- Introduction -

Tetrodotoxin (TTX) is a potent neurotoxin commonly found in puffer fish.
It was named by Toshizumi Tahara in the late 1880s after the order of Tetraodontiformes (puffer fish), where it was first observed. Besides the
puffer fish, TTX has also been found in a wide range of marine species
such as, the blue ringed octopus, California Newt, Ocean sunfish, porcupine
fish and the Costa Rican frogs amongst others.

Through the study of cultured puffer fish, it was discovered that TTX was not metabolically produced within the fish. Instead, it is synthesized by several bacterial species, including strains of the family Vibrionaceae and Pseudomonas sp.

TTX acts on the central and peripheral nervous system by blocking the Sodium ion channels vital for cellular signaling pathways (e.g. transmission of impulses and maintenance of cell functions), eventually leading to paralysis and even death.

The comparative toxicity was summarized by William H. Light who
said, “[W]eight for weight, Tetrodotoxin is ten times as deadly as the
venom of many-banded krait of Southeast Asia. It is 10 to 100 times
as lethal as black widow spider venom (depending upon the species)
and more than 10,000 times deadlier than cyanide.” A small dose of
1-2mg of purified TTX is lethal.

Back to Top