Screening of Environmental Contaminants for Ecdysteroid Agonist and Antagonist Activity Using the Drosophila melanogaster B sub(II) Cell in Vitro Assay

The B sub(II) bioassay, which is based on an ecdysteroid-responsive cell line from Drosophila melanogaster, was used to screen a number of environmental contaminants for agonist and antagonist activity. The extensive number of compounds screened during the study are tabulated. None of the compounds possessed activity as ecdysteroid agonists, and only a few of the compounds antagonized the action of 20-hydroxyecdysone in the antagonist version of the bioassay. gamma -BHC, bisphenol A, and diethylphalate possessed greater antagonist activity, while androstenedione, DDT and its metabolites, diadzein, dieldrin, several dihydroxynaphthalenes, 17 alpha -ethynylestradiol, fluoranthene, 4-nonylphenol, nordihydroguaiaretic acid, zearalenone, and ZM189,154 possessed weak antagonistic activity at high concentrations.