Presence Of Pharmaceutical Compounds Research Articles

Degradation of X-Ray Contrast Media in Anaerobic Membrane Bioreactors

The presence of pharmaceutical compounds, including iodinated contrast media (ICM), in aquatic systems poses significant ecological and health risks due to their biological activity at low concentrations. This study investigated the removal efficiency of three selected ICM—diatrizoate, iohexol, and iodipamide—from synthetic hospital wastewater using anaerobic membrane bioreactors (MBRs) operated at varying sludge ages of 40, 70, and 100 days. The results indicated that the performance of the MBRs in removing organic compounds improved with increased sludge age. Diatrizoate exhibited the highest removal efficiency, achieving 72% at a sludge age of 40 days and nearly 90% at 70 and 100 days, with no substantial differences between the two higher sludge ages. In contrast, iohexol and iodipamide demonstrated relatively low and inconsistent removal efficiencies, reaching a maximum of 40%, with no observable dependency on sludge age. The findings underscore the importance of optimizing sludge age in biological treatment processes for effective ICM removal.

Enhancing photocatalytic tetracycline degradation through the fabrication of high surface area CeO2 from a cerium-organic framework.

Water pollution is a global environmental issue, and the presence of pharmaceutical compounds, such as tetracyclines (TCs), in aquatic ecosystems has raised growing concerns due to the potential risks to both the environment and human health. A high surface area CeO2 was prepared via atmospheric thermal treatment of a metal-organic framework of cerium and benzene-1,3,5-tricarboxylate. The effects of calcination temperature on the morphology, structure, light absorption properties and tetracycline removal efficiency were studied. The best activity of the photocatalysts could be achieved when the heat treatment temperature is 300 °C, which enhances the photocatalytic degradation performance towards tetracycline under visible light. The resulting CeO2 particles have high capacity for adsorbing TCs from aqueous solution: 90 mg g-1 for 60 mg L-1 TCs. As a result, 98% of the initial TC can be removed under simulated sunlight irradiation. The cooperation of moderate defect concentration and disordered structure showed tetracycline removal activity about 10 times higher than the initial Ce-MOF. An embryotoxicity assessment on zebrafish revealed that treatment with CeO2 particles significantly decreased the toxicity of TC solutions.

Analysis of chlorhexidine, antibiotics and bacterial community composition in water environments from Brazil, Cameroon and Madagascar during the COVID-19 pandemic

The widespread of chlorhexidine and antibiotics in the water bodies, which grew during the global COVID-19 pandemic, can increase the dispersion of antibiotic resistance. We assessed the occurrence of these pharmaceutical compounds as well as SARS-CoV-2 and analysed the bacterial community structure of hospital and urban wastewaters from Brazil, Cameroon, and Madagascar. Water and wastewater samples (n = 59) were collected between January–June 2022. Chlorhexidine, azithromycin, levofloxacin, ceftriaxone, gentamicin and meropenem were screened by Ultra-High-Performance Liquid Chromatography coupled with mass spectrometer. SARS-CoV-2 was detected based on the nucleocapsid gene (in Cameroon and Madagascar), and envelope and spike protein-encoding genes (in Brazil). The total community-DNA was extracted and used for bacterial community analysis based on the 16S rRNA gene. To unravel likely interaction between pharmaceutical compounds and/or SARS-CoV-2 with the water bacterial community, multivariate statistics were performed. Chlorhexidine was found in hospital wastewater effluent from Brazil with a maximum concentration value of 89.28 μg/L. Additionally, antibiotic residues such as azithromycin and levofloxacin were also present at concentrations between 0.32–7.37 μg/L and 0.11–118.91 μg/L, respectively. In Cameroon, azithromycin was the most found antibiotic present at concentrations from 1.14 to 1.21 μg/L. In Madagascar instead, ceftriaxone (0.68–11.53 μg/L) and levofloxacin (0.15–0.30 μg/L) were commonly found. The bacterial phyla statistically significant different (P < 0,05) among participating countries were Proteobacteria, Patescibacteria and Dependentiae which were mainly abundant in waters sampled in Africa and, other phyla such as Firmicutes, Campylobacterota and Fusobacteriota were more abundant in Brazil. The phylum Caldisericota was only found in raw hospital wastewater samples from Madagascar. The canonical correspondence analysis results suggest significant correlation of azithromycin, meropenem and levofloxacin with bacteria families such as Enterococcaceae, Flavobacteriaceae, Deinococcaceae, Thermacetogeniaceae and Desulfomonilaceae, Spirochaetaceae, Methanosaetaceae, Synergistaceae, respectively. Water samples were also positive for SARS-CoV-2 with the lowest number of hospitalized COVID-19 patients in Madagascar (n = 7) and Brazil (n = 30). Our work provides new data about the bacterial community profile and the presence of pharmaceutical compounds in the hospital effluents from Brazil, Cameroon, and Madagascar, whose limited information is available. These compounds can exacerbate the spreading of antibiotic resistance and therefore pose a risk to public health.

