Β-blocker Atenolol Research Articles

Cytoskeletal disarray increases arrhythmogenic vulnerability during sympathetic stimulation in a model of hypertrophic cardiomyopathy

Familial hypertrophic cardiomyopathy (FHC) patients are advised to avoid strenuous exercise due to increased risk of arrhythmias. Mice expressing the human FHC-causing mutation R403Q in the myosin heavy chain gene (MYH6) recapitulate the human phenotype, including cytoskeletal disarray and increased arrhythmia susceptibility. Following in vivo administration of isoproterenol, mutant mice exhibited tachyarrhythmias, poor recovery and fatigue. Arrhythmias were attenuated with the β-blocker atenolol and protein kinase A inhibitor PKI. Mutant cardiac myocytes had significantly prolonged action potentials and triggered automaticity due to reduced repolarization reserve and connexin 43 expression. Isoproterenol shortened cycle length, and escalated electrical instability. Surprisingly isoproterenol did not increase CaV1.2 current. We found alterations in CaV1.2-β1 adrenergic receptor colocalization assessed using super-resolution nanoscopy, and increased CaV1.2 phosphorylation in mutant hearts. Our results reveal for the first time that altered ion channel expression, co-localization and β-adrenergic receptor signaling associated with myocyte disarray contribute to electrical instability in the R403Q mutant heart.

Review of 20-year results of ASCOT Legacy

The article presents the results of a 20-year follow-up of patients in the ASCOT Legacy study, indicating that antihypertensive and lipid-lowering therapy reduces mortality in patients with hypertension and high cardiovascular risk in the long term. In the group of patients treated with amlodipine compared with the β-blocker atenolol, there was a decrease in mean systolic and diastolic blood pressure (BP), as well as a long-term improve in the form of a decrease in the prevalence of cardiovascular events and mortality due to stroke. An important feature of therapy based on amlodipine was the reduction in BP variability. The article reflects the results of major studies that determine the possibility and effectiveness of early prescription of combined antihypertensive and lipid-lowering therapy.

Abstract A017: Lung cancer chemoprevention with the β-blocker carvedilol

Abstract Chronic exposure to carcinogens that are present in tobacco smoke is a causative factor for lung carcinogenesis. Although smoking cessation successfully reduced the prevalence of cigarette use in the US, lung cancer risk for current and former smokers remains high, for whom no effective chemopreventive agent currently exists. In the present study, carvedilol, an FDA-approved β-blocker was examined on lung carcinogenesis induced by the tobacco carcinogen benzo(a)pyrene [B(a)P] in vitro and in vivo. In non-tumorigenic human bronchial epithelial cell culture BEAS-2B, carvedilol inhibited benzo(a)pyrene diol epoxide (BPDE)-induced malignant transformation at non-toxic concentrations in a dose-dependent manner. Although β-adrenergic receptors (β-ARs) are expressed in BEAS-2B cells, the anticancer activity of carvedilol is independent of β-blockade since the non-β-blocking R-carvedilol enantiomer also blocked transformation while the β-blockers atenolol (β1-AR selective blocker), ICI-118,551 (β2-AR selective blocker), and propranolol (nonselective blocker) had no effect. Carvedilol’s anti-transformation activity is possibly mediated by aryl hydrocarbon receptor signaling because carvedilol, R- and S-carvedilol all inhibited B(a)P-activated xenobiotic responsive element (XRE) promoter and CYP1A1 mRNA expression. In a B(a)P-induced acute lung toxicity model in CD-1 mice, pretreatment with carvedilol, R- or S-carvedilol (20 mg/kg/day) for 7 days significantly attenuated increased plasma levels of lactate dehydrogenase and malondialdehyde, inflammatory cell infiltration, histopathologic changes, and overexpression of COX-2 in the lung. In a B(a)P-induced lung carcinogenesis model in A/J mice, carvedilol at 3.2 and 20 mg/kg significantly attenuated tumor multiplicity and burden, to a similar degree as the EGFR inhibitor gefitinib. Our study reveals a previously unexplored role for the FDA approved cardiovascular drug carvedilol in the prevention of tobacco carcinogen-associated lung cancer. Citation Format: Ayaz Shahid, Mengbing Chen, Carol Lin, Bradley T. Andresen, Cyrus Parsa, Robert Orlando, Ying Huang. Lung cancer chemoprevention with the β-blocker carvedilol [abstract]. In: Proceedings of the Second Biennial NCI Meeting: Translational Advances in Cancer Prevention Agent Development (TACPAD); 2022 Sep 7-9. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_2): Abstract nr A017.

