Detroit's Fire Department sent a hazardous materials team to the Detroit Medical Center campus late Tuesday morning to investigate reports of a strong odor at Brush and Canfield Streets.
According to WXYZ, a passerby reported an odor that "smelled like nail polish with a noxious hint to it," around 9:30 a.m.
Detroit Fire Department spokesman Lt. Gerod Funderburg said investigators had found traces of methane gas, but stressed that there was no cause for concern.
"There is no problem," he said. "Hazmat was just called as a precautionary method."
Funderburg did not know what caused the smell, but said it was coming from a sewer. He said the hazmat team was waiting for the Detroit Water and Sewerage Department to clean out the system by flushing the sewer line