Why Is Florida’s ‘Unprecedented’ Algae Bloom Toxic?

By Nathaniel Scharping | July 6, 2016 10:11 am

Footage from a drone video of the bloom. (Credit: Dylan Hansen/Balance For Earth)

Massive blooms of potentially toxic cyanobacteria are washing onto beaches in Florida, keeping beach goers at home and raising concerns about possible impacts on public health.

The bacteria belong to the genus microcystis, meaning they are not technically algae, and are known to appear in areas with high concentrations of nitrogen and phosphorus. Both compounds leach into Florida’s Lake Okeechobee from industrial farming activities in the area. And when conditions are right, the blooms produce a toxin that can cause kidney and liver damage, as well as painful rashes in those exposed to it.

Many Factors

A confluence of events likely contributed to this season’s outbreak of microcystis, which migrated down the St. Lucie river to the Atlantic Ocean, where blooms are inundating beaches and suffocating tourism. Lake Okeechobee is bounded by a series of dikes maintained by the U.S. Army Corps of Engineers, a system that is some 80 years old and in need of repairs, reports the New York Times.

In El Niño years, the region tends to see more rain, and the Army Corps releases more water from the lake to prevent flooding, a process that started about two weeks ago — and it has since reduced the flow of water. While such blooms occur with more regularity in the lake itself, when nitrogen- and phosphorus-laden water is discharged through the St. Lucie and allowed to flow into the ocean it can trigger massive blue-green blooms like the one currently swamping the coast.

Microcystis needs both phosphorus and nitrogen to grow, and nitrogen is also used to produce the toxins that make it dangerous, says Richard Stumpf, an oceanographer with the NOAA who studies algae blooms. The algae produce both neurotoxins and hepatotoxins, which affect the liver and digestive system.


Microcystis aeruginosa (Credit: Wikimedia Commons)

Lake Okeechobee possesses high levels of both chemical elements as a result of intense fertilizer use in the region, much of which eventually makes its way into the lake. Microcystis comes in both toxic and non-toxic strains, says Stumpf, and the potential for toxicity depends on which strain is able to outcompete the others, in addition to how much nitrogen is available in the water. The exact role that the toxin produced by microcystis plays in the cyanobacteria physiology is unclear, but it may help the bacteria help hold on to precious nitrogen. It may also serve as a deterrent for the shellfish and other small marine animals that eat microcystis.

“A bloom, when it starts off, there can be a lot of nitrogen, and then it gradually gets used up … typically, blooms become less toxic as they progress,” says Stumpf. “If there’s a lot of nitrogen, then they can make the toxin, if there’s insufficient nitrogen for their cellular work, they won’t.”

Toxicity Confirmed

As the BBC reports, testing the bacterial blooms has confirmed that they are indeed toxic. Florida Gov. Rick Scott has declared a state of emergency in the four counties hit hardest by microcystis.

Algae blooms can become deadly if left unreported, especially in developing countries. The WHO reports that 42 people died in 1988 after drinking water from a cyanobacteria-contaminated reservoir in Brazil. A similar event occurred in Australia, where some 140 people developed symptoms of liver disease after blooms were reported in a nearby reservoir. Such cases are usually easy to deal with, although the fact that the cyanobacteria blooms in Florida occur over a wide area make treating them much more difficult. Still, the main danger to humans is from drinking contaminated water, so the impact on public health should be negligible if residents follow the safety precautions.

In addition to mammals, the blooms are also harmful to fish populations in the area. When the bacteria begin to rot they suck oxygen out of the water, causing fish to suffocate and die.

Stumpf says that there’s not much to be done at the moment. While chemicals such as peroxide and more natural treatments such as packets of barley straw have been shown to kill off blooms in small, contained areas, the sheer size of the microcystis invasion, combined with the presence of tides, makes it very difficult to clear the blooms.

He emphasized that preventative tactics are needed to control future blooms, and regulating the levels of chemical runoff in Lake Okeechobee is a primary concern. Because the bacteria need nitrogen to both survive and produce toxins, reducing nitrogen levels could significantly impact the amount of cyanobacteria in the water.

