Induction of hepatic tumors in a teleost (Oryzias latipes) after treatment with methylazoxymethanol acetate: brief communication.

Liver neoplasms including trabecular hepatoma and cholangioma were induced in medakas (Oryzias latipes) by the addition of methylazoxymethanol acetate to their aquarium water at levels of 0.1-3 ppm for periods ranging from 1 to 120 days. More than 80% of the surviving fish developed tumors at 3 or 5 months after commencement of the treatment, irrespective of levels of the drug, when appropriate times of exposure were chosen.