Compass- word of a TEST KIT.
The ciguatera threat begins when reef fish ingest the toxin-bearing dinoflagellates called Gambierdiscus toxicus microscopic, single-celled, free-swimming marine
organisms which have attached themselves to the coral-dwelling marine
algae which is the fishes' food. Larger, carnivorous fish eat the reef fish, and are in turn eaten by even larger predatory fish, which may in turn be eaten by man. Although hosts to the toxins, the fish themselves are not ill.
Ecological conditions in some localities support a continuous population of dinoflagellates, which then produce more ciguatoxin-bearing fish than other areas. Ecological disturbances to a reef, such as storm surges or careless development, can also cause the toxic organisms to spread rapidly.
In the Caribbean, ciguatera is most prevalent in the islands north of Martinique
. A paper by David Olsen, David Nellis and Richard Wood published in the Marine Fisheries Review (Vol. 46, No. 1) pinpointed three primary centers of the toxin: one near Redonda between Antigua
and Montserrat, one between the Saba
Bank and the Anguilla
Bank, and a third along the narrow shelf south of Norman and Peter Islands. Several St. Thomas, USVI markets no longer sell local fish and import
all fish products sold, except for a very narrow range of species caught in specific "safe" locales. (John Smith says, "Anyone who has spent any time in the Virgin Islands
is well aware that giving someone a kingfish caught on the south shore is not considered an act of kindness.")
Big Bad Fish
Because the toxin accumulates in the body of the fish, you should avoid eating large specimens of potentially ciguatoxic fish such as barracuda and kingfish that may carry high concentrations, even in areas where ciguatera is rare. St. Vincent & the Grenadines, for example, has had only one confirmed incidence of ciguatera poisoning, but it was devastating. A report by Chief Fisheries Officer Kerwin Morris relates that on the late afternoon of November 23, 1985, in the village of Owia, people "started pouring into the clinic in search of relief from vomiting, diarrhea and abdominal pains." By the next morning, over a hundred villagers were hospitalized in nearby Georgetown
It was discovered that some 120 people had eaten a noonday meal that included meat from the same 30-pound barracuda. Some affected individuals had merely drunk the broth in which a piece of fish had been boiled. An undetermined number of small animals
including cats, dogs
and chickens died after eating parts
of the fish which had been thrown away.
According to the Caribbean Fisheries Research
and Management Project
(CFRAMP), affected fish looks, smells and tastes normal. Freezing, drying, marinating, salting or cooking
the fish does not destroy the poison. The freshness of the fish has no bearing on its toxicity.
So what to do, especially when you enjoy eating fish?
Exercise extreme caution when eating fish in high-risk areas (i.e. north of Martinique).
Avoid those fishes that are most often toxic. Potentially ciguatoxic fish include (but are not limited to) barracuda, greater amberjack, kingfish, cavalli, mutton and dog snapper, sharks, large grouper, hogfish and moray eel. Plant-, plankton- and coral-eating fish tend not to be toxic, and pelagic species such as dolphin (dorado) and tuna are rarely implicated.
Always ask the locals what they eat and don't eat. (Remember that common names often differ from one location to another.)
Choose small specimens of a species, as they are usually less likely to be toxic than large ones.
Test the fish you catch with a test kit
Always clean a fish thoroughly before cooking
it. The poison is usually concentrated in the head
, organs and roe.
If you experience any symptoms of ciguatera, seek medical
attention immediately. There is no antidote, but symptoms can be alleviated.
Information from Compass
correspondents Clifford Lee-Juillerat and John Smith, and from the Caribbean Fisheries Research
and Management Project
, Ciguatera by Dr. Yoshitsugi Hokama, and the Marine Fisheries Review was used in preparing this report.
Ciguatera Test Kit
Folklore says you can test a piece of fish for ciguatera by seeing if a silver coin placed on it turns black, or if a sweet potato boiled with it changes color. These tests have proven to be unreliable.
A faculty member
at the University of Hawaii
, Dr. Yoshitsugi Hokama, has developed a scientific test kit to determine whether or not that fish you just caught is really safe to eat.
The kit, which California
sailing magazine Latitude 38 says "works like one of those pregnancy kits you buy in the drug store", has only one drawback the test takes an hour. Can you wait that long before you toss those succulent kingfish steaks onto the barbecue grill
For information on ordering kits, contact Oceanit Test Systems. 1100 Alakea Street, Honolulu, Hawaii
96813, USA. Tel (808) 531-3017,
fax (808) 531-3177, E-mail firstname.lastname@example.org