Enantiomeric Profiling of Chiral Drugs in Wastewater and Receiving Waters

Chiral drugs, such as amphetamines, ephedrines, venlafaxine, and atenolol, break down differently depending on their mirror-image forms during wastewater treatment and in rivers. Monitoring at seven wastewater treatment plants (using activated sludge or trickling filters) and six river sites over nine months showed that the extent of this enantiomer-specific fate varied by drug, treatment method, and season. Atenolol and MDMA showed high stereoselectivity, activated sludge produced more stereoselectivity than trickling filters, and stereoselectivity in the environment was higher in spring and summer.

Study at a glance

Abstract

The aim of this paper is to discuss the enantiomer-specific fate of chiral drugs during wastewater treatment and in receiving waters. Several chiral drugs were studied: amphetamine-like drugs of abuse (amphetamine, methamphetamine, MDMA, MDA), ephedrines (ephedrine and pseudoephedrine), antidepressant venlafaxine, and beta-blocker atenolol. A monitoring program was undertaken in 7 WWTPs (utilizing mainly activated sludge and trickling filters technologies) and at 6 sampling points in receiving waters over the period of 9 months. The results revealed the enantiomer-specific fate of all studied drugs during both wastewater treatment and in the aqueous environment. The extent of stereoselectivity depended on several parameters including: type of chiral drug (high stereoselectivity was recorded for atenolol and MDMA), treatment technology used (activated sludge showed higher stereoselectivity than trickling filters), and season (higher stereoselectivity was observed in the aqueous environment over the spring/summer time).