Scientists have found that London has the highest concentration of cocaine in its sewage system, closely followed by Amsterdam, according to test results from 50 European cities.
The EU’s drug monitoring body has determined that the average daily concentration of cocaine in London’s sewer system was 737mg per 1,000 people in 2014.
Measuring the concentration of drugs in waste water helps scientists monitor the level of illicit drug use in major metropolitan cities.
For instance, the amount of cocaine in London’s waste water drastically rises on Fridays and Sundays and falls back down on Sundays and Mondays, while in Amsterdam, consumption rises later in the weekend, peaking on Sunday.
Wastewater analysis is a “rapidly developing scientific discipline with the potential for monitoring real-time population-level trends in illicit drug use,” the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) said in its research.
The study also shows that Amsterdam’s sewers have much greater concentrations of cannabis, and London has the fourth highest daily concentration of ecstasy.
At the same time, drugs like cannabis, methamphetamine, and amphetamine were not found in London’s waste water.
Oslo in Norway and Dresden in Germany had the highest levels of methamphetamine in their sewage.
According to recent statistics, there were 2,995 drug related deaths in 2013 (involving both legal and illegal drugs), according to the UK Office of National Statistics’. This is up from 2012, when there were 2,597.