(Sources of Heroin Trafficked to European Union) "Heroin is the most common opioid on the European drug market. Imported heroin has historically been available in Europe in two forms: the more common is brown heroin (its chemical base form), originating mainly from Afghanistan. Far less common is white heroin (a salt form), which historically came from South-East Asia, but now may also be produced in Afghanistan or in neighbouring countries. Other opioids seized by law enforcement agencies in European countries in 2014 included opium and the medicines morphine, methadone, buprenorphine, tramadol and fentanyl. Some medicinal opioids may have been diverted from pharmaceutical supplies, while others are manufactured specifically for the illicit market.
"Afghanistan remains the world’s largest illicit producer of opium, and most heroin found in Europe is thought to be manufactured there or in neighbouring Iran or Pakistan. Opioid production in Europe has historically been limited to homemade poppy products produced in some eastern countries. However, the discovery of two laboratories converting morphine to heroin in Spain and one in the Czech Republic in 2013/14 indicates that heroin may also now be manufactured in Europe.
"Heroin enters Europe along four trafficking routes. The two most important are the ‘Balkan route’ and the ‘southern route’. The first of these runs through Turkey, into Balkan countries (Bulgaria, Romania or Greece) and on to central, southern and western Europe. An offshoot to the Balkan route involving Syria and Iraq has emerged recently. The southern route seems to have gained importance in recent years. This sees heroin shipments from Iran and Pakistan entering Europe by air or sea, either directly or transiting through west, southern and east African countries. Other, currently less important routes include the ‘northern route’ and a new heroin route that appears to be developing through the southern Caucasus and across the Black Sea."

Source

European Monitoring Centre for Drugs and Drug Addiction (2016), European Drug Report 2016: Trends and Developments, Publications Office of the European Union, Luxembourg, p. 22.
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