Local agency may direct extensive water test

Tuesday, Dec. 14, 2004 | 11:06 a.m.

Researchers at the Southern Nevada Water Authority could take the lead in examining the impact of low levels of pesticides, industrial products and pharmaceuticals under a proposal to be considered by the authority board Thursday.

The $503,000 proposal would include 14 municipal water agencies, the University of Wisconsin and two subcontractors to review previously published research and conduct primary research that would expose cells to the substances, many of which have become prevalent throughout the environment and in drinking water sources -- including Lake Mead, the source of 90 percent of Las Vegas' drinking water.

The study would be conducted under the auspices of the American Water Works Association Research Foundation, a national nonprofit agency that conducts research into public water issues.

The Water Authority's contribution would be about $50,000, according to Ron Zegers, director of the Southern Nevada Water System, a unit of the Water Authority. The other players would contribute the bulk of the funding for the project.

Many of the targeted compounds are known to affect hormone levels in humans. However, there is considerable uncertainty over how much of the chemicals would be dangerous alone or mixed together.

Zegers said locally and nationally, people need to have more information on the effects of such materials.

Lead investigator for the research effort would be Shane Snyder, a scientist who has worked with the Water Authority for five years. Snyder has worked with the Environmental Protection Agency as the federal agency has struggled to come up with a health standard for perchlorate, a rocket-fuel chemical that has entered Lake Mead through industrial sites in Henderson.

Snyder said, however, that this study would not focus on perchlorate, which is also a disrupter of hormones, but on other suspected agents.

"We're really not looking at perchlorate," he said of the new study, while noting that the work on the rocket-fuel component continues. "We're more looking at pesticides, plastic by-products, trace organics. Is there an impact at low levels?"

He said the issue is extremely important to the Southwest, where water shortages are already occurring and more are expected. In that situation, more reuse of water is needed, meaning that more understanding is needed to show the potential impacts of the compounds that could enter or be concentrated by the reuse, he said.

"We can't afford to throw water away," said Snyder, who received his doctoral degree from Michigan State University in 1997. "We have to reuse."

The work is possible today where it would not be even a few years ago because of advances in technology. New technology allows scientists to find evidence of such chemical compounds in quantities as low as a few parts per trillion or quadrillion.

At those levels, the compounds can be found throughout the environment. Pesticides run down from lawns and farms into the Colorado River. Pharmaceuticals are passed from humans into the waste stream. The suspect chemicals from plastics are byproducts of an industrial society which uses the material for nearly every part of modern life.

"We're trying to find a reference dose," Snyder said. "We're trying to determine at what level you expect these compounds to be relevant to human health."

Snyder said people and other mammals are already exposed to many potential hormone disrupters in the natural world. Plants and plant products such as soybeans produce "estrogenic compounds" that can look a lot like man-made chemicals, he said.

Those plant products can and do cause significant hormone problems for some animals, he said. But it is not clear at what level the artificial compounds would have that effect.

While some research has occurred and continues to go forward, Snyder said there are gaps.

"The EPA has no program in place to look at the health effect of pharmaceuticals in the environment," he said.

The turnaround for the project could be relatively rapid. Snyder said he hopes to have a review of the existing research completed and submitted for publication to a leading scientific journal within a year. The study of the impact of the compounds on cellular growth could take another year in the project.

Zegers warned that the research project would not answer all the questions that people have about the potential health effects of such chemical compounds, but it would add to the information that is available.

"That's why we do research," he said. "It's a beginning. The science is in its infancy."