A man suspected of sprinkling a combination of mouse poison, hand sanitizer and water on produce in grocery stores in Michigan was arraigned on Thursday in district court in Ann Arbor, Mich., on four felony counts of poisoning food and drink.

The man, Kyle Andrew Bessemer, 29, had been arrested after he was identified by members of the public when images from surveillance video showing him in a grocery store with a red shopping basket were published online, the F.B.I. and the local police announced on Tuesday.

The authorities said Mr. Bessemer, of Ann Arbor, had intentionally contaminated food in open food bars and produce sections by spraying the items with the mixture at stores, including a Whole Foods Market, a Meijer and a Plum Market, over the last two weeks.

It was not clear if anyone had been sickened by the poison or how it had been detected. The authorities did not provide a motive.