  • http://plus.google.com/CadeJohnson delbarco

    Although Governor Scott has blamed the problem on inaction by the Corps of Engineers, and this article mentions that the dikes are in need of repairs; it is not clear from this article how dike repairs would mitigate the problem. It seems that the problem is primarily one of chemical runoff – not an issue under the control of the Corps of Engineers.

    • jerry

      Finally, an informed opinion!

      The problem is not because of Lake Okeechobee. If it was the lake would suffer from the same issues. The problem is because the Army Corps of Engineers has prevented drainage from the lake because the water level wasn’t high enough.

      When heavy rains came a few months ago the Corps was caught off guard because high water is not a typical problem during the Spring season. When the Corps started releasing lake water into river beds that had been basically dry for months the water flushed out fertilizer run-off that had been accumulating for months. All of that sewage travelled toward the ocean through slow flowing streams bathed in lots of Sun. Of course, the algae came to life. Locals immediately started complaining about river pollution but the Corps chose to believe the issue would quickly pass – it didn’t.

      The problem is not a political kicking point, it’s simply a case of mismanagement due to Florida-influenced mismanagement or malmanagement (in the case of the governor’s office). The solution is for Florida to participate as a partner with the Army Corps of Engineers.

  • Charles Shaffer

    This is being caused by human activity. It’s basically the same issue as the dead zones found at the mouth of rivers like the Mississippi in the the Gulf of Mexico. The question is what is more important? The health of the oceans and the living things that depend on them or profit?

    • Kelly King

      human activity that includes manuals of best practices on a schedule… when an atypical situation (like an el nino or unusual activity, like rain or other change happens) those manuals written by gov oversight desk types are no longer the “best practices” but rather a detriment… waiting for a “certain season on a calendar” worked when the weather was predictable! now that it is not predictable we might need to consider letting some water out of Lake O before certain benchmarks are met, like a season or a water line.

  • Cal Bezemer

    Scriptures predict the poisoning of a high percentage of water & the ocean in “the last days” (of the. evil world system) before the Lord Yeshua/ Jesus comes to restore the Kingdom of Heaven on Earth. Lord help us to know how to deal with this human-caused crisis. Thank You. Sezme, CB/ Rev Bez

    • ozonator

      Yesterday, Loser Limbaugh was saying that his hired liars were calling for global cooling and your poisons were necessary for crops. While everyone in the extreme GOP is a god, a non-extreme Jesus won’t even be allowed to vote, would be lumped in with non-NRA worshipers, and would wonder why they removed at least 3 of the 10 Commandments.

      • OWilson

        Are those the Clinton Commandments you are talking about? :)

        • ozonator

          Why do you ____s insist on affixing religions to everyone but yourselves?

          • OWilson

            I’m an atheist :)

  • Yawrate

    It’s the fault of George Bush.

    • OWilson

      Get up to date.

      Now it’s Trump!!!!

  • Fawkes Guy

    Here is a great idea of how to fix the problem…let’s focus on who to blame over how to actually correct it!

  • Clayton Clemens

    AG is 33% of Florida’s economy, why don’t they look at the 40,000+ septic tanks leaking into the lake.

    • skeptic2525

      Did you even read the article? The algae blooms are caused by nitrogen and phosphorous pollution from industrial farming. Septic tanks leak effluent, not nitrogen and phosphorous.

  • Jane Doe

    organic farming anyone?

    • westerndream

      It would help but the natural flow and filtration of the watershed has been grossly averted from seeping thru hundreds of miles of grass, marsh and swamp to dumped in a straight line canal hell bent on the Sea. Or other parts ……w/out some meandering of flow of water disaster looms for years to come…

  • veritasspiritus

    This affair appears to be yet another chapter in how a given civilization destroys itself.
    Principally it is The River of Greed. Like the Amazon, there are countless tributaries but it is safe to say that capitalism left unchecked will be and will describe the blueprint and definition for destroying itself and all it’s adherents.
    My idea? We could make modest steps to correct so many environmental problems, invariably however someone yells out “That will ruin my business!” — OK on the other hand then, lets just ruin the planet.


