Science / Medicine : Study on Dolphin Deaths Hit

Six scientists last week disputed a government report blaming a naturally occurring toxin for the deaths of more than 740 dolphins found from New Jersey to Florida between June, 1987, and February, 1988. They told a House merchant marine and fisheries subcommittee that polychlorinated biphenyls (PCBs) and other contaminants played a larger role than mentioned in the report.

The scientists expressed skepticism of Canadian veterinarian Joseph Geraci’s conclusion that the bottlenose dolphins died from eating fish contaminated with a naturally occuring toxin--brevetoxin--present in “red tide” algae.

“There is a lack of evidence to support that brevetoxin was the major cause of these strandings; the facts support an alternate conclusion that organochlorine compounds and particularly PCBs had an important role in the strandings,” said Daniel Martineau, a Cornell University veterinarian. He said brevetoxin was found in just eight of 17 carcasses studied, while “large amounts” of PCBs were detected in all analyzed dolphins.