Cocaine and ecstasy sold at 'unprecedented levels of purity'
Drugs including cocaine and ecstasy are being sold at unprecedented levels of purity in the UK, a new report warns.
Class A substances have seen sharp increases in strength as dealing gangs compete for customers, experts found.
The study also indicates that Spice - which mimics the effects of cannabis - has emerged as a street drug alongside heroin and crack after it was targeted by new laws on so-called "legal highs" last year.
Online information service DrugWise carried out a survey to build a snapshot of the street drug market in the UK.
It concluded that purity levels for heroin, crack, powder cocaine and ecstasy are unprecedented.
The report identified a two-tier market in cocaine with prices of around £30 to £40 a gram at "pub dust" purity of roughly 40% ranging up to approximately £80 for purity in excess of 70%. At the very top end of purity is cocaine known by the name "shine".
The report added: "There is a third tier in some metropolitan areas like London where people are paying anything up to £120 a gram, but this is more to do with dealers selling to people who have large disposable incomes (and want to show off about it) rather than anything to do with quality."
Possible factors mooted as being behind a rise in purity of heroin included that in one area users started "voting with their feet" in protest at the poor quality on offer.
It was also suggested that the increase could also be linked to the phenomenon known as "county lines" - where urban dealing gangs branch out into other areas.
The report also assessed the impact of the Psychoactive Substances Act, which came into force in May to outlaw legal highs - officially known as new psychoactive substances (NPS).
It said the legislation has largely achieved what it set out to do - which was to end the "blatant high street selling" of NPS.
However, the study also found that Spice - the name commonly used for synthetic cannabinoids - has joined the "street drug menu".
Harry Shapiro, director of DrugWise, said: "Spice as a street drug adds another layer of complexity and is a concern especially as the numbers of those rough sleeping continue to rise.
"But some of those interviewed thought that once former stocks of head shop spice sold onto the streets were exhausted, the bad reputation earned by Spice might see use diminish."
He added: "Other concerns are the strength of some street drugs which interviewees ascribed mainly to drug gangs competing for customers while fuelling the recent rise in drug-related deaths, and also the huge amount of opiate painkillers and tranquillisers in circulation both from legitimate medical and illicit sources.
"All of which underlines the need to retain investment in drug treatment and mental health capacity allowing the creation of new services to meet the challenges of an ever-changing drug market."
The report was based on interviews with drug treatment workers, police officers, researchers and other experts representing 32 organisations and 13 police forces.