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1.
Environ Pollut ; 343: 123190, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142809

RESUMO

Microplastic pollution has emerged as a new environmental concern due to our reliance on plastic. Recent years have seen an upward trend in scholarly interest in the topic of microplastics carrying contaminants; however, the available review studies have largely focused on specific aspects of this issue, such as sorption, transport, and toxicological effects. Consequently, this review synthesizes the state-of-the-art knowledge on these topics by presenting key findings to guide better policy action toward microplastic management. Microplastics have been reported to absorb pollutants such as persistent organic pollutants, heavy metals, and antibiotics, leading to their bioaccumulation in marine and terrestrial ecosystems. Hydrophobic interactions are found to be the predominant sorption mechanism, especially for organic pollutants, although electrostatic forces, van der Waals forces, hydrogen bonding, and pi-pi interactions are also noteworthy. This review reveals that physicochemical properties of microplastics, such as size, structure, and functional groups, and environmental compartment properties, such as pH, temperature, and salinity, influence the sorption of pollutants by microplastic. It has been found that microplastics influence the growth and metabolism of organisms. Inadequate methods for collection and analysis of environmental samples, lack of replication of real-world settings in laboratories, and a lack of understanding of the sorption mechanism and toxicity of microplastics impede current microplastic research. Therefore, future research should focus on filling in these knowledge gaps.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Microplásticos/toxicidade , Microplásticos/química , Plásticos/análise , Poluentes Ambientais/toxicidade , Poluentes Ambientais/análise , Ecossistema , Poluentes Químicos da Água/análise , Adsorção
2.
Heliyon ; 9(11): e21227, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954330

RESUMO

The past decade has witnessed a breakthrough in novel strategies to treat cancer. One of the most common cancer treatment modalities is chemotherapy which involves administering anti-cancer drugs to the body. However, these drugs can lead to undesirable side effects on healthy cells. To overcome this challenge and improve cancer cell targeting, many novel nanocarriers have been developed to deliver drugs directly to the cancerous cells and minimize effects on the healthy tissues. The majority of the research studies conclude that using drugs encapsulated in nanocarriers is a much safer and more effective alternative than delivering the drug alone in its free form. This review provides a summary of the types of nanocarriers mainly studied for cancer drug delivery, namely: liposomes, polymeric micelles, dendrimers, magnetic nanoparticles, mesoporous nanoparticles, gold nanoparticles, carbon nanotubes and quantum dots. In this review, the synthesis, applications, advantages, disadvantages, and previous studies of these nanomaterials are discussed in detail. Furthermore, the future opportunities and possible challenges of translating these materials into clinical applications are also reported.

3.
Environ Pollut ; 336: 122473, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37659632

RESUMO

While the study of bioaerosols has a long history, it has garnered heightened interest in the past few years, focusing on both culture-dependent and independent sampling and analysis approaches. Observations have been made regarding the seasonal fluctuations in microbial communities and their connection to particular ambient atmospheric factors. The study of airborne microbial communities is important in public health and atmospheric processes. Nevertheless, the establishment of standardized protocols for evaluating airborne microbial communities and utilizing microbial taxonomy as a means to identify distinct bioaerosols sources and seasonal patterns remains relatively unexplored. This article discusses the challenges and limitations of ambient bioaerosols sampling and analysis, including the lack of standardized methods and the heterogeneity of sources. Future prospects in the field of bioaerosols, including the use of high-throughput sequencing technologies, omics studies, spectroscopy and fluorescence-based monitoring to provide comprehensive incite on metabolic capacity, and activity are also presented. Furthermore, the review highlights the factors that affect bioaerosols composition, including seasonality, atmospheric conditions, and pollution levels. Overall, this review provides a valuable resource for researchers, policymakers, and stakeholders interested in understanding and managing bioaerosols in various environments.


