Comments on the LD50 and acute eye and skin irritation tests: Prepared by the animals in research committee of the society of toxicology and approved by the SOT council

Abstract

Conduct of any form of testing of potentially hazardous materials in animals, including lethality or eye and skin irritation testing, should be undertaken only after careful consideration of the necessity for, the objectives behind, and the possible alternatives to, such testing. Acute toxicity testing to determine an approximate lethal dose provides a basis for a comparison of the relative toxicities of different materials. These data are used to classify materials for transportation and labeling, to provide information for treatment of acute intoxications, to aid in dose selection for subsequent toxicity studies, and to provide comparison data for evaluation and validation of alternative methods in toxicology. Although the classical LD50 test provides a general estimate of the quantity of chemical likely to cause death, much of the same information can be provided by other forms of testing in which significantly fewer number of animals are employed. Acute eye and skin irritation tests on chemical substances are conducted in order to characterize the hazards associated with ocular or dermal exposure. At present, tests in intact animals are the only means of assessing the potential hazard from such exposure other than direct testing in man. Although validated in vitro alternatives to eye and skin irritation tests in animals are not available currently, many tests under development show promise and may be useful as initial screening techniques. Complete validation of these alternate forms of testing for irritation may reduce the need to use whole animals. Until these procedures have been thoroughly tested and validated, the investigator will have to rely on conventional methods. In each case, however, attention should be given to the design and conduct of the study to reduce the number of animals and to minimize animal discomfort.