Hepatocarcinogenic effects, aflatoxins

The rainbow trout is known to be one of the most sensitive animals to the toxic effects of dietary aflatoxin, especially the hepatocarcinogenic effects. The LD5Q of pure aflatoxin in trout is 0.5 mg/kg for a single dose, and 0.3 mg/kg for a dose given over a 5-day period. Trout fed levels as low as 0.4 yg/kg in the diet showed a significant incidence of hepatoma after 12 months exposure. In the latter case, the total intake of aflatoxin Bi over the one-year period would be 0.1-0.2 yg. In trout fed aflatoxin at 20 yg/kg for 20 days, incidence of hepatoma was 40% after 12 months. Recently, it was reported that when embryo-nated trout eggs were placed in an aqueous solution of aflatoxin Bl (0.5 yg/ml) for only 1 hour, the incidence of hepatoma was 40% after 10 months (20). Table II shows that the Fischer strain of rat is also very susceptible to the hepatocarcinogenic effects of aflatoxin B (18). 

Since the discovery of the Turkey X disease in 1960, aflatoxins have been established as mutagenic, teratogenic and hepatocarcinogenic in experimental animals. AFB] is the most toxic of this group of toxins and the order of toxicity is Bi>Gi>B2>G2. Aflatoxin M] is 10-fold less toxic than Bj, but its presence in milk is of concern in human health [66-68]. AFBj is also one of the most carcinogenic natural compounds known therefore, extensive research has been done on its synthesis, toxicity and biological effects [53, 69-72]. 

Soni, K.B., M. Lahiri, P. Chackradeo, S.V. Bhide, and R. Kuttan. 1997. Protective effect of food additives on aflatoxin-induced mutagenicity and hepatocarcinogenicity. Cancer Lett. 115(2) 129-133. 

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