FSC Provided Vital Link To Serial Killer

At the Forensic Science Center (FSC) at Lawrence Livermore National Laboratory (LLNL), most chemical analyses aim to inform national or even international security decisions. But the center also analyzes samples for investigations closer to home. One investigation FSC worked on was the case of Los Angeles-area serial killer Efren Saldivar, a respiratory therapist known as the "Angel of Death." Saldivar pleaded guilty in 2002 for administering lethal doses of the muscle relaxant pancuronium (Pavulon) to patients when he worked as a respiratory therapist at hospitals in Los Angeles.

The investigation of Saldivar began in 1998, when a suspicious coworker notified the police that an unusual number of deaths were occurring during Saldivar's shifts. Police collected much circumstantial evidence but were unable to make a direct link between drugs in Saldivar's possession and the dead patients. In May 1999, the Los Angeles County coroner exhumed bodies for autopsy. FSC then took up the task of trying to detect one of the drugs accessible to Saldivar, pancuronium, in samples of tissue, gravesite soil, and water from the caskets.

The samples came from patients who had died in 1996 and 1997. Several were extensively decomposed; some also contained embalming fluids, dyes, and formaldehyde. FSC chemist Armando Alcaraz, along with Brian D. Andresen and Patrick M. Grant at FSC, developed a method for extracting the drug from tissue by homogenizing samples with buffer, passing the buffer solution through a solid-phase extraction polymer, and finally eluting compounds from the polymer using various solvents (J. Forensic. Sci. 2005, 50, 196 and 215).

They spiked pancuronium into pig liver to use as control samples—using both fresh tissue and samples that were aged for several weeks in a fume hood. Between the exhumed samples and the pig livers, the lab wasn't exactly a pleasant place to be. "Even working in hoods the odor got into everything, even your clothes," Alcaraz recalls.

Using gas chromatography-mass spectrometry, as well as high-performance liquid chromatography coupled to a tandem, triple-quadrupole mass spectrometer with an electrospray ionization source, the team was able to identify pancuronium in six of the exhumed bodies. The results eventually led Saldivar to agree to a plea bargain in which he received six life sentences without the possibility of parole.