Drugged Fish Hint at Danger in Water Supply
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, to be scooped up, their blood drawn and gonads removed.
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.
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.
There are problems with other wildlife as well: kidney failure in vultures, impaired reproduction in mussels, 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. "We find pretty much anywhere we look, these compounds are ubiquitous."
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.
More than 100 different pharmaceuticals have been detected in surface waters throughout the world.
"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."
While some researchers have captured wildlife and tested it for pharmaceuticals, many more have brought wildlife into their laboratories and exposed them to traces of human pharmaceuticals at levels similar to those found in water, aquatic plants and animals.
The results have been troubling.
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 separate lab study, the antidepressant also stunted reproduction in tiny fresh water mud snails.
When researchers slid hydras – a tiny polyp that under a microscope looks like a slender jellyfish – into water tainted with minute amounts of pharmaceuticals, their mouths, feet and tentacles stopped growing.
Tiny zooplankton, another sentinel species, died off in the lab when they were exposed to extremely small amounts of a common drug used to treat humans suffering from internal worms and other parasites.
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.
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.
"We’ll have to wait and see about this fellow," he said.
