Occurrence and behaviour of pharmaceutical compounds in a Portuguese wastewater treatment plant: Removal efficiency through conventional treatment processes

Abstract

Wastewater treatments can eliminate or remove a substantial amount of pharmaceutical active compounds (PhACs), but there may still be significant concentrations of them in effluents discharged into surface water bodies. Beirolas wastewater treatment plant (WWTP) is located in the Lisbon area and makes its effluent discharges into Tagus estuary (Portugal). The main objective of this study is to quantify a group of 32 PhACs in the different treatments used in this WWTP. Twelve sampling campaigns of wastewater belonging to the different treatments were made in 2013-2014 in order to study their removal efficiency. The wastewaters were analysed by solid phase extraction (SPE) and ultra-performance liquid chromatography coupled with tandem mass detection (UPLC-MS/MS). The anti-diabetics were the most frequently found in wastewater influent (WWI) and wastewater effluent (WWE) (208 and 1.7 μg/L, respectively), followed by analgesics/antipyretics (135 μg/L and < LOQ, respectively), psychostimulants (113 and 0.49 μg/L, respectively), non-steroidal anti-inflammatory drugs (33 and 2.6 μg/L, respectively), antibiotics (5.2 and 1.8 μg/L, respectively), antilipidemics (1.6 and 0.24 μg/L, respectively), anticonvulsants (1.5 and 0.63 μg/L, respectively) and beta blockers (1.3 and 0.51 μg/L, respectively). A snapshot of the ability of each treatment step to remove these target PhACs is provided, and it was found that global efficiency is strongly dependent on the efficiency of secondary treatment. Seasonal occurrence and removal efficiency was also monitored, and they did not show a significant seasonal trend.

Prevalence of Antibiotic Resistance Genes and Their Association with Antibiotics in a Wastewater Treatment Plant: Process Distribution and Analysis

“…Antibiotics are brought into the processing unit by effluent from the aerated sand settling tank and sludge from the secondary settling tank. The adsorption of activated sludge and the transformation and degradation of microorganisms play a key role in the removal of most antibiotics [7,44]. When compared with the previous treatment unit, the concentrations of TC, OTC, NOR, and ROX of aerobic and anaerobic sludge samples increased significantly, indicating that the TCs and QNs in the influent of the secondary settling tank were not actually removed, but shifted into the sludge.…”

Overview of Sample Preparation and Chromatographic Methods to Analysis Pharmaceutical Active Compounds in Waters Matrices

“…Wastewater samples should be previously filtered and, in some cases, centrifuged in order to remove suspended matter that may clog SPE sorbents [48].…”

“…The HLB sorbent is the SPE material that is most often ( Table 1) used in the extraction of PhACs belonging to different therapeutic classes [10,23,45,48,60,96].…”

“…Single quadrupole mass spectrometry [90,176,194], especially tandem mass spectrometry (MS/MS) with triple quadrupole detection [10,46,48,109,126,132,195], QTOF (quadrupole-time of flight) [173,196], and quadrupole-ion-trap [91,197], have been the most used techniques in recent years, due to their high sensitivity and selectivity.…”

“…Common mass analyzers applied in target analysis of these compounds are triple quadrupoles (QqQ) [45,46], ion-traps (IT) [38], and quadrupole-linear ion trap (QLIT-MS/MS) [37,47]. On the field of liquid chromatography coupled to tandem mass spectrometry, ultra-performance liquid chromatography (UPLC) has enabled the development of more sensitive, fast, and environmentally friendly methods for pharmaceuticals [10,[48][49][50].…”