As journalists of questionable caliber know, a good way to discover dirty secrets is to search through someone's trash. But now scientists are using a similar approach, by analyzing the sewage of 19 European cities to determine the drugs consumption level.
According to Fritz Sörgel, head of the Institute for Biomedical and Pharmaceutical Research in Nuremberg, Germany "The technique needs further work and validation, but this paper shows that it is a feasible approach for estimating drug use on a large scale."
Usually, to estimate the illicit of drug use, researchers use the survey results and data from the police. But these methods aren't accurate enough, so they had to find more precisely and objective method. One of the possibilities is to check the sewage of cities and look for chemical traces of drugs or doing drug tests with humans blood, saliva or hair.
In March 2011, Thomas, a toxicologist at the Norwegian Institute for Water Research in Oslo, and his colleagues collected samples of sewage flow from 19 Europe cities – from Antwerp to Zagreb. After analyzing the sewage, the results showed that there was evidence of the consumption of 5 different drugs.
Cannabis use is more or less the same throughout Europe. However there are differences in using other drugs. For example cocaine use is highest in Belgium and other parts of western and central Europe but lower in the north and east. As for the use of ecstasy, it's higher in Antwerp, London and cities in the Netherlands. While methamphetamine consumption is highest in the Scandinavian cities, in Budweis (Czech Republic).
In the study, published in Science of the Total Environment, researchers estimated that, on average, nearly 355 kg of cocaine were used in Europe every day during the study week. "But that number is just a rough estimate, since we extrapolated from cities to whole countries " says Thomas. A follow-up study currently being done, which includes in a city of the United States.
Sciencemag.org - 'Flushing out drug users'