A scientist at the University of Wisconsin-Madison has been accused of poisoning a co-worker’s shoes and water bottle after being denied a promotion.
University police took Makoto Kuroda, a 41-year-old employee at the School of Veterinary Medicine’s Influenza Research Institute, into custody on Friday April 10 after the department became aware of a “safety issue” involving the scientist and another employee.
Kuroda is accused of “intending to cause harm to a co-worker with whom he had a dispute by adding small amounts of common laboratory chemicals to the co-worker’s water bottle and personal belongings,” the university said in a press release last week, citing a criminal complaint.
The co-worker told police that he had noticed a “strange order” coming from his plastic water bottle on his desk on Saturday, April 4, according to a state criminal complaint.
The employee said that when he drank from the bottle, it tasted bad, prompting him to spit the water out.
Two days later, the employee noticed the same odor coming from his lab shoes, which are kept in his office, the complaint said.
The employee said he didn’t have any issues with anyone at work. But when police questioned Kuroda, he said he had been upset with the employee, who he had worked with for about five years, for quite some time “due to his behavior at work,” according to the complaint.
Kuroda said his co-worker had received a promotion, and he had not. The scientist said he felt his colleague thought he was better than him once he was promoted. Kuroda also aired other grievances against his co-worker, including that he would not wear a lab coat when supervisors were not around.
Another colleague shared an email with police, in which Kuroda admitted to the poisoning, writing, “I did it. I have also informed the person himself. I am very sorry,” according to the complaint.
Kuroda had mixed the substance paraformaldehyde and Trizol, a chemical used to separate RNA, and put about .5 microliters of the blend in his co-worker’s water bottle, the complaint said. He also put about 1.5 microliters of the mixture into each of his colleague’s work shoes, according to the complaint.
The scientist expected his co-worker to get sick from the mixture, the complaint said.
Kuroda explained to police that even 1 microliter of paraformaldehyde would cause irritation and a rash in the mouth and throat if consumed. He also said a rash would form if someone put shoes on that were soaked with the paraformaldehyde and Trizol mixture.
The scientist has been charged with second-degree recklessly endangering safety and tampering with household products. If convicted, he may be fined up to $25,000 or imprisoned for up to 10 years.
Kuroda has been placed on administrative leave and the university is conducting a workplace investigation. His research privileges have been revoked, and he no longer has access to university assets.
Information about Kuroda’s legal representation was not immediately clear.
