The Ames Police and Fire Departments responded to two calls for hazardous materials found Tuesday.

The calls are the first and second of their kind received this year, although there is no known relationship between the incidents.

At 9:47 a.m., the ISU Police Department received a call from staff in Alumni Hall saying that an employee sorting mail noticed a powder coming out of an envelope, said ISU Police Capt. Gene Deisinger.

“During the initial investigation of the envelope and powder, there were some aspects of the envelope that made it look suspicious,” Deisinger said. “It was later determined that the powder was a common household cleaner and did not pose a risk of contamination to those who had been exposed to it.”

The powder came through the mail contained in a business-sized envelope, according a University Relations e-mail. The envelope was addressed to Iowa State’s Admissions Office and was opened by an automated machine. A mailroom employee, who saw the powder spill out of the envelope, and two other ISU employees were potentially exposed to the powder.

“The way the envelope was addressed was out of the ordinary,” Deisinger said, declining to go into detail.

Once the powder was identified as non-hazardous, the three people were notified and released from quarantine.

The ISU Environmental Health and Safety and the Ames Fire Department Hazardous Materials Unit also responded to the incident.

When the investigative teams arrived, employees were already outside the building.

“Since there was no hazard, the building was released back to the departments that occupy it for them to decide what to do,” Deisinger said. “Since the employees thought the investigation would take longer than it actually did, they left the building.”

Later Tuesday afternoon, a mailman found another suspicious substance, described as a yellowish powder, in the mailbox of an apartment building at 124 Hyland Ave.

Owners of the mailbox could not be reached for comment.

The Ames Fire Department received a call at 3:14 p.m. and responded to the scene.

“We responded to a report of possible unknown substance,” said Ames Fire Department Capt. Brian Sorenson. “We took a sample of it and found out it was not hazardous, so we cleaned up the area.”

Ames Fire Chief Clint Petersen said the Des Moines Hazardous Materials analysis determined it to be a “benign substance.”

The substance was sent to the University of Iowa Hygienic Laboratory, where it will undergo further analysis, Petersen said.

“I have no reason to believe there is a connection between the two cases,” Petersen said. “In the last year, we have not responded to any calls like these today.”

Michael Wichman, environmental health program manager at the laboratory, said the preliminary test has been completed and the powder was calcium carbonate, a low level detergent. A preliminary chain reaction test was conducted to test for anthrax, he said.

“We have another way to test it and to confirm it’s not anthrax; that takes 72 hours,” Wichman said.

Many students and Ames residents walking along the street noticed police cars and fire and rescue vehicles and stopped to watch the commotion.

Brooke Westphal, senior in music, lives in the building where the substance was found and said she was in her apartment on the phone when she saw the police officers in the parking lot.

She went outside to see what was happening and was then evacuated.