Bookmark and Share

More press releases

For Immediate Release, November 16, 2009

Contact: Rob Mrowka, (702) 249-5821 or

Endocrine-disrupting Chemicals, Risk to Human Health and Wildlife Survival, Are Polluting Lake Mead

LAS VEGAS— The Center for Biological Diversity submitted condemning evidence to the Nevada Division of Environmental Protection today demonstrating that Lake Mead, Las Vegas Bay, and Las Vegas Wash are being polluted by unregulated endocrine-disrupting chemicals. The Center is requesting that the state include these waterbodies on Nevada’s list of impaired waters pursuant to section 303(d) of the Clean Water Act and establish and enforce limitations.

Endocrine disruptors are chemicals that alter the structure or function of the endocrine system, which uses hormones to regulate growth, metabolism, and tissue function. They have been shown to damage reproductive functions and offspring in animals such as birds and alligators, as well as in humans and their babies. Endocrine disruptors are entering Lake Mead’s water at costly concentrations via wastewater effluent and urban and agricultural runoff.

Lake Mead is the largest reservoir in the United States, part of a beloved national recreation area, and the sole source of Las Vegas’ drinking water. It is also federally designated critical habitat for the razorback sucker and home to many other rare species. Unfortunately those vital waters are now being poisoned by endocrine disruptors.

“Water is the most precious commodity a desert community can possess, and it is well past time that the Las Vegas Valley stopped fouling its source of drinking water,” said Rob Mrowka, the Center’s conservation advocate in Nevada. “The toxic soup flowing into Lake Mead is growing particularly serious as the effects of climate change diminish the flow of water into the lake, lowering reservoir levels and concentrating the pollutants.”

The highest concentrations of endocrine disruptors are found in Las Vegas Wash and Las Vegas Bay. This area is known spawning habitat for the razorback sucker and is a scant six miles upstream from the uptake structures for Las Vegas’ drinking water. Monitoring of these waterbodies has detected a variety of endocrine-disrupting chemicals, including organochlorine compounds, dioxins, polycyclic aromatic hydrocarbons, and other endocrine disruptors born from pesticides, pharmaceuticals, and personal-care products.

The purpose of the Clean Water Act is to restore and maintain the chemical, physical, and biological integrity of our nation’s waters. The EPA has delegated authority to the state to carry out the Act’s regulatory implementation and enforcement. This means the Nevada Division of Environmental Protection must establish water-quality standards that take into account the beneficial uses of the waterbodies. Section 303(d) of the Act requires it to develop a list of waterbodies, commonly known as a 303(d) list, needing additional work beyond existing controls to achieve or maintain water-quality standards.

Numerous studies on Lake Mead water quality, sediment, and fish and wildlife indicate that the waterbodies are being impaired by endocrine disrupting pollution. With Lake Mead at a historic low, the state has a heightened duty to protect the water both for drinking and for the health of fish and wildlife.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 240,000 members and online activists dedicated to the protection of endangered species and wild places.

Go back