The traditional cleaning cloth or wiping rag is a universal accessory in every kitchen, workshop and laboratory. But it is ecologically very unsound. The cloth either has to be cleaned in its turn, or must be thrown away, adding to the growing pile of organic waste. Seeking a better technology, Daedalus has been inspired by a kitchen household hint. To clean a dirty kitchen table, wipe it down with a kitten; then hand the kitten back to its mother for grooming.

This primitive biological ‘disposal at source’ can clearly be improved. DREADCO's biologists are devising a cleaning-rag bearing a carefully formulated mixed bacterial ecology. Some of the organisms degrade hydrocarbons, some hydrolyse proteins, and others split fats. The DREADCO ‘Dirt Eater’ will be made by dipping a thick inert fabric impregnated with polymerization catalyst into a bacterial culture containing suitable monomers. It will acquire a thin polymer coating loaded with trapped bacteria. A lightly crosslinked alkyd resin should resist bacterial attack while allowing water and organic molecules to diffuse readily through it. Bacteria are immortal, but trapped in the polymer they will have no room to divide. They will also be unable to escape to contaminate objects cleaned by the cloth. After each use, the Dirt Eater will slowly ‘digest’ the dirt it has picked up, turning it to gases or simple water-soluble molecules. A hygroscopic component in the cloth will prevent it drying out during its digestion period. An active kitchen or workshop would use a set of Dirt Eaters in rotation.

Dirt Eaters will rapidly replace traditional kitchen rags, domestic mops and bathroom flannels. They could even transform medical practice. A self-cleaning wound dressing would save the repeated work and distress of changing such dressings. For this service, however, even a small escape of bacteria could not be tolerated. Daedalus may have to devise a sterile Dirt Eater containing not trapped bacteria, but supported enzymes from them.

Yet even the most voracious bacterial or enzyme system will be unable to digest all possible contaminants. The Dirt Eater may also need a layer of that powerful photo-oxidation catalyst titanium dioxide. When it shows signs of indigestion, it could be laid out in the daylight for a while. Biologically resistant contamination would be mineralized, freeing the Dirt Eater for re-use.