UPPER GWYNNED TOWNSHIP, Pa. (CBS) — A chemist is accused of stealing potassium cyanide from a laboratory in Montgomery County.

Montgomery County District Attorney Kevin Steele says 60-year-old Richard O’Rourke of Warrington stole nearly 220 grams of potassium cyanide from the Merck & Co. laboratory in Upper Gwynedd Township in December.

READ MORE: CBS3 Mysteries: Father Of Man Who Marked Grim Milestone For Philly Wants Son To Be Remember More Than Number

Princeton Professor Cancels Course On Free Speech After Using Racial Slur In Class During Exercise

Police were notified on Dec. 16 by Merck that O’Rourke allegedly stole potassium cyanide from the poison cabinet at the laboratory.

According to police, a longtime senior chemist saw O’Rourke, who is not required to handle the poison, pour potassium cyanide into a beaker and then into a Nalgene bottle on Dec. 14. He was then seen leaving the premises.

READ MORE: Upper Darby Chiropractor Charged With Sexually Abusing 9-Year-Old Girl During Exam

Police say an investigation revealed that O’Rourke was planning to use the cyanide to poison rodents on his property, but when he found out that he was under investigation, he dumped the chemical into a stormwater inlet in the area of County Line and Street Roads on Dec. 15.

The Pennsylvania Department of Environmental Protection then began monitoring the water supply for possible signs of the chemical and toxicity as both Aqua PA and the Philadelphia Water Department intake facilities could have been affected. No evidence was found of a toxic impact after the PADEP and the water departments remained on high-alert status for two weeks.

14 Worms Pulled From Woman’s Eye After Rare Infection

O’Rourke has been charged with causing or risking catastrophe, theft, receiving stolen property and recklessly endangering another person.

MORE NEWS: Philadelphia Business Owners Seeing Uptick In Brazen Thefts

O’Rourke posted his $35,000 bail and was released. A preliminary hearing is scheduled for March 6.