Ciguatoxins originate from marine algae, such as Gambierdiscus spp., enter the food web through fish, and pass to humans. To improve detection methods and better understand the production of ciguatoxins, we used liquid chromatography‒mass spectrometry (LC‒MS) to quantify the toxins isolated from laboratory algal cultures. We confirmed the presence of six known Pacific ciguatoxins and detected several new cogeners (related chemical substances).
Why We Care
Ciguatera fish poisoning (CFP) is the world’s most common food-borne disease related to consuming contaminated finfish, with more than 50,000 cases reported each year. Ciguatera fish poisoning causes gastrointestinal, cardiovascular, and neurological disorders. The toxin is not destroyed by cooking or other preparation techniques. Symptoms can be treated, but there is no antidote. Marine algae that produce ciguatoxins inhabit tropical and subtropical coral reef regions, such as Florida, Hawaii, the Caribbean, and South Pacific islands. The United States imports more than 80 percent of its seafood. Ciguatera disease cases in the continental United States are thought to be related to imported seafood from the tropics. Chemical structures of ciguatoxins vary with their area of origin and include Caribbean, Indian, and Pacific ciguatoxins. There are no algal ciguatoxin standards commercially available as they are present at low but biologically relevant concentrations in seafood and algae.
What We Did
We used LC‒MS to analyze and quantify ciguatoxins in fractions isolated from laboratory algal cultures. We are collaborating with Laboratoire des Microalgues Toxiques, Institut Louis Malardé, French Polynesia, to analyze algal cultures. The data are helping us improve ciguatoxin detection and confirmation methods as well as understand toxin production.
What We Found
We confirmed six known Pacific ciguatoxins and detected several other new ciguatoxin congeners.
We have grown additional ciguatoxin cultures and isolated additional quantities of individual known toxin congeners. We are examining the purity of the major algal Pacific ciguatoxins isolated and looking for other new toxins using LC‒MS. We will analyze seafood collected and isolated in French Polynesia to determine if ciguatoxins from a known or unknown category are present, which could indicate additional ciguatoxin production mechanisms.