Our drugs wind up in fish, too

Second of three parts.

LAKE MEAD, Nev. -- On this brisk, glittering morning, a flat-bottomed boat glides across the massive reservoir that provides Las Vegas its drinking water. An ominous rumble growls beneath the craft as its two long, electrified claws extend into the depths.

Moments later, dozens of stunned fish float to the surface.

Federal scientists scoop them up and transfer them into 50-quart ice chests for transport to a makeshift lab on the dusty lakeshore.

Within the hour, the researchers will club the seven-pound common carps to death, draw their blood, snip out their gonads and pack them in aluminum foil and dry ice.

More Coverage Stories Why water test results have been secret [03/11/08] Part I: Drugs on tap -- in our drinking water [03/10/08] Drugs in our drinking water [03/10/08] Video What are the consequences?

The specimens will be flown across the country to laboratories where aquatic toxicologists are studying what happens to fish that live in water contaminated with at least 13 different medications -- from over-the-counter pain killers to prescription antibiotics and mood stabilizers.

More often than not these days, the laboratory tests bring unwelcome results.

A five-month Associated Press investigation has determined that trace amounts of many of the pharmaceuticals we take to stay healthy are seeping into drinking water supplies, and a growing body of research indicates that this could harm humans.

But people aren't the only ones who consume that water. There is more and more evidence that some animals that live in or drink from streams and lakes are seriously affected.

Pharmaceuticals in the water are being blamed for severe reproductive problems in many types of fish: The endangered razorback sucker and male fathead minnow have been found with damaged sperm; some walleyes and male carp have become what are called feminized fish, producing egg yolk proteins typically made only by females.

Meanwhile, female fish have developed male genital organs.

There are problems with other wildlife as well: impaired reproduction in mussels and inhibited growth in algae.

"We have no reason to think that this is a unique situation," says Erik Orsak, an environmental contaminants specialist with the U.S. Fish and Wildlife Service, pulling off rubber gloves splattered with fish blood at Lake Mead.

For example:

bull; In a broad study still under way, fish collected in waterways near or in Chicago; West Chester, Pa.; Orlando; Dallas; and Phoenix have tested positive for an array of pharmaceuticals -- analgesics, antibiotics, antidepressants, antihistamines, anti-hypertension drugs and anti-seizure medications.

bull; In several recent studies of soil fertilized with livestock manure or with the sludge product from wastewater treatment plants, American scientists found earthworms had accumulated those same compounds, while vegetables -- including corn, lettuce and potatoes -- had absorbed antibiotics.

bull; Elsewhere in the world -- from the icy streams of England to the wild game reserves of South Africa -- snails, fish, even antelope are showing signs of possible pharmaceutical contamination.

"It's inescapable," said Sudeep Chandra, an assistant professor at University of Nevada, Reno who studies inland waters and aquatic life. "There's enough global information now to confirm these contaminants are affecting organisms and wildlife."

In one study, freshwater mussels exposed to tiny amounts of an antidepressant's active ingredient released premature larvae, giving the next generation lower odds of survival.

In a landmark, seven-year study published last year, researchers turned an entire pristine Canadian lake into their laboratory, deliberately dripping the active ingredient in birth control pills into the water in amounts similar to those found to have contaminated aquatic life, plants and water in nature.

After just seven weeks, male fathead minnows began producing yolk proteins, their gonads shrank, and their behavior was feminized -- they fought less, floating passively. They also stopped reproducing, resulting in "ultimately, a near extinction of this species from the lake," said the scientists.

While the Canadian study was prompted by human intervention, similar die-offs have occurred in the wild.

In November, at the annual Society of Environmental Toxicology and Chemistry meeting in Milwaukee, 30 new studies related to pharmaceuticals in the environment were presented -- hormones found in the Chicago River; abnormalities in Japanese zebra fish; ibuprofen, gemfibrozil, triclosan and naproxen in the lower Great Lakes.

Many of those studies refer to the heralded research at Lake Mead. There, on a recent morning, Steven Goodbred struggled to hold a large wriggling carp with both hands. On the outside, the carp looked fine, vibrant and strong, but the U.S. Geological Survey scientist assumed the worst.

"Typically we see low levels of sex steroids, limited testicular function, low sperm count, that kind of thing," he said slipping the fish into a holding tank and closing the lid. "We'll have to wait and see about this fellow."

These carp live, eat, reproduce and die at the mouth of what amounts to a 30-mile-long drainage system that starts within the toilets and sinks of the casinos, hotels and homes of Sin City.

Other communities in Nevada, as well as locales in California and Arizona, also draw on Lake Mead.

"Lake Mead is a fortuitous worst-case scenario" for study, said environmental toxicologist Greg Moller, holding a bottle of Lake Mead water he planned to take back to his lab at the University of Idaho. "You've got the wastewater, you've got the documented impact on wildlife, and you have drinking water uptake."

At the same time, scientists are looking for remedies. In Las Vegas, just off the Strip at the Desert Research Institute, microbial biologist Duane Moser optimistically held a tray of increasingly murky test tubes.

"We put a little bit of estrogen in here, and then we added a particular bacteria, and guess what? The bacteria are consuming the estrogen," he said. Someday, perhaps, scientists will be able to use these special bacteria to clean estrogen out of contaminated water.

"It's early, but it's promising," he said.