For the first time, scientists have made direct comparisons of illicit drug use in 19 European cities by a cooperative analysis of raw sewage samples. According to the researchers, the results could be used to inform the development of effective drug policies and also to measure the effectiveness of existing policies. The study, led by the Norwegian Institute for Water Research (NIVA) in Oslo and the Mario Negri Institute in Milan, appears in the journal Science of the Total Environment.
The detection of illicit drug usage by analyzing sewage has been trialed before, but the new study provides a complete picture of pan-European drug use. For the study, the researchers took samples from the inlets of 21 sewage treatment plants servicing a combined population of some 15 million people – about two percent of the region’s population.
Detection involved identifying the urinary biomarkers for cocaine, amphetamine, ecstasy, methamphetamine and cannabis. The total amount of the drugs used by inhabitants of each of the 19 cities was measured and then the results were adjusted for population size.
The results showed:
- In total, Europe uses about 350 kilograms of cocaine every day.
- Cocaine use was higher in Western and Central Europe and lower in Northern and Eastern Europe. Specifically, levels were highest in the Belgian port city of Antwerp followed by Amsterdam, Valencia, Eindhoven, Barcelona and London.
- Ecstasy levels were highest in Amsterdam and Utrecht, followed by Antwerp and London. No ecstasy was detected in Stockholm’s samples.
- Per capita loads of methamphetamine were highest in Helsinki, Turku, Oslo.
- Levels of cannabis use were similar throughout Europe.
- In general, cocaine and ecstasy loads were significantly elevated during the weekend compared to weekdays.
NIVA’s Kevin Thomas, who coordinated the project, believes that sewage analysis is far more accurate than traditional quantitative methods. “There will always be some uncertainty about the reliability of the results of questionnaire-based studies,” he said. “Our research approach based on sewer samples of European cities, however, yield very accurate and dependable results on the total amount of drugs used. Through sewer research, we can determine how big the drug market in a city is. We can also quickly measure changes in consumption over very short time, such as after a police raid or a customs seizure. We have the potential for the first time to better understand the hard facts about illicit drug use worldwide.”
Discuss this article in our forum
Study suggests the war on drugs might really be a war on sex
Drugs of addiction hijack our love of salt
Oxytocin has “blockbuster potential” as lifestyle drug
Sexsomnia linked to illicit drug use