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BBB - Gempylotoxin

Bad Bug Book:
Foodborne Pathogenic Microorganisms and Natural Toxins Handbook

A new version of the Bad Bug Book was released in 2012, below is a previous version.

  1. Name of the Toxin: 


  2. Nature of Acute Disease:  

    Gempylotoxism or Gempylid Fish Poisoning or Keriorrhea (Keriorrhoea)

    FDA Statement on Consumption of Escolar and Oilfish: "There are naturally occurring toxins in some species that do not involve marine algae. Escolar (Scientific Name Lepidocybium flavobrunneum), and its relative Oilfish or Cocco (Scientific Name Ruvettus pretiosus) contains a strong purgative oil, that when consumed can cause diarrhea known as Gempylid Fish Poisoning or Gempylotoxism. FDA advises against the sale of the fish in intrastate/interstate commerce, and requests that seafood manufacturers/processors should inform potential buyers/sellers, etc. of the purgative effect associated with the consumption of these fish.

    The FDA district offices have been informed to report any illnesses associated with the consumption of these fish to CFSAN.

    If there are further questions regarding escolar and relative species, please contact the Division of Seafood Safety, Office of Food Safety, CFSAN, 301-436-2300."

    (Based on Health Hazard Evaluation No. 2841, Health Hazard Evaluation Board, CFSAN, FDA, 1992.)

  3. Nature of Disease:

    An outbreak of gastrointestinal illness associated with the consumption of escolar fish, K Yohannes, CB Dalton, L Halliday, LE Unicomb, M Kirk, Commun Dis Intell 2002; 26:441-445.

    Abstract: An outbreak of gastrointestinal illness occurred amongst attendees of a conference lunch in the Hunter area, New South Wales, in October 2001. A distinctive symptom reported by many ill persons was the presence of oily diarrhoea. The Hunter Public Health Unit investigated the outbreak by conducting a telephone interview of the cohort of conference attendees using a standard questionnaire. Twenty persons out of 44 attendees (46%) became ill following the conference. The median incubation period was 2.5 hours (range 1-90 hours). The most common symptoms reported were; diarrhoea (80%) < 38 per cent of these reported oily diarrhoea; abdominal cramps (50%); nausea (45%); headache (35%) and vomiting (25%). For analyses, a case was defined as a person who developed oily diarrhea, or diarrhoea within 48 hours, or had at least two other symptoms of gastroenteritis within 6 hours, of the conference lunch. Seventeen persons had symptoms that met the case definition. None of the foods or beverages consumed were significantly associated with illness, however, all cases had consumed fish and none of those who did not eat fish (4 persons) became ill. Moreover, only 'fish' or 'potato chips' could explain a significant proportion of the illness. Analysis of the oil composition of the fish consumed was consistent with the known profile of the species marketed as 'escolar'. Among those who consumed fish the following potential risk factors did not have a significant association with the illness: Body Mass Index, age, health status and the amount of fish consumed. We concluded that consumption of fish within the marketing group escolar can cause severe abdominal cramping, nausea and vomiting, in addition to incontinent diarrhoea.
    Full report

  4. Diagnosis of Human Illness: 

    See Nature of Disease (above)

    Additionally, there has been a report of scombrotoxin poisoning (also known as scombroid poisoning and histamine fish poisoning) associated with the consumption of Escolar fish (Lepidocybium flavobrunneum): Feldman KA, Werner SB, Cronan S, Hernandez M, Horvath AR, Lea CS. A large outbreak of scombroid fish poisoning associated with eating escolar fish (Lepidocybium flavobrunneum). Epidemiol Infect. Feb 2005;133(1):29-33.

    Summary: In August 2003, an outbreak of scombroid fish poisoning occurred at a retreat centre in California, USA. In a retrospective cohort study, 42 (75%) of the 56 dinner attendees who ate escolar fish (Lepidocybium flavobrunneum) met the case definition. Individuals who ate at least 2 oz of fish were 1.5 times more likely to develop symptoms than those who ate less (relative risk 1.5, 95% confidence interval 0.9–2.6), and to develop more symptoms (median 7 vs. 3 symptoms, P=0.03). Patients who took medicine had a longer duration of symptoms than those who did not (median 4 vs. 1.5 h, P=0.05), and experienced a greater number of symptoms (median 8 vs. 3 symptoms, P=0.0002). Samples of fish contained markedly elevated histamine levels (from 2000 to 3800 ppm). This is one of the largest reported outbreaks of scombroid fish poisoning in the United States and was associated with a rare vehicle for scombroid fish poisoning, escolar.

  5. Associated Foods: 

    Symptoms are associated with the ingestion of Escolar (Lepidocybium flavobrunneum) or Oilfish (Ruvettus pretiosus). Other species (including Butterfish, Rudderfish, Cod, and Taiwanese Seabass have been implicated, but these may be due to species substitution or misbranding.