Ti-based robust MOFs in the combined photocatalytic degradation of emerging organic contaminants

Photocatalysis process is a promising technology for environmental remediation. In the continuous search of new heterogeneous photocatalysts, metal–organic frameworks (MOFs) have recently emerged as a new type of photoactive materials for water remediation. Particularly, titanium-based MOFs (Ti-MOFs) are considered one of the most appealing subclass of MOFs due to their promising optoelectronic and photocatalytic properties, high chemical stability, and unique structural features. However, considering the limited information of the reported studies, it is a hard task to determine if real-world water treatment is attainable using Ti-MOF photocatalysts. In this paper, via a screening with several Ti-MOFs, we originally selected and described the potential of a Ti-MOF in the photodegradation of a mixture of relevant Emerging Organic Contaminants (EOCs) in real water. Initially, two challenging drugs (i.e., the β-blocker atenolol (At) and the veterinary antibiotic sulfamethazine (SMT)) and four water stable and photoactive Ti-MOF structures have been rationally selected. From this initial screening, the mesoporous Ti-trimesate MIL-100(Ti) was chosen as the most promising photocatalyst, with higher At or SMT individual photodegradation (100% of At and SMT photodegradation in 2 and 4 h, respectively). Importantly, the safety of the formed by-products from the At and SMT photodegradation was confirmed. Finally, the At and SMT photodegradation capacity of MIL-100(Ti) was confirmed under realistic conditions, by using a mixture of contaminants in tap drinking water (100% of At and SMT photodegradation in 4 h), proven in addition its potential recyclability, which reinforces the potential of MIL-100(Ti) in water remediation.

Evaluation of an electrochemical membrane reactor for the removal of β-blocker compound from water

As part of the Brazilian Popular Pharmacy Program, the β-blocker Atenolol (ATN) is widely used, and its presence in the environmental ecosystems is a reality. Aiming the ATN removal, the use of an electrochemical membrane reactor was evaluated and compared to a membraneless one. The results show that the generation of SO4•− in the membrane reactor occurs by the reaction of HSO4−/H2SO4 scavenging HO•, whereas, in the membraneless reactor, the SO4•− generation occurs mainly by the direct oxidation mechanism. Operating both reactors in the same hydrodynamic conditions, it was found that the concentrations of SO4•− and S2O82− are higher in the membrane reactor, leading to a greater concentration of these species being transported to the bulk solution, changing the kinetics, and presenting better results in electrochemical combustion (ϕ), mineralization current efficiency (MCE) and specific energy consumption (Es). Since the mass transport limitations were overcome in membrane reactor, the processes may find their good applications in water and wastewater treatment.

Investigating the biological degradation of the drug β-blocker atenolol from wastewater using the SBR.

Drug compounds are one of the main contributors to the entry of micro-pollutants into the environment, known as a constant threat to environmental stability. Atenolol is a type of beta-blocker extensively used to cure cardiovascular disorders. The residues of this compound have been continuously detected in aquatic environments because it is a polar and poorly biodegradable compound. Thus, removing atenolol from wastewater is essential before discharging into the environment. Biological processes are considered the most important removal process for polar drugs in wastewater treatment plants. Accordingly, for the first time in this study, the SBR performance was investigated in the biodegradation and mineralization of atenolol under different concentrations (50-600mg/L) and hydraulic retention times (48-32h). Based on the results, the time required for the acclimation of biomass to atenolol (C: 50mg/L and the HRT: 48h) was 80 days. The SBR efficiencies under optimum conditions (C: 400mg/L and HRT: 40h) in removing the atenolol and COD were 91% and 87%, respectively. For the first time in this study, one of the main pathways of the atenolol biodegradation was identified. Based on the review and comparison of the results of this study with existing literature showing that the SBR used in this study was able to remove higher concentrations with better efficiencies than other processes. Therefore, it can be concluded that the SBR used in this study could be considered an efficient and promising technique for treating wastewaters containing atenolol and other beta-blocker group drugs.

