The effectiveness of 10 insect growth regulators (IGR) on small populations of Blattella germanica (L.) was assayed by treating the bedding material with an IGR-corn-starch mixture. Ethyl-3,7,11-trimethyl-2,4-dodecadienoate (ZR-512) was the most effective, with 5 ppm preventing normal metamorphosis in 97% of the population. But even with 100 ppm ZR-512, a mixed population of 100 adults and nymphs was not totally exterminated in 7 months, as some adultoids survived although no reproduction occurred. Besides interference with metamorphosis, these juvenile hormone mimics produced an increased melanization of both adultoids and supernumerary nymphs.
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Riddiford et al. (1975) studied this question.