OECD 453/OCSPP 870.4300: Combined chronic toxicity/carcinogenicity studies

OECD 453/OCSPP 870.4300: Combined Chronic Toxicity/Carcinogenicity studies provide guidance to establish neoplastic effects, carcinogenic potential and general toxicity of the test substance. The mammalian species tested should be susceptible to the toxic/carcinogenic effects of the class of substances being tested – usually rat for oral or inhalation routes and mouse for the dermal route – with at least 100 rodents used at each of the three dose levels plus the control group (depending on the limit test result). 

Tests are conducted over 18-24 months. Administration route (oral, dermal or inhalation) depends on the toxicokinetic profile/physical characteristics of the test substance. Daily or weekly (more thorough) observation reports include animal weight, skin/fur evaluation and changes in gait. Blood counts, urinalysis, ophthalmological examinations, gross necropsy and histopathology are also performed.