The presence of pharmaceutical compounds in Surabaya rivers: potential sources and correlation with other water quality parameters

Recently identified compounds and chemicals that are harmful to the environment and pose a major risk to human health, known as emerging pollutants (EPs), are receiving increasing attention today. The main basis for this study is the absence of studies that discuss the presence of anti-inflammatory and anti-pain medicines in river water in Surabaya. Based on the study results, it was found that the overall average paracetamol concentration was 333 μg/L in Mas River and 430 μg/L in Surabaya River. Meanwhile, the ibuprofen concentration was not detected at all sampling points. This can be caused by the levels of ibuprofen, which are very small or below the detection limit. River water quality standards are regulated in Appendix VI of Government Regulation of the Republic of Indonesia Number 22 of 2021. On average, other water parameters that were also monitored, namely BOD, COD, nitrate, and phosphate, exceed the class II quality standards. Meanwhile, the pH and temperature parameters are within the class II quality standards range. Further research is needed to determine the presence of EPs in Surabaya rivers. This research can be a useful reference for further research.

Mechanisms and factors affecting the removal of minocycline from aqueous solutions using graphene-modified resorcinol formaldehyde aerogels

In recent years, concerns about the presence of pharmaceutical compounds in wastewater have increased. Various types of residues of tetracycline family antibiotic compounds, which are widely used, are found in environmental waters in relatively low and persistent concentrations, adversely affecting human health and the environment. In this study, a resorcinol formaldehyde (RF) aerogel was prepared using the sol–gel method at resorcinol/catalyst ratio of 400 and resorcinol/water ratio of 2 and drying at ambient pressure for removing antibiotics like minocycline. Next, RF aerogel was modified with graphene and to increase the specific surface area and porosity of the modified sample and to form the graphene plates without compromising the interconnected porous three-dimensional structure of the aerogel. Also, the pores were designed according to the size of the minocycline particles on the meso- and macro-scale, which bestowed the modified sample the ability to remove a significant amount of the minocycline antibiotic from the aqueous solution. The removal percentage of the antibiotic obtained by UV–vis spectroscopy. Ultimately, the performance of prepared aerogels was investigated under various conditions, including adsorbent doses (4–10 mg), solution pHs (2–12), contact times of the adsorbent with the adsorbate (3–24 h), and initial concentration of antibiotic (40–100 mg/l). The results from the BET test demonstrated that the surface area of the resorcinol formaldehyde aerogel sample, which included 1 wt% graphene (RF-G1), exhibited an augmentation in comparison to the surface area of the pure aerogel. Additionally, it was noted that the removal percentage of minocycline antibiotic for both the unmodified and altered samples was 71.6% and 92.1% at the optimal pH values of 4 and 6, respectively. The adsorption capacity of pure and modified aerogel for the minocycline antibiotic was 358 and 460.5 mg/g, respectively. The adsorption data for the modified aerogel was studied by the pseudo-second-order model and the results obtained from the samples for antibiotic adsorption with this model revealed a favorable fit, which indicated that the chemical adsorption in the rapid adsorption of the antibiotic by the modified aerogel had occurred.

