A California engineer whose coworker was convicted of poisoning her water bottle with a toxic metal says the justice system failed her after a judge dismissed the felony case.
Rong Yuan, 50, began suffering severe symptoms in January 2017, shortly after starting work at Berkeley Engineering and Research, a forensic engineering firm also known as BEAR.
Yuan later used a hidden camera to record coworker David Xu, 41, secretly pouring a white substance into her water bottle. Police identified the substance as cadmium, a highly toxic heavy metal.
Xu was charged with felony poisoning in 2019 but never spent a day in jail. The case proceeded under former Alameda County District Attorney Pamela Price, who was later recalled by voters.
On Monday, a judge approved Xu’s petition to dismiss the charge after he completed his probation and fulfilled all court-ordered conditions, according to The Los Angeles Times.
‘We joined the victims to oppose the motion pursuant to Penal Code section 1203.4,’ Alameda District Attorney Ursula Dickson said in a statement Tuesday.
‘The court granted the motion over objections. We hope the survivors are able to continue healing, both emotionally and physically, from this shocking event.’
The dismissal means the conviction will no longer appear on background checks conducted by potential employers. It may only be considered if Xu is charged with another crime—a ruling that prompted Yuan to speak publicly about the case.
California engineer Rong Yuan, 50, says she feels failed by the justice system after a judge dismissed the conviction of the coworker accused of poisoning her water bottle for more than a year
Yuan began experiencing severe illness in January 2017 after taking a job at Berkeley Engineering and Research, also known as BEAR
Yuan’s coworker, David Xu, 41, was captured on a hidden camera pouring a white substance into her water bottle; police later identified it as the toxic heavy metal cadmium
‘The system failed me,’ Yuan told the outlet. ‘He didn’t stay in jail.’
‘To come out of my comfort zone, to be interviewed about you, to tell the public what kind of effect it had on my family and how broken the system is,’ she added, according to ABC 7 News.
‘I don’t think he deserves a second chance. A second chance for a lot to hurt other people, to make other people turning into victims.’
Almost 10 years later, Yuan continues to deal with liver and gastrointestinal problems after unknowingly ingesting the toxic chemical for more than a year.
Her parents traveled from China to the United States to help care for her as her health declined. They also consumed the contaminated water and tested positive for cadmium poisoning.
‘Cadmium will stay in the human body for a long time, damaging my health continuously for the rest of my life,’ Yuan told The Times. ‘My father died, my mom and I have health impacts.’
Asked by ABC what she wanted to say to Xu, who is now officially free of the conviction, Yuan said: ‘He’s a nobody. He’s a coward.’
‘Poisoning is not something like you suddenly got angry and lose control,’ she added. ‘It’s planned.’
Xu was charged with felony poisoning in 2019 but never served time behind bars. The case unfolded under former Alameda County District Attorney Pamela Price, pictured
On Monday, a judge formally approved Xu’s petition to have the charge dismissed after he completed his probation sentence and all required conditions
The shock ruling comes years after Yuan, a highly trained metallurgical engineer, first fell mysteriously ill in 2017, suffering extreme hair loss, relentless nausea and vomiting, and frequent trips to the emergency room.
Yuan feared she had stomach cancer, but tests ruled it out. Despite consulting doctors and specialists, she was left without answers and began to fear she was dying.
Her parents, terrified it could be terminal, came to stay with her. But a turning point came when her mother noticed a strange smell coming from the water bottle her daughter kept at work, which lingered despite repeated cleaning.
Yuan decided to buy a spy camera on Amazon and discreetly mount it on the wall beside her desk. She told ABC: ‘I never expected that I can capture anybody. It’s just an engineer’s routine. If you have some issue, you think about the root cause.’
In a chilling discovery, Yuan realized she had been poisoned by Xu, who allegedly resented her arrival at the company because he did not want to share his laboratory.
In one recording, dated March 4, 2019, Xu can be seen reaching toward the spot where Yuan kept her bottle before tipping the contents of a small white container directly inside.
At the time, she told The San Francisco Standard: ‘My blood was frozen. I almost died. I experienced death so, so close so many times. I cannot let him go.’ The same day, Yuan gave police the footage, prompting an immediate investigation.
Tests detected cadmium in Yuan’s water bottle and in blood samples from her and her parents, with the concentration in the bottle measuring 3.5 million times the federal government’s safe limit for drinking water.
Yuan, a highly trained metallurgical engineer (office pictured), began suffering from hair loss, nausea and vomiting and frequent trips to the emergency room in 2017
Xu allegedly resented her arrival at the company because he did not want to share his laboratory
‘Shocked. I don’t know why,’ Yuan told ABC after watching the damning footage.
In a research paper published last week, Yuan recalled how a series of alarming symptoms began in 2017, including nausea, dry heaving, migraines, shortness of breath and hair loss.
Violent bouts of vomiting soon began forcing her to take time off work, she said, and the ordeal continued into 2018. That year, she experienced severe vomiting and diarrhea after drinking water at the office.
‘On two occasions in November and December 2018, I brought water home from work, and my mother used that water to cook congee,’ Yuan wrote in the paper.
‘Following each meal, my entire family experienced acute onsets with violent vomiting, watery diarrhea, and profound weakness,’ she added.
Yuan said her father had been able to manage his hypertension and walk six miles a day before ingesting the water. In the years afterward, he suffered a series of strokes and died from heart failure last year, according to The Times.
In 2019, Xu was charged with premeditated attempted murder, causing great bodily injury under a special circumstance, and two counts of poisoning with an enhancement. He posted his $2 million bail.
He spent years out of jail as his case stalled in court, initially under house arrest with GPS monitoring until 2021. Over time, he was granted increasing freedom to leave home and spend time with his children.
The dismissal means Xu’s conviction will no longer appear on background checks for prospective employers and can only be used if he is charged with another crime
Price, who took office promising criminal justice reform, became the first DA in the county’s history to be recalled by voters in 2024 after critics accused her of being too lenient with criminals
In 2023, shortly after taking office, Alameda County District Attorney Pamela Price offered Xu a plea deal on one felony poisoning count, with no additional jail time, despite his initial exposure to a potential life sentence.
Price, who took office promising criminal justice reform, became the first Alameda County district attorney to be recalled by voters when she was ousted in 2024 after critics accused her of being too lenient with criminals.
Xu pleaded no contest, meaning he accepted the legal consequences of the charge without formally admitting guilt.
At his 2024 sentencing, the judge described the plea deal as ‘extremely generous, considering everything in this case,’ according to the San Francisco Standard.
The judge doubled Xu’s probation to two years, making him eligible to seek dismissal of his felony conviction under California law. His petition was granted on Monday.
‘No company can find the criminal record based on background search, now they also need to do an internet search,’ Yuan told The Times, fearing that Xu could secure a job at another company.
Yuan said she believes the cadmium exposure may have contributed to her father’s death from heart failure at 78, while she continues to suffer long-term health effects herself.
Cadmium has a half-life of 16 to 30 years in the human body, and prolonged exposure can cause cancer, organ damage and bone disease, according to a study by the National Institutes of Health.