MIDTOWN, Manhattan (PIX11) — A Queens man was charged Wednesday with trespassing in a Midtown hotel where a worker was exposed to what was initially feared to be an explosive substance, officials said.

John Taddei, 55, is accused of theft of services and criminal trespass, but was not immediately charged with any further crimes after the substance was found to be inert, according to authorities.

The scare began around 1:30 p.m. Tuesday when a worker at the Park Hyatt New York on West 58th Street near Seventh Avenue found the white, powdery substance while cleaning out a vacant room on the 11th floor, police said.

The worker, 38, began feeling nauseous and dizzy shortly after coming in contact with the substance, and was taken to an area hospital in what officials described as stable condition.

Though the substance had already been cleaned, FDNY responders swabbed surfaces in the room and found possible traces of an explosive, authorities said in a Tuesday evening briefing. The NYPD then evacuated the floor out of what NYPD Assistant Chief James McCarthy called “an abundance of caution.”

Further tests found no other traces of hazardous substances, leaving it immediately unclear what sickened the worker. It was ultimately determined that the substance was inert, and 11th-floor guests were allowed back into their rooms. Officials did not disclose what the substance is now believed to be.

Subsequent investigation led police to believe that a family previously staying in the room misplaced one of their keys while checking out on Sunday. 

Taddei, of Kew Gardens, is accused of then trespassing. An online court database did not contain information on the case as of Wednesday afternoon.