>>Irradiating Mail Could Damage Shipped Goods
By Amanda Onion ABCNEWS.com
If the postal service begins irradiating mail, the technology could kill more than anthrax.
It makes hamburgers safe to eat and could soon make mail safe to handle.
But some have questioned whether the electron beam irradiation systems the United States Postal Service bought late last week to help prevent the spread of anthrax through the mail could also endanger some commonly shipped items, including seeds, film and electronics.
According to radiation safety experts, the answer is yes.
"You would not want to put film or seeds anywhere near it," said Andrew Karam, a radiation safety officer at the University of Rochester in New York. Some electronic equipment, including personal digital assistants and computers, could also be affected, he said.
"Germs take a lot more radiation to kill. That means this would be a heavy dose."
Tests Will Determine Effects
The Postal Service announced on Friday it's spending about $40 million to buy eight electronic pasteurization systems from Titan Corporation, a San Diego-based company that owns the so-called SureBeam technology. These irradiation units generate controlled, non-radioactive electronic beams to kill harmful bacteria. The technology is considered safer than using radiation from radioactive elements, which are more difficult to contain.
It's a technology that's been used for more than three years to treat meat and produce and it has long been applied to sterilize hospital equipment. Now it will be applied to letters and packages sent through the mail to stop the spread of biological agents.
The Postal Service says the equipment is being installed in "targeted areas" of the postal system and the first units are being delivered to the Washington, D.C., area. The postal service may buy as many as 12 units to install in mail processing centers across the country.
In a statement, the Postal Service said it is conducting research "to ensure that the technology used for sanitizing equipment does not cause other problems by damaging sensitive material."
Still, the prospect has some companies a little uneasy.
Seeds, Film, Technology Not Safe
"Depending on how high the radiation levels are, we might switch to a different carrier," said Colby Wolfe, a spokesman for Burpee Seeds, the largest seed shipping company in the United States, based in Warminster, Pa.
Ed McCabe, president of Mystic Color Labs, a Web-based photo development company that ships more than 3 million packages of film every year, is also unsure about possible implications.
"It's very much in the air," he said. "We're trying to see just what the machines will or will not do to our film."
Many questions remain about how widely the irradiation will be applied and how much some items will be affected. But Wil Williams, a spokesman for the Titan Corporation, is already sure of a few things: The machines can treat about 1,000 pounds of mail per hour. If used on packages containing electronics, the electron beams could damage the equipment; it could also expose unexposed film, damage plants and possibly inhibit seeds from germinating.
He claims it's unlikely the technology will be applied to packages holding such goods.
"No one is making any claims this will be used to process everything," he said. "The point is not how the technology could damage mail, but how it could secure U.S. mail and get it back to normal," Williams said.
Bacteria Require a Heavy Dose
Here's how the technology works: A power source pumps volts of electricity into a cathode ray tube where an electromagnet converts the electricity into a beam of electrons. The electrons are kept in a straight line by passing through a vacuum and then a scanner directs the beam onto the items passing by on a conveyor belt.
The beams penetrate the cell walls of any living thing on the items, including those of bacteria, and break down the organelles inside. The electrons can also stimulate chemical reactions that produce tiny, energetic short-lived molecules known as free radicals that can break down DNA.
"The beam of electrons, for all the world, act like a machine gun shooting bullets," explains Doug Holt, a food scientist at the University of Missouri in Columbia.
Different levels of irradiation are needed to kill different creatures. According to Karam, a lethal dose of irradiation for birds and mammals, including people, is about 500-2,000 rems (a unit measuring radiation). The lethal range for higher plants is in the 800 to 100,000 range. Viruses and bacteria (including anthrax) are killed only at a whopping dose of 8,000 to 1 million rems.
That means any irradiation used to treat bacteria such as anthrax is likely to kill most everything else. Karam points out the irradiation needed to kill anthrax is about a hundred million times stronger than what items are exposed to under an average airport security X-ray machine.
Postal workers operating the irradiation system will be safe from radiation exposure, according to Karam and William, since, unlike some irradiation systems that use radioactive elements to kill bacteria, electronic beam irradiation is completely contained and controlled.
But any living items inside the mail are a different matter.
That could prove to be a nuisance for some, but, besides keeping mail safe from anthrax, it could also provide some hidden benefits.
Holiday season is approaching and Karam says he'd feel much safer eating a fruitcake that's been irradiated — no matter how old it is.<<
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