Seven years ago this month, Hennepin County blitzed the metro area with notices urging residents to drop off their old, unused medications at a parking lot in St. Louis Park rather than flush them down the toilet.

County authorities collected 676 pounds of meds during the one-time, four-hour collection and branded the drive a huge success.

“It was often a family member disposing of medications after another family member died,” recalled Carolyn Marinan, the county’s public relations officer. “Some were near tears. They were happy to be rid of a very sad last reminder of a loved one and knowing it was responsibly handled.”

Officials with the Sheriff’s Office, key to initiating the program, were happy that people were getting controlled substances out of their medicine cabinets. Pharmacists were thrilled to see the proper disposal of medications, and environmentalists heralded the choices made to keep dangerous chemicals out of Minnesota’s rivers and lakes.

“They said we need to figure out how to do this permanently,” said Angie Timmons, an educator at the county’s Environment and Energy Department.

What began as a one-time experiment has morphed into a year-round project with 11 collection sites, open during the workweek and, four times a year, around the clock for an entire week.

On Aug. 16, the county hit a milestone, crossing the 100,000-pound mark in medicine collections since 2010.

“We used to encourage the public to dispose of pharmaceuticals by flushing them down the toilet, which we said was the safe thing to do because we didn’t want them floating around and misused by people getting their hands on them,” said Mark Ferrey, an environmental scientist with the Minnesota Pollution Control Agency.

But Ferrey said treatment plants were never designed to remove the medications’ chemicals from the waste stream. The new approach, he said, is to bring them to disposal sites where they are collected and later incinerated.

One study at St. Cloud State University concluded that antidepressants in open water can cause changes in the reproductive behavior of fish and delay their response to predators, Ferrey said.

A Canadian study found that a synthetic birth control hormone collapsed the minnow and trout population in a test lake.

Throwing pills into the garbage is also discouraged.

“If your waste goes to a landfill, there is a chance the medications could leach over time,” said Jennifer Volkman, statewide household hazardous waste program coordinator.

Landfill operators often take the “leachate” — or as it is sometimes called, “garbage juice” — and funnel it into the sewage system, she says. Trash is properly destroyed at a garbage burner, but sometimes people don’t know whether their trash is headed there or to a landfill.

Someone also might steal medicine out of a garbage receptacle. Animals might knock over a garbage can and consume the drugs, Volkman says.

Law enforcement authorities, meanwhile, warn that old and unused medicines left around the house can have lethal consequences.

Children can get their hands on them, addicts can steal them, or a person may accidentally take one pharmaceutical when they thought they were taking something else.

The results can be deadly, Hennepin County Sheriff Rich Stanek said.

“We saw 153 people die last year from opioids in Hennepin County, versus about 60 homicides,” he said. “Every one of them is tragic, every one is preventable.”

Over the years, the occasional county collection events were superseded by permanent collection boxes in sheriffs’ and police department lobbies. Today the county has 11 disposal sites.

The Sheriff’s Office and some cities in the county also distribute drug disposal bags. Add a little water to the bag and it deactivates the opiates, and the bag can then be thrown in the trash, Stanek said.

The sheriff has been visiting city councils across the county to lobby officials to get disposal boxes and distribute disposal bags to residents.

“We tell the residents of the county: It doesn’t matter whether it’s expired, unused or unwanted, it doesn’t matter if it is for human consumption or pet consumption, whether it is over-the-counter or controlled substances — they can take it to one of the drop-off boxes, and it’s good to go,” Stanek said. “They can leave them in the original pill bottle, they can put them in a plastic bag or a brown paper bag, it doesn’t matter to us.”

Sheriff’s deputies also have gone to businesses and assisted living facilities, asking people to bring in their unused medications for disposal.

“They love it,” Stanek said. “It’s community policing at its finest.”