Alzheimer's plaques found in dolphins' brains hint at toxin risk

In a new study, researchers revealed the discovery of beta-amyloid plaques in the brains of stranded dolphins, the same plaques associated with Alzheimer's disease in humans. The finding builds upon existing evidence of an association between toxic cyanobacterial blooms and Alzheimer's risk, though there's still not enough evidence to determine whether this toxin puts humans at risk.

Past research identified a link between dietary exposure to BMAA, a cyanobacterial toxin, and the development of both neurofibrillary tangles and beta-amyloid plaques. That link was only found in lab animals like mice, however. This newest study highlights a similar discovery in wild dolphins that had been stranded in the Gulf and Massachusetts.

Coastal waters around areas like Florida have suffered from a growing number of cyanobacterial blooms in recent years; they're the result of warming waters and often last longer than past blooms. This uptick in blooms increases marine life exposure to the toxins produced by the cyanobacteria, putting their health at risk.

Of key importance here is the discovery of the aforementioned BMAA cyanobacterial toxin in the brains of these deceased dolphins, which were also found to contain beta-amyloid plaques associated with Alzheimer's disease in humans. It's unclear whether the dolphins experienced cognitive changes that led to them becoming stranded on these beaches.

A big question remains unanswered at this time: does exposure to cyanobacteria toxins increase the risk of developing Alzheimer's disease in humans? Though science can't yet say for sure, this growing body of evidence hints at the need for humans to take preventative measures in regards to exposure until more info is known.