Colorado’s Boulder Wastewater Treatment Plant recently received a multimillion-dollar upgrade, which was executed to address a number of problems — one of which was the high amount of chemicals seeping into the water table. After the upgrade, researchers found that the rate of feminization of male fish in Boulder Creek has decreased significantly. Feminization of fish and reptiles can result because of exposure to man-made chemicals that seep into the water table and act as endocrine disruptors. The chemicals can come from pesticides and fertilizers — as we’ve reported before — and from products people use every day, like soap, shampoo, cosmetics and pharmaceuticals.
A research team from the University of Colorado at Boulder looked into the issue in 2006 by studying the population of fish downstream from the wastewater treatment facility in Boulder Creek. Prior to the plant upgrade, the team led by Professor David Norris found that after just seven days of exposure to a mix of 50% clean water and 50% effluent water from the runnoff from the facility, male fish looked and acted like females. The researchers then went on to study fish samples from the University of Colorado at Boulder’s Museum of Natural History from 50 and 100 years ago and the samples showed no sign of feminization. The problem wreaks havoc on fish populations by causing the number of male fish to significantly decline.
“This is not the problem of water treatment plants, it’s our problem as human beings. We excrete natural and synthetic estrogens and use shampoos, detergents and cosmetics containing a variety of hormone disrupters that wind up in waterways. All of these different chemicals we are putting into the environment have the potential to alter the biology of animals and to affect ecosystems,” Professor Norris notes.
After the plant upgrade, Norris and his team studied the fish again, this time using pure 100% effluent water from the wastewater facility and found that male fish only started to develop female characteristics 28 days after they were exposed to the water. Not perfect by any means, but surely better than prior to the upgrade. After studying water samples, the group found traces of reproductive steroids naturally produced by people, BPA, phalates from plastic products, nonylphenols from detergents, pesticides and ethinylestradiol — a chemical common in contraceptives. Surely a chemical cocktail that could mess with anyone’s system.
Via Science Daily