Police tape can be seen in front of an apartment building at 14480 East 104th Avenue where five people were found dead Sunday night, as seen on Monday, Feb. 21, 2022, in Commerce City, Colo. (Timothy Hurst/The Denver Gazette)

The Adams County coroner's office on Tuesday identified the five people who died Sunday in a Commerce City apartment of suspected fentanyl overdoses. 

The victims are:

  • Sabas Daniel Marquez, 24
  • Humberto Arroyo-Ledezma, 32
  • Karina Joy Rodriguez, 28
  • Stephine Sonya Monroe, 29
  • Jennifer Danielle Cunningham, 32

The causes of death are yet to be confirmed pending toxicology results, according to an email from the coroner's office. But 17th Judicial District Attorney Brian Mason previously said evidence suggests the people who died thought they took cocaine, but it was actually fentanyl. 

Mason said the scene looked like a "mass homicide."

"This is the nightmare scenario. This is five people dying without realizing the drug they're putting into their bodies," he said previously.

The Commerce City Police Department confirmed narcotics recovered in the apartment where the people died had a "presumptive" positive test result for fentanyl, a powerful, synthetic opioid. Investigators are trying to understand the quantity of fentanyl in a powdery substance found at the scene to determine if it was higher than expected for fentanyl-laced substances. 

David Olesky, acting special agent in charge of the Drug Enforcement Administration in Denver, said Tuesday that the substance found in the apartment tested for fentanyl but not cocaine. That doesn't mean cocaine wasn't present, he said, and further analysis in a laboratory setting will determine the makeup of the substance.

Olesky said the substance in the apartment was either entirely fentanyl or cocaine laced with fentanyl. According to the DEA, 2 milligrams of fentanyl is generally considered a lethal dose for most people. Olesky said the drug's presence in other substances — like cocaine, methamphetamine or heroin — is a persistent problem, fueled by its potency and cheap availability.

"The nature of how cheap it is," he said, "and there is no care for human life by the traffickers when they are deciding what to put inside their package, their concoction, so to speak. They're not concerned about the end user and their wellbeing." 

Fentanyl is a synthetic opioid that's far more powerful — and lethal — than morphine or heroin. Though it has legitimate medical use as an anesthetic, fentanyl has become increasingly prominent in the illicit drug market, thanks to shifts in the trade, its potency, and its low cost of production and transportation.

Olesky said the deaths in Commerce City highlight a problem officials have seen in Colorado and elsewhere nationwide: fentanyl's ubiquitous presence across other illicit drugs. It's now often mixed with other narcotics including cocaine, heroin, meth and OxyContin. Olesky said 40% of counterfeit pills seized by the DEA last year had a lethal dose of fentanyl. 

That mixing is helping to drive a spiraling overdose crisis, both in Colorado and nationwide. Data provided by the state Department of Public Health and Environment indicates at least 1,659 Coloradans fatally overdosed in 2021, though those numbers are still provisional. Of those deaths, fentanyl was involved in 803. 

Even provisional, 1,659 overdose deaths is the most in Colorado's history, and it shatters the previous record: In 2020, 1,477 residents fatally overdosed here, with fentanyl playing a role in 540 of those deaths.

Fentanyl's increasing presence in the drug market — and in other substances — means fatal overdoses will continue to rise in the coming years, Rob Valuck, who heads a statewide prescription drug abuse prevention group, said earlier this month. 

"The intensity and the stakes are much higher," said Valuck, who leads the Colorado Consortium for Prescription Drug Abuse Prevention. "It’s not Russian roulette with one bullet out of eight. Now, it’s three or four bullets out of eight. More people are dying, and there are fewer opportunities to intervene."

Many people taking other substances often don't know they're also ingesting fentanyl, health and law enforcement officials said. The synthetic, already more powerful than its sister substances, is even more potent in opiate-naïve users, whose bodies have no tolerance for that class of drug.

Its ubiquitous presence increases the need for broad availability of things like Narcan — which can be used to reverse opioid overdoses — and fentanyl test strips, which can be used to gauge fentanyl's presence in other substances. 

"People don't always know what they're getting," Adam Barkin, an ER physician at Sky Ridge Medical Center, said last week. "These illegal drug distributors, manufacturers — they are essentially mixing fentanyl in with meth, in with heroin, in with other drugs, sometimes formed as pills, sometimes not, and people are using them not even knowing that they're using fentanyl."

"Then taking into account (fentanyl's) potency," he continued, "they're overdosing on fentanyl when they didn't even know they were ingesting it or using it in any way. It's one of the true tragedies."

Denver Gazette reporter Lindsey Toomer contributed to this report.

Health reporter

Seth Klamann is the health reporter for the Gazette, focused on COVID-19, public health and substance use. He's a Kansas City native and a University of Missouri alum, with stops in Wyoming, Omaha and Milwaukee before moving to Denver.

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