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1.
J Appl Toxicol ; 42(7): 1121-1136, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34964157

RESUMEN

In comparison with analytical tools, bioassays provide higher sensitivity and more complex evaluation of environmental samples and are indispensable tools for monitoring increasing in anthropogenic pollution. Nevertheless, the disadvantage in cellular assays stems from the material variability used within the assays, and an interlaboratory adaptation does not usually lead to satisfactory test sensitivities. The aim of this study was to evaluate the influence of material variability on CXCL12 secretion by T47D cells, the outcome of the CXCL-test (estrogenic activity assay). For this purpose, the cell line sources, sera suppliers, experimental and seeding media, and the amount of cell/well were tested. The multivariable linear model (MLM), employed as an innovative approach in this field for parameter evaluation, identified that all the tested parameters had significant effects. Knowledge of the contributions of each parameter has permitted step-by-step optimization. The most beneficial approach was seeding 20,000 cells/well directly in treatment medium and using DMEM for the treatment. Great differences in both basal and maximal cytokine secretions among the three tested cell lines and different impacts of each serum were also observed. Altogether, both these biologically based and highly variable inputs were additionally assessed by MLM and a subsequent two-step evaluation, which revealed a lower variability and satisfactory reproducibility of the test. This analysis showed that not only parameter and procedure optimization but also the evaluation methodology must be considered from the perspective of interlaboratory method adaptation. This overall methodology could be applied to all bioanalytical methods for fast multiparameter and accurate analysis.


Asunto(s)
Estrógenos , Contaminantes Químicos del Agua , Bioensayo , Línea Celular , Monitoreo del Ambiente/métodos , Estrógenos/toxicidad , Estrona , Modelos Lineales , Reproducibilidad de los Resultados
3.
Toxicon ; 195: 69-77, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33711366

RESUMEN

Secondary metabolites of cyanobacteria and algae released during algal blooms often exhibit toxic effects, but only a small number of the metabolites are the subject of routine analytical screenings. Alternatively, ecotoxicological assays offer a better representation of the overall negative effects. The aim of this work was to compare multiple assays in their sensitivity towards cellular algal organic matter (COM) of the toxin-producing cyanobacterium Microcystis aeruginosa. Multiple endpoints were investigated: mortality, growth inhibition, bioluminescence inhibition, genotoxicity, endocrine-disrupting effects, oxidative stress, and the induction of ethoxyresorufin-O-deethylase (EROD). Three rainbow trout (Oncorhynchus mykiss) cell lines as well as representatives of bacteria, yeasts, algae, vascular plants, and crustaceans were employed, and the results were expressed per mg of dissolved organic carbon (DOC) in the COM. M. aeruginosa COM was toxic to the RTgill-W1, RTG-2, and RTL-W1 cell lines (EC50 values ranging from 0.48 ± 0.02 to 1.9 ± 0.1 mgDOC/L), to the crustacean Thamnocephalus platyurus (LC50 = 20 ± 1 mgDOC/L), and to Lepidium sativum (IC50 = 241 ± 13 mgDOC/L). In contrast, no effect was observed for bacteria and yeasts, and the growth of the alga Desmodesmus subspicatus was even stimulated. No genotoxicity, endocrine-disrupting effects or increase in oxidative stress or EROD activity was detected. The content of six microcystins (MC-LR, MC-RR, MC-YR, MC-LY, MC-LW, and MC-LF), anatoxin-a, cylindrospermopsin, and nodularin in the M. aeruginosa COM was determined by liquid chromatography-tandem mass spectrometry. An artificially prepared mixture of the detected cyanotoxins in the corresponding concentrations did not induce response in the O. mykiss cell lines and T. platyurus, suggesting that other cyanobacterial metabolites are responsible for the toxicity of M. aeruginosa.


