Cocaine, MDMA and Amphetamine Capitals of Europe Ranked in New Report

Barcelona, Spain, has been crowned Europe's cocaine capital, according to a scientific study that tested the water in some of the biggest cities inside the European Union.

The survey was carried out by the SCORE group, which does Europe-wide wastewater analysis, in association with the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), the EU drugs agency. The survey sampled the wastewater of 56 cities across 19 different countries to test where illicit stimulant use is most concentrated. The researchers had access to wastewater plants treating the sewage coming out of each city, where they checked for the biomarkers of each drug and the metabolites that the body excretes in urine after the drug has been processed.

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Different drugs affect urine differently, and researchers were able to determine not only where illicit substances were used more but also which kind were the most popular. The agency tested for four different kinds of drugs and had some fascinating insights into Europe's top international clusters of drug use.

Methamphetamines, for example, are not widely popular, but in the neighborhoods of central Europe, specifically in the Czech Republic, Slovakia and eastern parts of Germany, traces feature strongly in the sewage. The top seven cities by methamphetamine use are all in those three countries alone, and Germany's Chemnitz leads the pack, with more than 240 milligrams for every thousand residents, according to the EMCDDA's press release.

Cocaine is much more popular throughout Europe, albeit more so in western and southern Europe than the rest of the continent. Barcelona, capital of the Catalonia region, goes through 965.2 milligrams a day per 1,000 residents, beating any other city surveyed. Swiss capital Zurich is in second place with 934.4 milligrams, and Belgium's Antwerp only slightly edges out another city in Switzerland, St. Gallen, with 822.9 milligrams to the latter's 821.7. The Alpine nation has four of its cities in the top 10 for cocaine use, more than any other.

Powdered cocaine is pictured in this undated handout photo, courtesy of the U.S. Drug Enforcement Administration. Barcelona, capital of Spain’s Catalonia region, goes through 965.2 milligrams a day per 1,000 residents, according to a new study. Reuters/US DEA/Reuters

The study came with some caveats, such as the exclusion of several large EU capitals like Madrid and London. The British city topped the table for cocaine use in 2014 and 2015, then finished second in 2016. The study also surveyed Eastern Europe much more sparsely, but researchers noted that the numbers still reveal "distinct geographical and temporal patterns of drug use in European cities."

By and large, MDMA is not very popular among Europeans, but in the Netherlands, Amsterdam is the runaway leader, with traces of the stuff in wastewater measuring 230.3 milligrams daily. For reference, Dutch city Eindhoven is the second of the nation's three entries in the MDMA top five, with 165.1 milligrams. Neighboring Antwerp is in third place with 95.3 milligrams a day.

The Low Countries also rank highly in the tests for amphetamine, where Eindhoven leads the pack with 271.7 milligrams a day and Antwerp is a close second with 268.8 milligrams. Overall, the Netherlands, Belgium and nearby Germany dominate the amphetamine map, as the top 17 consists entirely of cities from the three countries.