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This review deals with two overlapping issues, namely polymer chemistry and deep eutectic solvents (DESs). With regard to polymers, specific aspects of synthetic polymers, polymerization processes producing such polymers, and natural cellulose-based nanopolymers are evaluated. As for DESs, their compliance with green chemistry requirements, their basic properties and involvement in polymer chemistry are discussed. In addition to reviewing the state-of-the-art for selected kinds of polymers, the paper reveals further possibilities in the employment of DESs in polymer chemistry. As an example, the significance of DES polarity and polymer polarity to control polymerization processes, modify polymer properties, and synthesize polymers with a specific structure and behavior, is emphasized.
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Nanoestruturas/química , Polímeros/química , Solventes/química , Celulose/química , Química Orgânica , Química Verde , Líquidos Iônicos , Polimerização , Polímeros/classificaçãoRESUMO
The outbreak of the coronavirus disease 2019 (COVID-19) raises questions about the effective inactivation of its causative agent, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in medical wastewater by disinfectants. For this reason, our study of wastewater from a selected hospital evaluated several different advanced oxidation methods (Fenton reaction and Fenton-like reaction and ferrate (VI)) capable of effectively removing SARS-CoV-2 RNA. The obtained results of all investigated oxidation processes, such as ferrates, Fenton reaction and its modifications achieved above 90% efficiency in degradation of SARS-CoV-2 RNA in model water. The efficiency of degradation of real SARS-CoV-2 from hospital wastewater declines in following order ferrate (VI) > Fenton reaction > Fenton-like reaction. Similarly, the decrease of chemical oxygen demand compared to effluent was observed. Therefore, all of these methods can be used as a replacement of chlorination at the wastewater effluent, which appeared to be insufficient in SARS-CoV-2 removal (60%), whereas using of ferrates showed efficiency of up to 99%.
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Nanotechnologies and different types of nanomaterials belong in present day to intensively studied materials due to their unique properties and diverse potential applications in, e.g., electronics, medicine, or display technologies. Together with the investigation of their desired beneficial properties, a need to investigate and evaluate their influence on the environment and possible harmful effects towards living organisms is growing. This review summarizes possible toxic effects of nanomaterials on environment and living organisms, focusing on the possible bioaccumulation in organisms, toxicity, and its mechanisms. The main goal of this review is to refer to potential environmental risks rising from the use of nanomaterials and the necessity to deal with the possible toxic effects considering the growing interest in the wide-scale utilization of these materials. Electron paramagnetic resonance spectroscopy as the only analytical technique capable of detecting radical species enables detection, quantification, and monitoring of the generation of short-lived radicals often coupled with toxic effects of nanomaterials, which makes it an important method in the process of nanotoxicity mechanism determination.
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Nanopartículas , Nanoestruturas , NanotecnologiaRESUMO
New methodologies based on the principle of "sewage epidemiology" have been successfully applied before in the detection of illegal drugs. The study describes the idea of early detection of a virus, e.g., SARS-CoV-2, in wastewater in order to focus on the area of virus occurrence and supplement the results obtained from clinical examination. By monitoring temporal variation in viral loads in wastewater in combination with other analysis, a virus outbreak can be detected and its spread can be suppressed early. The use of biosensors for virus detection also seems to be an interesting application. Biosensors are highly sensitive, selective, and portable and offer a way for fast analysis. This manuscript provides an overview of the current situation in the area of wastewater analysis, including genetic sequencing regarding viral detection and the technological solution of an early warning system for wastewater monitoring based on biosensors.
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COVID-19 , Vigilância Epidemiológica Baseada em Águas Residuárias , Humanos , Mutação , SARS-CoV-2 , Esgotos , Águas ResiduáriasRESUMO
Municipal wastewaters can generally provide real-time information on drug consumption, the incidence of specific diseases, or establish exposure to certain agents and determine some lifestyle consequences. From this point of view, wastewater-based epidemiology represents a modern diagnostic tool for describing the health status of a certain part of the population in a specific region. Hospital wastewater is a complex mixture of pharmaceuticals, illegal drugs, and their metabolites as well as different susceptible and antibiotic-resistant microorganisms, including viruses. Many studies pointed out that wastewater from healthcare facilities (including hospital wastewater), significantly contributes to higher loads of micropollutants, including bacteria and viruses, in municipal wastewater. In addition, such a mixture can increase the selective pressure on bacteria, thus contributing to the development and dissemination of antimicrobial resistance. Because many pharmaceuticals, drugs, and microorganisms can pass through wastewater treatment plants without any significant change in their structure and toxicity and enter surface waters, treatment technologies need to be improved. This short review summarizes the recent knowledge from studies on micropollutants, pathogens, antibiotic-resistant bacteria, and viruses (including SARS-CoV-2) in wastewater from healthcare facilities. It also proposes several possibilities for improving the wastewater treatment process in terms of efficiency as well as economy.
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Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerges to scientific research and monitoring of wastewaters to predict the spread of the virus in the community. Our study investigated the COVID-19 disease in Bratislava, based on wastewater monitoring from September 2020 until March 2021. Samples were analyzed from two wastewater treatment plants of the city with reaching 0.6 million monitored inhabitants. Obtained results from the wastewater analysis suggest significant statistical dependence. High correlations between the number of viral particles in wastewater and the number of reported positive nasopharyngeal RT-qPCR tests of infected individuals with a time lag of 2 weeks/12 days (R2 = 83.78%/R2 = 52.65%) as well as with a reported number of death cases with a time lag of 4 weeks/27 days (R2 = 83.21%/R2 = 61.89%) was observed. The obtained results and subsequent mathematical modeling will serve in the future as an early warning system for the occurrence of a local site of infection and, at the same time, predict the load on the health system up to two weeks in advance.
