ASSESSMENT OF A RAPID ENZYME IMMUNOASSAY STICK TEST FOR THE DETECTION OF CIGUATOXIN AND RELATED POLYETHER TOXINS IN FISH TISSUES

Abstract

We have developed a rapid and simple enzyme immunoassay stick test for ciguatoxin and related polyether toxins in fish tissues. This assay can be used to examine clinically implicated fishes from ciguatera poisonings, corresponding catches of fishes obtained in the same vicinity as those clinically implicated, non-toxic consumed fishes, and nearshore reef fishes. With this assay, 14 clinically documented fishes gave a mean and standard deviation (x ± S.D.) of 3.1 ± 0.7. The corresponding catches of fishes from areas implicated in ciguatera poisonings showed the following percentages of toxicity for Ctenochaetus strigosus: Hawaii Island, 45.0%; Kauai, 80.6%; and Oahu, 42.5%. Sixty non-toxic consumed fishes gave a x ± S.D. value of 1.2 ± 0.5, and Thunnus thynnus, a pelagic fish never implicated in ciguatera poisoning, gave a x ± S.D. value of l.1 ± 0.8. All of the clinically implicated fishes were in the borderline to positive value ranges with the stick test. Associated with the high incidence of toxicity of C. strigosus from Kauai, Gambierdiscus toxicus was found in the gut of all 93 fish samples examined. The stick enzyme immunoassay has proven to be simple, rapid, sensitive, and specific.