However, Michael Whorf, spokesman for the Kern County Sheriff's Department, said that the initial swabs of the inside of the bag and the surface of one of five bottles tested positive for TNT and TATP explosives.
"We're continuing to investigate to try to figure out what's causing these test results to come up the way that they have and to determine what exactly is in the bottle, and investigating his story, too," Whorf said in a news agency report.
31-year-old Francisco Ramirez was detained of Tuesday, Jan 5 after his bag tested positive for unkowm Transportation Security Administration (TSA) found his bag testing positive for an unkown material.
The two screeners who opened bottle had to be taken to a hospital as they complained of nausea after smelling a strong chemical odour from the bottle.
Ramirez who claims to be a gardener form Milwaukee has been put aboard the flight from Bakersfield to Milwaukee.
Flights in Meadows Field Airport in the central California city of Bakersfield was suspended for two hours after Ramirez's bag tested positive for unknown chemical.
But no explosives were found in the bag.
Investigators are trying to find out the truth behind Ramirez's claim that he was visiting relatives in California.