Sustainable development and analysis of a novel bio-derived (biochar) nanocomposite for the remediation of carbamazepine from aqueous solution

The presence of pharmaceutical compounds in aqueous environments has become a growing concern due to their potential adverse effects on ecosystems and human health. In this work, synthesis of a novel bio based nanocomposite using a biowaste, palm seed is employed for the preparation of biochar. The bio derived nanocomposite consist of polypyrrole (Ppy), graphene oxide (GO), and biochar, is employed for the Carbamazepine (CBZ) removal. The synthesized nanocomposite, Ppy-GO-Biochar, is characterized using various analytical techniques. The characterization results confirmed the successful synthesis of the Ppy-GO-Biochar nanocomposite with the desired morphology and structural properties. The effect of variables is investigated and the optimum conditions are found as: pH (7.8), adsorbent dosage (1.4 g/L), agitation speed (200 rpm) and temperature (39.5 °C). The results demonstrated that a removal efficiency of over 97.74% and uptake of 45.045 mg/g is achieved for CBZ. Furthermore, the CBZ removal followed pseudo-second-order, indicating chemisorption as the predominant mechanism. The CBZ sorption equilibrium is well represented by Langmuir and Freundlich isotherm. Thermodynamic results show that CBZ sorption is endothermic and spontaneous. Mechanism of CBZ sorption using the synthesized nanocomposite follows π-π interaction and electrostatic attraction. Molecular docking studies were also performed for the sorption of CBZ.

Statistical modeling and optimization of dexamethasone adsorption from aqueous solution by Fe3O4@NH2-MIL88B nanorods: Isotherm, Kinetics, and Thermodynamic

The presence of pharmaceutical compounds in the environment poses a significant threat to human and aquatic animal health. Dexamethasone (DEX), a synthetic steroid hormone with endocrine-disrupting effects, is one such compound that needs to be effectively removed before discharging into the environment. This research presents a novel approach utilizing magnetically recyclable Fe3O4@NH2-MIL88B NRs as an efficient adsorbent for the treatment of DEX from aqueous solutions. The synthesized adsorbent was characterized by X-ray diffraction (XRD), scanning microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), diffuse reflectance spectra (DRS), and Fourier transform infrared spectroscopy (FTIR). Response surface methodology based on central composite design (RSM-CCD) was employed to optimize DEX removal efficiency by determining the optimal conditions, including pH, adsorbent dose, time, and DEX concentration. Under the optimized conditions (pH: 5.53, adsorbent dose: 0.185 g/L, time: 16.068 min, and DEX concentration: 33.491 mg/L), Fe3O4@NH2-MIL88B NRs revealed remarkable DEX adsorption efficiency of 91 ± 1.34% and adsorption capacity of 180.01 mg/g. The Langmuir isotherm and pseudo-second-order kinetic model were found to fit well with the experimental data, indicating a monolayer and chemical adsorption process. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. The study also investigated the inhibitory effect of background ions on DEX removal by Fe3O4@NH2-MIL88B NRs. Magnesium exhibited superior competitive ability with dexamethasone to occupy the active sites of the adsorbent compared to other background ions. The reuse of the adsorbent over ten consecutive cycles resulted in a 39.46% decrease in removal efficiency. The Fe3O4@NH2-MIL88B NRs are surrounded by abundant amounts of functional groups and π-electrons bands that can play a key role in the adsorption and separation of DEX from aqueous environments. The promising results obtained under real conditions highlight the potential of Fe3O4@NH2-MIL88B NRs as a practical and efficient adsorbent for the removal of DEX and other similar corticosteroids from aqueous solutions.

Impacts of Organic Emerging Contaminants (Erythromycin, Ibuprofen, and Diclofenac) on the Performance of a Membrane Bioreactor Treating Urban Wastewater: A Heterotrophic Kinetic Investigation.

The occurrence of emerging organic contaminants, such as pharmaceuticals, is a growing global concern. In this research, for a membrane bioreactor (MBR) laboratory plant operating at a hydraulic retention time (HRT) of 24 h, fed with real urban wastewater, the heterotrophic biomass behaviour was analysed for two concentrations of erythromycin, ibuprofen, and diclofenac. The concentrations studied for the first phase were erythromycin 0.576 mg L-1, ibuprofen 0.056 mg L-1, and diclofenac 0.948 mg L-1. For Phase 2, the concentrations were increased to erythromycin 1.440 mg L-1, ibuprofen 0.140 mg L-1, and diclofenac 2.370 mg L-1. Heterotrophic biomass was affected and inhibited by the presence of pharmaceutical compounds in both phases. The system response to low concentrations of pharmaceutical compounds occurred in the initial phase of plant doping. Under these operating conditions, there was a gradual decrease in the concentration of mixed liquor suspended solids and the removal of chemical oxygen demand of the system, as it was not able to absorb the effect produced by the pharmaceutical compounds added in both phases.

