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1.
Environ Sci Pollut Res Int ; 30(47): 104633-104639, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37707725

RESUMEN

The identification of the degradation products in objects of cultural significance, including musical instruments (e.g., a piano), is a key issue for the preservation and valorisation processes of cultural heritage. The aim of this study is to characterize the degradation products of lead weights from an important Steinway & sons piano using a multi-analytical approach that includes ionic chromatography (IC), X-ray diffraction (XRD) and Fourier transform-infrared (FTIR) spectroscopy analyses. These techniques allowed us to identify hydrocerussite as the main degradation product on the superficial layer of lead weights, followed by lead acetate and formate. Moreover, accelerated corrosion experiments in closed environments were performed under acetic and formic acid atmospheres to evaluate the development of lead acetate and formate over time. Exposure of lead weights to formic and acetic acid vapours leads to the prevalent formation of basic lead formate, which promotes the formation of hydrocerussite. These results can help to limit the degradation of these piano components and consequently preserve the sound of the piano itself.


Asunto(s)
Plomo , Núcleo Familiar , Ácido Acético , Formiatos
2.
Anal Bioanal Chem ; 415(20): 5003-5010, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37314484

RESUMEN

Cu2+ are ubiquitous ions in the ecosystem and are responsible of serious environmental pollution. Indeed, the development of sensitive methods for Cu2+ detection is an urgent demand. In this work, we proposed a new spectrophotometric method for Cu2+ determination in different water matrices (distilled water, drinking water, wastewater, and river water). The method employs a bio-based organic ligand namely tetrasodium iminodisuccinate (IDS) able to form a stable complex with the analyte with a maximum absorption at 710 nm. Within the linear range of 6.3-381 mg L-1, the limit of detection (LOD) was determined to be as 1.43 mg L-1. Moreover, the recovery data of the spiked analysis of drinking/river/wastewater water samples were also satisfactory and verified the feasibility of the method for the analysis of Cu2+ in natural conditions. Finally, the AGREE assessment tool was used for a quantitative evaluation of the proposed method and reference method, in agreement with the green analytical chemistry principles. The results showed the lower environmental impact of the proposed method and the suitability of this novel approach for Cu2+ in water matrices.

3.
J Environ Manage ; 340: 117950, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37094386

RESUMEN

Landfill leachate (LL) represents a very complex effluent difficult to treat and to manage which usually requires a chemical pre-treatment. In this study, response surface methodology (RSM) was used to identify the optimum operating conditions of the Fenton process as a pre-treatment of LL in order to reduce the high organic content and simultaneously optimize the BOD5:TN:TP ratio. The dosages of Fenton process reagents, namely Fe2+ and H2O2, were used as variables for the implementation of RSM. Chemical oxygen demand (COD), five-days biochemical oxygen demand (BOD5), total nitrogen (TN), total phosphorus (TP) removals (and simultaneously BOD5:TN:TP ratio), sludge-to-iron ratio (SIR) and organic removal-to-sludge ratio (ORSR) were selected as target responses. This approach considered the SIR and ORSR parameters which are a useful tool for assessing sludge formation during the process along with organic matter removal. The variables (H2O2 and Fe2+ concentrations) significantly affected the responses, as the role of oxidation mechanism is dominant with respect to coagulation one. The pH for the process was fixed to 2.8 while the treatment time was set to 2 h. The optimum operational conditions obtained by perturbation and 3D surface plot, were found to be 4262 mg/L and 5104 mg/L for Fe2+ and H2O2, respectively (H2O2/Fe2+ molar ratio = 2) with COD, BOD5, TN and TP removals of 70%, 67%, 84% and 96% respectively, while SIR and ORSR final values were 1.15 L/mol and 33.79 g/L respectively, in accordance with models-predicted values. Moreover, the initial unbalanced BOD5:TN:TP ratio (9:1:1) was significantly improved (100:6:1), making the effluent suitable for a subsequent biological treatment. The investigated approach allowed to optimize the removal of organic load and nutrients as well as to minimize the sludge formation in Fenton process, providing a useful tool for the operation and management of LL pre-treatment.


