The toxin causing ciguatera. It is produced by dinoflagellates which are then eaten by small fish. As these fish get eaten by larger ones progressing up the food chain the toxin becomes concentrated in the flesh (and liver) and can then intoxicate humans. In humans the toxin is not destroyed and so further ingestion of ciguatoxin causes a cumulative effect.
Tropical fish poisoning occurring some 1-24hrs after ingestion of fish containing ciguatoxin. Symptoms are diverse and include (in approximate frequency): lassitude, muscle pains, burning of skin when cold objects are touched, itching, joint pains, paraesthesiae (especially hands, feet and lips), headache and diarrhoea, as well as manyother less common symptoms. Ciguatera is a major world health problem in Countries relying on reef fish as the main source of protein and has caused many deaths. Neurological signs and symptoms may last for months, even years.... ciguatera
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