An Arkansas man who produced jars of the lethal poison ricin on his property with the intention of setting traps for trespassers was sentenced to eight years in prison for possessing a biological agent, prosecutors said.

The man, Jason Kale Clampit, 44, of Winslow, Ark., who made his own ricin, a poison that is extracted from castor beans, was sentenced on Friday to 96 months in prison without the possibility of parole, the U.S. attorney for the Western District of Arkansas said in a statement.

According to court documents, a citizen, who was identified as Mr. Clampit’s sister, made an anonymous tip to the Washington County Sheriff’s Office in January 2024 and said that Mr. Clampit was manufacturing ricin and may have poisoned his mother with the substance in Winslow.

Ricin (pronounced RICE-in) is a chemical that is present in castor beans, which have been cultivated for millenniums for their oil. Ancient Egyptians used castor oil for its moisturizing and laxative effects, and the toxicity of castor beans has been long known. Ricin is a waste product left over from castor oil extraction.

In the 1940s, the U.S. military experimented with using ricin as a possible warfare agent, according to the Centers for Disease Control and Prevention, and groups have been accused of plotting terrorist attacks with the substance.

“Exposure to even a small amount of ricin may be fatal,” according to the C.D.C.

Mr. Clampit’s sister told the authorities that he had talked about knowing how to perform plant extractions, according to court records. His girlfriend also told the authorities that he had listened to podcasts about toxins and had researched them online.