It can accumulate in mollusks that feed on the dinoflagellates and cause food poisoning to humans

• A powerful neurotoxin produced by certain dinoflagellates found in red tides

Wikipedia Word definitions in Wikipedia
Saxitoxin ( STX ) is a potent neurotoxin and 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 ...

Wiktionary Word definitions in Wiktionary
n. A neurotoxin, produced by some dinoflagellates, that can accumulate in mollusks and cause subsequent food poisoning in humans

WordNet Word definitions in WordNet
n. a powerful neurotoxin produced by certain dinoflagellates found in red tides; it can accumulate in mollusks that feed on the dinoflagellates and cause food poisoning to humans