Domoic acid

Domoic acid, also called Amnesic Shellfish Poison (ASP) is an acid sometimes found in algal blooms (of phytoplankton). The acid can bio accumulate in marine organisms that feed on plankton, such as shellfish, anchovies and sardines. In mammals, including humans, it acts as a powerful neurotoxin. In humans it can cause short term memory loss, brain damage and death in severe cases.

Although algal blooms may be pink, orange, blue, yellow, green, brown, violet, or red, depending upon the concentration of algae, the name Red tide is associated with the phenomenon of such algal blooms.