Asunto(s)
Aguas del Alcantarillado , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Peróxido de Hidrógeno/química , Hierro/química , Oxidación-Reducción
4.
J Hazard Mater ; 452: 131235, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36948125

RESUMEN

In this work, Fe3+-iminodisuccinic acid (Fe:IDS) based solar photo Fenton (SPF), an Italian patented method, was investigated in quaternary treatment of real urban wastewater and compared to Fe3+-ethylenediamine-N,N'-disuccinic acid (Fe:EDDS) for the first time. Three pharmaceuticals (PCs) (sulfamethoxazole, carbamazepine and trimethoprim) and four pathogens (Escherichia coli, somatic and F-plus coliphages, Clostridium perfringens, consistently with the new EU regulation for wastewater reuse (2020/741)), were chosen as target pollutants. SPF with Fe:EDDS was more effective in PCs removal (80%, 10 kJ L-1) than the SPF with Fe:IDS (58%), possibly due to the higher capability of generating hydroxyl radicals. On the contrary, Fe:IDS was more effective (4.3 log inactivation for E. coli) than Fe:EDDS (1.9 log) in pathogens inactivation, possibly due to a lower iron precipitation and turbidity which finally promoted an improved intracellular photo-Fenton mechanism. Fe:L based SPF was subsequently coupled to sunlight/H2O2. Interestingly, while its combination with Fe:EDDS based SPF slightly increased disinfectant efficacy (2.3 vs 1.9 log inactivation for E. coli), the combination with Fe:IDS decreased inactivation efficiency (3.4 vs 4.3 log reduction). In conclusion, due to the good compromise between PCs removal and disinfection efficiency, Fe:IDS SPF alone is an attractive option for quaternary treatment for urban wastewater reuse.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Luz Solar , Peróxido de Hidrógeno , Escherichia coli , Quelantes , Preparaciones Farmacéuticas , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
5.
Molecules ; 28(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36838603

RESUMEN

In the present work, the microclimatic conditions (temperature (T), relative humidity (RH), and illuminance (I)), together with the air quality (both aerosol particulate matter (PM) and gaseous pollutants), were monitored to evaluate the environmental conditions inside the Santuario della Beata Vergine dei Miracoli in Saronno (VA), a masterpiece of the Italian Renaissance. For this purpose, dataloggers were used to carry out the T, RH, and I measurements, whereas an optical particle counter (OPC) was employed to perform the particle count and determine the concentration of the aerosol PM. Finally, diffusive passive samplers were used to determine the concentration of nitrogen dioxide (NO2) and BTEX (benzene, toluene, ethylbenzene, and xylenes). To identify possible spatial variations, the studies were conducted at different sites and different heights in the Sanctuary. Particular focus was given to the Easter week during which liturgical services attracting large numbers of people were carried out. Additionally, a comparison with the outdoor values was performed to highlight the accumulation phenomena and other variations in the concentrations of the species. Despite the indoor concentrations of pollutants and variations in the thermohygrometric parameters being generally lower compared to the outdoors (e.g., 5.2-15.0 µg m-3 versus 17.7-45.3 µg m-3 for NO2), the microclimatic conditions were often not in line with the Italian legislation and technical standards.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Contaminantes Ambientales , Humanos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Dióxido de Nitrógeno , Monitoreo del Ambiente , Contaminación del Aire/análisis , Material Particulado/análisis
6.
Environ Sci Pollut Res Int ; 30(2): 3112-3120, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35945319

RESUMEN

Thermo-mineral springs are widely spread over the volcanic areas of Salerno, a city in southern Italy. Although the water of thermal structures provides beneficial effects on human health, the air is characterized by the presence of potentially toxic compounds, such as hydrogen sulphide (H2S) and sulphur dioxide (SO2). Exposure to sulphurous compounds may have detrimental effects on human health, with asthma being the most common. In this study, air concentrations of H2S and SO2 in the thermal springs of Contursi Terme (Salerno, Italy) were monitored for 4 months (using both active and passive sampling), along with the chemical and microclimatic characterization of thermal water, to assess workers' exposure to these pollutants. An in-depth characterization of indoor air at the springs is paramount to establish emission control limits for occupational exposure and to take protective measures. The air concentration of SO2 varied from 0.11 ± 0.02 to 0.91 ± 0.02 mg/m3, following a seasonal pattern (higher values in winter and lower in spring). Conversely, indoor H2S concentrations did not vary significantly with time, but outdoor levels (from 0.40 ± 0.03 to 1.90 ± 0.03 mg/m3) were always higher than indoor ones (from 0.11 ± 0.03 to 0.56 ± 0.03 mg/m3). Not negligible air concentrations of these pollutants were detected in this thermal spring workplace, so further investigations are needed to ensure workers' safety.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminantes Ambientales , Exposición Profesional , Humanos , Contaminantes Atmosféricos/análisis , Exposición Profesional/análisis , Dióxido de Azufre , Minerales , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente
7.
Toxics ; 10(12)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36548601

