SEATTLE - Tens of thousands of prescriptions are filled each day at clinics and pharmacies across Washington State. Workers at the Group Health facility in Tukwila alone will fill between 10,000 and 12,000.

But the facility does something the others don't - it takes back the pills patients don't use.

"You know we started this program back in October of 2006 and since that time we've collected well over two tons of unwanted, expired, unused medications from consumers," said Shirley Reitz of Group Health Pharmacy Services.

They come in by the buckets from Group Health facilities across the state.

Patients are urged to take back their unused drugs to those facilities and drop them in specially designed, secure metal boxes.

It's all about security through the entire process, beginning with the deposit boxes. These things are like mailboxes, they're solid and bolted to the wall and floor. They're not going anywhere."

Then two employees at a time must empty the boxes, which are then sent to the Tukwila facility where they are sealed up and sent off for incineration.

"We're getting drugs out of the system and from homes where they can be abused, or misused or accidental poisoning could happen," said Reitz.

It used to be a good flush was the way to get rid of old drugs, but that was before scientists discovered traces of prescription drugs in streams, rivers and in creatures that live in them.

Officials with King County Hazardous Waste say much of the unwanted medicines thrown in toilets or thrown in the trash will end up in surface or ground waters, potentially impacting aquatic organisms. A study by the United States Geological Survey showed pharmaceutical compounds in 80 percent of the streams surveyed across the country.

"We are concerned if we're finding ibuprofen or valium or estro.gen or other kinds of chemicals in the waters," said Dave Galvin of King Co. Hazardous Waste

King County and Group Health officials will testify before the legislature this week about the need for a statewide medicine take back program. They say unused drugs are toxic waste and they're contaminating medicine cabinets in nearly every home in the state.

They expect opposition from drug makers, who would have to pay for the disposal.

Bartell Drugs will join Group Health Cooperative in providing drop boxes where consumers can dispose of old medications.

Group Health has medication disposal units in 24 pharmacies in King, Pierce, Snohomish, Kitsap, Thurston and Spokane counties.