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1.
Microb Drug Resist ; 30(3): 118-126, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38330414

ABSTRACT

Nontyphoid salmonella can cause severe infections in newborns and is therefore declared a pathogen of major health significance at this age. The aim of the study was molecular and antimicrobial characterization of ß-lactamase-producing Salmonella Mikawasima outbreak clone on a Neonatal ward, University Hospital of Split (UHS), Croatia during the COVID-19 pandemic. From April 2020, until April 2023, 75 nonrepetitive strains of Salmonella Mikawasima were isolated from stool specimens and tested for antimicrobial resistance. All 75 isolates were resistant to ampicillin and gentamicin, while 98% of isolates were resistant to amoxicillin/clavulanic acid. A high level of resistance was observed to third-generation cephalosporins (36% to ceftriaxone and 47% to ceftazidime). Extended-spectrum ß-lactamase production was phenotypically detected by double-disk synergy test in 40% of isolates. Moderate resistance to quinolones was detected; 7% of isolates were resistant to pefloxacin and ciprofloxacin. All isolates were susceptible to carbapenems, chloramphenicol, and co-trimoxazole. Fourteen representative isolates, from 2020, 2021, 2022, and 2023, were analyzed with PFGE and all of them belong to the same clone. Whole-genome sequencing (WGS) analysis of three outbreak-related strains (SM1 and SM2 from 2020 and SM3 from 2023) confirmed that these strains share the same serotype (Mikawasima), multilocus sequence typing profile (ST2030), resistance genes [blaTEM-1B, aac(6')-Iaa, aac(6')-Im, and aph(2'')-Ib)] and carry incompatibility group C (IncC) plasmid. Furthermore, the gene blaSHV-2 was detected in SM1 and SM2. In summary, WGS analysis of three representative strains clearly demonstrates the persistence of ß-lactamase-producing Salmonella Mikawasima in UHS during the 4-year period.


Subject(s)
COVID-19 , Salmonella enterica , Infant, Newborn , Humans , Anti-Bacterial Agents/pharmacology , Serogroup , Pandemics , Salmonella enterica/genetics , Microbial Sensitivity Tests , COVID-19/epidemiology , Salmonella , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Hospitals
2.
Acta Pharm ; 73(4): 673-689, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38147479

ABSTRACT

This observational, cross-sectional study conducted at the University Hospital Centre Zagreb (UHC Zagreb) aimed to explore patients' beliefs about adjuvant endocrine therapy (AET) as well as their association with non-adherence and sociodemographic and clinical factors. Out of 420 early breast cancer (BC) patients included in the study, 79.5 % perceived AET necessary and important for their health, as measured by the Belief About Medicines Questionnaire (BMQ), with the mean necessity score (20.4 ± 3.68) significantly higher than the mean concerns score (13 ± 4.81) (p < 0.001). Based on the Medication Adherence Report Scale (MARS-5), 44.4 % (n = 182) of the participants were non-adherers, out of which 63.2 % (n = 115) were unintentional and 36.8 % (n = 67) intentional non-adherers. Significantly higher concern beliefs were found among patients that were younger (p < 0.001), employed (p < 0.001), intentionally non-adherent to AET (p = 0.006), had a lower body-mass index (p = 0.005) and a higher level of education (p < 0.001), were premenopausal at the time of diagnosis (p < 0.001), taking tamoxifen treatment (p = 0.05) and receiving ovarian suppression (p < 0.001). Younger patients should be recognized as being at risk of non-adherence as they hold greater concern beliefs about medicines.


Subject(s)
Breast Neoplasms , Cancer Survivors , Humans , Female , Breast Neoplasms/drug therapy , Cross-Sectional Studies , Croatia , Medication Adherence , Surveys and Questionnaires , Health Knowledge, Attitudes, Practice
4.
J Hazard Mater ; 454: 131478, 2023 07 15.
Article in English | MEDLINE | ID: mdl-37116332

