I myself prefer single authored books for basic understanding of a scientific field the second circumstance leading to the present volume was the avail ability of teaching notes from my course on the toxicology of insecticides. The toxicity of a pesticide is its capacity or ability to cause injury or illness the toxicity of a particular pesticide is determined by subjecting test animals to varying dosages of the active ingredient ai and each of its formulated products the active ingredient is the chemical component . Toxicology is one of the fastest moving scientific fields in the areas of insecticide toxicology many new advances have been made since this treatise first appeared therefore it would not be easy to write even a review paper that would not be outdated by the time it was published. General principles of insecticide toxicology classification of insecticides modes of action of insecticides metabolism of insecticides by animals and plants entry of insecticides into animal systems dynamics of insecticide movement in the animal body movement of insecticides in the environment environmental altertion of insecticides residues effects of pesticides on wildlife hazards . Reference 2 general principles of insecticide toxicology 21 evaluation of toxicity 22 analytical methods for insecticides 23 references 3 classification of insecticides 31 history and general groupings of insecticidal compounds 32