Asunto(s)
Cianobacterias , Microcystis , Eutrofización , Microcistinas/toxicidad
4.
Environ Sci Pollut Res Int ; 28(24): 31566-31574, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33606164

RESUMEN

Biologically active micropollutants that contain diverse phenolic/aromatic structures are regularly present in wastewater effluents and are even found in drinking water. Advanced green technologies utilizing immobilized laccase and/or peroxidase, which target these micropollutants directly, may provide a reasonable alternative to standard treatments. Nevertheless, the use of these enzymes is associated with several issues that may prevent their application, such as the low activity of laccase at neutral and basic pH or the necessity of hydrogen peroxide addition as a co-substrate for peroxidases. In this study, the activity of laccase from Trametes versicolor and horseradish peroxidase was evaluated across a range of commonly used substrates (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), syringaldazine, and guaiacol). Moreover, conditions for their optimal performance were explored along with an assessment of whether these conditions accurately reflect the effectivity of both enzymes in the degradation of a mixture of bisphenol A, 17α-ethinylestradiol, triclosan, and diclofenac in tap drinking water and secondary wastewater effluent. Laccase and horseradish peroxidase showed optimal activity at strongly acidic pH if ABTS was used as a substrate. Correspondingly, the activities of both enzymes detected using ABTS in real waters were significantly enhanced by adding approximately 2.5% (v/v) of McIlvaine's buffer. Degradation of a mixture of micropollutants in wastewater with 2.5% McIlvaine's buffer (pH 7) resulted in a substantial decrease in estrogenic activity. Low degradation efficiency of micropollutants by laccase was observed in pure McIlvaine's buffer of pH 3 and 7, compared with efficient degradation in tap water of pH 7.5 without buffer. This study clearly shows that enzyme activity needs to be evaluated on micropollutants in real waters as the assessment of optimal conditions based on commonly used substrates in pure buffer or deionized water can be misleading.


Asunto(s)
Agua Potable , Lacasa , Peroxidasa de Rábano Silvestre , Polyporaceae , Trametes , Aguas Residuales
5.
Chemosphere ; 265: 129082, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309446

RESUMEN

Sewage sludge was excluded from the list of component materials for the production of EU fertilizing products and it was banned as feedstock to produce pyrolysis & gasification materials in European Commission's technical proposals for selected new fertilizing materials under the Regulation 2019/1009 (STRUBIAS report). This exclusion of pyrolysis as a viable way to treat sewage sludge was mainly due to the lack of data on the fate of organic pollutants at pyrolysis conditions. In this work, we are addressing this knowledge gap. We studied slow pyrolysis as a potential process to efficiently treat organic pollutants present in stabilized sewage sludge. Sewage sludge was pyrolyzed in a quartz fixed bed reactor at temperatures of 400-800 °C for 2 h and the sludge and resulting sludge-chars were analyzed for the presence of four groups of organic pollutants, namely (i) polychlorinated biphenyls (PCBs), (ii) polycyclic aromatic hydrocarbons (PAHs), (iii) pharmaceuticals, and (iv) endocrine-disrupting and hormonal compounds. Pyrolysis at ≥ 400 °C effectively removed pharmaceuticals (group iii) to below detection limits, whereas pyrolysis at temperatures higher than 600 °C was required to remove more than 99.8% of the compounds from groups i, ii and iv. Based on these findings, we propose, that high temperature (>600 °C) slow pyrolysis can satisfactory remove organic pollutants from the resulting sludge-char, which could be safely applied as soil improver.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/análisis , Pirólisis , Aguas del Alcantarillado , Temperatura
6.
Molecules ; 25(2)2020 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-31963668

