DES MOINES -- Mail processing centers in the Quad-Cities, Sioux City, Waterloo and Cedar Rapids soon will install systems designed to detect anthrax-tainted mail, U.S. Postal Service officials said Tuesday.

"Unfortunate as it is, we have to deal with this type of reality. It is a reality," said Richard Watkins, spokesman for the postal service. Officials unveiled the Biohazard Detection System, or BDS, at Des Moines' mail processing center, where detectors have been in place for 10 days.

BDS will be installed in local processing centers next month, he said.

"The nation's mail system is as safe as we can make it," Watkins said.

Federal officials scrambled to create a detection system after anthrax spores were mailed in envelopes to government offices and media outlets in October 2001. BDS, the product of a $500 million development effort, already has been installed in the nation's largest processing facilities.

It will be installed in 238 additional centers by year's end, Watkins said.

No anthrax incidents have been reported in local processing stations. But Steve Wenzel, who oversees plants in Iowa and Illinois, said suspicious letters are common.

"Probably weekly we have to deal with something we have to consider or treat as suspicious," Wenzel said. "Sometimes it's as innocent as someone putting spices or laundry detergent in the mail."

BDS is a large, white box connected to the mail sorting system. As letters flow through, the system takes hourly air samples.

If anthrax spores are detected, red lights flash and a siren sounds. Evacuation and decontamination would follow and emergency response agencies are notified in the event of an incident.

Officials said the system could be expanded in the future to detect other biohazards.

"The primary purpose of this is to make sure our employees are safe. The second priority is to make sure our customers are safe," Wenzel said.

Des Moines' central postal facility employs 1,100 people and handles 7 million letters each day. The other five local centers combined employ more than 1,000 people, officials said.

Todd Dorman can be reached at (515) 243-0138 or at todd.dorman@lee.net