Research suggests contaminants are moving along the coast and into the marine food web from a nearby Superfund site
By Bob Berwyn
SUMMIT COUNTY — Pollutants from electrical equipment, hydraulic fluids, paper manufacturing, printing inks and other sources is turning up at record-high concentrations in bottlenose dolphins living along the coast of Georgia.
Researchers with the National Oceanic and Atmospheric Administration reported last week that they found the highest levels of PCBs ever reported in marine mammals when they studied dolphins in the area in August 2009. The research was conducted by NOAA’s Center for Oceans and Human Health at the Hollings Marine Lab.
The dolphins were captured, given a physical exam and then released. The results showed decreased levels of thyroid hormones, elevated liver enzymes and indications of suppressed immune function in the animals. Researchers will test human health risks in nearby coast towns.
“When we received the lab results for the Georgia dolphins, we were alarmed by the contaminant levels and set out to investigate how these heavy chemical burdens were affecting their health,” said Dr. Lori Schwacke, co-lead investigator on the team.
As a result of the dolphin research, health officials will conduct a study in nearby coastal communities to determine whether coastal dolphin populations and humans sharing the same seafood resources experience similar exposures.
The term PCB encompasses a suite of persistent contaminants that have been banned in the United States since the late 1970s due to documented adverse health effects. The extraordinarily high levels of PCBs measured in the dolphins, a maximum concentration of 2900 parts per million, may be suppressing their immune function.
The PCB compounds found in the dolphins has a unique chemical signature that’s consistent with contaminants of concern at a Superfund site near Brunswick, Ga. Scientists are equally concerned about the high PCB levels in dolphins sampled near a marine protected area approximately 30 miles from Brunswick. This suggests that the contaminants are moving along the coast through the marine food web.