Assuntos
Microbiologia do Ar , Clima , Aerossóis/análise , Poluição Ambiental/análise , Saúde Pública , Monitoramento Ambiental/métodos
4.
Environ Pollut ; 336: 122401, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37598930

RESUMO

This study investigates the size distribution, microbial composition, and antibiotic resistance (ABR) of airborne bioaerosols at a suburban location in Doha, Qatar between October 2021 and January 2022. Samples were collected using an Andersen six-stage viable cascade impactor and a liquid impinger. Findings showed that the mean bacteria concentration (464 CFU/m3) was significantly higher than that of fungi (242 CFU/m3) during the study period. Both bacteria and fungi were most abundant in the aerodynamic size fractions of 1.10-2.21 µm, with peak concentrations observed in the mornings and lowest concentrations in the afternoons across all size fractions. A total of 24 different culturable species were identified, with the most abundant ones being Pasteurella pneumotropica (9.71%), Pantoea spp. 1 (8.73%), and Proteus penneri (7.77%) spp. At the phylum level, the bacterial community configurations during the autumn and winter seasons were nearly identical as revealed by molecular genomics, with Proteobacteria being the most predominant, followed by Firmicutes, Bacteroidetes, Acidobacteriota, and Planctomycetota. However, there was a significant variation in dominant genera between autumn and winter. The most abundant genera included Sphingomonas, Paraburkholderia, Comamonas, Bacillus, and Lysinibacillus. Several bacterial genera identified in this study have important public health and ecological implications, including the risk of respiratory tract infections. Furthermore, the study found that ABR was highest in December, with bioaerosols exhibiting resistance to at least 5 out of 10 antibiotics, and 100% resistance to Metronidazole in all samples. Metagenomics analysis revealed the presence of various airborne bacteria that were not detected through culture-dependent methods. This study provides valuable insights into the airborne microbial composition, temporal variability and ABR in the Arabian Gulf region.

5.
Environ Sci Pollut Res Int ; 30(44): 98895-98906, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36036347

RESUMO

This work presents a novel triple-renewable energy system (TRES) that is based on integrating the photovoltaic panels (PVPs), conventional solar chimney (CSC), and cooling tower (CT) in one structure. The ultimate objective of the proposed TRES system is to produce electrical power (Pelc), desalinated water (Dw), and if required cooling utilities. The components of the system include a chimney tower, collector, base, PVPs, water pool, bi-directional turbine, and water sprinklers. The TRES system can be operated as CSC during the daytime and CT at night providing 24-h operation. The PVPs were integrated within the structure to increase the Pelc production and enhance the process performance by heating the air inside the system. The TRES structure increased the efficiency to 0.860% in comparison with the CSC (0.313%). The annual Pelc production from the TRES system was found to be 792 MWh compared with only 380 MWh generated by the CSC achieving 2.1 folds overall improvement. The CSC-PV and CT contributed to 47% (494 MWh) and 24% (253 MWh) of the Pelc production, respectively. The annual Dw production was found to be 1.2-fold higher (163,142 tons) higher than the CSC (139,443 tons). The newly developed TRES system offers a great potential to produce Pelc and Dw and save fossil fuel consumption while reducing the emissions of greenhouse gasses (GHGs) to the atmosphere.


Assuntos
Energia Solar , Água , Energia Renovável , Luz Solar , Combustíveis Fósseis , Eletricidade
6.
Nanomaterials (Basel) ; 12(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35457948

RESUMO

A simple temperature-assisted solution interaction technique was used to functionalize and reduce graphene oxide (GO) using tetraethylenepentamine (TEPA) with less chemicals, low temperature, and without using other reducing agents. GO nanosheets, produced using a modified Hummers' method, were functionalized using two different GO:TEPA ratios (1:5 and 1:10). The reduction of GO was evaluated and confirmed by different spectroscopic and microscopic techniques. The FTIR and XPS spectra revealed that most of the oxygenated groups of GO were reduced. The emergence of amide groups in the XPS survey of the rGO-TEPA samples confirmed the successful reaction of TEPA with the carboxyl groups on the edges of GO. The replacement of the oxygenated groups increased the carbon/oxygen (C/O) ratio of GO by approximately 60%, suggesting a good reduction degree. It was found that the I2D/ID+D' ratio and the relative intensity of the D″ band clearly increased after the reduction reaction, suggesting that these bands are good estimators for the reduction degree of GO. The morphological structure of GO was also affected by the reaction with TEPA, which was confirmed by SEM and TEM images. The TEM images showed that the transparent GO sheets became denser and opaque after functionalization with TEPA, indicating an increase in the stacking level of the GO sheets. This was further confirmed by the XRD analysis, which showed a clear decrease in the d-spacing, caused by the removal of oxygenated groups during the reduction reaction.