Functional network analysis reveals potential repurposing of β-blocker atenolol for pancreatic cancer therapy.

The survival rate of patients with pancreatic cancer is low; therefore, continuous discovery and development of novel pancreatic cancer drugs are required. Functional network analysis is an integrated bioinformatics approach based on gene, target, and disease networks interaction, and it is extensively used in drug discovery and development. This study aimed to identify if atenolol, a selective adrenergic inhibitor, can be repurposed for the treatment of pancreatic cancer using functional network analysis. Direct target proteins (DTPs) and indirect target proteins (ITPs) were obtained from STITCH and STRING databases, respectively. Atenolol-mediated proteins (AMPs) were collected from DTPs and ITPs and further analyzed for gene ontology, KEGG pathway enrichment, genetic alterations, overall survival, and molecular docking. We obtained 176 AMPs that consisted of 10 DTPs and 166 ITPs. Among the AMPs involved in the pancreatic cancer pathways, several AMPs such as MAPK1, RELA, MAPK8, STAT1, and STAT3 were identified. Genetic alterations in seven AMPs were identified in 0.9%-16% of patients. Patients with high mRNA levels of MAPK1, RELA, STAT3, GNB1, and MMP9 had significantly worse overall survival rates compared with patients with low expression. Molecular docking studies showed that RELA and MMP9 are potential target candidates of atenolol in the treatment of patients with pancreatic cancer. In conclusion, atenolol can potentially be repurposed to target pancreatic cancer cells by modulating MMP9 and NF-κB signaling. The results of this study need to be further validated in vitro and in vivo.

Metoprolol rescues endothelial progenitor cell dysfunction in diabetes.

Added risk portended by diabetes in addition to hypertension has been related to an amplification of endothelial dysfunction. β-blockers are widely used for cardiovascular diseases and improve the endothelial function compared with a placebo. However, the effect of β-blockers on the endothelial progenitor cells (EPCs) function in diabetes is still unknown. Five β-blockers (metoprolol, atenolol, propranolol, bisoprolol, and nebivolol) were tested in EPC functional screening. Metoprolol improved EPC function significantly among the five β-blockers and was chosen for the in vivo tests in STZ induced diabetic mice. Reactive hyperemia peripheral arterial tonometry (RH-PAT) measurements were performed using the Endo-PAT2000 device in diabetic patients. Metoprolol, but not other β-blockers, improved EPC function in both tube formation and migration assay. EPC function was significantly decreased in diabetic mice, and metoprolol treatment restored damaged EPC migration capabilities and circulation EPC number. Metoprolol treatment promoted wound healing and stimulated angiogenesis in diabetic mice. Furthermore, metoprolol significantly enhanced eNOS phosphorylation and decreased O2− levels in EPCs of diabetic mice. In clinical trials, the RH-PAT index was significantly higher in metoprolol-treated versus bisoprolol-treated diabetics. Metoprolol could accelerate wound healing in diabetic mice and improve endothelial function in diabetic subjects, which may be mediated in part by improving impaired EPC function.

Influence of the reactor configuration and the supporting electrolyte concentration on the electrochemical oxidation of Atenolol using BDD and SnO2 ceramic electrodes

Electrochemical oxidation of β-blocker atenolol (ATL, 100 ppm) at different applied current densities (33, 50 and 83 mA·cm−2) using a reactor divided by an ion-exchange membrane and an undivided one was investigated. Two types of anodes were used for this purpose: a boron-doped diamond (BDD) anode and new low-cost ceramic electrodes made of tin dioxide doped with antimony (Sb-doped SnO2). Degradation was assessed using a high performance liquid chromatography, while mineralization by measuring total organic carbon (TOC) dissolved in sample. Except for the lowest current density, ATL was completely degraded for both reactors and electrodes. The highest percentage of TOC eliminated (89%) was obtained at the highest applied current density with the BDD electrode in the divided reactor. The presence of the cation-exchange membrane prevented the reduction of both the electrogenerated oxidizing species and the oxidized organic compounds and enhances the electro-oxidation kinetic reaction.In order to study the influence of the supporting electrolyte, three different concentrations of sodium sulfate (0.014, 0.05 and 0.1 M) were tested in the undivided reactor with both electrodes. The results showed that an increase in the concentration of the supporting electrolyte improves the mineralization of ATL for the BDD electrode and, on the contrary, worsens for the ceramic electrode. Accelerated service life tests were carried out for the ceramic electrode at 100 mA·cm−2 in 0.5 M H2SO4. Ecotoxicity tests using marine bacteria (Vibrio Fischeri) revealed that no toxic by-products were formed in any case.