RESUMEN

Chlorhexidine (CHX) and octenidine (OCT), antimicrobial compounds used in oral care products (toothpastes and mouthwashes), were recently revealed to interfere with human sex hormone receptor pathways. Experiments employing model organisms-white-rot fungi Irpex lacteus and Pleurotus ostreatus-were carried out in order to investigate the biodegradability of these endocrine-disrupting compounds and the capability of the fungi and their extracellular enzyme apparatuses to biodegrade CHX and OCT. Up to 70% ± 6% of CHX was eliminated in comparison with a heat-killed control after 21 days of in vivo incubation. An additional in vitro experiment confirmed manganese-dependent peroxidase and laccase are partially responsible for the removal of CHX. Up to 48% ± 7% of OCT was removed in the same in vivo experiment, but the strong sorption of OCT on fungal biomass prevented a clear evaluation of the involvement of the fungi or extracellular enzymes. On the other hand, metabolites indicating the enzymatic transformation of both CHX and OCT were detected and their chemical structures were proposed by means of liquid chromatography-mass spectrometry. Complete biodegradation by the ligninolytic fungi was not achieved for any of the studied analytes, which emphasizes their recalcitrant character with low possibility to be removed from the environment.


Asunto(s)
Antiinfecciosos Locales/metabolismo , Biodegradación Ambiental , Clorhexidina/metabolismo , Hongos/metabolismo , Piridinas/metabolismo , Clorhexidina/química , Atención Odontológica , Humanos , Iminas , Metabolómica/métodos , Piridinas/química , Transformación Genética
7.
Chemosphere ; 217: 534-541, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30445398

RESUMEN

Personal care product consumption has increased in the last decades. A typical representative ingredient, i.e., triclosan, was identified in the scientific literature as an endocrine disruptor, and its use is restricted in several applications. Oral hygiene formulations contain various compounds, including synthetic phenol derivatives, quaternary ammonium compounds (QACs), various amides and amines, or natural essential oils containing terpenes. The aim of this paper was to explore possible endocrine-disrupting effects of these most-used compounds. For this purpose, two different assays based on recombinant yeast (BMAEREluc/ERα; BMAEREluc/AR) and human cell lines (T47D; AIZ-AR) were employed to investigate the agonistic and antagonistic properties of these compounds on human estrogen and androgen receptors. The results showed that none of the compounds were indicated as agonists of the steroid receptors. However, octenidine (OCT, QAC-like) and hexadecylpyridinium (HDP, QAC) were able to completely inhibit both androgenic (IC50 OCT = 0.84 µM; IC50 HDP = 1.66 µM) and estrogenic (IC50 OCT = 0.50 µM; IC50 HDP = 1.64 µM) signaling pathways in a dose-dependent manner. Additionally, chlorhexidine was found to inhibit the 17ß-estradiol response, with a similar IC50 (2.9 µM). In contrast, the natural terpenes thymol and menthol were found to be competitive antagonists of the receptors; however, their IC50 values were higher (by orders of magnitude). We tried to estimate the risk associated with the presence of these compounds in environmental matrices by calculating hazard quotients (HQs), and the calculated HQs were found to be close to or greater than 1 only when predicted environmental concentrations were used for surface waters.


Asunto(s)
Antibacterianos/uso terapéutico , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Antibacterianos/farmacología , Humanos
8.
N Biotechnol ; 43: 53-61, 2018 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-28502780

RESUMEN

The white rot fungus Pleurotus ostreatus HK 35, which is also an edible industrial mushroom commonly cultivated in farms, was tested in the degradation of typical representatives of endocrine disrupters (EDCs; bisphenol A, estrone, 17ß-estradiol, estriol, 17α-ethinylestradiol, triclosan and 4-n-nonylphenol); its degradation efficiency under model laboratory conditions was greater than 90% within 12 days and better than that of another published strain P. ostreatus 3004. A spent mushroom substrate from a local farm was tested for its applicability in various batch and trickle-bed reactors in degrading EDCs in model fortified and real communal wastewater. The reactors were tested under various regimes including a pilot-scale trickle-bed reactor, which was finally tested at a wastewater treatment plant. The result revealed that the spent substrate is an efficient biodegradation agent, where the fungus was usually able to remove about 95% of EDCs together with suppression of the estrogenic activity of the sample. The results showed the fungus was able to operate in the presence of bacterial microflora in wastewater without any substantial negative effects on the degradation abilities. Finally, a pilot-scale trickle-bed reactor was installed in a wastewater treatment plant and successfully operated for 10days, where the bioreactor was able to remove more than 76% of EDCs present in the wastewater.


