Studying chemicals in wash not cheap: $500,000

Friday, Jan. 15, 1999 | 11:44 a.m.

A spirited debate erupted at the Lake Mead Water Quality Forum between panel members and federal scientists who want to find out if chemicals in the lake are disrupting the breeding of sports fish.

The U.S. Geological Survey will spend $500,000 over a two-year period to study large-mouth bass and other sports fish to see if there is endocrine disruption. The goal is to find out how many chemicals are in Las Vegas Wash and Las Vegas Bay and to discover which compounds disrupt fish reproduction.

An earlier USGS study discovered high levels of female egg-yolk protein in bottom-feeding male carp, prompting further studies. Normal male carp have no female protein in their blood.

Treated sewage, valley surface runoff and contaminated ground water run into the wash, leading to Lake Mead, Southern Nevada's major source of drinking water. Any of these sources could contain endocrine disruptors.

Endocrine disruptors may be chemicals such as pesticides, prescribed drugs, estrogen-like compounds or treated sewage water that cause sexual changes in fish, wildlife and humans, said Steve Goodbred, USGS project leader at the Biological Resources Division in Sacramento.

"When we found female hormones in the Las Vegas Wash fish, it was the first time in North America," Goodbred said. The USGS needs to define what might cause such disruption, he said.

"Endocrine disruption occurs in wildlife as well as human beings," Goodbred said, adding that the answers won't come easy or cheap. But first, USGS wants to find out if there is endocrine disruption in the fish, since there is "strong evidence" of problems.

"At the end of two years, we are going to have a whole laundry list of potential compounds," Goodbred said.

Biologist Larry Paulson, a forum member, disagreed with the USGS approach. Why not study fish egg numbers and the size of the eggs first? he asked.

"This is a fishing expedition," Paulson said. "If you're going to do that, get a rod and reel."

UNLV biologist James Pollard, who has collected 243 sports fish this fall, offered to share his data with the USGS, including nodules discovered on some catfish collected from Lake Mead.

"For once I agree with Larry Paulson," Pollard said. "What is your scientific criteria for study?"

The Bureau of Reclamation, U.S. Fish and Wildlife Service, UNLV, the National Park Service and the University of Michigan will cooperate with the USGS on the study.