Shellfish Toxicity

Excerpt

Oysters, clams, mussels, scallops, and, rarely, crustaceans, gastropods, and some fish may be contaminated by dinoflagellate or cyanobacteria toxins. Consumption of these marine food sources can cause poisoning, producing neurologic and gastrointestinal symptoms. The action sites of marine toxins include ion channels, kainate receptors, and protein phosphatases, which are crucial to nerve and muscle function. Disruption of these molecules' functions causes the symptoms observed in patients with shellfish toxicity.

Shellfish poisoning may be classified into 4 clinical syndromes, depending on the specific etiology and clinical presentation: paralytic shellfish poisoning (PSP), neurotoxic shellfish poisoning (NSP), amnesic shellfish poisoning (ASP), and diarrheic shellfish poisoning (DSP). PSP is associated with saxitoxins. NSP is produced by brevetoxin. ASP is due to domoic acid ingestion. DSP is caused by okadaic acid. These toxins and their associated illnesses are related to harmful algal blooms.