Paris - The global war on heroin, cocaine and cannabis is
failing to stem supply, as prices of these drugs have tumbled while seizures of
them have risen, according to a study published on Monday.
Researchers analysed data from seven government-funded
programmes that tracked the illegal drug market over more than a decade.
Three of the programmes monitored international drugs
trafficking; three focused on the United States; and one tracked the drugs
business in Australia.
The prices of heroin, cocaine and cannabis tumbled by 81%,
80% and 86% respectively between 1990 and 2007 in the United States when
adjusted for inflation, the researchers found.
Over the same period, the average purity of these drugs rose
by 60%, 11% and 161% respectively.
In 18 European countries, the street price of cocaine and
heroin fell by 51 and 74% between 2000 and 2009.
Neither the purity of drugs seized in Europe nor the price
of cannabis on the continent was given in the study.
In Australia, meanwhile, the inflation-adjusted price of
cocaine fell by 14% between 2000 and 2010, and that of heroin and cannabis by
Major domestic markets
"During this time, seizures of these drugs in major
domestic markets generally increased," said the study's authors, led by
Evan Wood of the Urban Health Research Initiative in Vancouver, Canada.
"With few exceptions... illegal drug prices have
generally decreased while drug purity has generally increased since 1990,"
The global supply of illicit drugs had likely not been
reduced in the last two decades, the study said, and the availability of
cannabis and opiates like heroin may even have increased.
"These findings suggest that expanding efforts at
controlling the global illegal drug market though law enforcement are
failing," said the paper published in the open-access journal BMJ Open.
The findings coincide with debate in several countries about
whether to loosen laws on certain drugs.
Uruguay in August took a step towards becoming the world's
first nation to produce and distribute marijuana after its lower house of
parliament approved a bill putting control of the drug in government hands.
In a 2011 report, the UN Office on Drugs and Crime (UNODC)
estimated the global illegal drug trade to be worth at least $350bn annually.