Smelly toilets may soon be a thing of the past. Mitsubishi of Japan has
developed a high-energy plasma device for neutralising nasty odours. It claims
its Air Cleaner can purify 99.97 per cent of air passing through it at a rate of
four cubic metres a minute, banishing most common smells.
Moist air passes between a pair of high-voltage electrodes, which break it
down into a plasma of oxygen and hydroxide radicals. These radicals react with
molecules such as acetaldehyde, formaldehyde and volatile organic compounds from
cigarette smoke and excrement. The resulting odourless carbon dioxide and water
vapour pass through a carbon filter and are sent back into the room.