Drug abuse is at its lowest level for a decade following a sharp fall in numbers of people smoking cannabis.
About 3.2 million people in England and Wales aged between 16 and 59, equivalent to 10 per cent of the population, took an illicit substance in the past year. They included 2.6 million who used cannabis and 1.1 million who took class A drugs such as cocaine, heroin or ecstasy, according to new Home Office research.
Almost two million said they were regular drug users, having taken an illegal substance within the past month. The proportion of people who have smoked cannabis in the past 12 months is now 8.2 per cent, a significant fall from the 10.6 per cent from the research of five years ago and 8.7 per cent last year.
Its use is dropping even more quickly among young adults, with 20.9 per cent in the 16 to 24 age group using cannabis in the previous year, compared with 28 per cent in 1998.
The fall comes as the Government considers reversing the controversial downgrading of cannabis from a class B to a class C substance in 2004. Warnings have grown that stronger strains of the drug, such as "skunk", are circulating and that the mental health of heavy cannabis users could be jeopardised.
Martin Barnes, the chief executive of the charity DrugScope, said: "It is interesting and encouraging we've seen this downward trend in cannabis use. Given all the controversy over its reclassification, the fact that it has continued to fall has surprised some of the critics of the move.
"One of the results of the reclassification was a lot of debate about the harms cannabis can cause."
Use of class A drugs has remained largely unchanged since the start of the decade, after increases in the late 1990s largely caused by cocaine's growing popularity.
The British Crime Survey (BCS), which compiled figures for 2006-07, which it released yesterday, found slight increases in cocaine and ecstasy use, with falls in numbers of people taking LSD or magic mushrooms. The level of heroin abuse remained unchanged. However, the numbers taking amyl nitrites, known as "poppers", or sniffing glue rose since last year.
For the first time the survey asked about the use of the hallucinogen ketamine, nicknamed "special K" and mainly found on the club and rave scene. It found 0.3 per cent admitting taking it in the previous year, including 0.8 per cent of those in the 16-24 age group.
The BCS found the highest level of overall drug abuse in the South-west, with 11.1 per cent in the region saying they had taken an illegal substance in the past year. Levels of class A use were highest in the North-east (4.1 per cent) and North-west (4 per cent).
Other figures released by the Home Office disclosed that 161,100 drug seizures took place in 2005, up 50 per cent on the previous year. The increase was caused by a surge of cannabis seizures to 114,200, with 70 tonnes of herbal and resin cannabis and 208,000 plants confiscated. There were also 38,600 seizures of Class A drugs, up 31 per cent on the previous 12 months.
More than one-third of the population, about 11.3 million people, admitted using drugs at some point in their lives, including 4.4 million who have abused class A substances.
Vernon Coaker, a Home Office minister, said: "We are not complacent and know there is still a lot of work to do in tackling drug misuse, especially cocaine."