Effect of Molecular Configuration on Relative Toxicity to House Flies as Demonstrated with the Four cis Isomers of Allethrin1

Abstract

l -Allethrolone d-cis-chrysanthemumic acid ester, the d-l ester, the d-d ester, and the I-I ester were, respectively, 0.33, 0.14, 1.8, and 0.056 as toxic to house flies (Musca domestica L.) as allethrin in space sprays applied by the Campbell turntable method. With the acid component of the molecule of the l form, the change from the l to the d form of the allethrolone component increased the toxicity of the ester by a factor of 2.4. With the allethrolone component of the l form, the change from the l to the d form of the acid component increased the toxicity of the ester by a factor of 5.8. With the common component of the d form, a similar change in the other component increased toxicity by factors 2.2 the two above. The effect of a change in each component simultaneously from the l to the d form was equal to the product of the separate effects. All the stereoisomers caused complete or nearly complete knockdown of flies at the concentrations used.