The 26-year-old man has been in a coma ever since the poisoning in 2016 with a man, named only as Klaus O, found guilty of attempted murder last year.
The man’s sandwich was poisoned by a co-worker
The 26-year-old has been in a coma since the poisoning in 2016.
His death was confirmed on Thursday by the state court in Bielefeld, which convicted the suspect in the case last year.
During his trial a psychologist said the poisoner, identified only as Klaus O. for privacy reasons, came across like a researcher who was trying to see how different substances affected rabbits”.
The poisoned man’s parents spoke about his suffering during the trial last year, German news agency dpa reported.
A 57-year-old Klaus O. was sentenced to life in prison last March after the court found him guilty of attempted murder.
The defendant, who has appealed against the verdict, peppered co-workers’ food with mercury and other substances over several years, leaving one in a coma and two others with serious kidney damage.
The case came to light after a colleague at a metal fittings company in the town of Schloss Holte-Stukenbrock, in north-western Germany, noticed a white powder on his lunch.
He was arrested in May 2018 after surveillance video showed him putting a suspicious powder on a colleague’s sandwich at their workplace.
Following his trial in March last year a judge ruled Klaus O would not have his sentence reduced because he was a “danger to the general public”.
During a search of the suspect’s apartment, police found toxic chemicals such as mercury, lead, and cadmium, they said.
Further investigation uncovered 21 cases, dating back to 2000, of employees at the same company who had died of heart attacks or cancer shortly before retiring. Experts concluded that heavy metal poisoning could have been the cause of the illnesses that led to those deaths.
The suspect’s motive was not clear because he remained silent about the allegations, the police said.
The renaissance castle and moat in Schloss Holte-Stukenbrock, North Rhine-Westphalia, Germany
Tests identified it as lead acetate and mercury, almost tasteless substances that if ingested could lead to serious organ damage.
Exposure to mercury can cause a number of health issues including skin, neurological and kidney problems.
Most exposure comes from eating fish, coal and gold mining, or dental fillings.