By Pat Pheifer and Meghan Holden

Prescription drug drop-off sites in four metro counties collected 15 tons of medication last year, putting a big dent in the availability of secondhand painkillers for drug abusers.

Police, sheriffs and county officials in recent years have set up dozens of prescription drop boxes and ramped up a public education campaign warning of the dangers of keeping leftover drugs in medicine cabinets. That can be an attractive hazard to young people hoping for a quick high. Throwing the drugs in the trash isn’t a good idea, and flushing them down the toilet can contaminate groundwater.

Hennepin County, the metro area’s most populous, collected 7 tons of prescribed drugs last year. Dakota County collected 3 tons, Ramsey County 2.7 and Washington County 2.3. The collected drugs are incinerated.

Though the Mower County Law Enforcement Center’s drop box was inaccessible during 2013 construction, the county still collected more than 3,000 pounds of prescription drugs, according to Sheriff Terese Amazi.

Painkiller addiction can become even more dangerous because it’s increasingly a gateway to heroin use, authorities say.

“All along we’ve been trying to draw attention to the fact that when you look at the number of heroin deaths that are going on and you look at the track people got on getting to heroin, you find prescription drugs were somewhere in the formula,” said Dakota County Sheriff Dave Bellows.

If people experimenting with drugs have easy access to opiates like Percocet or OxyContin in their family home, when the prescription drugs run out, they buy them on the black market, Bellows said. But those types of drugs are expensive on the street, and a lower-cost alternative is heroin, he said.

Hennepin County Sheriff Rich Stanek agreed: “If they can’t get prescription drugs, then they turn to heroin,” especially young people.

And the heroin in today’s illegal marketplace is plentiful, powerful and pure. In 2010, there were eight heroin overdose deaths in Hennepin County. In 2013, there were 54.

“We’ve worked really hard … to get that message out,” Stanek said.

Dakota County started its program in 2011 with three drop-off sites. It now has 11. Hennepin County, whose program was started in 2012 with one box, added five more last year. Ramsey County started in 2011 and has two sites. Washington County has three.

The total collected in 2013 in those four counties is roughly the weight of a fully loaded 84-passenger bus or three full-grown African elephants.

Bellows said 15 to 20 percent of the drugs collected in the boxes are prescription painkillers.

A drop box for prescription medication is located in the lobby of the Mower County Law Enforcement Center.