Ciguatera Fish Poisoning (CFP) is a common form of seafood poisoning, affecting tens of thousands of people worldwide. People who consume reef-dwelling fish such as grouper, snapper, barracuda, hogfish, and triggerfish are potentially at risk. Although CFP is primarily a concern in tropical and sub-tropical coastal regions, the export of fish from these areas to markets in other regions creates a risk to fish consumers worldwide. One of the reasons why so many people are afflicted with CFP is because no simple screening method currently exists, hindering efforts to monitor for CFP outbreaks and protect people from exposure to toxic fish.
CFP is caused by the consumption of seafood (primarily reef fish) contaminated with ciguatoxins. Ciguatoxins are heat-stable and therefore persist in the fish tissue even after being cooked.
Gambiertoxins, precursors of ciguatoxins produced by the (sub)tropical benthic dinoflagellate genus Gambierdiscus, enter reef food webs when herbivores and detritivores consume Gambierdiscus directly or indirectly by grazing on macroalgae. These precursor molecules are transferred to higher trophic levels by bioaccumulation, bioconversion and biomagnification until they reach predatory finfish species that are targeted in many commercial and recreational fisheries. When people subsequently consume the contaminated fish, they are exposed to the toxins, thereby experiencing CFP.
Common CFP symptoms include gastrointestinal problems like abdominal cramps, diarrhea, nausea, and vomiting followed by neurological symptoms. Headaches, muscle aches, and numbness are common; other symptoms may include strange sensations, such as the feeling of loose teeth, confusion between hot and cold temperatures, or a metallic taste in the mouth. Symptoms may persist for weeks or months. Death is rare, and usually associated with the consumption of whole fish, in which organs where toxins accumulate in higher concentrations are ingested.