7.
Membranes (Basel) ; 12(1)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35054621

RESUMO

Diffusion dialysis (DD) is an anion exchange membrane-based functional separation process used for acid recovery. TMA (trimethylamine) and BPPO (brominated poly(2,6-dimethyl-1,4-phenylene oxide) were utilized in this manuscript to formulate AEMs (anion exchange membranes) for DD (diffusion dialysis) using the phase-inversion technique. FTIR (Fourier transfer infrared) analysis, proton NMR spectroscopy, morphology, IEC (ion exchange capacity), LER (linear expansion ratio), CR (fixed group concentration), WR (water uptake/adsorption), water contact angle, chemical, and thermal stability, were all used to evaluate the prepared membranes. The effect of TMA content within the membrane matrix on acid recovery was also briefly discussed. It was reported that porous AEMs have a WR of 149.6% to 233.8%, IEC (ion exchange capacity) of 0.71 to 1.43 mmol/g, CR (fixed group concentration) that ranged from 0.0046 mol/L to 0.0056 mol/L, LER of 3.88% to 9.23%, and a water contact angle of 33.10° to 78.58°. The UH (acid dialysis coefficients) for designed porous membranes were found to be 0.0043 to 0.012 m/h, with separation factors (S) ranging from 13.14 to 32.87 at the temperature of 25 °C. These observations are comparable to those found in the DF-120B commercial membrane with UH of 0.004 m/h and S of 24.3 m/h at the same temperature (25 °C). This porous membranes proposed in this paper are excellent choices for acid recovery through the diffusion dialysis process.

8.
Bioresour Technol ; 347: 126687, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35007740

RESUMO

Thermal co-processing of lignocellulosic and aquatic biomass, such as algae and shellfish waste, has shown synergistic effects in producing value-added energy products with higher process efficiency than the traditional method, highlighting the importance of scaling up to pilot-scale operations. This article discusses the design and operation of pilot-scale reactors for torrefaction, pyrolysis, and gasification, as well as the key parameters of co-processing biomass into targeted and improved quality products for use as fuel, agricultural application, and environmental remediation. Techno-economic analysis reveals that end product selling price, market dynamics, government policies, and biomass cost are crucial factors influencing the sustainability of thermal co-processing as a feasible approach to utilize the biomass. Because of its simplicity, pyrolysis allows greater energy recovery, while gasification has the highest net present value (profitability). Integration of liquefaction, hydrothermal, and fermentation pre-treatment technology has the potential to increase energy efficiency while reducing process residues.


Assuntos
Biocombustíveis , Lignina , Biomassa , Frutos do Mar
9.
Chemosphere ; 287(Pt 4): 132387, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34600004

RESUMO

MXene-based nanomaterials (MBNs) are two-dimensional materials that exhibit a series of sought after properties, including rich surface chemistry, adjustable bandgap structures, high electrical conductivity, hydrophobicity, thermal stability, and large specific surface area. MBNs have an exemplar performance when applied for the degradation of hazardous pollutants with various advanced oxidation processes such as heterogeneous sonocatalysis. As such, this work focuses on the sonocatalytic degradation of various hazardous pollutants using MXene-based catalysts. First, the general principles of sonocatalysis are examined, followed by an analysis of the main components of the MXene-based sonocatalysts and their application for pollutant degradation. Lastly, ongoing challenges are highlighted with recommendations to address the issues.


Assuntos
Poluentes Ambientais , Nanoestruturas , Catálise , Condutividade Elétrica
10.
Chemosphere ; 288(Pt 2): 132559, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34655643

RESUMO

Global production of shellfish aquaculture is steadily increasing owing to the growing market demands for shellfish. The intensification of shellfish aquaculture to maximize production rate has led to increased generation of aquaculture waste streams, particularly the effluents and shellfish wastes. If not effectively managed, these wastes could pose serious threats to human health and the ecosystem while compromising the overall sustainability of the industry. The present work comprehensively reviews the source, composition, and environmental implications of shellfish wastes and aquaculture wastewater. Moreover, recent advancements in the valorization of shellfish wastes into value-added biochar via emerging thermochemical and modification techniques are scrutinized. The utilization of the produced biochar in removing emerging pollutants from aquaculture wastewater is also discussed. It was revealed that shellfish waste-derived biochar exhibits relatively higher adsorption capacities (300-1500 mg/g) compared to lignocellulose biochar (<200 mg/g). The shellfish waste-derived biochar can be effectively employed for the removal of various contaminants such as antibiotics, heavy metals, and excessive nutrients from aquaculture wastewater. Finally, future research priorities and challenges faced to improve the sustainability of the shellfish aquaculture industry to effectively support global food security are elaborated. This review envisages that future studies should focus on the biorefinery concept to extract more useful compounds (e.g., carotenoid, chitin) from shellfish wastes for promoting environmental-friendly aquaculture.


