Engineer David Xu pleads no contest to colleague poisoning

David Xu, a metallurgist at Berkeley Engineering and Research in California, pleaded no contest to a felony count of poisoning his colleague Rong Yuan. Xu was captured on hidden camera tampering with Yuan's water bottle using cadmium, a toxic heavy metal, over a period of nearly 18 months from 2017 to 2019.

Yuan experienced severe health issues during this time, including severe vomiting, which required emergency treatment. The poisoning was uncovered after Yuan installed a hidden camera at her desk, revealing Xu's actions.

Laboratory tests confirmed cadmium levels in her water bottle at up to 3.5 million times the federal limit for drinking water. Xu was arrested in March 2019 on charges of attempted murder, which were later dropped.

In March 2024, he was sentenced to two years of probation and ordered to pay $7,058 in restitution, significantly less than the nearly $500,000 Yuan sought. Yuan continues to suffer long-term health effects and published a research paper on the consequences of the poisoning.