Dan Koster was unpacking some of his more than 2,000 CDs after a move when he noticed something strange. Some of the discs, which he always took good care of, wouldn't play properly.
Koster, a Web and graphic designer for Queens University of Charlotte, N.C., took one that was skipping pretty badly and held it up to the light.
Dan Koster, above, was shocked to discover pinholes in many of his older CDs. Mark Irons, left, displays the rotting fruit of technology. He says he still prefers CDs to vinyl.
(Nell Redmond -- AP)
"I was kind of shocked to see a constellation of pinpricks, little points where the light was coming through the aluminum layer," he says.
His collection was suffering from "CD rot," a gradual deterioration of the data-carrying layer. It's not known for sure how common the blight is, but it's just one of a number of reasons that optical discs, including DVDs, may be a lot less long-lived than first thought.
"We were all told that CDs were well-nigh indestructible when they were introduced in the mid-'80s," Koster says. "Companies used that in part to justify the higher price of CDs as well."
He went through his collection and found that 15 percent to 20 percent of the discs, most of which were produced in the '80s, were "rotted" to some extent.
The rotting can be due to poor manufacturing, according to Jerry Hartke, who runs Media Sciences Inc., a Marlborough, Mass., laboratory that tests CDs.
The aluminum layer that reflects the light of the player's laser is separated from the CD label by a thin layer of lacquer. If the manufacturer applied the lacquer improperly, air can penetrate to oxidize the aluminum, eating it up much like iron rusts in air.
But in Hartke's view, it's more common that discs are rendered unreadable by poor handling by the owner.
"If people treat these discs rather harshly, or stack them, or allow them to rub against each other, this very fragile protective layer can be disturbed, allowing the atmosphere to interact with that aluminum," he says.
Part of the problem is that most people believe it's the clear underside of the CD that is fragile, when in fact it's the side with the label. Scratches on the underside have to be fairly deep to cause skipping, while scratches on the top can easily penetrate to the aluminum layer. Even the pressure of a pen on the label side can dent the aluminum, rendering the CD unreadable.
Koster has taken to copying his CDs on his computer to extend the life of the recordings. Unfortunately, it's not easy to figure out how long those recordable CDs will work.
Fred Byers, an information technology specialist at the National Institute of Standards and Technology, has looked at writeable CDs on behalf of government agencies, including the Library of Congress, that need to know how long their discs will last.
Manufacturers cite life spans up to 100 years, but without a standardized test, it's very hard to evaluate their claims, Byers says. The worst part is that manufacturers frequently change the materials and manufacturing methods without notifying users.