Lisbet Díaz Asencio, Donaida Chamero Lago, Miguel Gómez Batista, Gabriel Rojas Abrahantes, (Centro de Estudios Ambientales de Cienfuegos, Cuba); Rachel J. Clausing (International Atomic Energy Agency, USA; University of California Los Angeles, USA); Mark Vandersea, R. Wayne Litaker (National Centers for Coastal Ocean Science, USA); Joan I. Hernández Albernas (Refugio de Fauna Cayo Santa María, Cuba); Nicolas Chomérat (Coastal Research Unit, France); Patricia Tester (Ocean Tester, USA); Jorge Diogène (Marine Environmental Monitoring, Spain); Carlos M. Alonso Hernández (Centro de Estudios Ambientales de Cienfuegos, Cuba; Intergovernmental Oceanographic Commission of UNESCO, Denmark); Marie Yasmine Dechraoui Bottein (International Atomic Energy Agency, Mónaco; Intergovernmental Oceanographic Commission of UNESCO, Denmark)
Abstract: In Cuba, ciguatera poisoning associated with fish consumption is the most commonly occurring non-bacterial seafood-borne illness. Risk management through fish market regulation has existed in Cuba for decades and consists of bans on selected species above a certain weight; however, the actual occurrence of ciguatoxins (CTXs) in seafood has never been verified. From this food safety risk management perspective, a study site locally known to be at risk for ciguatera was selected. Analysis of the epiphytic dinoflagellate community identified the microalga Gambierdiscus. Gambierdiscus species included six of the seven species known to be present in Cuba (G. caribaeus, G. belizeanus, G. carpenteri, G. carolinianus, G. silvae, and F. ruetzleri). CTX-like activity in invertebrates, herbivorous and carnivorous fishes were analyzed with a radioligand receptor-binding assay and, for selected samples, with the N2A cell cytotoxicity assay. CTX activity was found in 80% of the organisms sampled, with toxin values ranging from 2 to 8 ng CTX3C equivalents g1 tissue. Data analysis further confirmed CTXs trophic magnification. This study constitutes the first finding of CTX-like activity in marine organisms in Cuba and in herbivorous fish in the Caribbean. Elucidating the structure–activity relationship and toxicology of CTX from the Caribbean is needed before conclusions may be drawn about risk exposure in Cuba and the wider Caribbean.
Key words: Caribbean, ciguatoxicity, qPCR, trophic transfer, fish, food safety, food security, science-based management, foodborne disease