Neuropsychiatric pharmaceuticals and illicit drugs in wastewater treatment plants: a review

Environmental context Neuropsychiatric pharmaceuticals and illicit drugs in wastewaters are of increasing environmental concern. We compile the recent literature and evaluate the concentrations and profiles of various drugs and their removal efficiencies in wastewater treatment plants. The sewage epidemiology approach, used in the estimation of drug usage in communities, is discussed, and we make recommendations for future research in this area. Abstract Neuropsychiatric pharmaceuticals and illicit drugs encompass a broad range of compounds including opioids, amphetamine-type stimulants, cannabinoids, benzodiazepines, barbiturates, antipsychotics, anaesthetics, anti-epileptics and mood stabilisers, lysergic compounds, sympathomimetic amines and cocaine derivatives. In this article, we review studies on the occurrence and fate of these drugs in wastewater treatment plants. In general, among various drugs studied, the concentrations and detection frequencies of opioids and cocaine derivatives were the highest in wastewaters. The forensic analysis of wastewaters suggests that cocaine and opioids usage has increased. Given the fact that data on drug usage can be used for making regulatory decisions and policies, this review focuses on understanding the sources and environmental dynamics of neuropsychiatric and illicit drugs. There is a pressing need for more research on the magnitude and extent of illicit drug consumption. The ‘sewage epidemiology’ approach, currently applied in the estimation of illicit drug consumption in communities, is reviewed. The field of wastewater research has been advancing in multipronged paths, incorporating concepts in analytical chemistry, organic chemistry, environmental chemistry, biochemistry, sewage engineering, drug epidemiology and statistics. Future prospects with regard to the occurrence and environmental fate of illicit and psychoactive drugs are recommended.