Extremely low concentrations of insect growth regulators (IGRʼs) have controlled mosquitoes, midges, flies, and biting lice in field tests. This effectiveness is undoubtedly related to the protected habitat of many of these pests of man and animals. Thus, species of Aedes have been controlled by applying as little as 0.14 kg IGR/hectare of water surface to the larval environment, but other species of mosquitoes such as Culex must be treated with much higher concentrations. All insects tested have shown marked susceptibility at a certain stage: 4th-instar Aedes larvae are controlled with 0.014 kg/hectare, but populations of mixed ages require 10 times that amount. Slow-release formulations of IGRʼs or those that protect the IGR from ultraviolet light are more effective. Otherwise, repeated applications are usually necessary to control a population containing all stages of a species. Development of new methods of application is being increasingly stressed, and feeding the IGR to cattle to control manure-breeding insects has been successful. Some IGRʼs have a rather broad-spectrum effect, particularly against manure-breeding flies; others are Selective, and a considerably greater quantity is needed for control of one species of fly than for control of another species.
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William F. Chamberlain (1975) studied this question.