BLOOMINGTON - About 10 staff members of Carle Clinic became ill on Wednesday as Carle continued to investigate what caused unidentified fumes first detected in one area of the clinic on Tuesday afternoon.
The irritant and the symptoms experienced by the staff members on Wednesday were not as strong as what was experienced Tuesday afternoon, Carle spokeswoman Stacey Shangraw said. All told on both days, about 40 people became ill.
"It is dissipating," she said of the fumes.
The area affected was the ear-nose-and-throat department of the clinic, 1701 E. College Ave. As a precaution, that department was closed at noon Wednesday.
Patients scheduled for the afternoon rescheduled their appointments. That department already was to be closed today and Friday.
"We are increasing the air exchange through our internal ventilation system, which should clear out the problem by Monday, when that area is scheduled to see patients," Shangraw said.
The rest of the clinic remained unaffected and in full operation, she said. That included the walk-in urgent care clinic, Convenient Care.
The 10 staff members on Wednesday experienced headaches, body aches, and dry, scratchy throats, Shangraw said. On Tuesday, the people who became ill - mostly staff members but a few patients - reported more severe headaches, body aches and dry throats in addition to a metallic taste and some vomiting, she said.
The building was briefly evacuated mid-afternoon Tuesday, but firefighters said they couldn't detect the cause of the irritations.
A heating, cooling and ventilation contractor gave the heating and ventilation system a clean bill of health, Shangraw said.
Late Wednesday afternoon, an independent environmental professional from Champaign -- joined by Carle's building services director from Urbana -- did an indoor air quality evaluation and found nothing harmful in the air, Shangraw said.
"We don't know what it (the cause) is, but we know what it's not: It's not Freon and it's not a gas leak," Shangraw said. "We're pretty sure it was a blast of something."