COMPACT DISC users beware: Your prized music or data could be
under attack. Scientists have discovered a fungus which, under the
right conditions, will literally eat compact discs and render the
information on them completely useless.
Victor Cardenes, a geologist at a leading Spanish research
institute, made the discovery on a trip to the Central American
country of Belize, where some friends showed him a CD which had a
strange discolouration that left it almost transparent, and
Intrigued, he took it back to Madrid, where he put the sample
under an electron microscope at the Superior Council for Scientific
Research. There, he found that a fungus had burrowed into the disc
from its outer edge, and eaten up the thin aluminium reflecting layer
and the polycarbonate resin that comprises the CD.
Information is stored on CDs by a pattern of “pits” in the
aluminium layer, which is held in the resin matrix. That is then
covered in a transparent lacquer. To read the disc, laser light is
shone onto the aluminium; the presence or absence of a pit is then
read as a digital 0 or 1. If the pits cannot be located, the CD is
“If you look at the CD from the shiny side, in the places where
the fungus has been you can see through to the other side,” Dr
Biologists at the council concluded that the fungus belonged to a
common genus called Geotrichum, but admitted they had never before
seen this particular species.
The cooler and drier weather in Madrid caused the fungus to stop
growing – suggesting that it thrives on tropical heat and humidity.
Hans Hofstraat, chief organic chemist at the electronics giant
Philips – which invented the CD in 1973 – said the case is “probably
a freak incident caused by extreme weather conditions” and insisted
the fungus poses no threat to the billions of discs used around the