The state on Wednesday tightened its recommendations on how much Lake Norman hybrid striped bass people should eat, after elevated levels of PCBs showed up again in a review of fish tissue data.
Eat no more than two meals a week of hybrid striped bass from the lake, the N.C. Department of Health and Human Services advised.
The fish consumption advisory is based on an increased risk for liver and immune system problems for people who eat hybrid striped bass contaminated with PCBs. The advisory is for fish caught in all parts of the lake, including in Catawba, Iredell, Lincoln and Mecklenburg counties.
PCBs, or polychlorinated biphenyls, were used for decades to insulate and lubricate a vast range of products – from electrical transformers and capacitors to caulk and paint still found in old buildings. They don’t go away once the products do, leaving a long-lasting toxic impact.
Ingested in large doses, PCBs can hurt the neurological development of children, the reproductive and immune systems, and may cause cancer. The chemicals can also put at risk brain development in the unborn babies of pregnant women who eat contaminated fish.
The PCB fish contamination does not present a known health risk for people wading, swimming or boating in the lake, handling the fish or touching the water, the state said.
In April, the state issued a similar advisory but advised eating no more than four meals of Lake Norman hybrid striped bass per week because of PCBs in the fish.
A 2013 advisory is still in effect regarding how much Lake Norman largemouth and striped bass should be consumed. Pregnant women, nursing women, women who may become pregnant, and children under 15 should not eat any striped bass or largemouth bass from the lake, the state advised. To guard against mercury exposure and potential PCB exposure, other people should not eat more than two meals a month of largemouth bass and one meal a week of striped bass from Lake Norman. A meal of fish is considered about six ounces of uncooked fish.
Levels of PCBs in Lake Norman striped bass exceeded the state “action level” for PCBs of 0.05 mg/kg in April 2013. Because previous studies showed that largemouth bass in all waters of North Carolina have elevated levels of mercury, the Lake Norman advisory also includes largemouth bass.
A statewide list of fish advisories is available at http://epi.publichealth.nc.gov/oee/fish/advisories.html.
Staff writer Bruce Henderson contributed.