Mechanisms for degradation and transformation of β-blocker atenolol via electrocoagulation, electro-Fenton, and electro-Fenton-like processes

This study investigated the mechanism of atenolol degradation and transformation through ˙OH-based electro-Fenton (EF), SO4˙−-based EF-like, and electrocoagulation (EC) processes.

The selection of β-blocker after successful reperfusion in patients with ST-elevation myocardial infarction.

The selection of β-blocker for survivors after primary intervention due to acute ST-elevation myocardial infarction seems crucial to improve the outcomes. However, rare comparison data existed for these patients. We aimed to compare the effectiveness of selective β-blockers to that of carvedilol in patients treated with primary intervention. Among the 1,485 patients in the "INTERSTELLAR" registry between 2007 and 2015, 238 patients with selective β-blockers (bisoprolol, nebivolol, atenolol, bevantolol, and betaxolol) and 988 with carvedilol were included and their clinical outcomes were compared for a 2-year observation period. In the clinical baseline characteristics, the unfavorable trends in the carvedilol group were high Killip presentation, lower ejection fractions, smaller diameters, and longer lengths of deployed stents. Although mortality (2.5% vs. 1.7%; p = 0.414) and the rate of stroke (0.8% vs. 0.6%; p = 0.693) were not different between groups, the rate of recurrent myocardial infarction (4.6% vs. 1.2%; p = 0.001) and of target vessel revascularization (4.2% vs. 0.9%; p < 0.001) were lower in the carvedilol group. After eliminating the difference by propensity matching, the similar outcome result was shown (all-cause death, 0.6% vs. 1.0%, p = 0.678; stroke, 0.6% vs. 1.2%, p = 0.479; myocardial infarction, 5.0% vs. 1.2%, p = 0.003; target vessel revascularization, 4.5% vs. 0.7%, p < 0.006) for 595 matched populations. The use of carvedilol was also determined to be an independent predictor for recurrent myocardial infarctions (hazard ratio = 0.305; p = 0.005; 95% confidence interval = 0.13-0.69). Use of a carvedilol in ST-segment myocardial infarction survivor is associated with lower recurrent myocardial infarction events. Thus, it might be the better choice of β-blocker for secondary prevention in ST-elevation myocardial infarction patients treated with primary percutaneous coronary intervention.

Biological sample preparation by using restricted-access nanoparticles prepared from bovine serum albumin: application to liquid chromatographic determination of β-blockers.

Restricted-access nanoparticles (RANPs) were prepared from bovine serum albumin by coacervation. They have an average sized of 311nm. They were characterized and used to capture the β-blockers atenolol, metoprolol and propranolol from untreated biological samples. It is shown that both high protein affinity drugs (propranolol) and low protein affinity drugs (atenolol) could be rapidly extracted from plasma. This is revealed by kinetic and isothermal adsorption studies. On the other hand, almost all proteins from the sample were excluded. This demonstrates the efficiency of RANPs as restricted-access material. Sample preparation was carried out by solid phase microextraction using a probe obtained by the fixation of the RANPs at the end of a glass capillary. Atenolol (in concentrations from 100 to 1200μgL-1), metoprolol (from 80 to 1000μgL-1) and propranolol (from 15 to 200μgL-1) were extracted from spiked plasma samples and analyzed by LC MS/MS without using a separation column. Correlation coefficients >0.99, good precision, accuracy, robustness, and lack of memory effects were observed for all of the analytes. The detection limits (at an S/N of 3) are 25.6, 14.6, and 3.8μgL-1 for atenolol, metoprolol and propranolol, respectively. Ten samples can be simultaneously extracted within ∼15min. Plasma samples of patients undergoing medical treatment were successfully analyzed with the method. Graphical abstract Schematic representation of a bovine serum albumin-based restricted access nanoparticle that exclude proteins from a human plasma sample butcapture the small analytes.

