From Baltimore, at a meeting of the Society of Environmental Toxicology and Chemistry
Sediment-dwelling English sole living in and around Seattle's urban waterfront exhibit spawning anomalies that might compromise their reproductive success, a team of aquatic biologists finds. The changes indicate chronic exposure to environmental contaminants that mimic the animals' own estrogen, the primary female sex hormone.
When roughly half the male English sole at several collection sites near downtown Seattle were found to be making vitellogenin, an egg-yolk protein typical of females, toxicologist Lyndal L. Johnson of the National Marine Fisheries Service in Seattle and her coworkers decided to examine female soles. To their surprise, fish that should have spawned roughly a month earlier—as other sole in the Puget Sound region had—were still carrying their full loads of eggs.
To figure out why, the researchers began sampling female fish monthly, throu