A laboratory employee at the University of Wisconsin has been accused of attempting to poison a colleague’s water and personal belongings, allegedly driven by long-standing resentment over workplace issues.
According to a criminal complaint filed in Dane County, 41-year-old Makoto Kuroda is facing charges including reckless endangerment and product tampering after allegedly contaminating a co-worker’s drinking water and lab shoes with hazardous chemicals.
The victim, identified as TM, became suspicious on April 4 after noticing a strange smell and unpleasant taste in his water bottle. After spitting the liquid out, he later detected the same odour in his office, which was traced to his work shoes kept on-site.
Investigators allege Kuroda later admitted his actions, telling TM directly, “I did it.” Police say he confessed to using a syringe to inject a mixture of paraformaldehyde and trizol into the bottle and the shoes during a return visit to the lab the following evening.
Kuroda reportedly told authorities that frustration had built up over several perceived slights, including a missed promotion, workplace habits he found irritating, and minor interactions that compounded over time. He described the pressure as escalating until it led him to act.
The complaint states Kuroda researched toxic quantities of the chemicals online before carrying out the act. He allegedly believed the amount used would cause illness such as vomiting and dizziness, though not be fatal.
Authorities say the investigation is ongoing.
