NATURALLY-OCCURRING SEAFOOD TOXINS

Incidents of illness reported to the Centers for Disease Control (CDC) in the period 1978-1987 were limited to ciguatera, scombroid fish poisoning (SFP), and paralytic shellfish poisoning (PSP). Natural intoxications are both highly regional and species associated, and toxins are present in seafood at the time of capture. Ciguatera is a sometimes severe disease caused by consuming certain species Of fish, usually island or reef, from tropical, subtropical, and other (temperate) waters, and was responsible for about half of all reported outbreaks to the CDC. Treatments are largely supportive, and mortality is usually low. Controls based on regulation of fishing or marketing of dangerous species, supported by testing suspect fish and educating consumers, sports fishers and health professionals, are recommended. SFP caused nearly the same number of outbreaks as ciguatera, but was much more widespread. Tuna, mahimahi and bluefish are implicated as the major cause of SFP. The disease is generally mild and self-resolving, and symptoms can often be ameliorated by certain antihistamine drugs. Because the histamine poisoning is produced due to improper temperature control after the fish is caught, the disease can be prevented by rapid cooling and holding fish at low temperature(s) before cooking, as well as by not leaving the fish out too long when serving it under inadequate temperature control. A Hazard Analysis Critical Control Point-based system, and the education of subsistence and recreational/commercial fishers and cooks/servers may control this poisoning. Paralytic shellfish poisoning was reported to the CDC as a minor cause of illness, with only two deaths. Although "other" natural seafood intoxications (e.g., puffer fish poisoning, and neurotoxic, diarrhetic and amnesic shellfish poisoning) have not been widely reported in U.S. consumers, the potential for their occurrence either from domestic or imported seafoods from imports is real. Increased vigilance concerning imported product, testing for these "other" toxins, and procedures to deal with outbreaks are needed.