Thursday, October 28, 2021

Blue-Green Algae and Red Tide: How Harmful Are They?

Photos by Shirley Woolaway | Nick Penniman presented information on Blue-Green Algae and Red Tide.

A discussion on Climate Change by Nick Penniman, long involved in civic and environmental advocacy in Collier County, brought not only clarity on the subject to his listeners, but also a sense of urgency about the need to address what’s happening in our local area. Penniman spoke recently to members of the Naples League of Women Voters and guests with a presentation titled, “Red Tide, Blue-Green Algae and Human Health.”

Perhaps many of us have been affected by red tide, noticing some physical symptoms like coughing and other respiratory distress and wonder how harmful it is. According to Penniman, recent medical research shows about 80% of those with asthmatic conditions are affected by red tide, but that symptoms generally are not long-lasting once away from the source of the problem. 

Red tide, he explained, is a saltwater algae, whirling whip, that is single-celled and tiny with a wide tolerance for salinity and temperature with a diet cycle know as a “grazer.” When its cells are ruptured, their aerosolized polyether toxin is released as Brevetoxin. While there is currently no research connecting red tide to long-term human health issues, Penniman said shellfish and sea life are not so fortunate. Shellfish poisoning is common, as is the death of finfish that ingest through their gills. Manatee studies indicate more severe implications. One study showed lower lymphocyte counts and necropsy while a second study indicated manatees develop neuromuscular problems with higher levels of Brevetoxin from red tide in the liver, kidney, stomach and brain, which is caused from eating seagrass.

One slide showed sources of the problem as nutrients from the Mississippi River’s dead zone, coastal runoff, dissolved oxygen created by die-offs and an up-welling wind accounting for red tide issues on the Gulf coast.

According to Nick Penniman, blue-green algae is very different from red tide. It’s a freshwater algae known as Cyanobacteria, a bacteria with varying toxicity, depending on intensity. It is intolerant of saltwater. There are 28 different varieties in Lake Okeechobee with the main toxins Microcystis and Anabaena. Blue-green algae can get to the coast by water from Lake Okeechobee. 

Penniman said that nitrogen is not measured adequately in the lake and that phosphorus is at 30 ppb to 120 ppb and by 1990 the eutrophication of Lake Okeechobee was complete. Eutrophication is defined as an excessive richness of nutrients in a lake or body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.

Background information given on Florida’s water system includes hurricanes in 1926 and 1928 that led to the construction of the Hoover Dike. In 1947, flooding and drought in Miami-Dade and Broward Counties led to canalization by Central and South Florida. With the Hoover Dike now weakened, the Corps of Engineers is solely responsible for releases to Caloosahatchee and St. Lucie outlets both in the quantity and timing of water releases. 

The governmental group responsible for water quality is the South Florida Water Management District, created in 1972 by the legislature. The five created districts conform to watershed boundaries. The district is governed by an appointed board with ad valorem (based on the value of the transaction) taxing powers subject to legislative oversight. It controls water quality and consumption permits for all of South Florida.

The blue-green algae’s cell walls in Lake Okeechobee are affected by salinity. Penniman’s slide indicated the effect of 18 PSU (Practical Salinity Unit) with the Microcystis bacteria diminished in size and a bright green rather than rosy pink because of the salinity. For comparison, according to Wikipedia, water at 0.05% or below is freshwater. Salinity in the Great Salt Lake in Utah can vary between 142 to 317 PSU. 

Penniman also highlighted information from a January 2018 issue of Fortune magazine about researchers looking at links between the blue-green algae, Cyanotoxins like Microsystis and Beta-methylamino-L-alanine (BMAA) and neurodegenerative diseases like Parkinson’s, ALS or Lou Gehrig’ s disease and Alzheimer’s. Some studies show a connection between blue-green algae and human health, and researchers continue to work in this area.

As described in the Fortune article, reports of these diseases in a cluster drew the attention of ethnobotanist Paul Cox, who leads the non-profit Brain Chemistry Labs in Jackson Hole, WY. He and his team of researchers visited Guam and learned that a delicacy of the Chamorro people was a bat boiled in milk—eyeballs, wings and all. The bat’s diet consists of seeds from the cycad tree. When tested, the toxin BMAA was found in the seeds that caused symptoms in monkeys like the Chamorro people exhibited, but further testing revealed one would have to eat a ton of cycad flour from the seeds for the toxin to have an effect.

Further research found that the cycad trees get their sustenance from strange, coral-like aerial roots. Cox found Cyanobacteria in those roots. Also, BMAA was discovered in the brain tissue of Chamorro who had died of neurodegenerative diseases. The article points out that cyanobacteria is all around us in lakes, puddles and ponds. These bacteria are loaded with toxins, including BMAA. 

Cox earned his Ph.D. in biology from Harvard and undergraduate degrees in botany and philosophy from Brigham Young University. He has brought in scientists who have filled the gaps in his own training after speaking with up to 50 people in 28 labs in over a dozen countries with the same pitch: “Please stop what you’re doing and help us solve Alzheimer’s and ALS.” Researchers responded to his pitch and became part of the research consortium.

Cox’s work has been cited more than 12,000 times in scientific journals, the Fortune article stated. He is the consortium’s leader of scientists who work on their own or with others and gather once a year to compare findings. Marine biologist Larry Brand said, “We’re all in different fields. We present our results and try to connect the dots on everything from causes of algae bloom to medical problems to possible prevention and treatment.” Brand is trying to figure out how much BMAA is getting in the food chain via crabs, shrimp and other marine life that can be found in those blooms. He has discovered that certain blue crabs off the coast of Florida, commonly eaten by humans, had levels of BMAA as high as the bats in Guam. “If BMAA were a man-made chemical,” he said, “I don’t think it would ever be allowed to be added to food.”

Cox believed BMAA insinuated itself into the brain in place of one of the 20 standard amino acids. He and his team found it was passing for L-serine. Researchers continue to test L-serine, an amino acid that appears to nullify the effect of Cyanotoxins and BMAA. While these findings will require further research, there is a confirmed connection between blue-green algae and non-alcoholic liver disease. In addition, dolphin studies have confirmed BMAA in dolphin brains. Negative effects depend upon high levels of concentration and the length of exposure time with multiple factors affecting the contraction of disease. Studies are ongoing.

Penniman stated his presentation had been reviewed by M.D. and Ph.D. sources as he is not a doctor. Long involved in environmental advocacy, Penniman is chair emeritus of the Conservancy of Southwest Florida, a former member of Collier County’s Coastal Advisory Committee and the Environmental Advisory Committee. He is a trustee of the Everglades Foundation and board chair of the Smithsonian Environmental Research Center. He wrote “Nature’s Steward: A History of the Conservancy of Southwest Florida,” published in 2014 and has a new book being published before the end of the year tentatively titled, “Toxic Mix: Red Tide, Blue-Green Algae and Florida Politics.”

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