Hormonal chemicals may be imperiling fish

As they swim deep beneath Seattle's Elliott Bay, male English sole carry something in their bodies that's not supposed to be there: a protein usually found only in female fish with developing eggs.

These so-called "feminized" fish, first found in the late 1990s, are thought to be victims of human hormones and hormone-mimicking chemicals — flushed into the water from sewage-treatment plants, factories, storm-water drains and runoff from roads — that had made their reproductive systems go haywire.

Now a King County study has found that those chemicals, which come from sources as varied as birth-control pills and plastic bottles, detergent and makeup, are more widespread in the region's water than previously known.

The chemicals were found at very low levels, but some scientists worry that even in tiny amounts, they could mess with the sensitive reproductive systems of animals that already have plenty of challenges.

"We don't know very much about what these low-level exposures might do to the fish," said Lyndal Johnson, a biologist for the federal Northwest Fisheries Science Center in Seattle.

In many waters

The chemical lineup


Endocrine-disrupting chemicals, substances that act like human hormones, have been found in King County waters, and their fingerprints have been detected in English sole in Elliott Bay.

Here are some of the chemicals found in local waterways:

Bis (2-ethylhexyl) adipate: an ingredient in plastics, hydraulic fluid, bath oils, eye shadow and nail polish

Bisphenol A: used in some plastic food containers, as a liner in metal food containers, and in some dental sealants

Estradiol: an estrogen compound produced by women's ovaries

Ethynylestradiol, or EE2: synthetic estrogen used in birth-control pills and hormone-replacement therapy

4-nonylphenol: part of a class of chemicals used in detergents, pesticides and plastics

Sources: King County Department of Natural Resources and Parks; U.S. Environmental Protection Agency

Scientists for King County's Department of Natural Resources and Parks, which conducted the recent survey, said that a synthetic female hormone used in birth-control pills and hormone-replacement therapy has been found in streams and lakes, upstream from any sewage-treatment plants. That suggests that the prescription drugs are getting into the water from septic tanks or leaking sewer pipes.

The hormone, called ethynylestradiol or EE2, is one of many chemicals that can disrupt the endocrine system, which regulates animals' growth and development. The county scientists found EE2 in 22 percent of lake samples and 26 percent of stream samples. It was also found in every sample of storm water that flows into the Sammamish River in Redmond.

The county scientists also found endocrine-disrupting chemicals in storm water from Redmond and in runoff from the Evergreen Point Floating Bridge across Lake Washington.

"The things we detected were real low levels," said King County ecotoxicologist Deb Lester. "We did detect things, but they're ubiquitous compounds. It wasn't a surprise to detect them."

Happening elsewhere

The Seattle area isn't alone. In the Potomac River, male bass and sunfish have turned up with immature eggs in their testes. Scientists there have wondered whether similar chemicals also played a role in a string of fish kills.

In Nevada's Lake Mead, male carp that live near a pipe that spills treated Las Vegas wastewater had depressed levels of male sex hormone and smaller-than-normal testes. In California, "feminized" male fish have turned up in the Pacific Ocean off Los Angeles and Orange counties, with either the female protein or, in some cases, ovary tissue in their testes.

In Western Washington, there's concern the chemicals could hurt the reproductive success of fish, including salmon, which are already threatened by pollution, habitat loss and historic overfishing.

In Elliott Bay, the male sole that had the female protein were mostly concentrated in areas that get a lot of sewage outflow: offshore of Myrtle Edwards Park, off central downtown Seattle, and around the Duwamish River and Harbor Island.

Elevated levels have also turned up in Tacoma's Commencement Bay and in Puget Sound near Bremerton. Young chinook salmon in the Columbia River near Portland have been found with the same female enzyme as in the male English sole. That chemical usually appears only in mature female salmon getting ready to spawn.

The highest levels of the female protein in male sole were found at Harbor Island, near the mouth of the Duwamish River, and along Seattle's waterfront.

It's not just the males showing signs of sexual changes. Females in the most industrialized areas of Elliott Bay and the Duwamish tend to have eggs several months after their usual spawning seasons. And they tend to reach sexual maturity at a younger age, according to researchers at the Northwest Fisheries Science Center. Those changes are consistent with exposure to sex-related hormones.

While it's unknown whether the changes have hurt the fish in the wild, scientists are worried.

In one experiment in a lab on the Olympic Peninsula, rainbow trout exposed for two months to very low levels of EE2 had eggs with half the survival rate of their counterparts in hormone-free water.

"I think it just raises questions" about whether fish in the wild are being affected, said Irv Schultz, a scientist at the Battelle Marine Sciences Laboratory who conducted the experiment.

Human danger?

The levels found in lakes and streams are too low to pose a health risk to swimmers, said Paul Foster, a deputy director of the Center for Evaluation of Risks to Human Reproduction, part of the National Institute of Environmental Health Sciences.

But there is concern that endocrine disruptors in the environment could affect humans, especially developing fetuses that are undergoing critical changes choreographed by natural sex hormones, Foster said.

So the chemicals, which are often present at levels that couldn't be detected before recently developed lab techniques, have become the subject of intense research.

King County looked for endocrine-disrupting chemicals at more than 90 "sites of opportunity" stretching from Auburn to Bothell, where water has been tested regularly for other pollutants for years, said marine scientist Betsy Cooper.

The chemicals pose a particular challenge for sewage-treatment plants. Many of the plants aren't designed to remove them.

Scientists are testing whether the sewage-treatment technology that will be used at the Brightwater plant under construction in Snohomish County north of Woodinville can screen out endocrine disruptors, pharmaceuticals and other pollutants.

King County plans to sell treated water from Brightwater to a golf course and for irrigation in the Sammamish Valley. It won't be completely free of those chemicals.

Still, Lester, the county ecotoxicologist, said hormones aren't expected to pollute the groundwater or the Sammamish River because the recycled water's use will be limited. Also, some chemicals will break down into less-hazardous compounds. And others will bind with particles in the soil.

"It's highly unlikely that plants would be taking up Prozac," Lester said.

Warren Cornwall: 206-464-2311 or wcornwall@seattletimes.com

Keith Ervin: 206-464-2105 or kervin@seattletimes.com