Cocaine, heroin and marijuana have become cheaper and stronger over the past two decades, despite increases in drug seizures by authorities fighting the global illegal drug market, a new study found.
The researchers looked at seven international drug surveillance databases to examine how the purity and price of illegal drugs changed between 1990 and 2009.
In the United States, the average purity of heroin, cocaine and marijuana increased by 60, 11, and 160 percent respectively, between 1990 and 2007, while the prices of these drugs, adjusted for inflation and purity, fell about 80 percent.
Data from Europe and Australia showed similar trends, with decreasing prices and increasing potency of drugs, according to the study published Monday (Sept. 30) in the journal BMJ.
The lower prices and higher purity of these drugs suggest that the illegal drug supply has increased during the past two decades. At the same time, patterns of drug seizures either increased or remained stable.
The findings suggest that "expanding efforts at controlling the global illegal drug market through law enforcement are failing," the researchers said.