RESUMEN

BACKGROUND: The disinfection process represents an important activity closely linked to the removal of micro-organisms in common processing systems. Traditional disinfectants are often not sufficient to avoid the spread of food pathogens; therefore, innovative strategies for decontamination are crucial to countering microbial transmission. This study aims to assess the antimicrobial efficiency of tetrapotassium iminodisuccinic acid salt (IDSK) against the most common pathogens present on surfaces, especially in food-borne environments. METHODS: IDSK was synthesized from maleic anhydride and characterized through nuclear magnetic resonance (NMR) spectroscopy (both 1H-NMR and 13C-NMR), thermogravimetric analysis (TGA) and Fourier Transform Infrared (FTIR) spectroscopy. The antibacterial activity was performed via the broth microdilution method and time-killing assays against Escherichia coli, Staphylococcus aureus, Salmonella enterica, Enterococcus faecalis and Pseudomonas aeruginosa (IDSK concentration range: 0.5-0.002 M). The biofilm biomass eradicating activity was assessed via a crystal violet (CV) assay. RESULTS: The minimum inhibitory concentration (MIC) of IDSK was 0.25 M for all tested strains, exerting bacteriostatic action. IDSK also reduced biofilm biomass in a dose-dependent manner, reaching rates of about 50% eradication at a dose of 0.25 M. The advantages of using this innovative compound are not limited to disinfecting efficiency but also include its high biodegradability and its sustainable synthesis. CONCLUSIONS: IDSK could represent an innovative and advantageous disinfectant for food processing and workers' activities, leading to a better quality of food and safer working conditions for the operators.

8.
Toxics ; 10(6)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35736889

RESUMEN

Although being banned or restricted in many countries since the early 1990s, large quantities of asbestos are still used or present in building materials all over the world and its removal or handling requires specific systems that limit exposure to airborne fibers The exposure to asbestos causes chronic diseases such as asbestosis and lung cancer with an incubation period of 20 to 50 years. Among the operators most exposed to contamination are those who handle and analyze the materials in laboratories. For this reason, our work focused on an innovative method for removing a filter unit from a laboratory extraction hood, in order to improve the safety conditions for the operators and the surrounding environment. The hood has a particular construction technology with a mechanism that allows the spraying of a special encapsulating liquid on the ULPA filters below the work-bench, which is capable of forming a film and blocking the fibers on the surface of the same filter. The fibers are irreversibly bounded and can no longer be released into the surrounding environment. The monitoring of activity highlighted the absence of asbestos fibers in the air after installation of the filter and workers feel safer performing their activities. The introduction of an innovative filtering system enhanced the safety of work activities involving asbestos exposure, moreover, the time spent on the hood's maintenance and the risk perception of workers were improved.

9.
Environ Sci Pollut Res Int ; 29(20): 29391-29398, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33813696

RESUMEN

The most important parameter to obtain an appropriate preservation condition of museum environments concerns the indoor air quality. The exposure of artwork and materials to gaseous and particulate pollutants introduced by visitors and either indoor or outdoor sources contributes to their decay. In this work, we evaluated the possible monitoring of the visitors' influence using the stable carbon isotopic ratio of CO2 and the concentration of NH3 as a real-time tool. The study was done in the Refectory of Santa Maria delle Grazie (Milan, Italy) which houses one of the most important paintings of Leonardo da Vinci, the Last Supper, and had more than 400,000 visitors in 2019. The results confirmed a good correlation between the presence of tourists inside the museum and the variation of δ13C value during the visits and the closure of the museum. The variation of indoor atmospheric δ13C was influenced by the presence of visitors in the Refectory and delineates the way done from the entrance to the exit. In the same way, the concentration of NH3 was influenced by the presence of visitors and confirmed the role of this one on preservation methodology for indoor air quality in the museum. This new methodology can be used as a supplemental and non-invasive tool to help in calibrating microclimatic conditions through the ventilation rate and air filtration systems in the museum and to manage the number of visitors per turn.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Pinturas , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Italia , Microclima , Museos
10.
Environ Sci Pollut Res Int ; 29(20): 29409-29418, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34189694