Assuntos
Ecossistema , Purificação da Água , Aquicultura , Carvão Vegetal , Humanos , Frutos do Mar
11.
Chemosphere ; 286(Pt 3): 131892, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34418663

RESUMO

The research and technological advancements observed in the latest years in the nanotechnology field translated into significant application developments in various areas. This is particularly true for the renewable polymers area, where the nano-reinforcement of biobased materials leads to an increase in their technique and economic competitiveness. The efforts were predominantly focused on materials development and energy consumption minimization. However, attention must also be given to the widespread commercialization and the full characterization of any particular potential toxicological and environmental impact. Some of the most important nanomaterials used in recent years as fillers in the bioplastic industry are graphene-based materials (GBMs). GBMs have high surface area and biocompatibility and have interesting characterizations such as strangeness and flexibility. In this paper, the current state of the art for these GBMs in the bioplastics area, their challenges, and the strategies to overcome them are analyzed.


Assuntos
Grafite , Nanoestruturas , Nanotecnologia , Polímeros
12.
J Hazard Mater ; 423(Pt A): 127016, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34474364

RESUMO

This study evaluates the degradation efficiency of Malathion using Fenton (Fe2+/H2O2: F), photo-Fenton (UV/Fe2+/H2O2: PF), and sono-photo Fenton (US/UV/Fe2+/H2O2: SPF) processes as well as determines the toxicity of the byproducts of degradation. The effect of various operational parameters on the Malathion degradation rate, including pH, Fe2+ concentration, Malathion concentration, and H2O2 were studied. The removal efficiency was determined to be 98.79% for the SPF, > 70.92% for the PF, and > 55.94% for the F processes under the following optimal conditions: pH = 3, [H2O2]0 = 700 mg/L, [Fe2+]0 = 20 mg/L, and [Malathion]0 = 20 mg/L. The operating costs (USD/kgMalathion-removed) were acquired as SPF > PF > F. Moreover, Malaoxon, diethyl maleate, diethyl malate, ethyl 2-hydroxysuccinate, and D-malate were among the detected byproducts from the Malathion degradation in the SPF process. Both the non-carcinogenic risk and the carcinogenic risk were assessed to establish the quality of the effluent from all three processes. The toxicity of the treated effluents, determined by Vibrio fischeri luminescence, indicated that the toxicity depends on the selected treatment process. The high degradation efficiency of the Fenton-based processes is not equivalent to achieving detoxification of the effluents. As such, the SPF process was determined to be the most effective for the Malathion degradation, total organic carbon (TOC) removal, and health risk assessment.


Assuntos
Praguicidas , Poluentes Químicos da Água , Descontaminação , Peróxido de Hidrogênio/toxicidade , Ferro , Malation/toxicidade , Oxirredução , Praguicidas/toxicidade , Medição de Risco , Raios Ultravioleta , Poluentes Químicos da Água/toxicidade
13.
Chemosphere ; 286(Pt 1): 131479, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34315081

RESUMO

The present work investigates for the first time the presence and isolation of the thermophilic fungi from hydrothermal spring situated at the locality of Guelma, in the Northeast of Algeria. The production of the thermostable proteases and the optimization of culture conditions under agro-wastes solid-state fermentation to achieve optimal production capacity were explored. A statistical experimental approach consisting of two designs was used to determine the optimum culture conditions and to attain the greatest enzyme production. Besides, different agricultural wastes were initially evaluated as a substrate, whereby wheat bran was selected for enzyme production by the isolate under solid-state conditions. The isolate thermophilic fungi were identified as Mycothermus thermophilus by sequencing the ITS region of the rDNA (NCBI Accession No: MK770356.1). Among the various screened variables: the temperature, the inoculum size, and the moisture were proved to have the most significant effects on protease activity. Employing two-level fractional Plackett-Burman and a Box-Behnken designs statistical approach helped in identifying optimum values of screened factors and their interactions. The analysis showed up 6.17-fold improvement in the production of proteases (~1187.03 U/mL) was achieved under the optimal conditions of moisture content 47%, inoculum 5 × 105 spores/g, and temperature at 42 °C. These significant findings highlight the importance of the statistical design in isolation of Mycothermus thermophilus species from a specific location as well as identifying the optimal culture conditions for maximum yield.