ABSTRACT

Bisphenols are widely recognised as toxic compounds that potentially threaten the environment and public health. Here we report the use of cold atmospheric pressure plasma (CAP) to remove bisphenol A (BPA) and bisphenol S (BPS) from aqueous systems. Additionally, methanol was added as a radical scavenger to simulate environmental conditions. After 480 s of plasma treatment, 15-25 % of BPA remained, compared to > 80 % of BPS, with BPA being removed faster (-kt = 3.4 ms-1, half-life = 210 s) than BPS (-kt = 0.15 ms-1, half-life 4700 s). The characterisation of plasma species showed that adding a radical scavenger affects the formation of reactive oxygen and nitrogen species, resulting in a lower amount of ˙OH, H2O2, and NO2- but a similar amount of NO3-. In addition, a non-target approach enabled the elucidation of 11 BPA and five BPS transformation products. From this data, transformation pathways were proposed for both compounds, indicating nitrification with further cleavage, demethylation, and carboxylation, and the coupling of smaller bisphenol intermediates. The toxicological characterisation of the in vitro HepG2 cell model has shown that the mixture of transformation products formed during CAP is less toxic than BPA and BPS, indicating that CAP is effective in safely degrading bisphenols.


Subject(s)
Benzhydryl Compounds , Hydrogen Peroxide , Benzhydryl Compounds/toxicity , Benzhydryl Compounds/metabolism , Phenols/toxicity , Phenols/metabolism
5.
Environ Res ; 227: 115790, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37003551

ABSTRACT

This study investigated the bio-degradation kinetics of tetramethyl bisphenol F (TMBPF), a non-estrogenic alternative to bisphenol A (BPA). Batch biotransformation experiments were performed whereby samples were inoculated with activated sludge and analysed using liquid chromatography-Orbitrap-tandem mass spectrometry (LC-Orbitrap-MS) utilising two non-targeted workflows (commercial and freely available online) for biotransformation products (BTP) identification. The degradation of TMBPF followed single first-order reaction kinetics and depended on the initial concentration (ci) with faster degradation -kt = 0.16, (half-life = 4.4 days) at lower concentrations ci = 0.1 mg L-1, compared with -kt = 0.02 (half-live = 36.4 days) at ci = 10.0 mg L-1. After 18 days, only 8% of the original TMBPF remained at the lowest tested concentration (0.1 mg L-1). Twelve BTPs were identified, three of which were workflow and one condition-specific. The highest relative quantities of BTPs were observed in nutrient-mineral and mineral media after ten days, while after 14 days, 36 and 31% of TMBPF (ci = 1 mg L-1) remained in the nutrient-mineral and mineral media, respectively. Also, the kinetics of TMBPF and its BTPs were the same with and without an additional carbon source. A newly proposed biodegradation pathway for TMBPF involves cleavage of the methylene bridge, hydroxylation with further oxidation, sulphation, nitrification, nitro reduction with further oxidation, acetylation, and glycine conjugation, providing a deeper insight into the fate of TMBPF during biological wastewater treatment.


Subject(s)
Sewage , Wastewater , Biotransformation , Biodegradation, Environmental , Kinetics
6.
J Hazard Mater ; 448: 130964, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36860048

ABSTRACT

As population growth and climate change add to the problem of water scarcity in many regions, the argument for using treated wastewater for irrigation is becoming increasingly compelling, which makes understanding the risks associated with the uptake of harmful chemicals by crops crucial. In this study, the uptake of 14 chemicals of emerging concern (CECs) and 27 potentially toxic elements (PTEs) was studied in tomatoes grown in soil-less (hydroponically) and soil (lysimeters) media irrigated with potable and treated wastewater using LC-MS/MS and ICP-MS. Bisphenol S, 2,4 bisphenol F, and naproxen were detected in fruits irrigated with spiked potable water and wastewater under both conditions, with BPS having the highest concentration (0.034-0.134 µg kg-1 f. w.). The levels of all three compounds were statistically more significant in tomatoes grown hydroponically (

Subject(s)
Drinking Water , Solanum lycopersicum , Chromatography, Liquid , Tandem Mass Spectrometry , Wastewater
7.
Molecules ; 27(23)2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36500727

