Saxitoxin

Saxitoxin (STX) is a potent neurotoxin, the best-known paralytic shellfish toxin (PST). Ingestion of saxitoxin (usually by consumption of shellfish contaminated by toxic algal blooms) is responsible for the human illness known as paralytic shellfish poisoning (PSP).

The term saxitoxin originates from the genus name of the butter clam (Saxidomus giganteus) from which it was first isolated. But the term saxitoxin can also refer to the entire suite of more than 50 structurally related neurotoxins (known collectively as "saxitoxins") produced by algae and cyanobacteria which includes saxitoxin itself (STX), neosaxitoxin (NSTX), gonyautoxins (GTX) and decarbamoylsaxitoxin (dcSTX).

Saxitoxin has a large environmental and economic impact, as its presence in bivalve shellfish such as mussels, clams, oysters and scallops frequently leads to bans on commercial and recreational shellfish harvesting in many temperate coastal waters around the world including northeastern and western United States, western Europe, east Asia, Australia, New Zealand and South Africa. In the United States, paralytic shellfish poisoning has occurred in California, Oregon, Washington, Alaska, and New England.