Peter Zubke, 54, of Watertown, has been charged with a felony count of placing objects in edibles-domestic abuse and could be sentenced to up to 3 1/2 years in prison, the Fond du Lac (Wis.) Reporter said.
Zubke's wife said her husband was distraught because of their marital problems and had told her he could not live without her.
She said she noticed her diet soda and coffee looked and tasted different and saw weed killer stored under the kitchen sink. She told police she thought her husband had been putting the chemicals in her drinks for three to four weeks in June.
Zubke does lawn work for a living, but usually uses a different brand and keeps it in the garage, his wife said.
The Zubke's 15-year-old daughter told police that Zubke told her not to drink her mother's soda, police said.
Watertown police sent samples of the coffee, soda and herbicide to the Wisconsin Crime Lab for analysis.
Casey Collins, a state toxicologist, said coffee from a pot taken from Zubke's home contained chemicals found in the weed killer.
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