A Stanford University graduate medical student faces charges of poisoning her fellow lab mates in a series of incidents that occurred in September 2014, according to court documents filed in Santa Clara County Superior Court.
The 26-year-old student was arrested on November 11, 2014, and is charged with four felonies after allegedly spiking her lab mates' water with paraformaldehyde in the Stanford School of Medicine lab.
The graduate student, who no longer attends Stanford, had been working in the lab for three years. She was a Singapore National Science Scholar at the Agency for Science, Technology and Research, according to online government reports.
But she appeared to be under duress while at Stanford and was unsure of herself, witnesses in the lab told police. Described as quiet, shy, meticulous and a good student, she once expressed that she was stressed out, according to a police report.
The incidents began in late August or early September. A lab colleague drinking from a water bottle she had left on her desk experienced immediate burning to her throat and mouth. She then noticed the water smelled like paraformaldehyde, which is readily available in the lab. She rinsed out her mouth and the bottle, according to the police report.
After that incident, the colleague began smelling her water bottle before drinking. The bottle smelled like paraformaldehyde about four times a week for the next two to three months, she told police. She did not suspect anyone was tampering with her water bottle, but she eventually threw it away, according to the police report.
After the additional incidents, which other colleagues in the lab confirmed smelled like paraformaldehyde, the first victim preserved a small amount of the water in a vial. The presence of 884 parts per million of paraformaldehyde in the preserved water was later confirmed by a laboratory's testing, according to police.
A second lab colleague also experienced multiple incidents during September or October, in which her water bottle appeared to have been tainted with paraformaldehyde, according to the police report. This second colleague felt a burning sensation in her throat after drinking from her water bottle. She began to salivate uncontrollably and felt her esophagus contracting, according to the report.
During a second incident on Nov. 6, she took a big swig from her water bottle and had the same reaction. The experience was 10 times worse than before, she said. She also discarded her water bottle, according to police.
Paraformaldehyde can cause a host of maladies. It causes stomach irritation and papillomas in rats and mice when ingested and it can cause skin irritation in humans, but it is not known to be carcinogenic in humans when ingested, according to the World Health Organization (WHO). It may cause nausea, vomiting and diarrhea. Prolonged ingestion may affect the kidneys and cause gene mutations.
The two victims had their blood drawn at a student clinic to test for abnormalities, police noted. The water bottle of a third colleague was later tested and found to contain paraformaldehyde, according to the report.
The student was also accused of sabotaging a fourth colleague's research. In mid-August, stem cells the colleague had successfully grown started to mysteriously die overnight.
The colleague moved her cell plates to another lab and another incubator where they successfully grew for a time but then also mysteriously died. At one point, she discovered the accused student standing in front of her incubator with the door open. The colleague also discovered an open bottle of Trypsin, an enzyme that causes cells to detach and float up, on the incubator hood where the suspected student was allegedly standing, she told police.
To determine if she was being deliberately targeted, the colleague mislabeled some of her cell plates in her incubator and left others with her name on them. All of the experiments with her name on them died while the others did not. The colleague then reported the incident to the head of the lab. Video footage later obtained also placed the accused student in the lab where she was doing no work, according to the police report.
Another colleague told police that a 100-milliliter bottle of paraformaldehyde on her desk should have had 90 milliliters remaining. But after the alleged tainting incident with the first victim, she noticed the bottle was nearly empty.
The student allegedly admitted to tainting the water bottles and to destroying her lab mate's stem cells. Prior to adding paraformaldehyde to the bottles, she had started putting dish-washing liquid in her own water at home and drinking it. She progressed to spiking her water with random chemicals she found at the lab, she told police.
The student said she did not have animosity toward her colleagues, and there was not a sense of competition as their projects did not overlap. She had insomnia and dizziness and felt a disconnection from reality starting in September, she told police.
The thought of her colleagues drinking the tainted water was "terrifying," she said, but she never checked on their welfare nor warned them. She was crying out for help, she told police, and she was sorry that things went so far, she said. The student was under the treatment of a psychiatrist and was being treated with antidepressants, She checked herself into the hospital after the investigation began and remained on a psychiatric hold.
Adding the chemical was a matter of opportunity -- that the water bottles were evident on desks -- and was not a matter of targeting individuals, she said. She also admitted to putting Trypsin into her own cell experiments as well as the colleague's, police noted.
Palo Alto Online and Palo Alto Weekly learned of the arrest in December but held the story at the request of the Santa Clara County District Attorney's Office. The DA was concerned about the mental state of the student. The DA's office no longer has concerns about its publication.
University officials asked that the name of the lab and the persons involved not be published due to privacy considerations for the victims.
"This was a very sad, heartbreaking and unfortunate circumstance for everyone concerned. The university has been providing support to the students involved, who have asked since the outset that their privacy be respected," Lisa Lapin, associate vice president of university communications, said in an email.
When the concerns were first brought to the university's attention in November, Stanford police launched an immediate investigation, as did the university. Police referred their findings to the Santa Clara District Attorney, Lapin said. An arrest was made as soon as the suspect was available to be arrested.
"This was an isolated incident, and there was at no time a threat to the campus community," she said.
Privacy laws -- the Family Educational Rights and Privacy Act (FERPA) and the Health Insurance Portability and Accountability Act (HIPPA) -- limit what the university can share, Lapin said.
The student's attorney may pursue an insanity defense. She is scheduled to appear in Santa Clara County Superior Court on May 15.