Oxidation of β-blocker atenolol by a combination of UV light and chlorine: Kinetics, degradation pathways and toxicity assessment

Degradation of atenolol (ATL) was achieved using combination of UV and chlorine treatment (UV/chlorine). Factors affecting ATL degradation, such as pH, chlorine dosage, common anions and natural organic matter (NOM), were systematically studied. ATL degradation could be described by the pseudo-first-order reaction kinetics. Combination of UV-254 nm and 100 μM of chlorine at pH 7 demonstrated 93.5% removal of 10 μM of ATL within 20 min. Radical scavenging tests indicated that both hydroxyl radicals (OH) and reactive chlorine species (RCS) participated in ATL degradation by UV/chlorine. The highest degradation rate was achieved at acidic pH. The contribution of RCS towards ATL degradation elevated as pH value increased. ATL degradation rate constant directly correlated with chlorine dosage in the 0–100 μM range. Scavenging effect of the excess chlorine occurred above 200 μM. HCO3− and NOM presence negatively affected ATL degradation, while Br− had a positive effect. Presence of Cl− had no noticeable impact on ATL degradation. Several ATL degradation pathways were proposed based on analysis of intermediate degradation products obtained using LC/MS/MS technique. Five typical disinfection byproducts including trichloromethane, dichloroacetaldehyde, trichloroacetonitrile, trichloroacetaldehyde and dichloroacetonitrile were detected. Although some intermediate products could potentially be more toxic than ATL, they were very likely further oxidized forming products with lower toxicity. In general, we demonstrated that UV/chlorine AOP is an effective approach to purify ATL contaminated water.

Growth Stimulation Effects of Environmentally Realistic Contaminant Mixtures on a Marine Diatom.

To estimate mixture effects caused by the high number of chemicals simultaneously present in the environment, methods for routine effect assessment of environmentally realistic contaminant mixtures are needed. We repeatedly exposed the marine diatom Phaeodactylum tricornutum to SpeediskTM passive sampler extracts and observed statistically significant growth stimulation up to 6 and 7% for samples from inside and outside the harbor of Zeebrugge, respectively. These effects were found at summed contaminant concentrations (159-166ngL-1 ) that were within a 1.1-to2.4-fold range of those observed in grab water samples taken during sampler deployment. These stimulatory effects were confirmed in 2 independent tests with extracts stored for <1or8mo that had undergone limited sample handling, whereas no effects were observed for extracts that had been stored for 16mo that had undergone repeated handling (notably repeated freezing and thawing) before biotest spiking. Targeted analysis by ultra-high performance liquid chromatography was performed to quantify 88 personal care products (n = 8), pesticides (n = 28), and pharmaceuticals (n = 52). Among these compounds, multivariate statistical analysis put forward the β-blocker atenolol as explaining most of the observed variation in mixture composition between the growth-stimulating and no effect-causing extracts. However, when tested individually over the entire concentration range present in the extracts, atenolol did not have any effect on P.tricornutum, suggesting that nontargeted substances in the extracts may have contributed to the observed stimulatory effects. Nevertheless, the present study shows that exposure to contaminant mixtures at environmentally realistic concentrations can lead to small but significant growth stimulation effects on the marine diatom P. tricornutum. Environ Toxicol Chem 2019;38:1313-1322. © 2019 SETAC.

Bioactivity-HiTES Unveils Cryptic Antibiotics Encoded in Actinomycete Bacteria.