Recent advances in new generation nanocomposite materials for adsorption of pharmaceuticals from aqueous environment.

With rapid increase in the human population, a large amount of wastewater is generated every year. The availability of fresh water is decreasing at an alarming rate due to rapid industrialization and agricultural development. Pharmaceutical drugs which are credited for improving standards of life worldwide have emerged as major water contaminants, raising global concern about their potential risk to human health and environment. The presence of pharmaceutical compounds is detected in surface water (sea, river, lakes, etc.), groundwater, effluents from municipal, hospitals, and wastewater treatment plants, and even in drinking water. Efficient removal of pharmaceutical pollutants still remains a challenging task. Many techniques, including photodegradation, photocatalysis, oxidation, reverse osmosis, biodegradation, nanofiltration, adsorption, etc., have been used for the remediation of wastewater. Adsorption of pharmaceutical compounds on nanoadsorbents, as a low-cost and feasible technology, has gained immense popularity for wastewater treatment over the last decade. Adsorption techniques can be integrated with wastewater treatment plants to achieve efficient removal on an industrial level. Herein, we review the literature on the remediation techniques used for the pharmaceutical waste treatment using carbon nanotubes, metal oxides, nanoclay, and new-generation MXenes via adsorption. These materials show excellent adsorptive properties owing to their high surface area, low cost, high porosity, easy functionalization, and high surface reactivity. The adsorption mechanism of the nanoadsorbents and their reusability as a factor of sustainability have also been included in the review. The factors affecting the adsorption, including pH, the concentration of adsorbate, ionic strength, and adsorbate dose, have also been discussed.

Microalgae, a current option for the bioremediation of pharmaceuticals: a review.

In this review, research on the use of microalgae as an option for bioremediation purposes of pharmaceutical compounds is reported and discussed thoroughly. Pharmaceuticals have been detected in water bodies around the world, attracting attention towards the increasing potential risks to humans and aquatic biota. Unfortunately, pharmaceuticals have no regulatory standards for safe disposal in many countries. Despite the advances in new analytical techniques, the current wastewater treatment facilities in many countries are ineffective to remove the whole presence of pharmaceutical compounds and their metabolites. Though new methods are substantially effective, removal rates of drugs from wastewater make the cost-effectiveness ratio a not viable option. Therefore, the necessity for investigating and developing more adequate removal treatments with a higher efficiency rate and at a lower cost is mandatory. The present review highlights the algae-based removal strategies for bioremediation purposes, considering their pathway as well as the removal rate and efficiency of the microalgae species used in assays. We have critically reviewed both application of living and non-living microalgae biomass for bioremediation purposes considering the most commonly used microalgae species. In addition, the use of modified and immobilized microalgae biomass for the removal of pharmaceutical compounds from water was discussed. Furthermore, research considering various microalgal species and their potential use to detoxify organic and inorganic toxic compounds were well evaluated in the review. Further research is required to exploit the potential use of microalgae species as an option for the bioremediation of pharmaceuticals in water.

Agro-industrial residues as biosorbents for the removal of anti-inflammatories from aqueous matrices: An overview

• First review of biosorbents for pharmaceutical removal; • Focusing on the anti-inflammatory class of pharmaceutical compounds; • Overview considering residue processing and its performance; • Evaluation of adsorption parameters for NSAID removal. The presence of pharmaceutical compounds (PCs) in waters has concerned the scientific community because of their occurrence, persistence, and potentially deleterious effects on human health and aquatic ecosystems. Consequently, studies on the removal of PCs have intensified in the last decade. Because of the lack of deep analysis of this subject, the present study aimed to review the main methods for nonsteroidal anti-inflammatory drug (NSAID) removal from aqueous matrices using biosorbents. The study focused on the adsorption process using adsorbents derived from agro-industrial residues: raw materials, activated materials, biochar, and activated carbon. For this purpose, an overview of publications between 2011 and 2021 was performed on the scientific databases. The consulted literature focused on NSAIDs of highest incidence in water matrices (acetaminophen, ketoprofen, diclofenac, ibuprofen, naproxen, and paracetamol). The evaluated articles report several procedures for preparing and modifying adsorbent materials, in addition to studies concerning the equilibrium, kinetics, and thermodynamics of the adsorption process. Agro-industrial residues converted into activated carbon were the most reported and had improved performance compared to less-processed biosorbents. The use of adsorbents derived from agro-industrial residues is a promising strategy for NSAID removal from water and wastewater. However, further investigations are necessary to provide reliable parameters aimed at upscaling water treatment on a large scale.

