ABSTRACT
Ciguatera fish poisoning is a peculiar food poisoning which results from the consumption of any of a large variety of tropical and subtropical fish associated with coral reefs. The disease affects in excess of 25,000 persons annually. Ciguatera fish poisoning has long been reported to be of regional occurrence, being limited to definite regions of certain islands in tropical or subtropical zones of the world and, possibly, to narrow regions of those islands. The outbreaks of the disease are not seasonal but occur consistently throughout the year. Moreover, other investigators have cited the changing toxicity over the years. Further, it should be emphasized that the occurrence of ciguatera fish poisoning does not depend on the species of fish consumed. The same species in very close geographical proximity may be toxic in one area and nontoxic in another. In order to analyze the mechanisms of the outbreaks of such complex and discrepant disease, the food chain concept has been introduced. From observations of the ecological phenomena and those of food habits of fish in coral reefs, Randall (1) suggested that the causative agents of ciguatera fish poisoning may produce a benthic microorganism, most likely a bluegreen alga, that is a source of the toxin. Herbivorous fish consume the benthic organism that contains the toxin. These fish may then be consumed by larger carnivorous fish. Thus the toxin passes up the food chain to the human consumer. Later, Yasumoto and his coworkers (2) indeed found that a benthic microalga, Gambierdiscus toxicus, produces potent causative toxins involved in ciguatera fish poisoning. Thereafter, a number of investigators have isolated several causative agents of ciguatera fish poisoning from the viscera of toxic coral reef fish or from dinoflagellates in culture. Chemical structures of these toxins are polyethers such as ciguatoxins and maitotoxin. Among them, lipid-soluble ciguatoxin and water-soluble maitotoxin are the most potent marine toxins known.
