Scientists Find Residue in Ore. Streams

Monday, May 07, 2007

ADVERTISEMENT

PORTLAND, Ore. —

Scientists testing the beds of streams around Portland found the residue of the region's medicine cabinets and coffee shops. The list of compounds includes many known by such names as Prozac, Tagamet, Benadryl, and Micatin, as well as the caffeine that makes the Northwest edgy.

The scientists were surprised, and troubled. They say they don't know how the chemicals might affect fish or other life.

Among other things, they worry that antibiotics and other substances could help bacteria and other organisms develop resistance to drugs and pesticides.

"The consequences may be major, but to some extent they may be subtle," Joseph Rinella of the U.S. Geological Survey in Portland, told The Oregonian.

Some of the compounds have been detected in local waters before, but the new research by Elena Nilsen of the survey's Portland office looked at sediments because they may collect much of what passes by in the water.

The study is part of a national effort to identify the main pollutants and their sources in major water systems marked for cleanup. The findings are to be presented this week at a conference on pollution and contaminants in the lower Columbia River.

Many of the compounds are thought to have an obvious source: human sewage that gets through treatment plants not designed to deal with them.

"People just assumed a lot of that stuff was removed," said Sheree Stewart, drinking water protection coordinator at the Oregon Department of Environmental Quality. "Actually a lot of what is in the raw water gets through."

The chemicals could include the contents of surplus pills flushed down toilets, a practice that's no longer recommended. Some local agencies are working on programs to collect surplus pills to keep them out of the water.

The river-bottom studies detected what are called endocrine-disrupting compounds found in drugs, as well as other chemical compounds.

Scientists working on related studies found signs that young salmon of both genders from the Willamette River around Portland held traces of an egg yolk protein usually found only in adult female fish beginning to develop eggs _ something that would happen if their bodies were tricked by artificial endocrine disrupters that interfere with the systems that manage hormones.

"So they're being exposed to something, we just don't know what it is," said Lyndal Johnson, head of reproductive toxicology at the federal Northwest Fisheries Science Center in Seattle.

"It's quite interesting, and a little disturbing," she said.

A notable finding is that concentrations of some drugs and other chemicals are higher in small, urban waterways such as Fanno Creek than in the much larger Columbia, Nilsen said. That may be at least in part because the volume of the Columbia dilutes the drugs.

___

Information from: The Oregonian, http://www.oregonlive.com