State of knowledge on human exposures and biologic effects of economic poisons

Concern over the toxic potential of economic poisons developed around 1950 following widespread reports of ill‐effects from two main classes of these chemicals, the chlorinated hydrocarbons and organic phosphates. The large number of cases appears to have resulted from the increasing use of the pesticides in agriculture and by vector control personnel untrained in safety procedures. At the same time the development of resistance by many species of pests‐ has necessitated higher dosages and new compounds. Toxicity assessment, primary to measures for controlling use hazard, has been required under the Food and Drug act but largely in terms of life and death data from laboratory animals subjected to oral, parenteral, skin, and inhalation exposures. A new trend emphasizes the investigation of psychophysiologic factors, storage in body fat depots, tumorigenicity and carcinogenicity, effect on reproductivity and related genetic COnsiderations, potentiation by associated substances, antagonism, and therapeutics. The problem of impurities of high tOXicity in commercial products appeared early in production of aldrin and has been met with subsequently in connection with production of other materials. Vehicles and solvents have been found to play a role in tOXicity. Currently there is a difference between the evaluation basis commonly used in the U.S. and U.S.S.R. In the U.S.S.R. functional changes are frequently adopted as an index of toxicity. Cultural and climatic considerations play a significant role in determining the ultimate hazard.