Simultaneous Determination of Seven Antibiotics and Five of Their Metabolites in Municipal Wastewater and Evaluation of Their Stability under Laboratory Conditions

Abstract

The selection and spread of antibiotic resistance poses risks to public health by reducing the therapeutic potential of antibiotics against human pathogens. Wastewater-based epidemiology (WBE) is potentially the most reliable approach to estimate antibiotics use. Previous WBE studies used parent antibiotics as biomarkers, which may lead to overestimation since parent antibiotics may be directly disposed of. Using metabolites as biomarkers can avoid this drawback. This study developed a simultaneous solid-phase extraction coupled with ultra-high-performance liquid chromatography tandem mass spectrometry method for analyzing 12 antibiotics and human metabolites in wastewater to help assess health risk. Optimum conditions were achieved using a PEP cartridge at pH 3.0. The extraction efficiencies were 73.3~95.4% in influent and 72.0~102.7% in effluent for most of the target analytes. Method detection limit ranged from 0.1 to 1.5 ng/L for influent wastewater and 0.03 to 0.7 ng/L for effluent wastewater. A stability experiment showed that sulfonamide parents and their metabolites were stable at 4 °C, −20 °C and −80 °C, while macrolides metabolites were more stable than their corresponding parents at 4 °C and −20 °C. Finally, the method was applied to measure these analytes in wastewater samples collected from three Beijing WWTPs and to derive apparent removal rates. All metabolites were detected in wastewater samples with concentrations ranging from 1.2 to 772.2 ng/L in influent, from <MDL to 235.6 ng/L in effluent. The apparent removal rates of five metabolites were above 72.6%. These results set a solid foundation for applying WBE to evaluate antibiotics use and its public health effects.

Inactivation of Bacteria and Residual Antimicrobials in Hospital Wastewater by Ozone Treatment

“…The problem of environmental pollution caused by the flow and persistence of antimicrobial-resistant bacteria and antimicrobials in rivers, lakes, and sea areas via wastewater systems has been reported worldwide [ 4 , 61 , 62 , 63 ], with reports pointing to the possibility of toxic effects on ecosystems [ 47 , 64 , 65 ]. Recent reports have suggested the possibility of the promotion of an unexpected emergence of antimicrobial-resistant bacteria from the environment [ 66 , 67 , 68 ].…”

Development and Validation of UPLC-MS/MS Method for Simultaneous Determination of Multi-Class Antibiotics, Antivirals and Antifungals in Water

“…Several LC-MS/MS analytical methods are available for the simultaneous estimation of multiple classes of antimicrobials, including β-lactams, cephalosporins, macrolides, sulfonamides, etc. in various water sources such as wastewater from hospitals, water treatment plants, surface and groundwater and environmental samples like soil [4,[21][22][23][24][25][26][27][28]. However, this work aims to develop a robust analytical method and validate the same to simultaneously detect antibiotics, antivirals and antifungals in water using tandem mass spectrometry.…”

Antimicrobial Resistance Development Pathways in Surface Waters and Public Health Implications

“…The metabolites are used as biomarkers to identify and estimate the concentrations of specific antibiotics in wastewater. A group of researchers detected the metabolites of macrolides (N-RTM and Des-ATM) and sulfonamides (N-SPY and N-SMX) in wastewater with their concentrations ranging from 1.2 to 772.2 ng/L [ 63 ], demonstrating the presence of antibiotic compounds in municipal wastewater. The release of antibiotic metabolites into wastewater is worsened by the rising self-medication practices across the world where up to 50% of over-the-counter medicines are antibiotics [ 64 , 65 ].…”