Do you have valuable VHS cassettes?

Perhaps you should check them. This report from the Guardian, courtesy of Nothing to do with Arbroath:

A virulent infection is destroying the audio and videotapes once used to capture important moments of family life and great historic events. The fungal blight, or 'tape mould', has already ruined thousands of miles of audio and video tape in Britain and, according to specialist restorers, much more is likely to be deteriorating, unobserved, in storage. The infection of VHS cassettes and of the audio cassettes popular in the 1980s and 1990s is increasing at an alarming rate.

'We used to get around one or two cases a year, and now about 10 per cent of all the work that is sent to us is mouldy. But sadly there is nothing we can do about it here,' said Chris Frear, who runs a restoration business in Scotland.

The wet summers of the last three years have taken the problem to epidemic proportions...

Video and audio tape is made from cellulose coated with ferric oxide, but, just like the sticky tape on an old parcel, it dries out and becomes brittle with age. Modern techniques can combat this ageing process, allowing the tapes to be digitally copied, but mould that has eaten into a tape is defeating conservationists. Typically tapes with the fatal fungus look as if they are covered with a fine white dust...