Concrete sealing work behind the hospital was the source of noxious fumes at Sparrow Hospital in Lansing, Mich., according to an article on the Lansing State Journal website.
The fumes were detected near an operating room area, but the hospital said patients weren’t exposed anything toxic.
Officials added that those affected by a low, non-toxic level of fumes were treated for symptoms.
All hospital rooms affected by the fumes were cleaned and have air quality verified before they are re-opened for patients.