With funding scant, intersex fish in Potomac remains mystery

By David A. Fahrenthold
Washington Post Staff Writer
Tuesday, November 24, 2009

KEARNEYSVILLE, W.VA. -- What's the problem with the Potomac River -- and could whatever it is spell problems for those of us who drink its water?

In 2003, scientists discovered something startling in the Potomac, from which at least 3 million Washington area residents get their drinking water: Male fish were growing eggs. But six years later, a government-led research effort still hasn't answered those two questions. Scientists say they still aren't sure which pollutants are altering the fish, or whether the discovery poses any threat to people's health.

The job is not easy: Scientists are looking for wisps of hormone-mimicking pollutants in the Potomac's vast, moving soup.

But the effort has also been held back, according to environmentalists and a federal researcher, by sparse funding and a lack of government focus.

The most tangible sign of the slow progress might be a frost-lined freezer at a government lab here in West Virginia. Inside are hundreds of samples of fish tissue collected from the Potomac in recent years, potential evidence that a federal scientist says she hasn't yet found the money to test.

"We'd be a couple years ahead" if the tissue had been tested, said Vicki S. Blazer, a biologist with the U.S. Geological Survey, who helped discover the Potomac's intersex fish.

There is still no evidence that whatever's affecting the Potomac's fish is a threat to humans who drink the river's tap water, which drinking-water authorities in the area say is filtered and safe.

Environmental activists have said they're surprised that such an attention-grabbing mystery -- gender-bending fish in the capital's water supply -- has languished so long without answers. On Wednesday, the nonprofit Potomac Conservancy spotlighted concerns about the fish in its annual "State of the Nation's River" report, saying the river held a "toxic stew" of chemicals that could mimic natural hormones.

"There's been some work done, but the pace of the research has been too slow," said Hedrick Belin, the group's president. "This canary in the coal mine, meaning the intersex fish, tells us that something isn't right with the water."

Which is exactly the kind of thing activists said after the first abnormal smallmouth bass were discovered in a West Virginia tributary in 2003. These fish don't look different on the outside, so the first ones were found by accident, as researchers investigated massive fish kills.

Under a microscope, they found that some male fish had nonfertile eggs inside their testes.

Since then, similar fish have been found all around the Potomac watershed. They have also been found across the United States. In a survey of nine other rivers this year, an average of 33 percent of male smallmouths were abnormal.

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