Toxic Algae Blooms Linked To Alzheimer’s-Like Brain Changes In Dolphins

Florida’s toxic red algae bloom has become the poster child for what can happen to coastal waters when water ways are not properly managed and researchers are just starting to see the devastating results caused by it.

A new study, published in the journal PLOS ONE, found that a majority of dolphins washed up on the United States east coast had high level of toxins in their brains that also were accompanied by signs of neurodegeneration , similar to what is seen in humans whom have Alzheimer’s disease.

Toxic algal blooms contain a neurotoxin called B-methylamino-L-alanine (BMAA), which has previously been linked to B-amyloid, a protein involved in Alzheimer’s, in nonhuman primates. The neurotoxin has also been spotted in brains of people whom suffered through Alzeimer’s and ALS, which is a neurodegenerative condition which is also known as Lou Gehrig’s disease.

The researchers from the University of Miami looked at 14 dolphins that had been stranded. 13 of those contained the neurotoxin BMAA while the marine mammals also showed signs of Alzheimer’s-like degeneration.

The researchers note that Florida’s dolphins are often exposed to harmful algal blooms both directly and via eating creatures that have been exposed to the algae’s toxins. Half of the dolphins tested were found on Florida’s coastline at sites known for experiencing recurring algal blooms. The remaining seven dolphins were found washed up in Massachusetts. The animals were a mixture of bottlenose and common dolphins.

The quantity of BMAA found in the dolphins’ brains was 1.4 times greater than levels observed in the brains of human patients with Alzheimer’s and ALS. Even more alarming is that the Florida dolphins contained three times as much BMAA which may be directly linked to the algae blooms that have been causing problems on the Sunshine States coastline.

While the findings do not imply that BMAA causes neurodegeneration, it may mean that there may be a link between the two. The researchers point out that as our climate continues to warm, the issue could continue to grow as toxic algal blooms are becoming more frequent and lasting longer. What’s more, the results indicate that humans exposed to BMAA, such as those living near water, could suffer a similar fate.

“This isn’t animals being fed a certain dose over a certain amount of time. It’s naturalistic exposure,” lead author David Davis told the Miami Herald. “If you have these … dolphins feeding in the same marine food web as humans, potentially eating the same things as humans, that’s why we say it serves as a sentinel.”

As more research pours in regarding the issue, it will reveal just how impactful and how big of a problem this will be as our climate continues to change.