Gender-Bending Fish Problem in Colorado Creek Mitigated by Treatment Plant Upgrade.

Byline: University of Colorado at Boulder

BOULDER, Colo., June 21 (AScribe Newswire) -- Male fish are taking longer to be "feminized" by chemical contaminants that act as hormone disrupters in Colorado's Boulder Creek following the upgrade of a wastewater treatment plant in Boulder in 2008, according to a new study led by the University of Colorado at Boulder.

But the problem of fish feminization -- which causes males to develop characteristics of females and to decline in numbers -- is a global one that is growing as a result of increasing chemicals like natural human reproductive steroids, pharmaceuticals, cosmetics, shampoos and soaps making their way into waterways, said CU-Boulder Professor David Norris, who led the study.

Norris, a professor of integrative physiology at CU-Boulder, said the multimillion-dollar general upgrade of the Boulder Wastewater Treatment plant northeast of Boulder, Colo., designed to solve …