Mention Blinky the three-eyed fish to any fan of “The Simpsons” and you’ll get a chuckle, but recent news about deformed fish in the real world isn’t a laughing matter.
University of Colorado researchers have found that wastewater discharged from sewage-treatment plants in Denver and Boulder is affecting the sexual characteristics of fish living downstream.
Some sucker fish studied by the team had both male and female organs, and others had sexual deformities.
The cause? It appears the chemical stew we send down our drains and toilets – cleaning products, cosmetics, medicine and hormone-laced human waste – is to blame and that the chemicals are disrupting the endocrine systems of the fish.
An endocrine disrupter, as defined by the Environmental Protection Agency, is “an external agent that interferes in some way with the role of natural hormones in the body.” Thousands of compounds, both natural and manufactured, are disrupters. Some scientists think the hormone estrogen, and compounds that mimic it, could be to blame.
The problem isn’t just a local one. Signs of such pollution were found in Kansas City in the mid-1970s. European, British and Canadian researchers have found drug leftovers in waterways. In 1999 and 2000, federal researchers recorded such contamination at numerous sites around the U.S. And a new study has discovered male bass with female reproductive organs in two rivers west of Washington, D.C.
The human effects of such pollution aren’t known. Contaminants generally have been found in very small concentrations, leading some experts to think there’s no immediate cause for worry.
But, CU biologist David Norris notes, “The problem is, is not the only source of this type of chemical. It’s in our food, it’s in our plastics. It’s in pesticides. We’re being bombarded all the time.”
And there haven’t been studies of how such compounds in water might affect humans, and treatment plants generally don’t filter them out. (There is technology available to filter the compounds.)
In the last 30 years, the U.S. has done a good job of keeping industrial pollutants and pathogens out of its water.
Researchers and water managers need to keep that record intact by digging deeper into chemical and drug pollution and by taking early steps to improve water treatment.
