ABSTRACT
In the past 25 years, a number of very potent carcinogens of natural origin have been found, and the possibility that some of them may be involved in human cancer, particularly liver cancer, has led to extensive studies. This group of natural carcinogens included aflatoxin, which has been recognized as one of the most potent hepatocarcinogens in a wide variety of laboratory and farm animals such as ducks,1 rainbow trout,2rats,3 guppies,4 rhesus monkeys,5 and tree shrews.6