RESUMEN

In this paper, we analysed the efflorescences present in the frescos of a monumental complex named S. Pietro a Corte situated in the historic centre of Salerno (Campania, Italy). The groundwater of the historic centre is fed by two important streams (the Rafastia and the Fusandola) that can be the sources of water penetration. The aims of this work are to (i) identify the stream that reaches the ancient frigidarium of S. Pietro a Corte and (ii) characterize the efflorescences on damaged frescos in terms of chemical nature and sources. In order to accomplish the first aim, the water of the Rafastia river (7 samples) and the water of the Fusandola river (7 samples) were analysed and compared with the water of a well of the Church (7 samples). The ionic chromatography measurements on the water samples allowed us to identify the Rafastia as the river that feeds the ancient frigidarium of S. Pietro a Corte. To investigate the nature and the origin of the efflorescences (our second aim), anionic chromatography analyses, X-ray diffraction measurements, and the isotopic determination of nitrogen were performed on the efflorescences (9 samples) and the salts recovered from the well (6 samples). Results of these analyses show that efflorescences are mainly made of potassium nitrate with a δ15N value of + 9.3 ± 0.2‰. Consequently, a plausible explanation for their formation could be the permeation of sewage water on the walls of the monumental complex.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Nitratos/análisis , Isótopos de Nitrógeno/análisis , Ríos/química , Agua/análisis , Contaminantes Químicos del Agua/análisis
11.
Environ Sci Pollut Res Int ; 29(20): 29385-29390, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33389576

RESUMEN

In this study, we evaluated indoor air quality to highlight the effects of environmental pollution in the field of cultural heritage. In particular, two important archeological places in the old part of the city of Salerno, Italy, were analyzed: Fruscione Palace and S. Pietro a Corte. The work focused on the influence of tourists on environmental pollution correlated to indoor air quality during some social and cultural events. Moreover, we focused on the possible use of the carbon isotopic composition of CO2 as a tool for environmental studies in the field of cultural heritage. The results showed a good relationship between the isotopic composition of CO2 and the variation of pollutants concentration in the air, demonstrating that it is a valid tool and non-invasive marker to monitor environmental pollution of museums and cultural heritage sites.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Dióxido de Carbono , Monitoreo del Ambiente/métodos
12.
Foods ; 10(11)2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34828916

RESUMEN

The carbon stable isotope ratio (δ13C) is a valuable chemical parameter in the investigation of the geographic origin, quality, and authenticity of foods. The aim of this study is the evaluation of the feasibility of 13C-NMR (Nuclear Magnetic Resonance) spectroscopy to determine the carbon stable isotope ratio, at natural abundance, of small organic molecules, such as vanillin, without the use of IRMS (Isotope Ratio Mass Spectrometry). The determination of vanillin origin is an active task of research, and differentiating between its natural and artificial forms is important to guarantee the quality of food products. To reach our goal, nine vanillin samples were analyzed using both 13C quantitative NMR spectroscopy (under optimized experimental conditions) and IRMS, and the obtained δ13C values were compared using statistical analysis (linear regression, Bland-Altman plot, and ANOVA (analysis of variance)). The results of our study show that 13C-NMR spectroscopy can be used as a valuable alternative methodology to determine the bulk carbon isotope ratio and to identify the origin of vanillin. This makes it attractive for the analysis in the same experiment of site-specific and total isotope effects for testing authenticity, quality, and typicality of food samples. Moreover, the improvement of NMR spectroscopy makes it possible to avoid the influence of additives on carbon stable isotope ratio analysis and to clearly identify fraud and falsification in commercial samples.

13.
Toxics ; 9(9)2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34564375

RESUMEN

Recently, studies on microplastics (MPs) have increased rapidly due to the growing awareness of the potential health risks related to their occurrence. The first part of this review is devoted to MP occurrence, distribution, and quantification. MPs can be transferred from the environment to humans mainly through inhalation, secondly from ingestion, and, to a lesser extent, through dermal contact. As regards food web contamination, we discuss the microplastic presence not only in the most investigated sources, such as seafood, drinking water, and salts, but also in other foods such as honey, sugar, milk, fruit, and meat (chickens, cows, and pigs). All literature data suggest not-negligible human exposure to MPs through the above-mentioned routes. Consequently, several research efforts have been devoted to assessing potential human health risks. Initially, toxicological studies were conducted with aquatic organisms and then with experimental mammal animal models and human cell cultures. In the latter case, toxicological effects were observed at high concentrations of MPs (polystyrene is the most common MP benchmark) for a short time. Further studies must be performed to assess the real consequences of MP contamination at low concentrations and prolonged exposure.

