Some 27 million people worldwide are problem drug users, with almost one percent every year dying from narcotics abuse, while cannabis remains the most popular drug, a UN report showed Tuesday.
"Heroin, cocaine and other drugs continue to kill around 200,000 people a year, shattering families and bringing misery to thousands of other people, insecurity and the spread of HIV," director Yury Fedotov said as he presented the 2012 World Drug Report of the UN Office on Drugs and Crime (UNODC).
Global production and use of illegal drugs remained relatively stable last year, the report found.
However, this masked shifts in trafficking and consumption that were "significant and also worrying... because they are proof of the resilience and adaptability of illicit drug suppliers and users," the UNODC warned.
Cannabis remained the most widely used drug with up to 224 million users worldwide, although production figures were hard to obtain, the agency said.
Europe was the biggest market for cannabis resin, most of it coming from Morocco, although Afghanistan is becoming a major supplier and domestic production in Europe is also rising, the UNODC said.
"Most European Union member states (are) reporting the cultivation of cannabis herb to be a phenomenon that appears to be on the increase," the report added, noting the increasing involvement of organised crime.
Opium production in Afghanistan, the world's biggest producer with 90 percent of the global share, meanwhile jumped by 61 percent in 2011 to 5,800 tonnes from 3,600 tonnes in 2010, when the crop was hit by disease.
In Southeast Asia as well, cultivating opium was increasingly popular, expanding by 16 percent in 2011, with Myanmar still the second largest producer behind Afghanistan.
Only a small share of this made it to Europe and North America, where opiate use was stable or dropping. Instead, 70 percent of users were in Africa and Asia, the report found.
Cocaine use too was stagnating or falling in Europe and North America, but this was offset by growing use in South America and Australia, as well as parts of Africa and Asia.
Synthetic drugs -- including methamphetamine and "ecstasy" pills -- were meanwhile on the increase, with a recent hike in seizures pointing to the drugs' continued popularity, the UNODC said.
Some 230 million people, or five percent of the global population aged 15-64, used illegal drugs at least once in 2010, the last year for which data was available, the report found.
As growth in use shifts increasingly from developed to developing countries, UNODC director Yuri Fedotov appealed for more help to newly-affected nations, ill-equipped to fight this problem.
Drug use has also been spilling more into countries along trafficking routes, such as Iran or parts of western and central Africa, the office noted.
Besides the health effects, the UNODC estimated the financial cost of drug use at about $200 billion to $250 billion (160 billion-200 billion euros) to cover drug treatment worldwide, a far cry from the sums currently provided.
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