Spatial differences and temporal changes in illicit drug use in Europe quantified by wastewater analysis

Abstract Aims: To perform wastewater analyses to assess spatial differences and temporal changes of illicit drug use in a large European population. Design: Analyses of raw wastewater over a 1-week period in 2012 and 2013. Setting and Participants: Catchment areas of wastewater treatment plants (WWTPs) across Europe, as follows: 2012: 25 WWTPs in 11 countries (23 cities, total population 11.50 million); 2013: 47 WWTPs in 21 countries (42 cities, total population 24.74 million). Measurements: Excretion products of five illicit drugs