Dolphins show Alzheimer's-like brain changes due to toxins
Researchers just discovered that bottlenose dolphins stranded in Florida's Indian River Lagoon showed brain changes similar to Alzheimer's disease—think amyloid plaques and tau tangles, the same stuff seen in humans.
The culprit? Long-term exposure to environmental toxins, according to a 2025 study in Communications Biology.
Dolphins had high levels of neurotoxin during summer algal blooms
During summer algal blooms, dolphins had sky-high levels of a neurotoxin called 2,4-DAB—up to 2,900 times higher than normal.
This toxin comes from cyanobacteria and builds up through the food chain, which may contribute to the confusion and strandings scientists have observed.
Dolphins are like ocean health detectives
Dolphins are like ocean health detectives: if they're getting sick from these toxins, humans eating contaminated seafood could be at risk too.
The study highlights why we need more research on how pollution might affect our own brains down the line.