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Toxic Algae Blooms Muck Up South Florida Waters

Toxic algae blooms that are killing marine life in South Florida and making the waterways inaccessible to residents have researchers and public officials working together on a solution.

GAINESVILLE, Fla. (CN) - Toxic algae blooms that are killing marine life in South Florida and making the waterways inaccessible to residents have researchers and public officials working together on a solution.

“This is a problem that has been a long time in the making, and it’s gonna take a long time to fix,” John Maehl, ecosystem manager for Martin County, said in an interview. “Right now there’s a lot of attention on removing blue green algae, and we’re dealing with an acute symptom. People are suffering at marinas. Homeowners on the lake, people are having trouble recreating on the water. We’re gonna do our best to address those issues in an acute sense, but we really need to keep our focus on the long term solutions that prevent this in the first place.”

Algae is of course naturally occurring all over the world. While sea life such as coral benefit from the organism, algae growth becomes a problem when human activities such as development or the use of fertilizer increase the amount of nutrients in the water for algae to consume.

Dee Ann Miller, a spokeswoman for the Florida Department of Environmental Protection, explained that Florida is actually experiencing two distinct algal blooms: one “red tide, the other is blue-green algae.”

Red tide can live in salt waters only but, blue-green algae, also known as cyanobacteria, is found in freshwater and brackish environments.

The latter algae thrives in warm conditions, in stagnant or low flow waters, and in conditions with a lot of nutrients- namely nitrogen and phosphorous. Exacerbated by Hurricane Irma, the blue-green algae has been spotted not too far from Lake Okeechobee, in Marin and Palm Beach.

“If there is more (nitrogen and phosphorus) than the soil can consume, then when it rains, it’s going to leech those nutrients into the water, and then they’re in the water until something consumes them, and algae loves it,” explained Maehl, whose division manages water quality for the river, estuary and inlet in Martin County.

“It’s an important role for Martin County because of the estuary,” Maehl said. “We have a pretty significant river and watershed that discharges to the ocean, and a lot of people live on it, a lot of people recreate on it, it’s a pretty critical habitat for marine ecosystems.”

H. Dail Laughinghouse, an assistant professor of applied phycology for the University of Florida/Institute of Food and Agricultural Sciences, called it critical for people need to understand this is a human-caused problem.

“With climate change there will be more global warming and then (more) nutrients,” he said.

Maehl made a similar point. “We all play a part in this,” Maehl said. “From fertilizing lawns, to golf courses, to agriculture - if you live in a that watershed, whatever you do ultimately impacts the water.”

Miller with the Florida Department of Environmental Protection meanwhile noted that restoration work to improve water quality could reduce nutrients and lessen the negative effects of algal blooms.

“Examples of these projects include building stormwater treatment areas, expanding and upgrading stormwater systems and wastewater treatment facilities, and fertilizer ordinances and best management practices,” Miller added.

Individuals involved with algae cleanup agree the discharge of Lake Okeechobee is a large source to blame, citing the lake’s excessive nutrient levels as a major contributor for the algae’s growth.

“When you open up the gate to allow Lake Okeechobee water in, at the rate of 2,000 to sometimes 6,000 cubic feet per second, you basically have taken on the entire watershed of Lake Okeechobee into the estuary, and that’s massive,” said Maehl.

“It’s either the volume of the freshwater or it’s the nutrient loads that Lake Okeechobee has - it has massive amount of nutrients (due to) years and years of water mismanagement,” Maehl said.

Discharges take place to alleviate Lake Okeechobee of excess accumulated water after events like hurricanes and large rainfalls.

The accumulation blue-green algae is dangerous because degradation of the algae causes its cell walls to become permeable, allowing previously enclosed toxins to escape.

“There are several thousand toxins, and they keep finding new ones,” said Laughinghouse, who studies found a lot of microcystin (liver toxins) in algae samples that were sent to him.

Even waters that appears clear could be a breeding ground for algal toxins, which can cause tumors, liver damage and neurological damage, Laughinghouse added.

“The toxin microcystin is very stable in the environment,” Laughinghouse said. “If you boil the water it doesn’t degrade it.”

The academic also cited evidence that these toxins are aerosolized. “People that live in areas that have a lot of blooms have more cases of liver cancer from nonalcohol that other places,” he said.

Teams like Maehl’s go out on a daily basis to monitor the blooms, and work to inform the public about their adverse health effects.

“We do know just anecdotally that people will get sore throats around it and can have respiratory symptoms after having been around it, and we definitely know you don’t want to be swimming in it or ingesting it,” Maehl said. “There is some federal funding that’s been earmarked to do some studies on the health effects, and to understand it better so we can give better guidance to the public about how to stay safe with it.”

In terms of solving the algae overgrowth issue, Laughinghouse cites potential solutions such as: Bali straw, copper, hydrogen peroxide and blue dyes. Hydrogen peroxide quickly deteriorates back into water, and the blue dyes stop the photosynthesis process from occurring. Clay was an attempted solution, but heavy rains cause the clay to float to the top of the waters, no longer serving to keep algae contained beneath it.

To track the status of red tide, and check up on the status of the algal blooms, you can visit DEP websites: and

Categories / Environment, Government, Health

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