1.1 This test method covers a long-term study to determine the oncogenicity potential of a substance in mammalian species such as the rat and mouse. the objective is to observe the test animals for a major portion of their life span for neoplastic lesions during exposure to various doses of a test substance by oral administration. 1.2 This test may also provide some information on long-term general toxicity. 1.3 This test method assumes that the user is knowledgeable in mamm