ABSTRACT

This study analyzed 16 bisphenols (BPs) in wastewater and sludge samples collected from different stages at a municipal wastewater treatment plant based on sequencing batch reactor technology. It also describes developing an analytical method for determining BPs in the solid phase of activated sludge based on solid-phase extraction and gas chromatography-mass spectrometry. Obtained concentrations are converted into mass flows, and the biodegradation of BPs and adsorption to primary and secondary sludge are determined. Ten of the sixteen BPs were present in the influent with concentrations up to 434 ng L-1 (BPS). Only five BPs with concentrations up to 79 ng L-1 (BPA) were determined in the plant effluent, accounting for 8 % of the total BPs determined in the influent. Eleven per cent of the total BPs were adsorbed on primary and secondary sludge. Overall, BPs biodegradation efficiency was 81%. The highest daily emissions via effluent release (1.48 g day-1) and sludge disposal (4.63 g day-1) were for BPA, while total emissions reached 2 g day-1 via effluent and 6 g day-1 via sludge disposal. The data show that the concentrations of BPs in sludge are not negligible, and their environmental emissions should be monitored and further studied.


Subject(s)
Water Pollutants, Chemical , Water Purification , Water Pollutants, Chemical/analysis , Benzhydryl Compounds/analysis , Phenols/analysis , Sewage/analysis , Waste Disposal, Fluid
8.
Sci Total Environ ; 837: 155707, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35537510

ABSTRACT

Developing novel, fast and efficient ecologically benign processes for removing organic contaminants is important for the continued development of water treatment. For this reason, this study investigates the implementation of Cold Atmospheric pressure Plasma (CAP) generated in ambient air as an efficient tool for the removal of Bisphenol A (BPA) and Bisphenol S (BPS)-known endocrine disrupting compounds in water and wastewater, by monitoring degradation kinetics and its transformation products. The highest removal efficiencies of BPA (>98%) and BPS (>70%) were obtained after 480 s of CAP exposure. A pseudo-first-order kinetic revealed that BPA (-kt = 4.4 ̶ 9.0 ms-1) degrades faster than BPS (-kt = 0.4 ̶ 2.4 ms-1) and that the degradation is also time- and CAP power-dependent, while the initial concentration or matrix type had a negligible effect. This study also tentatively identified three previously reported and one novel transformation product of BPA and four novel transformation products of BPS. Their postulated structures suggested similar breakdown mechanisms, i.e., hydroxylation followed by ring cleavage. The results demonstrate that CAP technology is an effective process for the degradation of both BPA and BPS without the need for additional chemicals, indicating that CAP is a promising technology for water and wastewater remediation worthy of further investigation and optimization.


Subject(s)
Plasma Gases , Water Pollutants, Chemical , Atmospheric Pressure , Benzhydryl Compounds/analysis , Phenols , Wastewater/chemistry , Water Pollutants, Chemical/analysis
9.
Chemosphere ; 271: 129786, 2021 May.
Article in English | MEDLINE | ID: mdl-33548857

ABSTRACT

High rate algal ponds (HRAP) are an alternative to conventional wastewater treatment with the potential for wastewater and biomass reuse. In this study, we report the development and validation of methods for analysing 18 bisphenols (BPs) in the aqueous and biomass phase of HRAP. For aqueous phase samples, obtained LLOQ ranged from 10 to 30 ng/L, and recoveries from 78% to 106%. The relative expanded uncertainty was highest at the lowest spiking level (100 ng/L) and ranged from 27% to 66% (BPA), while for the biomass, the LLOQ ranged from 25 to 75 ng/g dw, recoveries from 84% to 103%. The uncertainty ranged from 16% to 37% (BPA). On average, the influent contained 329, 144, and 21 ng/L of BPA, BPS and 4,4'-BPF, and the effluent 69 ng/L, 94 ng/L and

Subject(s)
Ponds , Water Purification , Benzhydryl Compounds/analysis , Biomass , Waste Disposal, Fluid , Wastewater
10.
J Appl Genet ; 62(2): 353-359, 2021 May.
Article in English | MEDLINE | ID: mdl-33502723

ABSTRACT

According to the World Health Organization, bacterium Acinetobacter baumannii is the first on the critical priority list of pathogens in urgent need for new antibiotics. The increasing resistance of A. baumannii to the last-line treatment options, including carbapenems, is a global problem. We report the molecular epidemiology of 12 carbapenem-resistant clinical isolates of A. baumannii collected from hospitalised patients in three neighbouring countries in Southeast Europe: Croatia, Serbia, and Bosnia and Herzegovina, giving an insight into the molecular characterisation and evolutionary history of the acquisition of resistance genes. Besides the blaOXA-23 gene, the endemic presence of OXA-72 oxacillinase of the same origin for more than a decade as the leading mechanism of carbapenem resistance in Southeast Europe was confirmed. To the best of our knowledge, this is the first paper that investigates and analyses the phylogenetic association of the most common mechanisms of resistance to carbapenems in clinical isolates of A. baumannii originating from three neighbouring countries in Southeast Europe.


