OECD Guidelines for the Testing of Chemicals, Section 4
- 2074-5788 (online)
The OECD Guidelines for the Testing of Chemicals is a collection of about 150 of the most relevant internationally agreed testing methods used by government, industry and independent laboratories to identify and characterise potential hazards of chemicals. They are a set of tools for professionals, used primarily in regulatory safety testing and subsequent chemical and chemical product notification, chemical registration and in chemical evaluation. They can also be used for the selection and ranking of candidate chemicals during the development of new chemicals and products and in toxicology research. This group of tests covers health effects.
Test No. 452: Chronic Toxicity Studies
- 08 Sep 2009
- 9789264071209 (PDF)
The objective of these chronic toxicity studies is to characterize the profile of a substance in a mammalian species (primarily rodents) following prolonged and repeated exposure.
The Test Guideline focuses on rodents and oral administration. Both sexes should be used. For rodents, at least 20 animals per sex per group should normally be used at each dose level, while for non-rodents a minimum of 4 per sex per group is recommended. At least three dose levels should be used in addition to the concurrent control group. Frequency of exposure normally is daily, but may vary according to the route chosen (oral, dermal or inhalation) and should be adjusted according to the toxicokinetic profile of the test substance. The duration of the exposure period should be 12 months. The study report should include: measurements (weighing) and regular detailed observations (haematological examination, urinalysis, clinical chemistry), as well as necropsy procedures and histopathology.