VIENNA, June 22 (Xinhua) -- Global drug use remained relatively unchanged in 2015 with about 250 million users, the United Nations Office on Drugs and Crime (UNODC) revealed Thursday.
In its latest World Drug Report, the UNODC said of these users about 29.5 million were problematic users, meaning they had drug use disorders or dependence.
The most harmful category of drugs was opioids, accounting for 70 percent of the negative health impact associated with drugs.
Amphetamines were also responsible for significant harm, while new psychoactive substances (NPS) proved dangerous in that while their market is relatively small, users are often unaware of their exact contents or appropriate dosages, exposing them to risk.
The report also found that hepatitis C did the greatest harm among the approximate 12 million users who inject their drugs with 6.1 million sufferers, or over half the total. A further one in eight, about 1.6 million, had the HIV virus.
It was further noted that the business models for the drug trade are changing, with mobile communications providing new opportunities to traffickers, and the darknet allowing for the purchase of drugs anonymously through the use of crypto-currencies.
The darknet trade is still small at present, though studies indicate it has increased by about 50 percent a year since late 2013.