Assuntos
Peptídeo Hidrolases , Argélia , Fermentação , Peptídeo Hidrolases/genética , Sordariales , Temperatura
14.
J Hazard Mater ; 421: 126719, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34364215

RESUMO

The photocatalytic degradation of pharmaceutical micropollutants of Penicillin G (PG) was investigated in a photoreactor at a laboratory scale. The impact of type of catalyst, pH, and initial concentration of PG were studied. Maximum removal efficiency was obtained at pH = 6.8, [ZnO]0 = 0.8 g L-1, and [PG]0 = 5 mg L-1 and reaction time of 150 min. The addition of persulfate sodium (PPS) enhanced the efficiency of the photocatalytic reaction. The efficiency of photolysis process in the presence of PPS was significantly improved to 72.72% compared to the classical photocatalysis system (56.71%). Optimum concentration of PPS to completely degraded PG was found to be 500 mg L-1. The QuEChERS extraction, GC-MS/MS method, and concentration technique showed favorable performance identification of the possible mechanism of PG degradation pathway. Toxicity of PG and its by-products were evaluated using microbioassays assessment based on nine selected bacterial strains. Results confirmed the effectiveness of the implemented system and its safe use via the bacteria Bacillus subtilis, which has illustrated significant activity. Due to the high efficiency, facility benefits, and low-cost of the suggested process, the process can be considered for the degradation of various pharmaceutical contaminants in pharmaceutical industry treatment under the optimal conditions.


Assuntos
Espectrometria de Massas em Tandem , Poluentes Químicos da Água , Catálise , Cinética , Penicilina G , Fotólise
15.
Chemosphere ; 286(Pt 2): 131730, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34364231

RESUMO

Coffee is a globally consumed beverage that produces a substantial amount of valuable organic waste known as spent coffee grounds (SCG). Although SCG is a non-edible biomass, research initiatives focused on valorizing/utilizing its organic content, protecting the environment, and reducing the high oxygen demand required for its natural degradation. The integration with biorefinery in general and with pyrolysis process in specific is considerered the most successful solid waste management strategy of SCG that produce energy and high-value products. This paper aims at providing a quantitative analysis and discussion of research work done over the last 20 years on SCG as a feedstock in the circular bioeconomy (CBE). Management stratigies of SCG have been thoroughly reviewed and pyrolysis process has been explored as a novel technology in CBE. Results revealed that explored articles belong to Chemical, physical., biological and environmental science branches, with Energy & Fuels as the most reporting themes. Published works correlate SCG to renewable energy, biofuel, and bio-oil, with pyrolysis as a potential valorization approach. Literature review showed that only one study focused on the pyrolysis of defatted spent coffee grounds (DSCG). The insightful conclusions of this paper could assist in proposing several paths to more economically valorization of SCG through biorefinery, where extracted oil can be converted to biofuels or value-added goods. It was highlighted the importance of focusing on the coupling of SCG with CBE as solid waste managment strategy.


Assuntos
Café , Gerenciamento de Resíduos , Biocombustíveis , Pirólise , Resíduos Sólidos
16.
Environ Res ; 203: 111845, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34384753

RESUMO

The best exceptional Physico-chemical attributes of MXenes including high conductivity, high surface area, high functionalization, hydroxide site, and other interesting properties have attracted recently the attention of scientists in the applications of MXene (Mn+1XnTx)-based nanomaterials for water treatment. To provide a full and comprehensive vision of the current state of the art, and improve the treatment performance, and motivate new researches in this area, this review focused on the uses of these novel 2D transition metal carbides for desalination of water and the general methods of fabrication of MXenes; thus, MXene-based nanomaterials are very efficient candidates in water desalination processes, in this review, the main properties of previous and current works about MXenes applications in this area were properly investigated. Moreover, a particular overview about the different properties of MXenes in desalination such as etching method, hydrophobicity, structural modification, and chemical modification has been performed; meanwhile, the investigation of MXenes and MXenes-based composites would be an excellent candidate in the future of water purification and environmental remediation fields, since they have several good properties compared to the other 2D materials.


