The mouse paw edema test and the tests for the determination of leukocytosis-stimulating and histamine-sensitizing activity are reproducible if standard samples are used and the properties under test are evaluated with reference to the characteristics of standard samples. The standard character of the weight gain test on mice is also enhanced if all conditions of the test are standardized. The most accurate information on the toxicity of the pertussis component of adsorbed DPT vaccine can be obtained if a single human dose (0.5 ml) is injected to mice and the toxicity of the vaccine is estimated from the weight gain registered in the test mice and the control animals. The use of standard samples in each test makes it possible to observe the conditions for controlling the toxicity of the tested preparations.