Cocaine is the most widely used illegal stimulant drug in Europe, according to the 2018 European Drug Report by the European Monitoring Center for Drugs and Drug Addiction (EMCDDA).

More than 92 million adults in EU member states, Norway and Turkey have tried an illicit drug, with around 1.6 million of those receiving treatment for drug use. The figures used in the report are from 2016.

The drugs agency says increased production in Latin American countries is being felt in Europe. Although prices have remained stable, the drugs' purity has improved, making it more dangerous.

"Early warnings from wastewater analysis about rising cocaine availability are now supported by other data suggesting growing supply, including increases in purity and in the number and quantity of cocaine seizures," Director Alexis Goosdeel said.

It said there was an increase of cocaine residue in the wastewater of 26 out of 31 European cities surveyed in the last three years. Cities in Belgium, the Netherlands, Spain and Britain showed the highest concentrations.

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The number of cocaine seizures has also risen, with around 98,000 incidents reported in the EU in 2016, compared with 90,000 in 2015.

Higher production in Europe

Drug production in Europe is also on the rise, according to the agency. It cites evidence of more illicit laboratories both for cocaine and synthetic drugs production being taken down.

Cannabis is still the most widely used illicit drug in Europe, with around 1 percent of European adults using it on an almost daily basis, the EMCDDA found.