The youngest men booked into the Hennepin County jail so far this year are increasingly testing positive for prescription painkillers, while fewer were using cocaine and methamphetamine, according to a new federal study.

Just over 68 percent of all men booked into the jail had tested positive for illegal drugs, according to the study. Men 21 and younger showed the biggest shift, with 5.6 percent testing positive for oxycodone, a narcotic commonly found in prescription painkillers. In last year's study, none in the age group had used oxycodone.

Meanwhile, the same age group showed a drop in cocaine and methamphetamine use. None this year were found to have used either drug. Last year, 7 percent had used cocaine and 3.5 percent had used meth. Opiates such as heroin were found in 6 percent of the inmates. Twice as many young inmates also tested positive for multiple illegal drugs this year as last year.

Hennepin County Sheriff Rich Stanek said the numbers are a snapshot of the past six months, but hold true with the trends they've seen over the past six to seven years. "I'm optimistic because neighbors, parents and law enforcement are doing a pretty good job of educating young people about the dangers of cocaine and meth, and so you see that has curtailed," Stanek said. "But we haven't done a very good job in terms of prescription drugs. It's a ready supply, it's not closely monitored."

Stanek said the increase in oxycodone consumption was somewhat disconcerting, as was heroin consumption, which remained steady. The study was done by the Arrestee Drug Abuse Monitoring Program for the Office of National Drug Control Policy. The Hennepin County jail is one of 10 sites across the country where the program measures drug use among inmates within 48 hours of their arrest. People who have been arrested volunteered to be interviewed for the study, and their information was verified with drug testing.

Marijuana, which can stay in a person's system for up to 30 days, remains the most commonly detected drug at the time of arrest of all male inmates at 53.1 percent, followed by cocaine, opiates, methamphetamine and oxycodone, which remain in the body for three to four days. Among those arrested for a violent crime entering the jail, more than 62 percent had drugs in their system, according to the study.

Abby Simons • 612-673-4921