Inhibition and Induction of Aromatase (CYP19) Activity by Brominated Flame Retardants in H295R Human Adrenocortical Carcinoma Cells

Brominated flame retardants (BFRs) are persistent and ubiqui-tous chemicals in the environment, and they are found at incre-asing levels in tissues of wildlife and humans. Previous in vitro studies with the BFR class of polybrominated diphenyl ethers (BDEs) have shown endocrine-disrupting properties. Our study assessed the potential effects of nineteen BDEs, five hydroxyl-ated BDEs (OH-BDEs), one methoxylated BDE (CH3O-BDE), tetrabromobisphenol-A (TBBPA), its dibromopropane ether de-rivative (TBBPA-DBPE), and the brominated phenols/anisols 2,4,6-tribromophenol (TBP), 4-bromophenol (4BP) and 2,4,6-tribromoanisole (TBA) on the catalytic activity of the steroidogenic enzyme aromatase (CYP19) in H295R human adrenocortical carcinoma cells. Effects were studied in the concentration range from 0.5 to 7.5mM; exposures were for 24 h. Both 6-OH-BDE47 and 6-OH-BDE99 showed an inhibitory effect on aromatase activit