14.
Sci Total Environ ; 797: 149206, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34311370

RESUMEN

The growing demand to reduce chlorine usage and control disinfection byproducts increased the development of new strategies in wastewater treatments. Organic peracids are increasingly attracting interest in disinfection activities as a promising alternative to chlorine and chlorine-based agents. In this study, we assessed the antimicrobial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) of a new organic peracid, permaleic acid (PMA) compared with the reference peracetic acid (PAA). Disinfectant properties were evaluated by i) disk diffusion agar, ii) broth microdilution, iii) antibiofilm properties. PMA demonstrated a 10- and 5-fold decrease in the microbial inhibitory concentration (MIC) value against E. coli and S. aureus respectively, compared to PAA. Results showed greater efficacy of PMA regarding wastewater (WW) and treated wastewater (TWW) disinfection at low concentrations. Furthermore, the biofilm degradation ability was only observed following PMA treatment, for both strains. Bacterial regrowth from biofilm matrix after PAA and PMA disinfection, in the absence and presence of organic matter, was evaluated. PMA was more efficient than PAA to prevent the regrowth of planktonic cells of S. aureus and E. coli. After PAA and PMA treatment, in the presence of organic matter, the bacterial regrowth inhibition was maintained up to 10 and 5 g/L, respectively. Based on these results, PMA could be used as a valid alternative to the currently used disinfection methods.


Asunto(s)
Desinfectantes , Ácido Peracético , Desinfectantes/farmacología , Desinfección , Escherichia coli , Ácido Peracético/farmacología , Staphylococcus aureus
15.
Sci Total Environ ; 767: 144395, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33434835

RESUMEN

In this work permaleic acid (PMA) was investigated as possible disinfecting agent and compared to peracetic acid (PAA) in real tap water and wastewater. Preliminary tests in lysogeny broth (LB) were also performed. PMA was synthesized from maleic anhydride and hydrogen peroxide and, for the first time, its antimicrobial activity was evaluated with respect to the growth inhibition of E. coli. The effect of the pH and bivalent ions, typically occurring in real water matrices (namely, Mg2+ and Ca2+), was also investigated. pKa values for PMA were calculated for the first time by DFT calculations. The concentration of bivalent ions strongly affected disinfection efficiency with PMA (Ca2+=0.33 mgL-1 and Mg2+=0.35 mgL-1: 100% E. coli reduction > log 5; Ca2+=13.3 mg L-1 and Mg2+=25.6 mg L-1: E. coli reduction < log 1, after 60 min), and such results were supported by DFT modelling outcomes (pKa2 of PMA 7.3) and disinfection tests in presence of EDTA chelating agent. More alkaline pH conditions drastically decreased PMA disinfection (pH = 5: > log 5 E.coli reduction; pH = 9: < log 1 E.coli reduction, after 60 min). PMA disinfection efficiency is strongly affected by the target water quality, the concentration of metal bivalent ions and the initial pH.


Asunto(s)
Desinfectantes , Purificación del Agua , Desinfección , Escherichia coli , Ácido Peracético , Aguas Residuales
16.
J Infect Public Health ; 13(12): 2038-2044, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33289645

