Loeffler, Christopher (2021) Ciguatoxins and Ciguatera Poisoning: forecasting risk, method development, and applied outbreak response. [Tesi di dottorato]

Anteprima

Testo Loeffler_Christopher_34.pdf Download (5MB) | Anteprima

Abstract

Seafood is the most traded food commodity worldwide, providing nearly 20% of the animal protein intake for more than 3.3 billion people; and nearly 40% of total fisheries and aquaculture production are traded internationally every year. Ciguatera poisoning (CP) is a prevalent food-related health risk, caused by the consumption of seafood contaminated with ciguatoxins (CTXs). CTXs are classified as a human health hazard and within the European Union’s (EU) commercial jurisdiction, products containing CTXs must not be placed on the market. The processes for pre-market controls for CTX contaminant analysis exist but are seldom in place due to several factors including the complexity of CTX analysis and the sporadic nature of CTX contamination in seafood products. Several studies are described herein that target (1) prediction, (2) detection, and (3) outbreak response for CP. To investigate if a priori predictors for CP can be accurate, a hyperendemic region for CP was investigated for potential CTX predictors using two locations dissimilar for their environmental conditions. The CTX content measured in 113 fish was found to be distinct by location providing evidence that it may be possible to predict CP in certain situations. To improve an in vitro Neuro-2a cell-based assay method utilized for CTX detection a new cell line modification method was developed and described that resulted in an enhancement in toxin detection sensitivity over the standard method by 1.3-2.6x, depending on the target compound. Using the newly developed method, 45 fish related to a major CP outbreak that occurred in Germany were tested. All fillet portions measured by the assay had CTX contamination found to exceed the EU guidance for CTXs in seafood products and using LC-MS/MS the CTX3C-group was identified. Furthermore, using DNA-barcoding the commercial fish product was authenticated and found to be mislabeled by species. The works presented here can be applied in existing food safety laboratories for investigating CTXs to aid method development, CTX detection, and as a first step towards identifying reliable predictors to prevent CTXs from reaching the market.

Downloads

Actions (login required)

Modifica documento