Paralytic shellfish poisoning: a review.

Paralytic shellfish poisoning (PSP) in man results from the consumption of mussels, clams, and oysters that have fed on toxic dinoflagellates. Motile, marine protozoa of the dinoflagellate group often produce "blooms," i.e., red tides, which color the sea. Not all genera or species are toxic to fish and mammals, nor are the toxic principles the same in all poisonous protozoa. At least 5 of the group are known to cause poisonings in man. Shellfish poisonings other than PSP are also recognized. The PSP toxin, saxitoxin, is concentrated in the viscera and occasionally in the mantle and syphon of marine bivalves. Cooking does not completely destroy the low molecular weight poisonous factor. Reported mortality ranges from 8.5 to 23.2%. The disease is of significant public health concern in some localities of the world from May to November.