Subject(s)
Acinetobacter baumannii , Bacterial Proteins/genetics , Drug Resistance, Bacterial/genetics , beta-Lactamases/genetics , Acinetobacter baumannii/enzymology , Acinetobacter baumannii/genetics , Anti-Bacterial Agents/pharmacology , Carbapenems/pharmacology , Europe , Humans , Microbial Sensitivity Tests , Phylogeny
11.
J Hazard Mater ; 404(Pt A): 124079, 2021 02 15.
Article in English | MEDLINE | ID: mdl-33017711

ABSTRACT

Bisphenol F (BPF) and bisphenol S (BPS) are becoming widespread in the environment despite the lack of information regarding their fate during wastewater treatment and in the environment. This study assessed the biodegradation kinetics of BPF and BPS during biological wastewater treatment with activated sludge using GC-MS/MS, and the identification of biotransformation products (BTPs) using LC-QTOF-MS. The results showed that BPF and BPS degrade readily and unlikely accumulate in biosolids or wastewater effluent (ci = 0.1 mg L-1, half-lives <4.3 days). The first-order kinetic model revealed that BPF (kt = 0.20-0.38) degraded faster than BPS (kt = 0.04-0.16) and that degradation rate decreases with an increasing initial concentration of BPS (half-lives 17.3 days). The absence of any additional organic carbon source significantly slowed down degradation, in particular, that of BPS (lag phase on day 18 instead of day 7). The machine-learning algorithm adopted as part of the non-targeted workflow identified three known BTPs and one novel BTP of BPF, and one known and ten new BTPs of BPS. The data from this study support possible new biodegradation pathways, namely sulphation, methylation, cleavage and the coupling of smaller bisphenol moieties.


Subject(s)
Sewage , Water Pollutants, Chemical , Benzhydryl Compounds/analysis , Biotransformation , Kinetics , Phenols , Tandem Mass Spectrometry , Water Pollutants, Chemical/analysis
12.
Environ Sci Pollut Res Int ; 28(3): 3445-3454, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32918687

ABSTRACT

Bisphenol A (BPA) is, due to its widespread use including the production of plastic materials, an ubiquitous pollutant in the aquatic environment. Due to evidence of adverse BPA effects on the environment and human health, its use has been restricted and replaced by analogues such as bisphenol F (BPF). This study examined the toxicity of BPA, BPF and their mixture towards primary producers, the eukaryotic green alga Pseudokirchneriella subcapitata and the prokaryotic cyanobacterium Synechococcus leopoliensis. The results demonstrated that S. leopoliensis is more sensitive than P. subcapitata, whereas toxic potential of the two BPs is comparable and represents comparable hazard for phytoplankton. The toxicity of the binary mixture was predicted by different models (concentration addition, independent action, combination index and the isobologram method) and compared to experimental data. Additive effect was observed in P. subcapitata over the whole effect concentration range (EC5-EC90), whereas in S. leopoliensis, no pronounced combined effect was observed. The environmental risk characterisation based on the comparison of reported concentrations of BPA and BPF in surface waters to the predicted no-effect concentration values obtained in this study showed that at certain industrial areas, BPA represents environmental risk, whereas BPF does not. However, BPF concentrations in aquatic environment are expected to increase in the future. To enable environmental risk assessment of BP analogues, more data on the toxicity to aquatic species, including combined effect, as well as data on their occurrence in the aquatic environment are needed.Graphical abstract.