    • 99rider


    • OWilson

      There are many “businesses” that are in the “business” of feeding the world’s population.

      Do you know where that stuff you see in your supermarket actually comes from, and how it gets to you?

      Any clue at all?

      Or can we assume you grow your own, and live without piped in water, gas, electricity, telephone land line, cell phone, cable TV and internet? :)

    • Pas Argenio

      Correct. We fling ourselves headlong in the quest for more until we are a bunch of fat, fearful people driving oversized cars. Florida will be under water by mid-century at our current rate anyway.

      • OWilson

        At your current rate of deficit spending and borrowing money you can never repay, there will be no U.S.A.

        It will have defaulted to it’s creditors. :)

        • Pas Argenio

          not to quibble as it was an issue for me also under Reagan, Bush I and Bush II (but they weren’t fighting the great recession)

          • OWilson

            Not really.

            I have a budget I have to live by. If I spend on what I WANT NOW!, unless I die before the bills become due and leave them all to some other poor sap, I could be in financial trouble.

            To saddle the unborn with the debt you incur now is unconstitutional. Taxation without representation, which can lead to all kinds of civil and military disobedience.

            It is how your country actually came to be! :)

            The fact that it is morally grossly and obscenely selfish, is another matter entirely :)

          • westerndream

            Its a PONZI for sure

  • ozonator

    Lucky the Olympics are being held in Rio … maybe

  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    We must abandon sciential Evil-Eye Q hate language and embrace Progressive solutions. If it were mosquito-borne (e.g., Zika), Republicants would demand the death of all female mosquitoes and Democraps the death of all male mosquitoes. The obvious compromise is the death of half of each, plus more studies.

    The obvious Progressive solution is not to address alleged cyanobacterial stateful bioterrorist rumored incidents. The obvious solution is a rainbow coalition of cyano-, magental-, and yellow-bacterial activists, plus more studies.

  • zlop

    Don’t fuss over it — Scoop it and cook it.

    • OWilson

      Nitrogen rich, can be cultivated for livestock feed/fertilizer.


      “Algae grow much faster than food crops, and can produce hundreds of times more oil per unit area than conventional crops such as rapeseed, palms, soybeans, or jatropha.[41] As algae have a harvesting cycle of 1–10 days, their cultivation permits several harvests in a very short time-frame, a strategy differing from that associated with annual crops.[38] In addition, algae can be grown on land unsuitable for terrestrial crops, including arid land and land with excessively saline soil, minimizing competition with agriculture”.

      • zlop

        Ferment it to make a cheese like substance, tempura?
        Must be something quick, like frying eggs?
        I heard about “Red Tide” — how to process that?

        • OWilson

          Strong leadership, and Free Markets?

          • zlop

            Snails and sunfish live in scum ponds and
            moose thrive on pond plants. The nutrition is there.

      • Dano2

        This algae is toxic. Get some facts.



        • OWilson

          Go troll WIKI


          • Dano2

            Thanks, LOLO. Learn something.



  • zec_afonso

    Years and years of electing anti-regulation, anti-environment corporate shills to office, this is what you get. Whatever is good and worthwhile about visiting or living in Florida — the natural environment, the Everglades, the beaches and oceans, the wild, undeveloped areas — is destroyed or on its way to being destroyed. Good job, Floridians.

  • westerndream

    This has been a catastrophe waiting to happen for decades. The Turkeys (politicians ) have finally come home to roost on our behest because WE keep electing the same crack pots looking for different outcomes. INSANITY. Put on your big boy and girl pants and demand meaningful change in the Florida watershed resource. My heart goes out to one and all and lets hope a Hurricane doesnt make all this concern for naught. GL and God Bless

  • http://www.youtube.com/brycesail Bryce

    The final solution is soylent green



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