"The Postal Service is facing an unprecedented threat," said Rep. Henry A. Waxman (D-California), the ranking minority member of the committee. "Bioterrorists are poisoning innocent Americans with anthrax by taking advantage of the anonymity of the mail." 
Waxman is proposing the implementation of a two-dimensional barcode "stamp" that would contain the sender's identity as well as the date, time and place the postage was paid. The technology is currently used by companies that provide Internet mailing services, such as Stamps.com . 
He said the particulars of the proposal -? including costs and the effect on stamp machines -? still need to be hashed out. 
A Postal Service spokesman refused to comment on the tracking proposal but allowed that the agency was "aggressively looking at virtually everything that's out there" to increase security. He added that mail-sorting technologies -? such as barcodes -- can be implemented unilaterally by the USPS without congressional approval. 
The USPS responded to the anthrax attacks by irradiating mail, but Waxman and others say the method is insufficient. Because irradiation equipment is costly, it has only been dispatched to a few undisclosed postal service facilities. The bulk of the 680 million pieces of mail delivered each day by the USPS is not sanitized. 
Irradiation, which consists of bombarding objects with high energy electrons that break up the bacteria's DNA and kill it is routinely used to sterilize food products such as meat. 
But the process can also destroy the mail - earlier this month, 90 lbs. of envelopes and magazines burst into flames at a New Jersey postal facility when the material overheated. Irradiation also harms electronics, exposes film and weakens prescription drugs, said Maynard H. Benjamin, president of the Envelope Manufacturers Association , a trade group representing the makers of 93 percent of the envelopes manufactured and distributed in North America. 
Benjamin, who attended closed-door meetings with the USPS and Waxman this month, has suggested the agency consider "fiber fingerprinting," which identifies correspondence by the unique characteristics possessed by each piece of paper. 
But the ultimate goal of any technology adopted by the USPS should be to identify the people sending mail, he said. 
"If you look at Federal Express or UPS, the reason there have been minimum successful threats to them is that everything they have is traceable and trackable," Benjamin said. 
Privacy advocates say that traceable mail would stifle whistle-blowers and government critics. Furthermore, they argue, the system could backfire. 
"You'll have the same fraudulent problems that you have with IDs and credit cards now," said Lauren Weinstein, the moderator of the Privacy Forum . "The bottom line is that the bad guys are going to find a away around it. What if they steal your stamps, and you get framed for something you didn't send?" 
Weinstein said that proposal could further harm the precarious financial health of the USPS, by pushing more consumers to opt for e-mail over snail mail. 
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