HOUGHTON — Police are still actively investigating the 2015 death of a Houghton woman whose poisoning is being considered a homicide. 

Janel Sturzl, 31, died of thallium poisoning on Dec. 22, 2015. The metal, formerly used for pest control, was banned in the 1960s. It has no odor, color or taste. 

Sturzl had fallen ill in October 2015 and sought treatment. That November, the Mayo Clinic in Rochester, Minnesota determined she was suffering from thallium poisoning. 

Police announced the case was being investigated as a homicide in August 2016. Houghton Police Chief John Donnelly said the high level of the toxin in her system wouldn’t have come from accidental exposure. No other cases were reported in the area at the time, eliminating a wider contamination.

“When there’s only one person with a high level of toxicity in her system, it leads us to wonder how it got there,” he said. 

Houghton Police Department has been working with the Michigan State Police, FBI and Western Upper Peninsula Health Department. 

Anyone with information is asked to call the department at 487-5912.