Research on Southwest Florida cyanobacterial blooms shows that the toxins they produce are aerosolized, potentially being inhaled by people far from contaminated water bodies.
Sometimes known as blue green algae, cyanobacteria anciently played an important role in establishing the oxygen atmosphere of the earth. When rivers, lakes, and estuaries are loaded with excess nitrogen and phosphorous, often the result of agricultural runoff or improperly treated sewage, cyanobacterial populations can explode, carrying toxins to the environment that can damage human health.
The nonprofit Brain Chemistry Labs in Jackson, Wyoming last year partnered with neurologists and oceanographers at the Miller School of Medicine in Miami, and marine biologists at Hubbs-SeaWorld Research Institute, and the Blue World Research Institute to announce that beached dolphins in the Indian River Lagoon, Florida show signs of Alzheimer's disease. Their brains had high concentrations of the neurotoxin 2,4-DAB, an isomer of BMAA produced by cyanobacteria. Now partnering with the nonprofit Calusa Waterkeeper in Fort Myers, Florida, the Wyoming scientists announced that they have identified airborne cyanobacterial toxins collected in special detectors that were placed in different locations in southwest Florida. All of the samples contained the neurotoxin 2,4-DAB, the same cyanobacterial toxin found in the dolphins.
“Data obtained from ADAM [Airborne Detection for Algae Monitoring] airborne detectors indicate that people may be chronically exposed to low concentrations of cyanobacterial toxins and that further assessment is required to help protect human health” the scientists announced in a paper published today in the journal Toxins .
Lead scientist Dr. James Metcalf said, “These data suggest that you don’t need to be close to toxic blooms to be exposed through breathing. We continue to find cyanobacterial toxins in air such as in our study of dust blown from the exposed lakebed of the Great Salt Lake in Utah.”
“Our research has shown that chronic low-level exposure to cyanobacterial toxins is a risk factor for ALS and potentially other neurodegenerative diseases,” adds Dr. Paul Cox, Brain Chemistry Labs Executive Director. The Wyoming team researched a dramatic increase of ALS among veterans suggesting that inhalation of cyanobacteria from desert dust in Kuwait and Iraq was the cause of the spike of ALS ten years after their deployment to Operation Desert Storm in 1993.
Brain Chemistry Labs has previously quantified high levels of cyanobacterial toxins in the Caloosahatchee and St. Lucie River, resulting from the release of cyanobacterial-laden waters from Lake Okeechobee. Research by neurologist Elijah Stommel at Dartmouth Medical School shows that individuals living close to lakes and estuaries with cyanobacterial blooms are at a significantly increased risk of ALS. Researchers have focused on consumption of contaminated food and water as the likely routes of exposure.
“Even though we can avoid contaminated food and water, preventing exposure through breathing is far more difficult,” Dr. Metcalf adds.
The article, “Developing Tools to Assess Airborne Cyanobacterial Toxins in Southwest Florida, USA,” can be downloaded from https://www.mdpi.com/2072-6651/18/7/309/pdf .
Toxins
Experimental study
Not applicable
Developing Tools to Assess Airborne Cyanobacterial Toxins in Southwest Florida, USA
16-Jul-2026
The authors cite no conflict of interest.