London is no longer Europe's 'cocaine capital' with Antwerp taking over

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Zaha Hadid AntwerpImage source, Reuters
Image caption,

Port House, a monumental design by Zaha Hadid Architects in Antwerp

For the past two years London has been the "cocaine capital" of Europe, but that title has now returned to the Belgian city of Antwerp, according to SCORE group, external.

Only Antwerp and London have been top of the list since the study began.

The research is carried out by analysing waste water, with samples of sewage taken in each area.

Amphetamine, methamphetamine and ecstasy were also studied but London didn't feature in the top 50 cities.

Image caption,

Bratislava in Slovakia is the methamphetamine capital of Europe

The report says that "the amphetamine loads in waste water in London was below the level of quantification".

Antwerp also tops the list for amphetamine and comes in second behind Eindhoven in the Netherlands for ecstasy.

London topped the list in 2014 and 2015

When looking at data for weekdays only, London remains on top.

In 2014 London measured 737.3mg per 1,000 people per day and 909.4mg in 2015.

But in 2016 the figures dropped to 894.9mg per 1,000 people per day as an average across the week.

This year is the closest Antwerp and London have been since the study began across 18 European countries.

The results are based on samples of sewage

A video by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) explains that measuring drug use is a difficult task because it "is a complex, hidden and often highly stigmatised behaviour".

The EMCDDA have shared a video to explain wastewater analysis., external

So they use something called wastewater analysis which takes samples in sewage treatment plants.

"Most of the chemicals which enter our body leave it unchanged or as mixture metabolites," the video explains.

"Drugs are no exception.

"When cocaine is used the body's metabolism breaks down its compound and [the] result, among other things, is benzoylecgonine.

"This ultimately ends up in the sewer network, most probably geographically close to where the cocaine has originally been used."

In most cities, wastewater MDMA loads were higher in 2016 than in 2011, with big increases seen in some locations.

That may be related to the increased purity of MDMA or increased availability and use of the drug, according to the EMCDDA.

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