The Judicial Investigation Agency (OIJ) is probing whether carbon monoxide poisoning caused the death of 14-year-old Miller Gardner on March 21 in a hotel room at Arenas del Mar in Manuel Antonio, where he was staying with his family. Rándall Zúñiga, OIJ director, reported that tests conducted last Friday by a specialized Fire Department team and Forensic Engineering personnel detected dangerously high carbon monoxide levels—up to 600 parts per million (ppm)—in the room.
“Safe levels should be zero,” Zúñiga noted. “This points to a theory that this individual may have died from inhaling these toxic gases.” Carbon monoxide, an odorless and colorless gas, can cause symptoms like nausea and dizziness at lower levels, and unconsciousness or death above 400 ppm with prolonged exposure.
Investigators identified a mechanical room adjacent to Gardner’s room as the likely source of the contamination. The Fire Department and Ministry of Health have been alerted to address the hazard, though it’s unclear if the hotel has been closed or modified pending further action.
The investigation, supported by the FBI, continues as forensic toxicology results are awaited to confirm Gardner’s cause of death. Zúñiga said initial findings have been shared with U.S. authorities. The Gardner family had dined at a restaurant outside the hotel on Thursday, March 20. Upon returning, Miller reported feeling unwell and was seen by a doctor arranged by the hotel. The next morning, a relative found him unresponsive in his room. Authorities have not confirmed whether other family members exhibited symptoms.
The case is being handled by the OIJ’s Regional Subdelegation in Quepos and Parrita. Gardner’s body has been repatriated to the United States from the Judicial Morgue. Arenas del Mar management has not yet released a statement regarding the incident or the ongoing investigation.
