More than a dozen dolphins stranded on the beaches of Florida and Massachusetts are found with brains filled with amyloid plaques, a hallmark of Alzheimer's disease.
Scientists who made the discovery think they can warn us everything: along with Alzheimer-like plaques, the team also finds the BMAA ecological toxin.
Made from blue-green blooming algae, this neurotoxin is easily trapped in the ocean food network, and chronic nutritional exposure has long been thought to be a cause of neurological disease including Alzheimer's, Parkinson's and Amyotrophic Lateral Sclerosis (ALS)
The presence of both BMAA and amyloid plaques in the 13 twisted dolphins adds even more weight to this hypothesis.
"Dolphins are excellent species for toxic exposures in the marine environment."
"With increasing frequency and duration of cyanobacterial flowering in coastal waters, dolphins can provide an early warning of toxic exposures that may affect human health."
They can also be a good animal model for how BMAA can cause Alzheimer's disease. In 201
Meanwhile, the dolphins inhabiting the Florida coastal waters are also often exposed to recurrent harmful algae (HABs). This may be a coincidence, but experiments have shown that chronic exposure to BMAA can cause neurodegenerative changes in both humans and non-human primates. "Acute and chronic exposure to such toxins can be harmful to humans and animals, leading to respiratory diseases, severe dermatitis, mucosal damage, cancer, organ failure and death," the authors write. these HABs are becoming more and more frequent, and the authors worry that dolphins will accumulate even more BMAA as a result, "both by exposing HABs and by swallowing prey before being exposed to cyanotoxin." such beings may very well be our first indication of bad ecological conditions and while it is still unclear whether these colors directly lead to Alzheimer's disease in dolphins or humans, researchers argue that this is a risk that should not we accept. "The $ 64,000 issue is whether these marine mammals have had cognitive deficits and disorientation that led to their voyage," says co-author Paul Allen Cox, an ethnobotan of the Jackson Hole Brain Laboratory.
"While further research does not clarify this issue, people should take simple steps to avoid exposure to cyanobacteria."
This study was published in PLOS ONE .