Catalytic ozonation process using ZnO/Fe2O3 nanocomposite for efficient removal of captopril from aqueous solution

The presence of pharmaceutical compounds in aqueous media, even in low concentrations, has caused adverse effects on human, animal, and environmental health. Captopril is a widely used pharmaceutical compound detected in the environment at different concentrations. Because of the concern and problems caused by the presence of captopril in water and the aquatic ecosystem, it appears necessary to remove it from the environment. The current study investigated captopril removal by a catalytic ozonation process using ZnO/Fe2O3 nanocomposite as a low-cost catalyst. The effects of variables such as ZnO/Fe2O3 nanocomposite dosage (0.5-2.5 g L-1), solution pH (3-11), initial captopril concentration (10-70 mg L-1), and ozone dosage (0.2-1.5 mg min-1) on captopril removal were investigated. The removal captopril of 99.4% was obtained in the optimum condition, including ZnO/Fe2O3 nanocomposite dosage of 2.0 g L-1, solution pH of 5.0, initial captopril concentration of 40 mg L-1, and ozone dosage of 0.5 mg min-1. The ZnO/Fe2O3 nanocomposite as a catalyst was a critical component in the catalytic ozonation process. According to the obtained results, the catalytic ozonation process in the presence of ZnO/Fe2O3 nanocomposite has high efficiency in removing captopril from water sources.

The effects of caffeine, gliclazide, and prazosin on the performance and microbial diversity in an up-flow anaerobic sludge blanket (UASB) reactor

A laboratory-scale up-flow anaerobic sludge blanket (UASB) reactor was deployed in this study to examine the relationship between pharmaceutical compounds and anaerobic process performance. The reactor successfully biotransformed up to 87–99% of psychostimulant caffeine, anti-diabetic drug gliclazide, and anti-hypertensive drug prazosin during 92 days of operation. At the same time, fluctuations were recorded for the methane gas production, and also the domination of acetic acid and propionic acid in the presence of pharmaceutical compounds was measured. The results from 16s rRNA sequencing revealed that these compounds stimulated the growth of hydrogenotrophic methanogens, mainly Methanobrevibacter and Methanobacterium, while shifting the compositions of hydrolytic and fermentative bacteria. These outcomes proved the capability of the pharmaceutical compounds to influence the process performance by changing the microbial compositions in the anaerobic reactor.

Impact of Pharmaceutical Compounds in the Bioremediation of Municipal Biosolids by the White-Rot-Fungi Trametes hirsuta.

The potential of microorganisms for the treatment of municipal biosolids is continuously growing. The present studies evaluated the potency of Trametes hirsuta for the reduction in biosolid mass, production of extracellular enzymes, and removal of pharmaceutical compounds (PhACs) in biosolid slurry in the presence and absence of spiked PhACs [5 non-steroidal anti-inflammatories (NSAIs) and 2 psychoactive compounds (PACs)]. Toxicity after 35 days of fungal treatment was also assessed. Results showed that the growth of T. hirsuta is limited above 25% and wholly inhibited above 50% of biosolids in the slurry. At 12% of biosolid concentration, biosolid mass was reduced by 90%, NSAIs were entirely removed, but PACs' removal was only ~20%. Increasing biosolid content to 25% did not markedly affect biosolid reduction but significantly enhanced the removal of PACs (>50%). Results also showed that both PhACs and biosolids induced the production of oxidative enzymes. In 12% biosolids in the slurry, the oxidative potential measured by the ABTS assay (OABTS) reached 5,000 mM of OABTS in the presence of PhACs, and 2,500 mM of OABTS without PhACs, as compared to 1,200 mM of OABTS in control culture. Finally, we report that white rot fungi (WRF) treatment significantly decreased the toxicity of the biosolids.

