Naperville police have closed their investigation into the deaths earlier this summer of two 17-year-olds after toxicology tests showed they each died of different drug-related causes, officials said.
Police had previously characterized the deaths of Jonathan Betten and Ryan Warner as "suspicious" after the men each were found dead in Naperville less than a week apart in July.
This week, coroner's officials said toxicology screens determined both teens died of separate drug-related causes. As a result, police closed their investigation, said Naperville Sgt. Gregg Bell.
"There was no connection between the two," Bell said, adding police found no signs of foul play.
Betten, who was pronounced dead at a hospital after losing consciousness in a friend's basement the morning of July 1, died of combined drug intoxication involving alcohol and over-the-counter cold medicine, Will County Chief Deputy Coroner Bob Brenczewski said.
Warner, who was found unresponsive on his back porch July 6, died of heroin intoxication related to recreational drug use, according to the DuPage coroner's office.
Both deaths were ruled accidental.
Police previously said evidence of over-the-counter medication, prescription drugs and alcohol was located at the home on the 3500 block of Sweet Maggie Lane where Betten was found.
At Warner's home on the 3600 block of Schillinger Court, less than a mile from Betten's home on the 2400 block of Cloverdale Road, drug paraphernalia used to take heroin was found, according to police.
Beth Sack, manager of addiction services at Linden Oaks at Naperville's Edward Hospital, said that while tragic, the teens' deaths should draw needed attention the prevalence of drugs in the community, particularly heroin.
"I don't think I want to use the word epidemic, but it definitely is a problem," she said Thursday. "Awareness from the parental point of view is key right now. We all want to feel like it couldn't be our child, but we need to be aware this is happening. It really can happen to anybody."
Sack said it can be difficult to tell whether someone is using heroin, depending on the severity of the addiction. She said some users may feign sickness, while others are able to mask their use because they have high tolerances and don't show obvious changes in behavior.
Sack said some adolescents get high off forms of cold medication that can act as hallucinogens when taken in large doses. Mixing in alcohol and other substances, she said, can increase the chances of a fatal reaction.
"This can be the outcome when that happens," Sack said. "It's an unfortunate, traumatic event."
Betten was an incoming senior at Neuqua Valley High School and had participated in a number of service projects and mission trips as a member of St. Raphael Catholic Church in Naperville, according to an obituary. An avid rock climber and canoeist, he was remembered for his "sense of humor, his compassion for others and his enthusiasm," an online obituary says.
Authorities said Warner was a student at Indian Plains High School in Aurora; further information wasn't available.
Attempts to reach both families were unsuccessful.