RESUMEN

BACKGROUND: The increasing emergence and spread of multiresistant microorganisms in hospital wards is a serious concern. Traditional protocols are often not sufficient to protect patients susceptible to serious and life-threatening infections, therefore new strategies for decontaminating hospital environments are crucial to reducing microbial transmission and the spread the nosocomial infections. The adoption of modern technologies is indicated to supplement traditional methods and to improve desired levels of surface disinfection. AIM: This work aims to report the development, implementation, and validation of cleansing and sanitizing procedure for critical clinical settings through the innovative use of disposable cloths pre-impregnated with solutions containing different active formulations and biocidal agents, relating to the areas to be treated (low, moderate, high-risk). METHODS: The implementation and validation of the sanitizing system were conducted in different wards of two healthcare structures. The protocol for the study involved a structured selection of representative surfaces, such as the floor, bathroom, desk, and beds. Microbiological analyses were performed according to ISO 4833-1:2013. FINDINGS: The efficiency of the proposed system was measured through the estimation of total microbial count values on the different surfaces before and after the sanitization operations by traditional methods and by the system described here. The results demonstrated a significant reduction in the microbial count that always fell below the threshold value. For the analyzed surfaces such as shower tray, bathroom floor, toilet edge, the traditional system had an effectiveness of less than 10%, whereas pre-impregnated cloths succeed to eliminate about 90% of the bacteria present. As an example, on the floor we observed a microbial count reduction from >42 to 10CFU/11cm2 with the new method (76% of colonies were destroyed), while with the traditional one we have a reduction from >42 to 28CFU/11cm2 (33% of microbial colonies). Moreover, the advantages of using this sanitization system are not limited to disinfecting surfaces and limiting cross-contamination but involve all activities related to the cleaning and disinfection operations, including the training and education of the operators and traceability of the operations. CONCLUSIONS: The innovative disinfection and cleaning protocol used in the present study proved to be a highly valuable alternative to the traditional cleaning procedures in healthcare settings for the sanitizing process of all kinds of surfaces. All tools were specifically designed to improve disinfection efficiency and to reduce the problems associated with traditional methods, such as preventing cross-contamination events, limiting the physical efforts of operators, and avoiding incorrect practices. Our findings add support to the knowledge that an effective sanitization procedure is critical in minimizing microorganisms' transmission and cross-contamination.


Asunto(s)
Infección Hospitalaria , Descontaminación , Infección Hospitalaria/prevención & control , Desinfección , Hospitales , Humanos
17.
Talanta ; 219: 121256, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32887147

RESUMEN

This study focuses on the application of stable carbon isotope analysis to determine the origin of commercial surfactants and cleaning products, especially used in quality process by chemical companies. The δ13C value was applied to commercial surfactants, such as ethoxylate alcohol, sodium lauryl sulfate, alkyl polyglucoside with different origin, that are the most common raw materials used in cleaning products. In this study, the isotopic analysis was performed on mixtures of commercial surfactants to simulate the commercial detergent formulations (handwashing, multisurface cleaner and degreaser) and then on bulk professional cleaning products to match relationship between isotope carbon composition and concentration of surfactants in real samples. This study demonstrated that δ13C was correlated to the origin of surfactants. In particular we analyzed five samples of biobased surfactants, with δ13C value from -22,6‰ to -28,0‰, and six samples from carbon fossil raw material, with δ13C value from -28,5‰ to -32,0‰, which were the most common raw material used in commercial cleaning products. Isotope carbon composition was also applied on mixtures of biobased and fossil surfactants to simulate and perform the method for stable carbon isotope analysis of commercial cleaning products. Furthemore the results assessed the relationship between stable carbon isotope ratio values and surfactant concentration in mixtures: for example in 50% mixtures of biobased (δ13C -22,6‰) and synthetic surfactant (δ13C -32,5‰), we found a δ13C value -28,00‰. The main advantage in using δ13C analysis is related to cheapness and easy-to-operate method in comparison to radiocarbon methodology.


Asunto(s)
Carbono , Tensoactivos , Isótopos de Carbono , Espectrometría de Masas
18.
Water Res ; 184: 116194, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32711221

