A drug test of a toddler experiencing a medical emergency revealed meth in their system, allegedly left out by the baby's caretaker in their home.

A one-year-old baby ingested methamphetamine in a Southwest Berkeley home this week, and had to be hospitalizated.

A passerby flagged down a Berkeley police officer on Monday around 1:30 p.m. in the 2400 block of Fifth Street, reporting that a child was displaying signs of seizing, lethargy, and drifting in and out of consciousness, as Berkeleyside first reported.

Authorities reportedly transported the one-year-old to Children's Hospital in Oakland, where a toxicology exam revealed the presence of methamphetamine in the toddler's urine, raising immediate alarm and prompting a police investigation.

The toddler is improving but still in the ICU, according to Berkeleyside, but police executed a search in the home of 35-year-old Mabel Miranda, the person responsible for the child. (KRON4 identifies her as the baby's mother.) Miranda reportedly admitted to bringing methamphetamine into the residence and leaving traces of the controlled substance on the floor, where the one-year-old had been crawling and had consumed some remnants.

Berkeley police also apparently discovered a loaded firearm, ammunition, and what is suspected to be heroin residue inside a container, prompting them to take Miranda was taken into custody on Monday evening. The Alameda County District Attorney's Office has subsequently charged her with one count of felony child endangerment, accompanied by two aggravating factors. She’s reportedly now in custody at the Santa Rita Jail in Dublin and is pleading not guilty.

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Image of Children's Hospital Oakland via Google Street View.