Estrogen Has Adverse Effect on Trout’s Fertility

Trace residue from synthetic estrogen used in many oral contraceptives winds up in waterways and may hamper the ability of male rainbow trout to fertilize eggs, according to researchers at Pacific Northwest National Laboratory.

They reported in the June issue of Environmental Toxicology and Chemistry that, when exposed to levels of estrogen actually present in waterways, a mature male rainbow trout’s fertility levels decreased by as much as 50%.

Several scientific studies have previously shown the adverse effects of estrogen on juvenile fish, including instances of male fish developing female organs.