COCAINE traces have been found in 12 out of 15 pubs tested in Purley, Coulsdon, Selsdon and Kenley.

An investigation conducted by the Advertiser, in which we tested each pub's toilets, suggests women are almost as keen on the drug as men, with 10 of the 12 pubs having traces in the female as well as male loos.

All landlords stressed their "zero tolerance" after being contacted by the Advertiser, but many said it was almost impossible to stamp out the drug's use.

Bryan Davy, landlord of Pistols in Coulsdon, said: "It's a big problem, a major, major problem.

"But the situation is that, as with anybody who goes into any toilet in any place, we don't know what they have in their pockets.

"I know there has been cocaine use in my pub, I have been a publican for a number of years and it doesn't surprise me.

"It's as popular with the under-40s now as smoking. It's a sad state of affairs."

Mr Davy, 63, added: "The police's allocation of funds is being cut so if they haven't got a sufficient labour force to carry out checks and sort the situation it can only get worse.

"We never really see police in Coulsdon, they are more needed in Croydon, but I suppose they are doing what they can with the resources available.

"But if I find anyone carrying or supplying it not only will I ban them I will report them to the local authorities.

"We do everything in our power to stop it."

Ian Harris, landlord of the Jolly Farmers in Purley, said: "The number of people who take it these days is very high. It is a social habit now – in certain groups it is socially acceptable.

"In this trade unfortunately it happens. But people who use these drugs, when we find them, are banned for life and we have no tolerance of it whatsoever.

"With the bands we bring in there are new people coming into our pub all the time but whenever we find people using it they are banned straight away."

Landlords use techniques such as spraying WD40 and olive oil around toilets to break up cocaine when laid on surfaces. They also carry out regular toilet checks.

Anne Bonass, the landlord of Elliott's in Purley, said: "I really wish we could stop them doing it. It is not welcome and a real problem."

The Advertiser wiped 15 pubs' toilet cisterns, toilet roll holders and seats, window shelves and floors with cocaine-testing equipment used by the Metropolitan Police.

A presence of the drug turns swabs blue as they are saturated with cobalt thiocyanate – a compound causing a chemical reaction. Only traces of cocaine greater than 0.5 milligrams are detected.

We tested 11 pubs on a Saturday night two weeks ago (January 7) and four on the following Sunday afternoon.

All pubs said they cleaned their toilets on a regular basis, meaning the use of cocaine would have been recent, according to former Croydon Police licensing officer Chris Gould.

Mr Gould, now director of Premier Licensing Consultants, added: "I think it is good that the Advertiser is doing this because it highlights how widespread the problem is.

"In my opinion drug usage in licensed premises has been a problem for a number of years and does not appear to be getting any better."

Inspector Alan Goodall, of the Croydon licensing unit, said: "Licensed venues in Croydon have an obligation to support the prevention of crime and disorder and ensure that drugs are not being used or sold on their premises as part of the terms of their licence.

"Our licensing unit carries out random visits to venues across Croydon to test whether or not there are any traces of drugs.

"Any venues that show up positive traces are then spoken to by the licensing unit – reminding them of their obligations to prevent crime and disorder and giving them advice on how they can stop this from recurring."