Asunto(s)
Reactores Biológicos/microbiología , Disruptores Endocrinos/metabolismo , Pleurotus/metabolismo , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Disruptores Endocrinos/análisis , Disruptores Endocrinos/aislamiento & purificación , Contaminantes Químicos del Agua/análisis
9.
Sci Total Environ ; 607-608: 1451-1465, 2017 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-28763941

RESUMEN

The present study describes a pilot remediation test of a co-mingled plume containing BTEX, chlorinated pollutants and pharmaceuticals. Remediation was attempted using a combination of various approaches, including a pump and treat system applying an advanced oxidation process and targeted direct push injections of calcium peroxide. The remediation process was monitored intensively and extensively throughout the pilot test using various conventional and passive sampling methods, including next-generation amplicon sequencing. The results showed that the injection of oxygen-saturated treated water with residual hydrogen peroxide and elevated temperature enhanced the in situ removal of monoaromatics and chlorinated pollutants. In particular, in combination with the injection of calcium peroxide, the conditions facilitated the in situ bacterial biodegradation of the pollutants. The mean groundwater concentration of benzene decreased from 1349µg·L-1 prior to the test to 3µg·L-1 within 3months after the calcium peroxide injections; additionally, monochlorobenzene decreased from 1545µg·L-1 to 36µg·L-1, and toluene decreased from 143µg·L-1 to 2µg·L-1. Furthermore, significant degradation of the contaminants bound to the soil matrix in less permeable zones was observed. Based on a developed 3D model, 90% of toluene and 88% of chlorobenzene bound to the soil were removed during the pilot test, and benzene was removed almost completely. On the other hand, the psychopharmaceuticals were effectively removed by the employed advanced oxidation process only from the treated water, and their concentration in groundwater remained stagnant due to inflow from the surroundings and their absence of in situ degradation. The employment of passive sampling techniques, including passive diffusion bags (PDB) for volatile organic pollutants and their respective transformation products, polar organic compound integrative samplers (POCIS) for the pharmaceuticals and in situ soil microcosms for microbial community analysis, was proven to be suitable for monitoring remediation in saturated zones.

10.
Water Res ; 120: 245-255, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28500989

RESUMEN

This study was performed to test the feasibility of several decontamination methods for remediating heavily contaminated groundwater in a real contaminated locality in the Czech Republic, where a pharmaceuticals plant has been in operation for more than 80 years. The site is polluted mainly by recalcitrant psychopharmaceuticals and monoaromatic hydrocarbons, such as benzene, toluene and chlorobenzene. For this purpose, an advanced oxidation technique employing UV radiation with hydrogen peroxide dosing was employed, in combination with simple aeration pretreatment. The results showed that UV/H2O2 was an efficient and necessary step for degradation of the pharmaceuticals; however, the monoaromatics were already removed during the aeration step. Characterization of the removal mechanisms participating in the aeration revealed that volatilization, co-precipitation and biodegradation contributed to the process. These findings were supported by bacterial metabolite analyses, phospholipid fatty acid analysis, qPCR of representatives of the degradative genes and detailed characterization of the formed precipitate using Mössbauer spectroscopy and scanning electron microscopy. Further tests were carried out in a continuous arrangement directly connected to the wells already present in the locality. The results documented the feasibility of combination of the photo-reactor employing UV/H2O2 together with aeration pretreatment for 4 months, where the overall decontamination efficiency ranged from 72% to 99% of the pharmaceuticals. We recorded even better results for the monoaromatics decontamination except for one month, when we encountered some technical problems with the aeration pump. This demonstrated the necessity of using the aeration step.


