• Subtropical and tropical fish can become ciguatoxic.coral reef image by Christian Schoettler from Fotolia.com
  
  Ciguatera is a toxin produced by Gambierdiscus toxicus, a microalgae eaten by fish. The concentration of cigua toxin increases further up the fish food chain. Outbreaks of Ciguatera can occur when algal blooms of Gambierdixcus toxicus grow due to decay of corals damaged by adverse weather.
  
  

Fish Implicated In Ciguatera Poisoning

• Fish that eat other fish can accumulate ciguatoxin.barracuda image by Davide Rigatti from Fotolia.com
  
  Ciguatoxins have been found in barracuda, black grouper, blackfin snapper, cubera snapper, dog snapper, greater amberjack, hogfish, horse-eye jack, king mackerel, and yellowfin grouper. (See reference one) The World Health Organization (WHO) cannot supply an exhaustive list as ciguatoxin can be found in different areas and different fish species over time.
  
  Over 300 species of fish have been known to cause ciguatoxin poisoning. (See reference two) Symptoms occur from 10 minutes to 24 hours after ingestion, initially presenting as gastrointestinal upset and vomiting.
  
  The toxin can cause tingling and numbness of the mouth and extremities, headache, muscle cramping, vertigo and perspiration.
  
  Hallucinations can occur, along with a sense of temperature reversal (hot objects feel cold and cold objects feel warm).
  
  

Ciguatera Can Be Present Across Wide Geographical Areas

• Ingesting fish is the source of Ciguatera poisoning in humans.coral reef 20 image by Christian Schoettler from Fotolia.com
  
  Ciguatera is caused by ingesting fish that have eaten Gambierdiscus toxicus or by eating fish that have eaten ciguatoxic fish. To negate the risk of ciguatera poisoning, one must avoid eating fish entirely from the Pacific and Indian oceans and the tropical Caribbean where the microalgae may be growing. (See Reference 2) However, if one wishes to eat fish from those areas, by following WHO guidelines, the risk can be reduced.
  
  

Reducing The Risk of Ciguatera

• Cooking does not destroy Ciguatoxin.baking fish image by Wouter Tolenaars from Fotolia.com
  
  Ciguatoxin is very heat stable. Cooking will not destroy the toxin. Since so many marine species have been implicated in Ciguatera, it is hard to avoid all potential sources. The WHO recommends talking to local fishermen to find out which reefs or marine locations harbor fish which may not be safe to eat. If no information is available, the WHO recommends avoiding large reef fish, as by virtue of their age they may have accumulated more toxins than smaller fish.