Kinetics, mechanism studies and antibacterial activity of pharmaceutical Sulfaguanidine under light irradiation in aqueous solution

The presence of pharmaceutical compounds in the environment worries several researchers for several years since their existence in aquatic systems leads to major environmental problems. These compounds are a unique category of pollutants and considered emerging contaminants in water supply systems. They have been found in groundwater and even in drinking water at concentrations ranging from ng to µg/L.In the present work, we investigated the photochemical behavior of a sulfonamide antibiotic, namely sulfaguanidine (SGD) in aqueous solutions as a function of pH and we examined the inhibitory activity of photoproducts SDG against E coli BLSE and S. aureus using the disc diffusion method, determination of minimum inhibitory concentration and cell viability percentage. Quantum yields were measured at 254 and 302 nm during irradiation in absence and presence of oxygen). In aerated conditions, they were evaluated to 2.3 x 10−2 and 2.5 x 10−3 respectively. However, the degradation process is not completely inhibited in the presence of oxygen due to sulfaguanidine photoreactivity, which is in agreement with the involvement of the singlet as well as the triplet excited states.Several photoproducts were elucidated using liquid chromatography coupled with positive mode mass spectroscopy LC/MS/ESI +. For bacterial activity, these photoproducts shows more toxic that the Sulfaguanidine and exhibited a higher inhibitory activity against E coli and S. aureus cells.

Insight on the development of molybdenum oxide-based photocatalyst towards pharmaceutical pollutants abatement

Abstract The presence of pharmaceutical compounds in the environment has given an unparallel impact on the human and environment. Till the present day, several methods have been imposed for the pharmaceutical pollutants’ removal. However, these methods suffer from some drawbacks which limited their application in wastewater treatment. As a new advanced technology, the photocatalysis method has been considered as an efficient method to eliminate the pharmaceutical pollutants in the water matrix. Molybdenum oxide (MoO3) photocatalyst has captivated global interest due to its non-toxicity, good thermal and chemical stability, and remarkable optical properties. However, the limitations of MoO3material have hindered its theoretical performance in eliminating distinct pharmaceutical pollutants. Some modification strategies have been proposed for MoO3photocatalyst which results in the development of several modified MoO3photocatalysts towards a broad range of pharmaceutical pollutants removal.

In vitro genotoxic and mutagenic effects of water samples from Sapucaia and Esteio streams (Brazil) under the influence of different anthropogenic activities

Pollution of aquatic ecosystems is associated with the discharge of mainly industrial and urban effluents, which may cause damage to public health. This study aims to evaluate the cytotoxic, genotoxic, and mutagenic potential of surface water samples under the influence of different anthropogenic effluents in a human-derived liver cell line (HepG2). Samples were collected in Esteio and Sapucaia streams (Rio Grande do Sul; Brazil), which flow into the Sinos River, a source of water supply for more than one million people. Physicochemical and microbiological analyses were performed as well as an analysis of inorganic elements using the PIXE technique (Particle-Induced X-Ray Emission). The presence of pharmaceutical compounds and caffeine was evaluated by gas chromatography coupled to mass spectrometry. The cytotoxicity, genotoxicity, and mutagenicity of the samples were evaluated in HepG2 cells by cell viability assays, alkaline Comet Assay and Cytokinesis-block micronucleus (CBMN) assay. We verified alterations in the physicochemical and microbiological parameters and detected caffeine, diethyltoluamide, and different inorganic elements that corresponded to elements from domestic and industrial effluents and agricultural runoff. Although the samples in the concentration used were not cytotoxic, water samples from all sites induced DNA damage. However, it is difficult to attribute these damages to a specific substance since the factors are a complex mixture of different compounds. Despite this, it is observed that both urban and industrial contributions had a similar effect in the cells evaluated. Such results demonstrate the need to perform biomonitoring of surface waters under anthropogenic influence, especially those that flow into rivers that are a source of public supply water. We also highlight the need for research into emerging pollutants in these aquatic environments.

