Something kinky among the cans You're recycling bottles. Other people are dumping blow-up dolls.

`We've got the most unusual range of rubber clothing, whips and videos'

To you and me, they may appear solid and dependable. They're certainly environment-friendly. And some of them are even run by charities. For all their essential goodness, however, it seems that recycling banks are attracting an unfavourable reputation. Bank-emptying organisations, such as the Salvation Army and Scope, have found that, while most of us are content to fill the steel containers with our used clothes, newspapers and our empty bottles and cans, there are some who deposit more unusual goods:whips, for example, inflatable dolls, latex clothing and pornographic magazines and videos.

The explanation is simple. For while such sexual merchandise is easy enough to buy discreetly nowadays, disposal - when the material has become even dirtier than it was in the first place - is quite another matter.

"You can't take that sort of thing to the charity shop," says Lawrence M Barry, who runs a second-hand clothes export business based in east London and empties banks for Barnados and Scope. "And they don't want to put it in the dustbin, do they, because the dustmen will say `Aye Aye! We've got a kinky one living here!' "

To avoid embarrassment and to ensure completely discreet and anonymous disposal, most people, it seems, choose the recycling bank. "Anything unusual tends to be deposited in the textile banks," says Mr Barry. "We've got the most unusual range of rubber clothing, whips and dirty videos you could imagine."

All this would appear to be totally harmless. Unsaleable material in the textile banks is easily removed and consigned to landfill (or that's what they say), and while contamination of the bottle, paper and can banks does provide a considerable headache,processes for its removal are improving.

There is, however, a more serious side to the problem. Sexual fantasists are not alone in making use of the recycling banks' discreet disposal service. Murderers have deposited guns and knives in them, drug addicts use them to dispose of their old syringes; and bank robbers have found that textile banks are a good place for getting rid of dodgy clothing.

Such material is generally recovered immediately the banks are emptied. However, Garth Ward, National Co-ordinator for the Recycling Scheme at the Salvation Army, remembers one particular occasion when the police, searching for some robbers' clothing, alerted them too late.

"The bank had already been emptied," he says. "And the clothes had gone to join other clothes in a Parcelforce trailer. The police ended up doing a fingertip search through 10 tons of clothing, and they found nothing."

Most crime associated with the recycling banks is much more mundane. People deposit human faeces and, according to Mr Ward, bags of used condoms. Others use them to dispose of their deceased cats and dogs.

Down-and-outs have been found living in them - one was found in a textile bank with a candle alight in the corner. And it has become one of the mindless activities of the young to pour petrol inside and light it with a match. "This is the most serious problem we have," says Mr Barry. "About 7 per cent of all textile banks are burnt every year."

Another trend is that jilted partners and lovers have come to recognise the invaluable service offered by the banks. Wedding and engagement rings have been found in them. Paul Goodwin, administrative manager at Scope, reports that a man once approached them anxious to recover his best suit, which had been consigned to the bank by his ex-girlfriend. "We ended up searching through about 80 tons of material for it," he says, "and we still didn't find it."

People frequently put things into the banks by mistake. Some of this is easy enough to understand. People put Pyrex into the glass containers, for example - an easy mistake to make, but one that is sufficient to disrupt the whole recycling process.

Other errors, however, seem alarmingly absent-minded. Handbags, wallets and building society pass books have all been found in large numbers. All these can generally be recovered, but the emptying organisations all stress the need to inform them of the loss as soon as possible. "We had one woman who'd lost a pair of ear-rings," says Mr Ward. "lt was in October and she told us she'd lost them in April. We take in nearly 2 million items a month. You can imagine what chance we had of getting them back."