Emergency workers and ambulances are staged in the back parking lot at the Monmouth County Courthouse in Freehold, N.J. Monday.
New Jersey officials will conduct air-quality tests Thursday and Friday at the Monmouth County Courthouse to try to identify the mysterious odor which sickened dozens of workers over the past two weeks.
The Freehold courthouse remains closed while officials from the state Department of Health and Senior Services investigate.
All previous testing has been negative, authorities said, including testing done on Tuesday night for common allergy-causing substances.
The courthouse has been closed since Monday afternoon, when 25 people were hospitalized and roughly 40 more were treated for symptoms that included nausea, skin rashes, breathing difficulties and chest pains.
That outbreak came after 17 staffers had experienced similar symptoms on Friday.
"The safety, health and well-being of the employees and those who visit the courthouse are our top concern," County Administrator Teri O'Connor said Wednesday. "This final testing will tell us what's wrong, or at the very least alleviate any lingering fears people may have about the health of the building."
Once the tests are complete, the building will be cleaned again, and officials will decide when to reopen the courthouse.
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