Assessing illicit drugs in wastewater : advances in wastewater-based drug epidemiology

Monitoring illicit drug use is difficult because of the hidden and complex nature of drug-using behaviours. 'Wastewater analysis', or 'wastewater-based epidemiology', holds promise for complementing established methods of drug use measurement. Wastewater in municipal water treatment plants contains traces of chemicals that have been excreted and, most probably, consumed within the area served by a given sewer network. Detecting such residues in wastewater samples allows for non-invasive, near-real-time analysis of drug use. Wastewater analysis has some clear advantages over other approaches, as it is not subject to the biases associated with self-reported data and can better identify the true spectrum of drugs being consumed, which is particularly important as users are often unaware of the actual mix of substances they take. This tool also has the potential to provide timely information in short timeframes on geographical and temporal trends.