Illicit Drugs and Metabolites in the Llobregat River Basin

Abstract

Recently, the study of illicit drugs and metabolites in the aquatic environment has become a matter of scientific interest. An increasing number of studies have been carried out worldwide in this area of research in the last years. The Llobregat River basin has been one of the investigated areas in Spain. Its water quality has been shown to be affected by the presence of this type of emerging contaminants, often to a larger extent than other rivers, due to its marked Mediterranean character and urban and industrial pressures. This chapter reviews the occurrence of illicit drugs and their metabolites in both wastewaters and surface waters along the Llobregat River basin, and the analytical methodologies developed for their determination. Measured levels of these substances in the Llobregat River basin are compared with the levels found in other Spanish and European areas. Since treated wastewaters constitute the main source of illicit drugs and metabolites to the natural receiving waters, and surface waters are used for water supply purposes, the reported removal of these substances in wastewater treatment plants and drinking water treatment plants along the basin is also reviewed. Finally, the use of influent wastewater levels to estimate illicit drug use in riverine populations is also discussed.