    Images and other information from the Regulatory Fish Encyclopedia:

    Photos of Commercial Product and Packaging

    Escolar label

    Escolar packaging

  6. Relative Frequency of Disease: 

    Gempylotoxin poisoning reports are sporadatic.

  7. Course of Disease and Complications: 

    See Nature of Disease, above.

  8. Target Populations: 

    Anyone ingesting these fish species may be affected.

  9. Food Analysis: 

    The oils contain of high levels of indigesible wax esters.

    Review Article on Fish-induced Keriorrhea: Ling, K. H.; Nichols, P. D.; But, P. P. H. (2009). "Fish-induced Keriorrhea". In: Taylor, S. L. (Ed.), Advances in Food and Nutrition Research, 57: 1–52. Academic Press, San Diego.

    "Rapid detection of oilfish and escolar in fish steaks: A tool to prevent keriorrhea episodes", Ka Ho Ling, Chun Wai Cheung, Sau Wan Cheng, Ling Cheng, Song-Lin Li, Peter D. Nichols, Robert D. Ward, Alastair Graham, Paul Pui-Hay But, Food Chemistry, 110 (2008), 538-546.

    "Unusually high levels of non-saponifiable lipids in the fishes escolar and rudderfish: Identification by gas and thin-layer chromatography", PD Nichols, BD Mooney, NG Elliott, Journal of Chromatography A, 936 (2001) 183-191 [CSIRO Marine Research, GPO Box 1538, Hobart, Tasmania 7000, Australia.] | PubMed

    "Keriorrhoea - the passage of oil per rectum - after ingestion of marine wax esters", Berman P, Harley EH, Spark AA, S. Afr. Med. J. 1981 May 23; 59(22), 791-2 | PubMed

    "B.W. Halstead, "Poisonous and Venomous Marine Animals of the World", Vol. II, U.S. Government Printing Office, Washington, DC, 1967

    "The lipids of Ruvettus pretiosus muscle and liver", Nevenzel JC, Rodegker W, Mead JF, Biochemistry. 1965 Aug; 4(8):1589-94 | PubMed

    [Wax components of escolar (Lepidocybium flavobrunneum) and its application to base of medicine and cosmetics], Ukishima Y, Masui T, Matsubara S, Goto R, Okada S, Tsuji K, Kosuge T., Yakugaku Zasshi. 1987 Nov; 107(11):883-90 [Article in Japanese] | PubMed

    Abstract:    Escolar (Lepidocybium flavobrunneum) belonging to family Gempylidae are caught by a rope stretching fishing. The sale of escolars for food, however, is prohibited in Japan because their muscles are rich in wax which may cause a food poisoning. In order to use this wax as a base of medicine or cosmetics, the purification and refinement of the wax and its safety were investigated.

    Escolar's muscle contained about 20% lipid and 88.8% consisted of wax. The wax was composed of C32, C34, C36 and C38 and the main component was C34H66O2. The components of alcohols, as unsaponifiable substances of escolar wax, were mainly C16:0 and C18:1, as well as those of sperm whale (Physeter catodon) wax. The components of fatty acids, as saponifiable substances of the wax, were mainly C18:1 and those of highly unsaturated fatty acids a little. Escolar wax was refined by deacidification, decolorization with activated white soil, hydrogenation with Cu-Cr catalyst and molecular distillation. The refined wax was semisolid at room temperature and smelled faintly like margarine. Its safety was assayed by acute toxicity test, skin irritation test, eye's mucous membrane irritation test and contact sensitization test. The results showed that the refined wax was highly safe, indicating the usefulness for a base of medicine of cosmetics.

    Keywords - wax; escolar (Lepidocybium flavobrunneum); alcohol; fatty acid; hydrogenation; molecular distillation; medicine base; cosmetics base

  10. Selected Outbreaks:

    CDC/MMWR: Gempylotoxin
    Provides a list of Morbidity and Mortality Weekly Reports at CDC relating to this organism or toxin. The date shown is the date the item was posted on the Web, not the date of the MMWR. The summary statement shown are the initial words of the overall document. The specific article of interest may be just one article or item within the overall report.
    NIH/PubMed: Gempylotoxin
    Provides a list of research abstracts contained in the National Library of Medicine's MEDLINE database for this organism or toxin.
    Agricola: Gempylotoxin
    Provides a list of research abstracts contained in the National Agricultural Library database for this organism or toxin.

    For more information on recent outbreaks see the Morbidity and Mortality Weekly Reports from CDC.

  11. Education and Background Resources: 

  12. Molecular Structural Data: 

    Wax composed of C32, C34, C36 and C38 fatty acid esters; the main component was C34H66O2 (Ukishima, et al.)

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