Algal Bloom at Doctors Lake Marina, Credit: Rusty Gardner

St. Johns Riverkeeper Press Release: 
Friday, October 18, 2013

Jacksonville, FL — Today, the St. Johns River Water Management District (SJRWMD) released the results from two algae samples recently taken from the St. Johns River at Doctors Lake Marina in Clay County. The test results from GreenWater Laboratories detected total microcystin toxin levels at 1120 and 4350 micrograms per liter, or more than 50 and 200 times higher than the recommended recreational exposure threshold of 20 micrograms per liter from the World Health Organization (WHO). Attached are the lab results.

Last week, St. Johns Riverkeeper, a nonprofit advocacy group for the St. Johns River, took samples from the river at Jacksonville University, and the test results detected microcystin toxin levels at 1085 and 2080 micrograms per liter. Since that time, St. Johns Riverkeeper has received numerous reports of algal blooms throughout Clay, St. Johns, and Duval Counties. The number of algal blooms reported and the alarming toxic levels from St. Johns Riverkeeper's sample results prompted the St. Johns River Water Management District to do more sampling.

"We were alarmed when our sample results came back with such high levels of algal toxins," states Lisa Rinaman, the St. Johns Riverkeeper. "We are even more concerned now after seeing the recent results from the St. Johns River Water Management District's sampling. It is clearly time to put an end to the nutrient pollution problem that is fueling these toxic algal blooms, putting the health of our river and our citizens at risk."

Rinaman continues, "It is important that the public understand the risks from exposure and avoid contact with any algal blooms they may encounter."

Algal blooms often occur as a result of excessive concentration of nutrients in our river and waterways. Too much nitrogen and phosphorous can feed uncontrolled algal blooms that deplete oxygen in the water needed by fish, reduce light that is essential to submerged vegetation, and threaten the health of both humans and aquatic life. Excess nutrients result from failing septic tanks, manure, wastewater discharges, stormwater runoff, and fertilizers that regularly wash into the river.

The Florida Department of Health in Duval County recently released a statement with these safety tips: "Blue-green algae toxins can affect the liver, nervous system and skin. Most problems happen when water containing high toxin amounts is ingested. Abdominal cramps, nausea, diarrhea, and vomiting may occur if any untreated surface water is swallowed. Direct contact or breathing airborne droplets containing high levels of algal toxins during swimming or showering can cause irritation of the skin, eyes, nose and throat. Rashes can develop when skin is exposed to the algae. Individuals should avoid coming in to contact with a blue-green algae bloom, especially children and pets. Boiling water does not remove or destroy these toxins. DOH-Duval recommends people refrain from recreational water uses that could result in ingestion of and/or skin exposure to algal blooms in the river. Children should also not be allowed to play along the shoreline where they might be exposed to clumps of algae or drink water from the river. FDOH also recommends that fish caught in or near the bloom not be consumed."

We all can make a difference by reducing our use of fertilizers, preventing runoff, maintaining septic tanks, and adopting other River Friendly practices. Learn more on the River Friendly section of our website.