The Relation between Exposure Time, Concentration and Toxicity in Experiments on Insecticides

Many toxicological experiments with insects involve at least three factors: the concentration of poison, the length of exposure and the percentage effect. The percentage effect may be related to either of the first two variables by the dosagemortality curve, using methods of computation which have been described elsewhere. Equations have also been reported which relate concentration and time at a constant mortality. The restriction of an investigation to any two of these three factors, however, is an unnecessary limitation even though at times it may be an experimental convenience. The combination of the three variables presents a problem that is both interesting and practical.