Subject(s)
Environmental Pollutants , Synechococcus , Benzhydryl Compounds/toxicity , Humans , Phenols , Phytoplankton
13.
Microb Drug Resist ; 27(3): 383-390, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32721271

ABSTRACT

Increasingly difficult treatment of multidrug-resistant (MDR) bacteria has become a global problem of the 21st century. Within a group of multiresistant bacteria, the Acinetobacter baumannii convincingly occupies the position at the top of the group designated as ESKAPE pathogens. In this study, 61 isolates of A. baumannii were recovered from different samples originating from various departments of the University Clinical Hospital Mostar during 2018. All of the isolates were identified using conventional phenotypic methods and the VITEK® 2 Compact System, and were confirmed by MALDI-TOF mass spectrometry. The minimum inhibitory concentrations (MICs) were determined by the microbroth dilution method using MICRONAUT-S MDR MRGN-Screening and VITEK 2 Compact System. All strains were resistant to carbapenems and classified in eight different resistotypes according to their antibiotic resistance and macrorestriction pulsed-field gel electrophoresis profiles, with all belonging to IC II. One isolate displayed resistance to colistin (MIC ≥16 mg/L). The presence of blaOXA genes encoding OXA-type carbapenemases was investigated by multiplex PCR and the Eazyplex® SuperBugAcineto system and showed 100% compatibility with the detection of acquired oxacillinases. Molecular characterization of the isolates tested in this study revealed the OXA-23- and OXA-40-like groups of acquired oxacillinases. Sequencing of two PCR products of the OXA-40-like group confirmed the presence of OXA-72. Survival assays with two selected isolates of A. baumannii encoding different mechanisms of carbapenem resistance revealed that one isolate was able to survive on a fragment of white laboratory coat during 90 days of monitoring. To the best of our knowledge, this is the first article to present the results of a comprehensive phenotypic, genotypic, and molecular analysis of A. baumannii isolates from the leading clinical hospital center in the southwestern part of Bosnia and Herzegovina, including data for the survival of this pathogen on the white laboratory coats used as compulsory medical clothing.


Subject(s)
Acinetobacter baumannii/genetics , Anti-Bacterial Agents/pharmacology , Carbapenems/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Bosnia and Herzegovina/epidemiology , Cross Infection , Electrophoresis, Gel, Pulsed-Field , Genes, Bacterial , Hospitals, University , Humans , Microbial Sensitivity Tests
14.
Food Chem ; 331: 127326, 2020 Nov 30.
Article in English | MEDLINE | ID: mdl-32674069

ABSTRACT

A precise and accurate GC-MS/MS method with ng L-1 LLOQs, acceptable recovery (78-107%) and estimated uncertainty (U > 20%, except at LLOQ) was developed following the Eurachem guidelines. We established the migration and stability of twelve bisphenols in two food simulants (C: 20% ethanol, and B: 3% acetic acid) from beverage cans (n = 16) and reusable metal and plastic sports bottles (n = 51). Bisphenols were stable in dried (eight weeks, -20 °C) and derivatised extracts (seven days, 21 °C). Cans leached BPA (<5865 ng L-1), three BPF isomers (8.2-1286 ng L-1) and BPAP (1.6 ng L-1), while bottles leached BPA (<222 ng L-1) and BPF, BPE, BPB and BPZ (1.1-4.6 ng L-1). Simulant C was more aggressive than simulant B, and concentrations of bisphenols decreased with consecutive exposure to simulants. Levels of BPA migrating from cans did not exceed the specific migration limits.


Subject(s)
Benzhydryl Compounds/chemistry , Beverages/analysis , Equipment Reuse , Food Packaging , Phenols/chemistry , Sports , Food Contamination/analysis
15.
Sci Total Environ ; 743: 140724, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32653716

ABSTRACT

The rapid growth in the variety and quantity of contaminants of emerging concern (CEC) in wastewater indicates the necessity for developing efficient and environmentally friendly methods for their removal. This study investigates the removal efficiency of 46 CEC, including 12 bisphenols, from wastewater using a lab and pilot-scale hydrodynamic cavitation generator alone and in combination with UV illumination (pilot-scale). During lab-scale cavitation, the highest removal efficiencies of bisphenols (15-63%) for this specific design of cavitator were obtained at a rotational frequency (vcav) = 9500 rpm and time (tcav) = 10 min. Temperature and the physicochemical properties (e.g. Kow) of the studied compounds also had a significant effect on removal efficiency. At the pilot-scale, 11 CECs were quantifiable in the wastewater influent, and the generator operated at νcav = 2290 and 2700 rpm. The highest removal efficiencies (15-90%) were obtained at a lower νcav = 2290 rpm while neither an increase in νcav, tcav or the presence of UV-C light increased the removal efficiency. A lower νcav also reduced the hydrodynamic power of the cavitator from 477 W to 377 W, resulting in reduced energy consumption. Overall, the results show the potential of hydrodynamic cavitation for a large-scale application as a pre-treatment technology and pave the way for future improvements in the design of cavitation reactors.

