Image caption Simple tests can quickly tell a real drug from a fake

Like it or not, drugs are a common feature of the UK festival scene, with over £100,000-worth seized in 2012 alone. But could a service that allows users to test the purity of their drugs before consumption help make them safer?

It is 10:30 on a Friday night in the outskirts of Bogota, Colombia and people are preparing for the biggest electronic music party of the year.

The three hanger-sized tents will soon be pulsing with thousands of ravers. But it is not just the music that will be giving people a rush.

That is why, tucked away in a corner, a group of people are installing an innovative addition to this Colombian club night: a drug testing laboratory.

It is currently the only place in the world where party-goers can walk a few steps from the dancefloor and get an instant analysis of what it is they are about to take.

"We can perform chemical tests that allow us to define two things: whether the substance is what the user thinks it is, and whether it contains a dangerous adulterant," explains Julian Molina, who works for the NGO Accion Tecnica Social.

"The idea is to have reliable information to help you make a better decision about whether or not to take the risk."

Testing debate

Established drug checking services already exist in Portugal, Spain, Belgium, Austria, Switzerland and the Netherlands, although unlike Colombia, none of them tests on-site in the club.

These services form part of the much larger Trans European Drug Information (TEDI) project, which released a report this week showing exactly what is in the most commonly used party drugs.

What's in your pill or powder? The Trans European Drug Information project assesses the changing trends in recreational drug use twice a year.

MDMA (ecstasy), cocaine and amphetamines are the most commonly used substances, with LSD and ketamine not far behind.

Drug purity varies widely from country to country. In Belgium, 55% of what users thought was crystal MDMA actually contained no MDMA whatsoever. In Austria, this happened in only 6% of cases.

Out of 709 samples of cocaine, 85% were cut with other substances.

Levamisole - used mostly to deworm livestock but also as part of certain human cancer treatments - is found in over a third of cocaine samples.

The painkiller phenacetine is found in 19% of cocaine samples. It can cause significant liver damage when used in combination with alcohol.

In amphetamine sulphate (speed) the main adulterant is caffeine.

While ecstasy is the least likely to be cut with other substances, it has also seen a 10% increase in the average dose in just six months.

This means that someone used to taking a few ecstasy tablets at a time might be getting a lot more than they bargained for.

In contrast, cocaine and amphetamines are being adulterated more and more, with the most regular cutting agents being caffeine, levamisole, phenacetine and local anaesthetics.

Even so, there are no drug checking services in the UK.

A Home Office spokesperson told the BBC: "The possession of controlled drugs is illegal, and we will not agree with any proposal which breaches our drugs laws."

But Roel Kerssemakers, a health education officer at the Dutch drug-checking service Jellinek, thinks that testing makes sense.

"For a long time there's been this policy not to use drugs. While it's useful in schools, that message doesn't make sense on the party circuit," he told the BBC.

"If people are going to do it, then we should try to get them to use drugs in a sensible way."

A bitter pill

Drug checking comes in two main forms.

How on-the-spot testing works There are a range of chemical tests that can help quickly determine whether a drug is what is purports to be.

Marquis' test is used to detect MDMA (the active ingredient in ecstasy) and amphetamines.

The chemical starts off clear and changes colour when it comes into contact with specific drugs.

MDMA will turn the liquid a dark purple-black, while amphetamines will make it orange-brown.

In Colombia, they are using a modified version of something known as a "Scott test" to roughly calculate the amount of cocaine in a sample.

On-the-spot testing only works for the most commonly used drugs and even then, results will only be approximate.

There are no rapid tests for new drugs. These can only be analysed by fully-equipped labs.

The first is a "while-you-wait" service where people can take along a pill or powder and have it analysed on the spot.

The tests involve quick colour-change chemical reactions that can detect the presence of MDMA, amphetamines or cocaine.

Chemical tests can also help to roughly measure the purity of cocaine and identify common adulterants.

In the Netherlands, pills can also be compared against a database of pre-tested drugs already known to be on the market.

If the drug cannot be identified, then the second step is to send it to a proper lab for analysis.

Where drug checking services exist, recreational users will often send samples to the lab a week or two in advance to make sure the results are back in time for the next big night out.

Although it might seem like a lot of hassle, it helps to weed out the poor quality and dangerously adulterated drugs before they hit the dancefloor.

High and dry?

Back at the rave in Bogota, it is past midnight and the drug lab is still hard at work.

Image caption About 3,000 people attended this year's Radikal Styles event in Bogota, Colombia

A 19-year-old girl arrives with samples of the drugs she has been taking - so far a mix of alcohol, cocaine and what she believes to be LSD and ecstasy.

With extremely dilated pupils, she high-fives her friend as she is told the ecstasy is real.

However the cocaine is only between 25% and 50% pure.

And although they do not currently have a test for LSD, knowledge of the current market suggests it is unlikely to be LSD.

"Most of what's selling as LSD in Bogota right now really isn't," says Julian Molina, who runs the lab. "Consumers have no idea what it is."

But while drug checking has its undoubted benefits for those who want to reduce their risk, the while-you-wait testing in clubs also has its downsides.

"We also used to test in clubs [here in the Netherlands] but the problem is that there were so many drugs we couldn't recognise," says Jellinek's Roel Kerssemakers.

The difficulties are caused by a huge explosion of "new" drugs and legal highs, which are being developed in labs and sold over the internet.

A recent report the European Monitoring Centre for Drugs and Drug Addiction revealed that 73 new drugs were identified in 2012 alone.

At this weekend's Glastonbury Festival, police will be testing seized drugs in an on-site lab to help them keep across the latest trends.

But Kerssemakers thinks that by encouraging people to test, it makes it even easier to spot the kinds of drugs that are circulating.

"With the Dutch system, we can find dangerous pills much earlier and send a red alert out to the community much more quickly," he told the BBC.

He is also keen to point out that even with a "good" result, they never tell people that their drugs are safe.

"We always say that taking drugs is taking a risk."