The Centers for Disease Control and Prevention reported Thursday on the continuing investigation of a neurological illness reported by pork plant workers in Minnesota and Indiana and gave the condition a name: progressive inflammatory neuropathy, or PIN. Workers at Quality Pork Processors in Austin, Minn., and at a pork plant in Indiana have reported symptoms including fatigue, numbness and tingling in their arms and legs.

Officials in Minnesota said they want to investigate QPP workers going back a decade, to when an air-compression system was installed to remove brain tissue from pig heads, the Minneapolis Star Tribune reported. The question is whether pig brain tissue was inhaled by workers who became sick after it was liquefied during removal by the air-compression system and sprayed into the air as droplets.

Both plants have stopped using the process to remove pig brains.