People shouldn't eat fish caught anywhere in Florida's Lake Okeechobee after a blue-green algae bloom near its center tested positive for hazardous toxin levels, an Audubon Florida biologist said Monday.

A bloom sampled June 5 in the open water about 10 miles southwest of Port Mayaca, Florida contained the toxin microcystin at a level of 17.6 parts per billion, according to test results the Florida Department of Environmental Protection released Monday.

Contact with water containing 8 parts per billion and higher is deemed hazardous to humans by the Environmental Protection Agency.

Microcystin can cause nausea and vomiting if ingested along with rashes and hay fever symptoms if touched or inhaled. The toxin also has been linked to long-term, sometimes fatal, liver disease.

Some scientists believe another toxin in blue-green algae known as BMAA can trigger neurological diseases.

"As a precaution, I'd say don't eat any fish from anywhere in the lake right now," said Paul Gray, an Audubon biologist who's been studying the lake for 30 years. "Even if you don't see algae in the water, there can still be toxins in the water because when the algae dies, the toxins remain."

Because the lake is so low — not quite 11 feet, which is about 2 feet, 3 inches below the average elevation for June 10 — most of the marshes on the west side of the lake are dry, Gray said, "and fish are out in the open water. Right now the whole lake is conducive to growing algae."

Algae sampling in the lake is limited, Gray said, "so we really don't know what all is out there. People should be careful. I wouldn't eat any fish from the lake, just as a precaution."

Mike Shellen of Buckhead Ridge, a 25-year fishing guide on the lake, said Gray is overreacting to a single bloom in a 730-square-mile lake.

"Paul needs to keep his mouth shut and not panic people," Shellen said. "I know people, whole families, who eat fish out of the lake every day and don't get sick."

Shellen said there have been algae blooms in Lake Okeechobee since he started fishing there and eating his catch 40 years ago.

"I'm not dead," he said. "I've never even gotten sick. Yeah, that's how dangerous the stuff is out there."

The World Health Organization says microcystin at levels up to 1 part per billion are safe to drink.

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