Bacteria harbor an immense reservoir of potentially new and therapeutic small molecules in the form of "silent" biosynthetic gene clusters (BGCs). These BGCs can be identified bioinformatically but are sparingly expressed under normal laboratory growth conditions, or not at all, and therefore do not produce significant levels of the corresponding small molecule product. Several methods have been developed for activating silent BGCs. A major limitation for nearly all methods is that they require genetic procedures and/or do not report on the bioactivity of the cryptic metabolite. We herein report "Bioactivty-HiTES", an approach that links the bioactivity of cryptic metabolites to their induction while at the same time obviating the need for genetic manipulations. Using this method, we detected induction of cryptic antibiotics in three actinomycete strains that were tested. Follow-up studies in one case allowed us to structurally elucidate two cryptic metabolites, elicited by the β-blocker atenolol in Streptomyces hiroshimensis, with selective growth-inhibitory activity against Gram-negative bacteria, notably Escherichia coli and Acinetobacter baumannii. Atenolol turned out to be a global elicitor of secondary metabolism, and characterization of additional cryptic metabolites led to the discovery of a novel naphthoquinone epoxide. Bioactivity-HiTES is a general, widely applicable procedure that will be useful in identifying cryptic bioactive metabolites in the future.

Oxidative treatments for atenolol removal in water: Elucidation by mass spectrometry and toxicity evaluation of degradation products.

The presence of pharmaceuticals in water is a worldwide concern due to potential damage to human and environmental health. For example, compounds such as the β-blocker atenolol (ATE), widely used for the treatment of cardiac disease, are detected in drinking water since conventional water treatment plants are not designed to remove them. Thus, the evaluation of ATE removal at different water oxidative treatment processes, identification of its degradation products and evaluation of their toxicity is necessary. Aqueous solutions of ATE (10 mg/L) were submitted to oxidative treatments of chlorination ([NaClO] = 10 mg/L), ozonation ([O3 ] = 8 mg/L), photocatalysis ([TiO2 ] = 120 mg/L and UV-C light) and photolysis (UV-C light). The removal of ATE and formation of degradation products (DPs) were monitored by mass spectrometry. To assess acute cytotoxicity, DPs were submitted to colorimetric MTT assay using HepG2 cells. The Ecological Structure Activity Relationships (ECOSAR) software was applied to estimate the acute and chronic toxicity of identified DPs at different trophic levels. Photocatalysis was the treatment that demonstrated greater efficiency, removing 94% of the initial ATE. For the four tested treatments, 12 DPs were confirmed after 30 min. Moreover, some of the identified DPs were unpublished in the literature. Through high-resolution mass spectrometry (HRMS), it was possible to elucidate the structure of the DPs. Solutions of DPs were not considered to be toxic to HepG2 cells. Only the DP with a molecular formula of C13 H19 NO3 (m/z 238.1438) could be considered detrimental to daphnid and green algae. Low rates of organic matter removal and high rates of ATE degradation were obtained in the applied treatments after 30 min. Although the treated solutions were not toxic to HepG2 cells, one of the degradation products can be considered an environmental concern since it presents chronic toxicity to daphnid and green algae.

Apple tree branches derived activated carbons for the removal of β-blocker atenolol

This work approaches the preparation of KOH and K2CO3 activated carbons from apple tree small branches char with activation yields around 40%, and apparent surface areas up to 2472 m2 g−1. The treatment duration had a marked impact on the micropore structure, causing the widening of the narrow micropores to supermicropores.The adsorption characteristics of lab-made carbons for atenolol removal from aqueous phase was assessed by kinetic and equilibrium experiments. Monolayer adsorption capacities between 346 and 556 mg g−1 were achieved.The commercial atenolol, consisting in a racemic mixture, gave rise to a two-step thermal decomposition process. Thermogravimetric analysis of the exhausted samples revealed that the predominant atenolol specie adsorbed is conditioned by the carbons’ surface chemistry: neutral/acidic lab-made carbons generally favoured the decomposition of the more stable specie; basic commercial samples retained predominantly the less stable one.

