Determination of Pharmaceuticals Discharged in Wastewater from a Public Hospital Using LC-MS/MS Technique

Abstract

Abstract. The presence of pharmaceuticals classified as emerging contaminants (EC) in surface water, groundwater, and drinking water generates uncertainty concerning the interactions that could be occurred with aquatic organisms and living beings. Thus, the monitoring of hospital wastewater is of great importance to identify the main classes of pharmaceuticals that could be discharged to the municipal sewage system and wastewater treatment plants (WWTPs). This work described the implementation and validation of a highly selective and sensitive analytical method using solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the detection and quantification of these emerging compounds. The solid-phase extraction (SPE) method was employed using Oasis HLB cartridges. For LC-MS/MS analysis, the chromatographic separation was conducted in a C-18 Kinetex column (Phenomenex), and detection was achieved in an AB SCIEX QTrap 3200 tandem mass spectrometer (MS/MS) in the multiple reaction monitoring (MRM) mode. The quantitative analysis was performed by using the internal standard (IS) method with isotopically labeled analogs. The implemented method presented good linearity within the concentration range of 0.1–400 µg L-1 showing correlation coefficients (R2) ranged from 0.991 to 0.999. The limits of detection (LODs) were from 0.02 to 0.59 µg L-1, while the limits of quantification (LOQs) ranged from 0.07 to 1.80 µg L-1. The analytical method was successfully applied to the analysis of wastewater samples discharged by a public hospital in San Nicolas de los Garza, Nuevo Leon, Mexico, in two sampling periods: May 2017 and March 2018.
 
 Resumen. La presencia de fármacos, clasificados como contaminantes emergentes, en agua superficial, subterránea y potable, genera incertidumbre sobre las interacciones que podrían ocurrir con organismos acuáticos y los seres vivos. Por lo tanto, el monitoreo del agua residual hospitalaria es de gran importancia para identificar los principales productos farmacéuticos que podrían descargarse al sistema de alcantarillado municipal y por lo tanto, estar presentes en el agua a tratar en las plantas de tratamiento de agua residual (PTAR). Este trabajo describe la implementación y validación de un método analítico altamente selectivo y sensible utilizando extracción en fase sólida (SPE) y cromatografía líquida acoplada a espectrometría de masas tándem (LC-MS/MS) para la detección y cuantificación de estos compuestos emergentes. Se empleó el método de extracción en fase sólida utilizando cartuchos Oasis HLB. Para el análisis LC-MS/MS, la separación cromatográfica se realizó en una columna Kinetex C-18 (Phenomenex), y la detección se realizó en un espectrómetro de masas en tándem AB SCIEX QTrap 3200 (MS/MS) en el modo de monitoreo de reacciones múltiples (MRM). El análisis cuantitativo se llevó a cabo utilizando el método de estándar interno (IS) con análogos marcados isotópicamente. El método presentó una buena linealidad dentro del rango de concentración de 0.1 a 400 µg L-1, con coeficientes de correlación (R2) que oscilaron entre 0.991 y 0.999. Los límites de detección (LOD) fueron de 0.02 a 0.59 µg L-1, mientras que los límites de cuantificación (LOQ) variaron de 0.07 a 1.80 µg L-1. El método analítico se aplicó con éxito al análisis de muestras de agua residual vertidas por un hospital público de San Nicolás de los Garza, Nuevo León, México, en dos períodos de muestreo: mayo de 2017 y marzo de 2018.

Assessment of Trametes versicolor, Isochrysis galbana, and Purple Phototrophic Bacteria for the Removal of Pharmaceutical Compounds in Hospital Wastewater

“…The analytical method includes 79 PhACs of 19 various therapeutic groups (Table S1). The accuracy of the SPE method was assessed according to the recovery values obtained after spiking the samples with a standard mixture of the PhACs at 50 ngL -1 in triplicate [46]. Quantification was carried out based on the internal standard approach by the addition of the corresponding deuterated standards to all the samples and aqueous standards for preparing the calibration curve at a concentration of 0.01 ngL -1 [45].…”

Detection of Pharmaceutically Active Compounds in Tap Water Samples by Direct Injection HPLC/MS-MS: A Danger Signal in Deficiency in Residue Management

“…Traditionally, for the determination of pharmaceutical products in water samples has been implemented diverse techniques such as gas and liquid chromatography [5], which often require pretreatment sample steps for extraction and enrichment of target analytes, being the solid phase extraction more used [6][7][8]. However, solvent consumption, higher analysis time and costs, multiple human errors, and poor extraction of high-polar pharmaceutical compounds are disadvantages for the use of this sample pretreatment, and thus have been studied methods by the direct injection of samples for analysis through high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) [9,10].…”

Emerging pollutants and antibiotics removed by conventional activated sludge followed by ultraviolet radiation in a municipal wastewater treatment plant in Mexico

“…In Mexico, studies of EPs in aquatic environments are scarce (Félix-Cañedo et al 2013;Estrada-Arriaga et al 2016;Robledo-Zacarías et al 2017;Rivera-Jaimes et al 2018;Hernández-Tenorio 2021;López-Velázquez et al 2021). Besides, only 57% of WW generated and collected in municipal sewage systems receive some type of treatment before being discharged to water bodies CONAGUA (2016).…”