Oncogenicity testing

Definitive carcinogenicity (oncogenicity) tests are often not required prior to the early studies in... 

EPA. 1985a. Memorandum. 6(a)(2) Data on chlordane. Chronic mouse and rat studies for oncogenicity testing. Acc. Nos. 252267, 254665, 251815, Review No. 004635. Office of Pesticides and Toxic Substances, Washington, DC. 

Exxon Biomedical Sciences (1986) Chronic toxicity/oncogenicity study in F-344 Rats. Test Material MRD-83-260. Project No 326075 performed at Exxon Biomedical Sciences, Inc., Unpublished Laboratory Report... 

EPA Toxic Substances Control Act Manufacturers and processors of the C, aromatic hydrocarbon fraction must test this fraction for the following neurotoxicity, mutagenicity, developmental toxicity, reproductive effects, and oncogenicity Yes EPA 1991a (40 CFR 799.2175) EPA 1987c... 

When testing compounds that are completely novel in a unique structural class and are in a therapeutic class that would not normally be tested in chronic rodent oncogenicity assays. 

In a carcinogenicity study, rats and mice were given the liquid orally at two different dose levels, 5 days a week for 78 weeks." Both female and male test animals exhibited early mortality compared with untreated controls, and a variety of neoplasms were found in both treated animals and controls. Although rats of both sexes demonstrated a positive dose-related trend, no relationship was established between the dosage groups and the species, sex, type of neoplasm, or sites of occurrence. The lARC concluded that an evaluation of the carcinogenicity of 1,1,1-trichloroethane could not be made. In a subsequent study, rats exposed at 15 00 ppm 6 hours/day, 5 days/week for 2 years showed no oncogenic effects. ... 

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