Disposition of Drugs of Abuse and Their Metabolites in Wastewater as a Method of the Estimation of Drug Consumption

The occurrence of drugs and trace amounts of their metabolites in the aqueous environment has become a global problem. Nowadays, general information about drug use patterns results from indirect methods such as anonymous surveys and police crime statistics. Unfortunately, these sources of information determine drug use consumption indirectly and give only rough estimations about drug use trends. Therefore, in order to assess the real extent of this phenomenon, new objective tools are needed to monitor drug abuse on a large social and international scale. Several analytical methods have been developed to diagnose illicit drug consumption. GC-MS and HPLC-MS are the techniques of choice for the quantitative analysis of illicit drugs and their metabolites in clinical and forensic toxicology. These separation methods have been widely used for the determination of the occurrence of stimulatory drugs in different biological matrixes such as blood, urine, sweat, saliva and hair. Recently, a new direct and objective approach of monitoring drug use patterns has been proposed to estimate illicit drug consumption involving the measurement of urinary breakdown products in waste- and surface water. The approach proposed seems to be suitable for monitoring consumption in real time so that it is possible to identify trends in drug use patterns. The measurement of illicit drug residue in wastewater and surface water might become a standardized tool for the comprehensive assessment of drug abuse in populations.