Berkeley Engineer Seeks Dismissal of Poisoning Conviction

A California engineer convicted of poisoning a coworker faces renewed public scrutiny after his accuser released hidden-camera footage as he sought dismissal of his felony conviction. Rong Yuan released the recordings showing David Xu apparently adding a substance to her water bottle, while prosecutors opposed his request in Alameda County court on Monday.

According to prosecutors, Xu, a former senior materials engineer at Berkeley Engineering and Research, poisoned Yuan's food and water with cadmium, a toxic heavy metal, over more than a year between 2017 and 2019.

Xu initially faced charges including premeditated attempted murder and two felony counts of poisoning, according to the San Francisco Standard. He ultimately pleaded no contest to one count of poisoning under a plea agreement that included one year of probation.

At Xu's 2024 sentencing hearing, the judge extended his probation to two years, describing the original agreement as unusually lenient.

"Extremely generous, considering everything in this case." The judge characterized the plea agreement this way during sentencing, according to the source report.

Yuan told the San Francisco Standard that releasing the footage was her final attempt to seek accountability through a legal system she believes failed her.

"Last resort," Yuan said of her decision to release the hidden-camera recordings, according to the San Francisco Standard.

California law requires judges to grant certain requests to dismiss felony convictions when defendants satisfy the applicable probation conditions, despite objections from prosecutors. Xu completed his probation in March, and the requested dismissal would not erase the conviction from his record.

Yuan joined Berkeley Engineering and Research in January 2017. She described an initially tense encounter with Xu, alleging that he told her she could not use the company's material characterization laboratory.

"I just decided I will never overlap with him," Yuan said, recalling her reaction to the encounter.

She explained that she intended to avoid further conflict while continuing her work at the company.

"I'll just simply do my work, and he can do whatever he wants." Yuan described her decision to keep her distance from Xu.

Within weeks, Yuan began experiencing symptoms including dry heaving and hair loss, according to her account. She recalled a particularly frightening episode in July 2017 after taking several sips from her water bottle.

"I began to feel like I was dying." Yuan described how she felt after drinking from the bottle.

By late 2018, Yuan had repeatedly visited the hospital. In an email dated November 27, 2018, she told colleagues she was vomiting and would not come to the office.

"You should work from home until you feel better. No reason to rush in," Xu responded to Yuan's email, according to the account published by the San Francisco Standard.

Xu also suggested a possible environmental explanation for the illness in the same email exchange.

"I think BEAR is moldy." Xu wrote this in his response, referring to the workplace.

In January 2019, Yuan experienced another alarming episode after drinking from the bottle on her desk. Her mother also tasted the water and noticed a sour flavor, prompting Yuan to suspect that someone was tampering with it.

"I'm going to die." Yuan recalled her fear after drinking from the bottle in January 2019.

Yuan ordered a hidden camera and installed it on her desk on February 11, 2019. According to the footage description, Xu approached the area where her water bottle was located at 11:04 a.m. that day.

A second recording, dated March 4, 2019, appeared to show Xu pouring an unidentified substance into Yuan's water bottle.

"My blood was frozen," Yuan said after watching the recording.

She described the footage as confirmation of how close she believed she had come to dying during the episodes.

"I almost died. I experienced death so, so close so many times. I cannot let him go." Yuan made the statement while explaining why she decided to release the video.

Fox News Digital reported that it contacted Xu's attorney for comment. The source article did not include a response from the attorney.