Mixed Antiandrogenic Chemicals at Low Individual Doses Produce Reproductive Tract Malformations in the Male Rat

The study demonstrated that in utero exposure to a mixture of 18 "antiandrogenic" chemicals, even at low individual doses, resulted in permanent reproductive tract malformations in male rats. Pregnant dams were exposed to various dilutions of the chemical mixture, and male offspring exhibited neonatal, pubertal, and permanent adult effects across all dose levels. Notably, even the lowest dose, which was approximately 80 times below the lowest observed adverse effect level for each chemical, led to permanent reductions in reproductive tissue weights. At the highest dose, 100% of male offspring had severe genital malformations. This indicated that a combination of chemicals, despite acting through different mechanisms, could produce additive adverse effects.