HENNEPIN COUNTY, Minn. (NBC) -- Sgt. Jennifer Johnson is in charge of the medicine disposal box at Minnesota's Hennepin County Sheriff's Water Patrol office, but it's more than a job, it's a personal mission.
"You never think that it affects your family," Johnson said. "But I have a 19-year-old nephew that he and his friends decided to take some prescription pills that didn't belong to them and they cut them into thirds and each one took a piece and they were drinking alcohol with it and unfortunately my nephew went to bed and didn't wake back up."
That nephew, Luke Murphy, a student at the University of Wisconsin-Milwaukee, had combined the drug Suboxone with alcohol.
Johnson said it was his first time.
"Their friend took those pills before and thought it would be fun for everybody. Unfortunately that wasn't the case," she said.
LeeAnn Mortensen of North Memorial Injury Prevention said one reason that prescription drug abuse is a growing problem is that they're easy to get.
"About 70 percent of kids actually get them from friends and relatives," she explained.
That's why many counties now provide prescription drug drop off sites.
Hennepin County alone has six sites, which often need to be emptied two times a week.
So why not flush the pills or dissolve them down the drain?
"In the end, they all end up in our groundwater and that's not where we want them," Mortensen said.
Trace levels of drug residue have been found in drinking water.
It is possible some also comes from prescription drugs passing through people's bodies.
The drugs left at the drop off sites are incinerated.
Johnson hopes to prevent someone else from losing their loved one by getting unused drugs out of people's homes.
"Take that stuff out of your closet, out of your medicine cabinet, you don't want your kids to get to it. I'm proof of that," she said.