16.
Water Res ; 181: 115864, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32480056

ABSTRACT

Sertraline is one of the most commonly prescribed antidepressants in the last few years. Therefore, it is not surprising that it is regularly detected in wastewaters, surface waters, sediments, biosolids and biota. Effluents from wastewater treatment plants are the main contributors to its presence in the environment. The presented study aims to elucidate the processes involved in its removal, concentrating mainly on sorption and biodegradation during wastewater treatment. We performed our laboratory scale experiments in two sets of experiments: 1) batch biodegradation and sorption experiments and 2) flow-through laboratory scale pilot wastewater treatment bioreactors. The batch experiments revealed that sorption to activated sludge was the leading removal process, eliminating up to 90% of sertraline present in the batches. Biodegradation was however the secondary removal process, influenced by the presence of alternative easily biodegradable carbon sources. We postulated chemical structures of ten detected biotransformation products. Among these, we propose the previously recognized metabolite norsertraline, sertraline ketone and hydroxy-sertraline. All the remaining biotransformation products are herein reported for the first time. The removal efficiency of approximately 94% was determined after the treatment in the flow-through bioreactors. To support our findings, we sampled influents and effluents from two wastewater treatment plants and untreated wastewater from a psychiatric hospital. Removal efficiencies of 81% and 77% were determined, and along with the parent compound sertraline, the presence of eight transformation products was confirmed in the actual wastewaters.


Subject(s)
Wastewater , Water Pollutants, Chemical , Antidepressive Agents , Biodegradation, Environmental , Biotransformation , Sertraline , Sewage , Waste Disposal, Fluid
17.
Environ Res ; 179(Pt A): 108738, 2019 12.
Article in English | MEDLINE | ID: mdl-31542492

ABSTRACT

The limited knowledge on the stability, removal, and the fate of bisphenol A analogues in the aqueous environment led us to assess the removal by hydrolysis, adsorption, biological treatment and UV photolysis of eighteen common bisphenol compounds (BPs). Hydrolysis of BPs does not occur. The main factor affecting their stability in wastewater samples is storage time, and safe storage conditions were found to be -20 °C or 4 °C for up to four weeks. The results also revealed no significant reduction in the levels of BPs standards when stored in either methanol or ultrapure water. BPE was found to be the most stable, followed by BPF isomers, BPS and BPF, while BP26DM was the least stable and BPM, BPPH, BPP, BPBP and BPFL were quickly adsorbed. For most BPs, the removal efficiency of biological treatment was >85%, and there was no difference between the suspended activated sludge and moving bed bioreactors. Different adsorption affinities of the BPs to biomass were observed and reflect the differences in their Kow. In terms of degradability, direct UV photolysis in water produced three groups of BPs: (A) highly removable (RE > 94%), (B) moderately removable (RE 50-80%) and (C) poorly removable (RE 25-45%). In nearly all cases degradation followed pseudo-first-order kinetics.


Subject(s)
Environmental Pollutants/chemistry , Phenols/chemistry , Photochemical Processes , Benzhydryl Compounds , Photolysis , Ultraviolet Rays
18.
Sci Total Environ ; 664: 595-604, 2019 May 10.
Article in English | MEDLINE | ID: mdl-30763840

ABSTRACT

Bisphenols (BPs) are industrial chemicals that are used as monomers in the production of polycarbonate plastics and epoxy resins. These compounds can leach into the aqueous environment, where they can potentially have toxic effects. The aim of this study was to assess the photochemical degradation of three common bisphenols: BPF, BPS and BPZ in aqueous solution and determine their degradation kinetics and characterise their transformation products. Three independent experiments were performed based on: 1) direct photolysis using UV irradiation, 2) cyclodextrin-enhanced photolysis and 3) the photo-Fenton reaction. Analysis was performed using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled to high-resolution quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS). This approach enabled for the first time a comparison between various conditions of photochemical degradation, revealing to be an effective way of removing (>90%) BPF, BPS and BPZ from aqueous samples. In all cases, degradation followed a pseudo-first order kinetic profile, while removal efficiency and formation of transformation products depended on the applied process. The photo-Fenton process resulted in the shortest half-lives (16.1 ̶ 21.7 min) and generated the highest number of transformation products. Overall, in this study we identified 11 novels and eight previously reported TPs.

