The Ogle County Coroner has released the findings of an autopsy done on the wife of a Nobel Prize winner found dead outside an Ogle County landfill earlier this month.

Sumire Negishi, of West Lafayette, Indiana, was found dead near the Orchard Hills landfill on March 14. An autopsy completed on her lists her cause of death as exposure and hypothermia.

An investigation by the Ogle County Sheriff’s Office determined her death to be accidental and no foul play is suspected.

Sumire was found shortly after sheriff’s deputies found her husband, Eiichi Negishi, 82, wandering along Route 251 not far from the landfill. The two had been reported missing out of Indiana a day earlier.

Eiichi Negishi is a Nobel Prize winner in chemistry. He received the award in 2010 for the discovery of “Negishi Coupling” in organic synthesis. He spent most of his career at Purdue University.

In a statement, Purdue President Mitch Daniels said Sumire Negishi suffered from Parkinson’s.