MURRIETA (CNS) – A Temecula couple who allegedly permitted their 10- month-old daughter to ingest fentanyl, nearly killing the baby, pleaded not guilty Tuesday to child cruelty.

David Matthew Carmona, 33, and Alicia Leann Rubio, 30, were arrested in March following a Riverside County Sheriff’s Department investigation.

Along with two counts of child cruelty, both are charged with a sentence-enhancing great bodily injury allegation.

They were jointly arraigned before Superior Court Judge Elaine Kiefer, who scheduled a felony settlement conference for July 19 at the Southwest Justice Center in Murrieta.

Each defendant is free on a $75,000 bond.

According to sheriff’s Sgt. Sean Liebrand, on the afternoon of last Oct. 11, patrol deputies were sent to a trauma center in the Murrieta area to investigate reports of an infant in medical distress due to exposure to unknown substances.

Liebrand said doctors administered Narcan on the belief the 10-month- old girl, identified in court documents only as “K.C.,” had ingested the synthetic opioid fentanyl. Narcan acts to halt the effects of an overdose.

According to Liebrand, the opioid antagonist was successful, and K.C. was stabilized.

The sheriff’s spokesman said detectives initiated an investigation and waited for results of the tot’s urine analysis, which allegedly confirmed the presence of opiates.

Over the ensuing five months, detectives continued to gather information and uncovered that “the juvenile’s parents … were fentanyl users, and (K.C.) had ingested a portion of their fentanyl,” the sergeant said.

Search warrants were obtained, and he alleged that when investigators scoured the couple’s apartment on Samantha Lane, they seized “10 fentanyl- laced M-30 pills and paraphernalia.”

“Toxicology results confirmed that Rubio, Carmona and the victim’s blood tested positive for fentanyl,” Liebrand said.

In addition to K.C., her sister, identified in documents only as “A.R.,” was determined to be at risk of exposure to the deadly drug, court papers alleged, resulting in the additional child cruelty count.

Neither defendant has documented prior felony convictions in Riverside County.

The current custody status of the children couldn’t be confirmed.

Fentanyl is manufactured in overseas labs, principally in China, according to the U.S. Drug Enforcement Administration. The agency says the substances are smuggled across the U.S.-Mexico border by cartels. It’s 80-100 times more potent than morphine and can be mixed into any number of street narcotics and prescription drugs, without a user knowing what he or she is consuming. Ingestion of only two milligrams can be fatal.

Officials say fentanyl is now the leading cause of death for Americans between the ages of 18 and 45 years old.

Couple Whose Tot Suffered Near-Fatal Fentanyl Exposure Arraigned