19.
Toxicol Lett ; 295: 115-123, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29908846

ABSTRACT

Bisphenol S (BPS) is increasingly used as substitute for bisphenol A, resulting in higher potential of human exposure to this compound. Yet, information on the human metabolism of BPS is limited. Hence, current biomonitoring studies rely only on the measurement of BPS itself, leading to a potential underestimation of assessing human exposure to this emerging contaminant. The aims of this study were to investigate the in vitro metabolic pathways of BPS using human liver microsomes and cytosol fractions and propose in vitro metabolites for evaluation in pharmacokinetics studies. Liquid chromatography coupled to quadrupole time-of-flight high-resolution mass spectrometry was used for the screening, identification, and structural elucidation of Phase I and II metabolites of BPS for the first time. Metabolite identification was performed using two complementary workflows: suspect and untargeted screening. Two Phase I metabolites were formed through hydroxylation of the phenolic rings. Four Phase II metabolites were formed through conjugation with glucuronic acid or sulfate. Three of these metabolites, namely dihydroxy-BPS, hydroxy-BPS-glucuronide and hydroxy-BPS-sulfate were identified and structurally elucidated for the first time. As such, we provide an expanded set of in vitro biotransformation products of BPS, which can potentially support a reliable assessment of BPS exposure in future biomonitoring studies.


Subject(s)
Environmental Pollutants/metabolism , Liver/metabolism , Phenols/metabolism , Sulfones/metabolism , Chromatography, Liquid , Environmental Pollutants/pharmacokinetics , Environmental Pollutants/toxicity , Glucuronides/metabolism , Humans , Hydroxylation , Liver/enzymology , Metabolic Detoxication, Phase I , Metabolic Detoxication, Phase II , Microsomes, Liver/metabolism , Phenols/pharmacokinetics , Phenols/toxicity , Risk Assessment , Sulfates/metabolism , Sulfones/pharmacokinetics , Sulfones/toxicity , Tandem Mass Spectrometry , Workflow
20.
Sci Total Environ ; 616-617: 744-752, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29096955

ABSTRACT

This study reports the occurrence of eight bisphenols (BPs): bisphenol AF (BPAF), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bisphenol F (BPF), bisphenol S (BPS) and bisphenol Z (BPZ) in wastewaters (WWs). Sample preparation involved pre-concentration with SPE cartridges (Oasis HLB), followed by derivatization using N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide with 1% tert-butyldimethylchlorosilane. Chemical analysis was based on gas chromatography-mass spectrometry. A validated method with limits of detection (LODs) at ngL-1 range was applied to WWs collected at five Slovene wastewater treatment plants (WWTPs) and WW inflows from industrial, commercial and residential sources entering the sewerage systems of two catchments (Domzale-Kamnik (DK) and Ljubljana (LJ)). The presence of all BPs was confirmed in three inflows in DK and two inflows in the LJ catchments. High cumulative concentrations of all BPs were determined in WW from food processing facilities (LJ: 3030ngL-1 and DK: 599ngL-1). A high detection frequency was observed in the WW from two textile cleaning companies (6 BPs for LJ and 8 BPs for DK). The analysis of WW from WWTPs revealed that only BPF (36.7ngL-1) and BPS (40.6ngL-1) were >LODs in the influents, whereas other BPs were detected also in the effluents. BPZ was found in the highest concentration (403ngL-1 at WWTP-DK). WW collected at this WWTP also contained the highest amount of BPE (238ngL-1). Although BPs removal could not be directly compared between the WWTPs, with the exception of BPAP and BPB in the case of two smaller WWTPs (6.39%-43.2%) bisphenols were in general highly removed (≥96.2%). Finally, levels of BPC>LOD are reported for first time (WWTP in the DK catchment: 1.01ngL-1-11.8ngL-1; LJ inflow from food processing plant up to 2560ngL-1).

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