Study of pharmaceuticals in surface and wastewater from Cuernavaca, Morelos, Mexico: Occurrence and environmental risk assessment

The present work describes the first known study to date on the occurrence of pharmaceuticals in surface water and wastewater of Cuernavaca, the capital of the state of Morelos (México). Selected pharmaceuticals (a total of 35) were extracted from the collected water samples with a generic solid phase extraction (SPE) protocol and determined in the sample extracts by means of high-performance liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS). A screening level risk assessment combining the measured environmental concentrations (MECs) with dose-response data based on predicted no-effect concentrations (PNECs) was also applied to estimate Hazard Quotients (HQs) for the pharmaceuticals detected in the investigated area. A total of twelve pharmaceuticals were found in the water samples analyzed, with detection frequencies above 78% and in most cases of 100%. Overall, the most abundant pharmaceuticals in surface water were the analgesic and anti-inflammatory drugs naproxen (732–4880ng/L), acetaminophen (354–4460ng/L), and diclofenac (258–1398ng/L), and the lipid regulator bezafibrate (286–2100ng/L). On the contrary, other compounds like the β-blocker atenolol and the psychiatric drug carbamazepine were found at only a few ng or tens of ng per liter in the Apatlaco River. Despite the fact that some of the most abundant compounds showed good removal (>97%) during wastewater treatment, concentrations downstream the WWTP were only slightly lower than upstream. This indicates the existence of additional inputs of untreated wastewater into the river. Based on the obtained HQ-values, the concentrations of ibuprofen, sulfamethoxazole, diclofenac and naproxen present in the river could pose a high toxicity risk for the aquatic ecosystem. These findings highlight these pharmaceuticals as relevant organic contaminants in the area of study and the need to further monitor them in order to adopt appropriate measures to safeguard the ecosystem, and eventually human health.

Behavior of pharmaceuticals in UV photoreactors fed with sewage treated by anaerobic/aerobic system

ABSTRACTThis work has assessed the seasonal changes and the dynamics in the concentration of six pharmaceutical compounds during photolysis as a tertiary treatment of sewage previously treated by an anaerobic/aerobic system comprising a UASB (Upflow Anaerobic Sludge Blanket) reactor and a trickling filter (TF). The target compounds were four antibiotics (ciprofloxacin (CPF), clindamycin (CLM), sulfamethoxazole (SMX), and trimetoprim), one β-blocker (atenolol), and one anti-inflammatory (diclofenac (DCF)). Six hydraulic retention times (HRTs) were evaluated (5, 10, 20, 40, 80, and 160 min) with the intent of varying the ultraviolet C (UVC) radiation doses applied to the effluent from biological treatment containing the target contaminants. The concentrations of pharmaceutical compounds in the effluent of the UASB/TF system were in agreement with the concentration levels reported in the literature. Aside from DCF, the seasonality seems to be a preponderant characteristic regarding the pharmaceutical concentration found in the effluent of biological treatment systems. The radiation dose of 117 mJ cm−2 seemed to be most suited for the photolysis application to tertiary treatment of domestic effluents. It was observed that lower UVC doses led to deconjugation of pharmaceuticals, which can result in increased concentrations of target pollutants in the photoreactor effluent.

H2Ti3O7 Nanotubes Decorated with Silver Nanoparticles for Photocatalytic Degradation of Atenolol

The photocatalytic degradation/adsorption process of the β-blocker atenolol (ATL) under UV irradiation is described using two types of silver decorated catalysts: silver/titania and silver/titanates. The silver ions were reduced on the surface of TiO2-P25-Degussa using gallic acid. Silver/titanates were prepared by a microwave-assisted hydrothermal method using the silver/titania as the starting material to obtain the hydrogen titanate (H2Ti3O7) structure with tubular morphology. These materials were characterized by X-ray diffraction, UV-Vis spectroscopy, N2 physisorption, temperature programmed reduction, TEM, and FTIR spectroscopy. During the photocatalytic process, the ATL molecules were completely converted to amino-diol byproducts. It is the first time that these materials have been applied during the photocatalytic process in the degradation of pharmaceuticals products. The success of the silver nanoparticles (2 nm) consists of the homogeneous distribution over the surface of titanate nanotubes inhibiting the hole/electron recombination promoting the oxidation process. The Ag@H2Ti3O7 with a concentration of silver as 1.0% shows the highest adsorption/degradation of ATL than the Ag@TiO2 and the P25-Degussa. The great performance in the reuse test consists in the strong attachment of the silver nanoparticles on the titanium surface that inhibits the silver lixiviation during the photocatalytic tests.