A “toxic puzzle” is what first led ethnobotanist Dr. Paul Alan Cox to Guam, where the researcher spoke with the indigenous Chamorro people of two different villages about a paralytic disease that was affecting about a quarter of adults.
What Cox and others found was that a neurotoxin, called β-Methylamino-L-alanine or BMAA, had accumulated in Chamorron food sources, likely causing the disease symptoms.
“ Our thought was that this was sort of like Rosetta Stone,” Cox said. “If we could figure out what was going on in these villages, we might get deeper insights into how these diseases are related elsewhere.”
BMAA is produced by cyanobacteria — also commonly referred to as blue-green algae — and can be found in freshwater, estuaries and marine waters in Florida and across the globe.
A couple decades after the initial findings on Guam, a collection of researchers around the world are finding a strong link between environmental exposure to BMAA in cyanobacteria and degenerative nerve diseases like ALS, and possibly Alzheimer’s.
“ What we're really interested in is first of all demonstrating there's a strong link between environmental degradation and loss of human health,” Cox said.
READ MORE: Florida allocates money to Mote Marine Lab to fight harmful algal blooms
The group, Brain Chemistry Labs, is a consortium of 50 scientists across 12 countries from various disciplines including neurology, microbiology, ecology, and more. Together, they’re connecting the dots between this neurotoxin in our environment and deadly diseases. They’ve studied BMAA and other algal toxins appearing in Florida waters, including during a particularly incessant Red Tide event in 2018 in Western Florida.
“ We think that preventing exposure to some degree will prevent some of the neurodegenerative illnesses that we've been studying,” Cox said.
WLRN spoke to Dr. Paul Alan Cox on a recent trip to Palm Beach about the Brain Chemistry Labs Findings, and their implications for Floridians periodically exposed to toxic algal blooms. The conversation was edited for brevity and clarity.
WLRN: Can you briefly describe where you began with this work linking blue-green algae to degenerative diseases like ALS and Alzheimer’s?
COX: We were really puzzled by a curious paralytic disease on the island of Guam. In two villages, Humåtak and Merizo, on the south side of the island, 25% of the adults were dying of this weird disease.
Sometimes it looked like ALS. Some of the patients had symptoms like Parkinson's. Others had dementia like Alzheimer's. Some poor villagers had all three indications. [The National Institute of Health] had worked on this for 20 years. But what we brought to the table is — I'm actually not a medical doctor or a neurologist, I'm an ethnobotanist. So instead of sitting in a clinic with a white jacket and a stethoscope, we're out in the village talking to people, and we gained some really unique insights.
So tell me exactly what the findings were in Guam?
People in their diet have a high amount of the neurotoxin BMAA. This is produced by cyanobacteria, sometimes known as blue-green algae, but that's a misnomer because they're really not algae. They're a bacterium.
We found that in their diet of cycad flour and animals that eat cycad flour, they're getting large doses of BMAA. We were pretty astonished by the levels we saw in autopsy tissues in the villagers who died of the disease.
What does BMAA, this neurotoxin, actually do when it enters our systems?
Well, it's an amino acid. We have 20 amino acids that make up our normal proteins. This is not one of the 20. And it actually inserts itself for L-serine, an amino acid in neuroproteins— when it does that, it causes the neuroprotein to misfold and collapse.
What does that mean for Floridians that are periodically exposed to harmful algal blooms?
I saw on the television in 2016, what local people in Stewart, Florida called guacamole— [this] very viscous cyanobacteria fluent coming down the St. Lucie River. I jumped on a plane [and] came out. When I got here there were 11 dead manatees. We sampled and it was very high in this neurotoxin. The Corps of Engineers was also releasing water from Lake Okeechobee down the Caloosahatchee and it was there impacting all these people, clear up Port Charlotte almost down to Fort Myers and Naples. So, we wrote a paper on our findings, and the same thing happened in 2018. We were out again. This time, in Western Florida, there was a red tide that was occurring out to the ocean. And then this inland cyanobacterial bloom was hitting people. So, we've been working with many other partners, trying to encourage the Corps of Engineers to manage Lake Okeechobee, so these neurotoxic blooms do not get released down to the St. Lucie River and down the Caloosahatchee. And I'm really thrilled to hear that the Corps now is building this big reservoir south of Lake Okeechobee to release these waters into, so we're hoping that nobody again will be exposed to these neurotoxins.
And is a study that perhaps tracks where populations of high levels of ALS are appearing something you’re looking at?
Our colleagues, Dr. Elijah Stommel and his team at the Department of Neurology at Dartmouth have mapped ALS residences in New England. They find if you live next to a lake or estuary that has a high amount of cyanobacterial blooms that your likelihood of getting ALS goes up 25 fold. We were delighted that an unassociated group of epidemiologists from Arizona State did a study of environmental toxins in ALS and they find that the relationship between BMAA and ALS is the best supported linkage. There may be many other toxins in our environment that trigger these diseases, but we know for sure that that is one path. We do believe that if we can make sure that people are not exposed to cyanobacterial blooms, either through ingestion or fish, or breathing, that we can reduce at least some of the incidents of ALS and perhaps Alzheimer's disease.
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