RESUMEN

The efficiency of a new Advanced Oxidation Process (AOP), namely the photo Fenton like process UV-C/H2O2/IDS-Cu, in removing determinants of antibiotic resistance and pathogenic bacteria was compared to a consolidated AOP (namely UV-C/H2O2) in a secondary treated municipal WasteWater (WW). A reductionist experimental laboratory-based approach was applied on real WW and the parameters were collected by an alternative integrated approach using (i) flow cytometry to enumerate bacteria and test for the fitness of the bacterial communities and (ii) molecular analyses to define the community composition (16S rRNA amplicon sequencing) and the abundances of Antibiotic Resistance Genes (ARGs) and of the class 1 integron (intI1 gene) (by quantitative PCR). The same approach was applied also to post-treatment regrowth tests (24 h) to define the potential persistence of the tested parameters. These experiments were performed in both, human pathogens favorable conditions (HPC, in rich medium and 37°C) and in environmental mimicking conditions (EMC, original WW and 20°C). UV-C/H2O2/IDS-Cu process resulted to be more effective than the UV-C/H2O2in inactivating bacterial cells in the EMC post-treatment regrowth experiments. Both AOPs were efficiently abating potential human pathogenic bacteria and ARGs in the HPC regrowth experiments, although this trend could not be detected in the measurements taken immediately after the disinfection. In comparison with the UV-C/H2O2, the UV-C/H2O2/IDS-Cu process did not apparently offer significant improvements in the abatement of the tested parameters in the WW effluent but, by evaluating the results of the regrowth experiments it was possible to extrapolate more complex trends, suggesting contrasting efficiencies visible only after a few hours. This study offers a detailed view on the abatement efficiency of microbiological/genetic parameters for the UV-C/H2O2/IDS-Cu process, calling for technical adjustments for this very promising technology. At the same time, our results clearly demonstrated the inadequacy of currently applied methodologies in the evaluation of specific parameters (e.g. determinants of antibiotic resistance and pathogenic bacteria) in WW.


Asunto(s)
Aguas Residuales , Purificación del Agua , Antibacterianos/farmacología , Citometría de Flujo , Humanos , Peróxido de Hidrógeno , Oxidación-Reducción , ARN Ribosómico 16S/genética , Rayos Ultravioleta
19.
ChemSusChem ; 12(15): 3448-3452, 2019 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-31282616

RESUMEN

A FeIII -triflate complex, bearing a bis-thioether-di-phenolate [OSSO]-type ligand, was discovered to promote the ring-opening of glycidol with alcohols under mild reaction conditions (0.05 mol % catalyst and 80 °C). The reaction proceeded with high activity (initial turnover frequency of 1680 h-1 for EtOH) and selectivity (>95 %) toward the formation of twelve monoalkyl glyceryl ethers (MAGEs) in a regioselective fashion (84-96 % yield of the non-symmetric regioisomer). This synthetic approach allows the conversion of a glycerol-derived platform molecule (i.e., glycidol) to high-value-added products by using an Earth-crust abundant metal-based catalyst.

20.
Water Res ; 146: 206-215, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30265892

RESUMEN

Photo-Fenton process is among the most effective advanced oxidation processes (AOPs) in urban wastewater treatment and disinfection, but its application as tertiary treatment at full scale has not been a feasible/attractive option so far because optimum conditions are typically achieved under acidic pH. In this work a new photo Fenton like process (UV-C/H2O2/IDS-Cu) using iminodisuccinic acid (IDS)-Cu complex as catalyst, was compared to other processes (UV-C/H2O2/Cu, UV-C/H2O2/Fe, H2O2 and UV-C) in urban wastewater disinfection. Since this is the first time that IDS-Cu complex was isolated and used as catalyst, preliminary tests to evaluate the mineralization of a model compound (phenol, 25 mg L-1 initial concentration) in water by UV-C/H2O2/IDS-Cu were carried out. Almost complete mineralization of phenol (95%) was observed after 60 min treatment, being the process more effective than all other investigated AOPs (Fenton and photo-Fenton processes). This process was also proven to be more effective in the inactivation of E. coli (complete inactivation (3.5 log units) in 10 min) at natural pH (7.8 ±â€¯0.5) in real wastewater, than the other processes investigated. Unlike of what observed for E. coli inactivation, the investigated processes only partially inactivated total bacterial population (from 18% for UV-C to 43% for UV-C/H2O2/Cu), according to flow cytometry measurements. In particular, Cu based photo-Fenton processes resulted in the higher percentage of inactivated total cells, thus being consistent with the results of E. coli inactivation. It is worthy to note that, as H2O2 was decreased, UV-C/H2O2/Cu-IDS was more effective than UV-C/H2O2/Cu process. Moreover, the formation of small and large clusters decreased in the presence of Cu and Cu-IDS complex, and process efficiency improved accordingly; these results show that Cu based AOPs can more effectively disaggregate clusters, thus making disinfection process more effective than Fe based AOPs.


Asunto(s)
Aguas Residuales , Purificación del Agua , Aminoácidos , Desinfección , Escherichia coli , Peróxido de Hidrógeno , Concentración de Iones de Hidrógeno , Hierro , Oxidación-Reducción , Succinatos , Rayos Ultravioleta
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