Asunto(s)
Contaminación Ambiental/prevención & control , Agua Subterránea , Contaminantes Químicos del Agua , Benceno , Biodegradación Ambiental , Clorobencenos , República Checa , Peróxido de Hidrógeno , Preparaciones Farmacéuticas , Tolueno
11.
J Chromatogr A ; 1440: 15-22, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26924752

RESUMEN

A rapid and reliable analytical method was developed for the quantitative determination of psychopharmaceuticals, their precursors and by-products in real contaminated samples from a pharmaceutical company in Olomouc (Czech Republic), based on SPE disk extraction and detection by ultra performance liquid chromatography, combined with time-of-flight mass spectrometry. The target compounds were quantified in the real whole-water samples (water including suspended particles), both in the presence of suspended particulate matter (SPM) and high concentrations of other organic pollutants. A total of nine compounds were analyzed which consisted of three commonly used antidepressants (tricyclic antidepressants and antipsychotics), one antitussive agent and five by-products or precursors. At first, the SPE disk method was developed for the extraction of water samples (dissolved analytes, recovery 84-104%) and pressurised liquid extraction technique was verified for solid matrices (sludge samples, recovery 81-95%). In order to evaluate the SPE disk technique for whole water samples containing SPM, non contaminated groundwater samples were also loaded with different amounts (100 and 300mgL(-1)) of real contaminated sludge originating from the same locality. The recoveries from the whole-water samples obtained by SPE disk method ranged between 67 and 119% after the addition of the most contaminated sludge. The final method was applied to several real groundwater (whole-water) samples from the industrial area and high concentrations (up to 10(3)µgL(-1)) of the target compounds were detected. The results of this study document and indicate the feasibility of the SPE disk method for analysis of groundwater.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua Subterránea/química , Espectrometría de Masas , Material Particulado/análisis , Psicotrópicos/análisis , Extracción en Fase Sólida , Aguas Residuales/química , Cromatografía Líquida de Alta Presión , República Checa , Monitoreo del Ambiente/instrumentación , Contaminantes Químicos del Agua/análisis
12.
Crit Care ; 16(6): R231, 2012 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-23232151

RESUMEN

INTRODUCTION: Several observational studies suggest that statins modulate the pathophysiology of sepsis and may prevent its progression. The aim of this study was to determine if the acute administration of atorvastatin reduces sepsis progression in statin naïve patients hospitalized with sepsis. METHODS: A single centre phase II randomized double-blind placebo-controlled trial. Patients with sepsis were randomized to atorvastatin 40 mg daily or placebo for the duration of their hospital stay up to a maximum of 28-days. The primary end-point was the rate of sepsis progressing to severe sepsis during hospitalization. RESULTS: 100 patients were randomized, 49 to the treatment with atorvastatin and 51 to placebo. Patients in the atorvastatin group had a significantly lower conversion rate to severe sepsis compared to placebo (4% vs. 24% p = 0.007.), with a number needed to treat of 5. No significant difference in length of hospital stay, critical care unit admissions, 28-day and 12-month readmissions or mortality was observed. Plasma cholesterol and albumin creatinine ratios were significantly lower at day 4 in the atorvastatin group (p < 0.0001 and p = 0.049 respectively). No difference in adverse events between the two groups was observed (p = 0.238). CONCLUSIONS: Acute administration of atorvastatin in patients with sepsis may prevent sepsis progression. Further multi-centre trials are required to verify these findings. TRIAL REGISTRATION: International Standard Randomized Control Trial Registry ISRCTN64637517.


Asunto(s)
Antiinflamatorios/uso terapéutico , Ácidos Heptanoicos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pirroles/uso terapéutico , Sepsis/tratamiento farmacológico , Antiinflamatorios/administración & dosificación , Atorvastatina , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Ácidos Heptanoicos/administración & dosificación , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Pirroles/administración & dosificación , Sepsis/mortalidad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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