environment Control put out an advisory. Largemouth bass from Wateree should be eaten no more than one meal per week and striped bass and blue catfish not more than once per month.
The state agency also used tests from the Catawba Riverkeeper Foundation on Mountain Island Lake just north of Lake Wylie to determine that testing between Lake Wateree and Mountain Island Lake was necessary. Jay Sauber, of the North Carolina Department of Environment and Natural Resources, said those same tests showed an increased need for his state testing Mountain Island Lake. Riverkeeper results put PCB content in the fish advisory range despite EPA data showing lower concentrations.
Sauber said 12 additional samples from Mountain Island Lake are in the lab, but warned PCB content is not as simple as "strictly an upstream to downstream transport." PCBs can be found in the atmosphere and rain, thus showing up in water that runs into the lake. Some lakes completely segregated from industrial uses, he said, show PCB content.
Gorman said he expects to have Lake Wylie fish results back in October.
"If that dictates us putting out an advisory, we will," he said.
The results should not prompt "no swim" advisories, he said. A fish consumption advisory would allow fish consumption but only to specific amounts. Gorman's department prints out 50,000 advisories annually, with information at boat ramps and in other locations, such as doctor offices for pediatrics and pregnant women.