Even as it turns to the latest technology to keep mail bacteria-free, the United States Postal Service is warning Americans to wash their hands after handling their mail to avoid any possibility of errant anthrax contamination.

Thursday, the post office was sanitizing truckloads of mail shipped from Washington with electron-beam technology. Deborah Willhite, a senior postal vice president, said the machines would be used at other facilities soon and said masks and gloves were being handed out to over 800,000 postal workers.

Nonetheless, postal officials urged Americans to wash up after handling mail — admitting they cannot guarantee its safety.

"We have debated internally since this began whether we could just stand and bald-face say, 'Don't worry, your mail is safe,'" Willhite said.

"We're not going to lie to the American people, who have sustained us for 227 years. At this point in time, the mail has a potential risk," she said, adding: "You know, on the risk management scale of life, the mail is pretty low."

President Bush released $175 million to help the agency, and the postal governing board authorized an additional $200 million in emergency spending to help pay for equipment and other safety measures.

More electron-beam sanitizing equipment is expected to arrive next week, using technology similar to that used to sterilize medical equipment and food.

"Even as we speak, we are taking tractor-trailers of mail to be sanitized as a demonstration project to see how that process would work," Willhite said.

"We need to make sure that while we are sanitizing the mail we are not destroying people's keepsakes. If it's going to ruin your grandma's homemade cookies, we want to let you know," she added.

The post office also reported that it has bought a 90-day supply of gloves made of Nitrile, a high-grade plastic, for use by postal workers sorting the mail.

And the agency is obtaining face masks for workers that can screen out 95 percent of bacteria, including anthrax spores.

The gloves and masks will be optional for postal workers but the agency wants to have them available to any of the thousands of workers who may want to use them. At least some federal mailroom workers already have received advanced breathing protection.

The agency also has started using a vacuum cleaning system on its machines — instead of blowers that could spread anthrax spores — and switched to anti-bacterial cleaning solutions.

Two postal workers and a Florida man have died and others have been sickened by contamination since the anthrax-by-mail crisis began.

The contamination has led to anthrax testing and provision of antibiotics for thousands of postal workers in Washington, New York and New Jersey as well as some members of the media and others who had spent time in Washington's now-closed Brentwood mail facility.

On Wednesday, employees of organizations that bring large shipments of bulk mail to the Brentwood center were added to the list of people being tested. She said that includes about 200 workers from organizations such as the Humane Society of the United States and the International Monetary Fund.

Postmaster General John Potter said the agency is "taking concrete steps immediately to protect employees and the public through education, investigation, intervention and prevention."

But Sen. Charles Grassley, R-Iowa, questioned whether the Postal Service and the Centers for Disease Control and Prevention did enough to protect postal workers and is doing enough to screen the mail still being delivered in the Washington area. The agencies have been criticized for waiting several days before testing people for anthrax at the contaminated Washington distribution center.

"It is critical that your agencies retrace your steps to ensure that no one else dies from this scourge," Grassley wrote to Potter and CDC director Dr. Jeffrey Koplan. "It is up to public health authorities and the U.S. Postal Service to demonstrate that mail delivered in Washington, D.C., is not dangerous."

Tom Ridge, the newly named director of homeland security, said public health officials didn't make the safety of postal workers a lower priority.

"I'm absolutely positively, 1,000 percent convinced that they weren't looking at the collar of the shirts, whether it was a white collar or a blue collar challenge," Ridge said. "They were looking at a medical challenge."

The Postal Service is at war, Potter has said, insisting that the agency will continue to deliver the mail.

The Associated Press contributed to this report.