Predictive score and probability of CTX-like toxicity in fish samples from the official control of ciguatera in the Canary Islands

This research identifies factors associated with he contamination by cigualoxins ((TXs) in a population of fish and proposes a predictive score of-the presence of (TX like toxicity in amberjack samples from the official control program of ciguatera in the Canary Islands of the Directorate-General (DG) Fisheries (Canary Government). Out of the 970 samples of fish studied, 177 (18.2%) samples showed CTX-lilw toxicity. The fish were classified according to he species, amberjack (Seriulu dumerili and S. rivuliuna) (n 793), dusky grouper (Epinephelus marginatus) (n 145) and wahoo (Acanthocybium solandri) (n 32). The data were separated by species category and statistically examined, resulting in 137 (17.3%) amberjack and 39 (26.9%) grouper samples showing CTX-like toxicity; regarding wahoo species, only 1 toxic sample (3.1%) was found. According to fishing location the contamination rates suggested grouping the islands in four clusters; namely: {EI Hierro: HI; La Gomera: LG; La Palma: LP), {Gran Canaria: GC; Tenerife: TE1, {Fuerteventura: Fl.{} and {Lanzarote: L/1. For the amberjack species, the multivariate logistic regression showed the factors that maintained independent association with the outcome, which were the warm season (OR 3.617; 95% CI 1.249-10.474), the weight (per kg, 1.102; 95% CI 1.069-1.136) and the island of fish catching. A prediction score was obtained for the probability of contamination by CD( in amberjack fish samples. The area under de curve (AUC) obtained using the validation data was 0.747 (95%CI 0.662-0.833). Regarding grouper species, the island of fishing was the only factor that showed significant differences associated with the presence of CTX-like toxicity. We provide herein data for a better management and prediction of ciguatera in the Canary Islands, suggesting a review of the minimum limits of fish weight established by the Canary Government for the control program. (C) 2019 Elsevier B.V. All rights reserved.