Stanford graduate student accused of poisoning lab mates

Woman allegedly spiked her lab mates' water with paraformaldehyde

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.

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34 people like this
Posted by Teach your children well
a resident of Midtown
on Apr 1, 2015 at 1:27 pm

[Post removed.]

6 people like this
Posted by CrescentParkAnon.
a resident of Crescent Park
on Apr 1, 2015 at 1:36 pm

What a dreadful experience to go through. Truly scary. I hope the full story comes out soon. You just never know about anything anymore. Do we now need fingerprint locks on our water bottles and lunch boxes? Sheesh!

13 people like this
Posted by Concerned
a resident of Another Palo Alto neighborhood
on Apr 1, 2015 at 1:52 pm

Re: Teach Your Children well

That is an exacerbated assumption. You don't know her and to speak ill of this student and her parents is wrong. It sounds as though she may have some mental health issues that need to be addressed. Shame on you for heaping on coals of fire.

My heart goes out to everyone involved. This pressure to exceed and be better than the rest has to stop in Palo Alto/Stanford. How many young people must suffer before we really stop and take a hard look? discussions, support groups and guards area ll fine, but we need some concrete movement.

9 people like this
Posted by Cynic
a resident of another community
on Apr 1, 2015 at 1:59 pm

I hope that this is an April Fool's joke, though in bad taste.

If not, it's all very sad.

21 people like this
Posted by Barb
a resident of Downtown North
on Apr 1, 2015 at 2:58 pm

Oh, Wow! According to "Concerned" we need yet another "movement" to keep students from poisoning their lab mates. I guess the Stanford student spending time poisoning her peers needs a shoulder to cry on? Good grief!

22 people like this
Posted by former Palo Altan
a resident of Community Center
on Apr 1, 2015 at 3:17 pm

One way ticket back to Singapore, sister. [Portion removed.]

2 people like this
Posted by Just off the boat
a resident of Crescent Park
on Apr 1, 2015 at 3:58 pm

[Post removed.]

25 people like this
Posted by Wife of M.D.
a resident of Palo Alto High School
on Apr 1, 2015 at 4:55 pm

No one-way ticket back to Singapore yet - she needs to serve time in prison here first. There is no way this can be an insanity plea. Singapore might not punish her.

The labs should have cameras. Pre-med and medical school students are notoriously ultra competitive. My husband's science experiment was ruined by someone so his results were incorrect.

19 people like this
Posted by CW
a resident of Crescent Park
on Apr 2, 2015 at 3:13 am

You should identify the defendant. And why did this case take so long to come to light? She was arrested in November.

8 people like this
Posted by musical
a resident of Palo Verde
on Apr 2, 2015 at 3:40 am

@CW, see final paragraph:

"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"

Identify the student and go to jail. Plus get sued for all you are worth.

What I don't understand is the statement: "This was an isolated incident, and there was at no time a threat to the campus community." The victims looked to me like part of the campus community. And there is no telling how far the perpetrator would have gone if not stopped. The article says this was not a case of animosity but rather a disconnection from reality.

14 people like this
Posted by Bian Mi
a resident of Atherton
on Apr 2, 2015 at 6:43 am

According to press reports, the student was sent from Singapore on a government A*STAR scholarship that is reserved for their very best and brightest. The students all go the top US universities, not so much on merit, but because the Singapore Government pays a full stipend, full tuition, and research funds for the host laboratory (that is, there is a financial incentive for the host university to accept these students). Remember, Singapore students top out standardized tests internationally but their students, like this one, do poorly once they have to compete in an academic environment that requires critical thinking instead of rote memorization. She was stressed out and depressed because she did so poorly at Stanford while she was a superstar student all her life in Singapore.

8 people like this
Posted by Wife of M.D.
a resident of Palo Alto High School
on Apr 2, 2015 at 9:34 am

Here's some articles with more info on her and a photo:

Web Link

Web Link

6 people like this
Posted by local
a resident of Another Palo Alto neighborhood
on Apr 2, 2015 at 9:41 am

Bian Mi,
That's changing. Friends from Singapore (visiting at Stanford) with a very creative child, described an education system that is now more about encouraging creativity than ours. They may not have propagated those changes through the system yet, but it's happening, and I know Singaporean parents care about it. I know people who are hired to go to Singapore to give workshops on creativity to university students in STEM and business fields.

Just because something sounds right, with a little to back it up, does not make it correct. A person who flails in a new situation is just as likely to try to rise to the occasion. The issue here was mental illness.

And getting in by a lower standard because some deep pocket is paying would have made her right at home in graduate school at Stanford....

9 people like this
Posted by Paly parent
a resident of Palo Alto High School
on Apr 2, 2015 at 9:54 am

This is in line with the cheating scandal. It is cheating pushed to an extreme form. Think about it. If someone cheats to get in (I am not saying it is the case of this particular student), it must be tough to survive academically at Stanford without further cheating... or trying to take out your fellow students.

I am now glad that my children never even wanted to go to Stanford. It sure sounds like a very unhealthy environment.

8 people like this
Posted by Stanford science rules
a resident of Stanford
on Apr 2, 2015 at 10:09 am

"Pre-med and medical school students are notoriously ultra competitive."
She was a graduate student. Was your husband ultra competitive

Paly parent--perhaps you are not familiar with what graduate students in research labs focus on--there are some classes in the early days, but the main period of time is spent on a research project--which involves bench work.
I am not sure why you are trying to extrapolate it to the cheating issue.
So, we have one graduate student out of I do not really know how many over the years who tries to poison some of her fellow students and you claim that the environment at Stanford is "unhealthy"???

10 people like this
Posted by AlexDeLarge
a resident of Midtown
on Apr 2, 2015 at 10:10 am

Insane? Perhaps. Malevolent, for sure.

6 people like this
Posted by Wife of M.D.
a resident of Palo Alto High School
on Apr 2, 2015 at 10:42 am

@Stanford science rules: Sure, my husband is ultra-competitive - one has to be to survive the rigor of pre-med. Many start out pre-med but fail. But he would NOT cheat to win - or in this case, try to knock-off the competition! And there are many others like him who have integrity. Let me also add that we are Chinese, so don't go stereotyping that it's the Asian culture because in general, Asians do not break the law (check the prison pie charts). There were pre-meds who would not share any info with others, such as internships, homework, advice, because of their competitiveness, or even knowingly give incorrect advice just to screw the competition.

9 people like this
Posted by Stanford science rules
a resident of Stanford
on Apr 2, 2015 at 11:26 am

WIfe of MD--do not accuse me of stereotyping asians, which I have not done. Also as I have noted--she was not a med student or a pre-med student, she was a graduate student--big difference.
But I am glad to see that a PA high school student has married a high powered MD.

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