As Sergeant Dave Hoag arrests a man outside a general store in Preston, Wash., he uncovers a very small amount of methamphetamine.

"Are you just using meth or are you using heroin?" he asked the suspect as he put him in the back of his patrol car, where he questions him further. "Who's slinging most of the heroin up in the valley?"

Hoag offers to make the man's charges go away if he agrees to purchase heroin as an undercover informant. It is an offer the suspect is quick to accept, and an opportunity for Hoag to find dealers who are selling the deadly opioid to a growing number of young users in King County.

"If I can go after those people and I can use him to do that, in the interest of justice I think that's a fair trade," said Hoag, a 21-year veteran of the sheriff's office. "If I can get an informant to target a heroin dealer, than we're going to go after it."

Hoag believes that more teens and young adults are using heroin in King County than ever before, a trend that he is determined to put an end to. His observation, however, is a difficult one to prove.

Statistics would suggest that heroin hit its peak in King County in 1998. Data from the medical examiner indicates that fewer people are dying of heroin overdoses, just 50 in 2010 compared to 144 of 1998.

But, the man who compiles those figures is concerned that the numbers are masking a deadly phenomenon.

"It's disturbing and concerning and unfortunately not surprising," said Caleb Banta-Green, a research scientist at the University of Washington's Alcohol and Drug Abuse Institute. He has been examining drug trends in Washington State for a decade, and shares Sgt. Hoag's belief that heroin use is on the rise among youth in King County, and points to a different set of data to prove it.

"We've seen a big increase in the number of young adults (18-29) coming into drug treatment for heroin over the last 10 years in King County, that number has about doubled," he said. "It's concerning because it's generally several years before a person enters drug treatment after they've begun using a drug. So, if we're looking at young adults, it means they're starting in adolescence."

Banta-Green believes the number of young adults entering drug treatment for heroin is a good indicator of increased use among youth. Furthermore, he finds that the decrease in heroin-related deaths can be misleading.

"In the late 1990's, the purity (of heroin) was much higher, it was closer to 15 to 20 percent," he said. "We're now probably more in the 2 to 4 percent range. With declining purity, there is a decline in the number of overdoses."

But with increased use, it's only a matter of time before heroin overdoses go back up. Banta-Green said an early look at data from the first part of 2011 has already indicated an uptick in heroin deaths.

From opiates to opioids

For many youth hooked on heroin, their addiction began with prescription pain pills like OxyContin.

In an annual survey of heroin users, Banta-Green said 40 percent admitted that that they were initially hooked on prescription pain type pills.

"There's a very clear connection," he said.

Sargent Hoag agrees.

"OxyContin is absolutely a gateway to heroin use. There's no doubt about that," Hoag said. "The younger age group felt that there wasn't a stigma attached to a pharmaceutical pill. It wasn't 'dirty' like meth or cocaine."

But teens quickly became addicted, and soon realized that is was a costly high they couldn't live without.

"You're smoking three, four, five $80 pills a day, you're going to run out of money," he said. "You start selling your possessions, stealing from your parents, writing bad checks, shoplifting things."

It wasn't long before heroin emerged as an inexpensive and acceptable alternative.

"Physically and biologically and from a chemical perspective, the drugs are essentially interchangeable [...] the effect is the same," said Banta-Green. "But heroin is far cheaper."

And whether it be a star athlete or a star student, Sgt. Hoag has seen all types of teens become hooked on heroin.

"It could be somebody who comes from a broken home. It could be somebody who comes from a really good solid home," he said. "There is no one little niche that a heroin addict absolutely has to fit in."

Most of the young heroin users he has come in contact with, however, have one thing in common: they never expected their OxyContin experimentation would lead to full-blown heroin addiction, and neither did their parents.

"When I talk to parents, many of them are absolutely shocked when they find out that their child is addicted to heroin. It's just heartbreaking, absolutely heartbreaking."

Brandi Kruse, 97.3 KIRO FM