The study of wastewater from 104 European cities in 21 countries — pending the publication of more complete data — has reflected the reality of drug use in the old continent. Spain is not doing well: Tarragona is the second European city in cocaine use, while Barcelona is the first in cocaine use and the third in cannabis.
This is reflected in a study by the European Observatory for Drugs and Drug Addiction (EMCDDA). The report, published this Wednesday and prepared by the European group Score in association with the Observatory -based in Lisbon-, shows that the six substances analyzed -cocaine, cannabis, amphetamine, methamphetamine, MDMA and ketamine- were present in "almost all the sites" in 2022.
It also adds that more and more traces of cocaine and methamphetamine are being detected in European wastewater and are spreading to new cities on the continent, revealing a "widespread" and "complex" drug problem, according to the EMCDDA.
As far as cocaine is concerned, the city analyzed with the highest daily consumption per 1,000 inhabitants is Antwerp, with a rate of about 2,400 milligrams of this drug on average per day. The second is Tarragona, with more than 1,600 milligrams.
Among the 15 cities that register the highest cocaine use according to the analysis of wastewater, there are five Spanish cities, apart from Tarragona: Lleida (760 mg/day for every 1,000 people), Valencia (724), Barcelona (622) and Castelló ( 554).
The traces of cocaine detected in wastewater have registered increases since 2016, although with "some fluctuation" during the confinement by the coronavirus.
They remained highest in western and southern European cities, especially in Belgium, the Netherlands, Spain and Portugal, but traces were also found in most eastern European cities, where there were increases.
More than half (38) of the 66 cities with data in 2021 and 2022 reported increases in cocaine residue, while 18 reported no change and 10 a decrease.
Barcelona is the city in which its wastewater contains the most ketamine. The study analyzes for the first time the presence of this drug and indicates that the highest loads of the drug occur in the wastewater of cities in Denmark, Italy, Spain and Portugal.
More than three-quarters of the cities studied reported higher ketamine loads in wastewater on the weekend (Friday through Monday) than on weekdays, reflecting the predominant use of ketamine in recreational settings, according to the study. study.
Specifically, in Barcelona the quantity of ketamine detected in milligrams per 1,000 inhabitants per day was 25.98 on weekdays and 32.06 on weekends, which represents a weekly daily average of 29.45.
These conclusions paint "a picture of a drug problem as widespread as it is complex", according to the director of the EMCDDA, Alexis Goosdeel, who considered that the wastewater samples can be an "early warning of emerging threats to health".
As far as cannabis is concerned, Barcelona —with an average daily consumption of more than 151mg per 1,000 inhabitants— is the third European city in this ranking. Ahead is Amsterdam (181 mg) and Geneva (170).
More methamphetamine residues were also detected, which were traditionally concentrated in the Czech Republic and Slovakia, but are now also present in Belgium, eastern Germany, Spain, Cyprus, Turkey and northern Europe (such as Denmark, Latvia, Lithuania, Finland and Norway).
Of the 60 cities with data in 2021 and 2022, almost two thirds (39) reported an increase in waste, 15 a decrease and six a stable situation.
As for the other four substances included in the study - amphetamine, cannabis, MDMA and ketamine - the picture is "mixed".
The highest loads of amphetamine were reported in cities in northern and eastern European countries (Belgium, Germany, the Netherlands, Finland and Sweden) and were much lower in the south, with increases or decreases depending on each city.
For MDMA, the highest residues were detected in cities in Belgium, the Czech Republic, the Netherlands, Spain and Portugal.
In general, there were increases in the majority of cities in southern and central Europe and a decrease in the north.
The highest concentrations of cannabis were recorded in western and southern cities, particularly in the Czech Republic, Spain, the Netherlands and Portugal, with "diverging trends" of increases or falls.
The study also detected "weekly patterns": more than three quarters of the cities showed higher residues of typically recreational drugs (cocaine, ketamine and MDMA) during the weekend, from Friday to Monday. The other three substances "were more evenly distributed."
The Score group has carried out annual wastewater monitoring campaigns since 2011 and since then 65 cities have participated in at least five, which has allowed analysis of temporal trends.