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COVID-19/epidemiologia , SARS-CoV-2/genética , Águas Residuárias/análise , Águas Residuárias/virologia , COVID-19/mortalidade , Surtos de Doenças/prevenção & controle , Humanos , Modelos Teóricos , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Eslováquia/epidemiologia , Águas Residuárias/química , Vigilância Epidemiológica Baseada em Águas Residuárias , Purificação da ÁguaRESUMO
Waterborne pathogens including viruses, bacteria and micropollutants secreted from population can spread through the sewerage system. In this study, the efficiency of unique effervescent ferrate-based tablets was evaluated for total RNA and DNA removal, disinfection and degradation of micropollutants in hospital wastewater. For the purpose of testing, proposed tablets (based on citric acid or sodium dihydrogen phosphate) were used for various types of hospital wastewater with specific biological and chemical contamination. Total RNA destruction efficiency using tablets was 70-100% depending on the type of acidic component. DNA destruction efficiency was lower on the level 51-94% depending on the type of acidic component. In addition, our study confirms that effervescent ferrate-based tablets are able to efficiently remove of SARS-CoV-2 RNA from wastewater. Degradation of often detected micropollutants (antiepileptic, antidepressant, antihistamine, hypertensive and their metabolites) was dependent on the type of detected pharmaceuticals and on the acidic component used. Sodium dihydrogen phosphate based tablet appeared to be more effective than citric acid based tablet and removed some pharmaceuticals with efficiency higher than 97%. Last but not least, the disinfection ability was also verified. Tableted ferrates were confirmed to be an effective disinfectant and no resistant microorganisms were observed after treatment. Total and antibiotic resistant bacteria (coliforms and enterococci) were determined by cultivation on diagnostic selective agar growth media.
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Various types of micropollutants, e.g., pharmaceuticals and their metabolites and resistant strains of pathogenic microorganisms, are usually found in hospital wastewaters. The aim of this paper was to study the presence of 74 frequently used pharmaceuticals, legal and illegal drugs, and antibiotic-resistant bacteria in 5 hospital wastewaters in Slovakia and Czechia and to compare the efficiency of several advanced oxidations processes (AOPs) for sanitation and treatment of such highly polluted wastewaters. The occurrence of micropollutants and antibiotic-resistant bacteria was investigated by in-line SPE-LC-MS/MS technique and cultivation on antibiotic and antibiotic-free selective diagnostic media, respectively. The highest maximum concentrations were found for cotinine (6700 ng/L), bisoprolol (5200 ng/L), metoprolol (2600 ng/L), tramadol (2400 ng/L), sulfamethoxazole (1500 ng/L), and ranitidine (1400 ng/L). In the second part of the study, different advanced oxidation processes, modified Fenton reaction, ferrate(VI), and oxidation by boron-doped diamond electrode were tested in order to eliminate the abovementioned pollutants. Obtained results indicate that the modified Fenton reaction and application of boron-doped diamond electrode were able to eliminate almost the whole spectrum of selected micropollutants with efficiency higher than 90%. All studied methods achieved complete removal of the antibiotic-resistant bacteria present in hospital wastewaters.
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Ferro/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Águas Residuárias/microbiologia , Boro , Cromatografia Líquida , República Tcheca , Diamante , Farmacorresistência Bacteriana , Eletrodos , Hospitais , Peróxido de Hidrogênio/química , Drogas Ilícitas/análise , Resíduos de Serviços de Saúde , Oxirredução , Preparações Farmacêuticas/análise , Eslováquia , Espectrometria de Massas em Tandem , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/análise , Poluentes Químicos da Água/análiseRESUMO
The scientific community, experts in technology and marketing have been seeking cost-competitive and green solvents with good dissolving capacity for the valorisation of biomass and biowaste. Along with traditional solvents and techniques, deep eutectic solvents (DESs) and their bio-analogues, natural deep eutectic solvents (NADESs) are currently emerging as a new class of promising liquid media. In this review, a comprehensive summary of recent contribution of DESs to the processing and valorisation of various kinds of plant and animal based biomass and biowaste is provided. In the field of food industry based and agro-forest waste valorisation, through treatment of the waste, by-products, and natural materials by DESs, several types of compounds, such as flavonoids and other plant phenolics, phenolic acids, stilbenes, tannins, lignans, and lignin were obtained. Extraction of algae by DESs led to isolation mainly of proteins, carbohydrates, lipids and nucleic acids. Vegetable oils, spent oils, residues and by-products of their processing are a rich source of phenolic compounds such as phenolic acids and phenolic alcohols, secoiridoid derivatives (aglycone and ligstroside), lignans (pino and acetoxypinoresinol), flavones (luteolin and apigein), tocopherols and tocotrienols. Dietary fibre serves as a source of lignin, pectic substances, gums, resistant starch, inulin, as well as non-carbohydrate components, e.g., polyphenols, waxes, saponins, cutin, phytates, resistant proteins. Valorisation of wastes originated from animal processing by DESs means obtaining high-value chemicals including amino acids, proteins, bioactive peptides, collagen peptides, albumin etc. Through the valorisation of the mentioned waste types value-added products with potential applications in the pharmaceutical, food and cosmetic industries are produced. The paper gathered data on the used DESs, treated substances and obtained products, together with treatment conditions and the products yields. The evaluation of the state-of-the-art in the field of biowaste valorisation using DESs and NADESs led to conclusions and indication of future prospects and predicted development in this field.