Ultra-high pressure liquid chromatography coupled to travelling wave ion mobility-time of flight mass spectrometry for the screening of pharmaceutical metabolites in wastewater samples: Application to antiretrovirals

The presence of pharmaceutical compounds in the aquatic environment is a significant environmental health concern, which is exacerbated by recent evidence of the contribution of drug metabolites to the overall pharmaceutical load. In light of a recent report of the occurrence of metabolites of antiretroviral drugs (ARVDs) in wastewater, we investigate in the present work the occurrence of further ARVD metabolites in samples obtained from a domestic wastewater treatment plant in the Western Cape, South Africa. Pharmacokinetic data indicate that ARVDs are biotransformed into several positional isomeric metabolites, only two of which have been reported wastewater samples. Given the challenges associated with the separation and identification of isomeric species in complex wastewater samples, a method based on liquid chromatography hyphenated to ion mobility spectrometry-high resolution mass spectrometry (LC-IMS-HR-MS) was implemented. Gradient LC separation was achieved on a sub-2 µm reversed phase column, while the quadrupole-time-of-flight MS was operated in data independent acquisition (DIA) mode to increase spectral coverage of detected features. A mass defect filter (MDF) template was implemented to detect ARVD metabolites with known phase I and phase II mass shifts and fractional mass differences and to filter out potential interferents. IMS proved particularly useful in filtering the MS data for co-eluting species according to arrival time to provide cleaner mass spectra. This approach allowed us to confirm the presence of two known hydroxylated efavirenz and nevirapine metabolites using authentic standards, and to tentatively identify a carboxylate metabolite of abacavir previously reported in literature. Furthermore, three hydroxylated-, two sulphated and one glucuronidated metabolite of efavirenz, two hydroxylated metabolites of nevirapine and one hydroxylated metabolite of ritonavir were tentatively or putatively identified in wastewater samples for the first time. Assignment of the metabolites is discussed in terms of high resolution fragmentation data, while collisional cross section (CCS) values measured for the detected analytes are reported to facilitate further work in this area.

Cysteine- and glycine-functionalized mesoporous silica as adsorbents for removal of paracetamol from aqueous solution

ABSTRACT The presence of pharmaceutical compounds in the environment is problem for human health worldwide. Paracetamol is one of the pharmaceutical compounds that is widely used as a pain reliever and fever reducer, and it has been discharged in water via industrial and domestic wastewater. This study aimed to improve the removal of paracetamol from aqueous solutions using two different amino-acid-modified mesoporous silica nanoparticles (MSNs). Two types of adsorbents were used: the surfaces of epoxy-modified MSNs were modified with glycine (MSN-Gly) and cysteine (MSN-Cys). Topographical images indicated that the size of fabricated nanoparticles ranged between 220 and 360 nm, with a pore size of ~5 nm. IR spectra confirmed the successful attachment of amino acids on MSN surfaces as a peak appeared at ~1720 cm−1, indicating a carbonyl group. A series of experiments were performed using the batch adsorption method to investigate the effects of contact time, initial concentration of the adsorbate, and pH on the removal of paracetamol from the aqueous solution. The adsorption capacity of paracetamol was higher in acidic media for both adsorbents. The maximum adsorbed amount of paracetamol was 300 mg/g for MSN-Gly compared with 250 mg/g for MSN-Cys. For both adsorbents and at all pH values, the experimental data were well matched with the pseudo-second order and the adsorption isotherm was fitted using a Temkin model.

Occurrence of Pharmaceutical Compounds in Groundwater from the Gran Canaria Island (Spain)

The presence of pharmaceutical compounds in the whole environment is a growing concern. These compounds might be present in the effluents of wastewater treatment plants and, hence, irrigation with treated sewage may be a source of groundwater pollution. The volcanic aquifer that lies NE of Gran Canaria (Spain) was studied to address the relationship of the occurrence of pharmaceutical compounds and a golf course that has been irrigated with regenerated water since 1973. Of the 14 analyzed groundwater samples, five wells were chosen to perform annual monitoring. Irrigation water and soil leachate were also evaluated. The target analytes were atenolol, metamizole, fluoxetine, ibuprofen, nicotine, permethrin, caffeine, and their metabolite paraxanthine. The environmental risk is limited as the concentrations of the pharmaceuticals measured in the sampled wells were always below 60 ng·L−1 (lower than the detected caffeine and nicotine concentrations). Wide variations for the same wells were measured among sampling campaigns, and also among the different wells. The study points to the importance of sample conservation during transport and the need to perform analyses immediately, or to follow an in-situ extraction procedure to carry concentrated samples under better conditions.