Home » Admin » Wave Weekly » That algae in the St. Johns may produce toxins, JU Prof. Andy Ouellette says in First Coast News report (WITH UPDATE)

That algae in the St. Johns may produce toxins, JU Prof. Andy Ouellette says in First Coast News report (WITH UPDATE)

Biology Prof. Andy Ouellette, co-chair of JU's Biology and Marine Science Department
St. Johns Riverkeeper Lisa Rinaman and JU Biology Prof. Andy Ouellette take algae samples in the St. Johns River near

The abundance of green algae in the St. Johns River is not just unattractive – it may produce toxins, Jacksonville University Biology Prof. Andy Ouellette told Jacksonville’s First Coast News (WTLV NBC-12 and WJXX ABC-25) in a Wednesday, Sept. 4 report.

Ouellette and St. Johns Riverkeeper Lisa Rinaman took samples Wednesday to determine if it safe for swimmers to participate in Saturday’s “Up the River Downtown” event, and submitted the samples for laboratory testing.

Rinaman said the algae’s presence is a result of an excess of nitrogen and phosphorous in the water. Among the causes: Fertilizer and poorly maintained septic tanks.

“I did look at a sample this morning under the microscope and it confirms there are Microcystis colonies,” Ouellette, co-chair of JU’s Biology and Marine Science Department, said in the First Coast News report. “And so the question is, are they producing toxins, and if they are, how much?”

UPDATE: On Friday, Ouellette revealed lab results to Wave Weekly.

“The results came back from Greenwater Laboratories, and the levels of microcystin toxins are high, but below the levels that the World Health Organization uses for its moderate health alert for recreational waters,” he said. “But that does not mean that it is safe to swim in (the river); these are liver toxins, so small amounts of liver damage can go unnoticed.”

Ouellette also said that varying environmental conditions “can trigger the bloom to grow faster and can increase the level of toxin production in a localized area.”

Click here to read the First Coast News article and view a slide show illustrating the proliferation of the algae in the St. Johns River.