Assuntos
Recuperação e Remediação Ambiental , Nanoestruturas , Elementos de Transição , Purificação da Água
17.
Chemosphere ; 286(Pt 2): 131821, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34388869

RESUMO

Acute exposure to trace metals (TMs) in water is hazardous to human health. The average concentrations (Cavg.) and carcinogenic (CAR) and non-carcinogenic (non-CAR) risks of eight TMs to World Health Organization's (WHO) guidelines and national standard limits (NSLs)were determined. The Cavg. and (the range) of As, Hg, Cd, Pb, Co, Cr, Ni, and Zn were measured as 4.29 ± 0.57 µg L-1 (1.12-10.27 µg L-1), 0.22 ± 0.10 µg L-1 (ND-1.05 µg L-1), 0.31 ± 0.18 µg L-1 (ND-1.80 µg L-1), 4.66 ± 0.32 µg L-1 (0.10-14.22 µg L-1), 24.61 ± 4.65 µg L-1 (3.11-67.25 µg L-1), 16.86 ± 5.54 µg L-1 (5.12-34.61 µg L-1), 14.07 ± 4.37 µg L-1 (3.79-31.39 µg L-1), and 268.42 ± 75.82 (87.29-561.22 µg L-1), respectively. The Cavg. of Co and Hg exceeded the WHO and NSLs. The non-CAR risk assessment was used to order the TMs according to the total target hazard quotient (TTHQ) As > Pb > Cr > Co > Zn > Hg > Ni > Cd. None of the investigated age groups are at risk As there is a low Cavg of all trace metals (i.e., the THQ is > 1). The age groups were ranked based on THQ and incremental lifetime cancer risk (ILCR) As < 1 year, >1-10 years, > 11-19 years, and > + 20 years. The ILCR of As for all the age groups was >10-4, whereas for Pb it was <10-6. Cumulative carcinogenic risk (CCR) for As and Pb was at a safe threshold risk (>10-4) for all the age groups.


Assuntos
Água Potável , Mercúrio , Metais Pesados , Oligoelementos , Monitoramento Ambiental , Intoxicação por Metais Pesados , Humanos , Lactente , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Oligoelementos/análise , Oligoelementos/toxicidade
18.
Chemosphere ; 286(Pt 2): 131727, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34352554

RESUMO

Due to its cytotoxic effect, metronidazole (MNZ) is a drug commonly used to treat bacterial, protozoal, and microaerophilic bacterial infections. After consumption, it undergoes a series of metamorphic reactions that lead to the degradation of oxidized, acetylated, and hydrolyzed metabolites in the environment. To eliminate such pollutants, due to their high potential, adsorption and photocatalysis extensive processes are used in which graphene can be used to improve efficiency. This review analyses the use of graphene as an absorbent and catalyst with a focus on absorption and photocatalytic degradation of MNZ by graphene-based materials (GBMs). The parameters affecting the adsorption, and photocatalytic degradation of MNZ are investigated and discussed. Besides, the basic mechanisms occurring in these processes are summarized and analyzed. This work provides a theoretical framework that can direct future research in the field of MNZ removal from aqueous solutions.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Catálise , Metronidazol/análise , Poluentes Químicos da Água/análise
19.
Chemosphere ; 291(Pt 2): 132789, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34742763

RESUMO

Pesticide applications and the proximity of land use to water matrices have resulted in discharges of pollutants including Malathion -one of the most widely used organophosphorus pesticides- to water resources such as marine, freshwater, and under groundwater. Exposure to malathion through consumption of contaminated water may cause deleterious health effects on consumers. Determining the amount of pesticides used on farms can play an important role in preventing potential toxicity and pollution of nearby aquatic ecosystems. Therefore, this systematic review and meta-analysis is focused on evaluating the concentrations of Malathion in water resources while considering probabilistic health risk assessment. The international databases of Scopus, Embase, and PubMed were investigated to evaluate the related articles from January 01, 1968 to March 25, 2021. Thirty-four articles containing 206 samples from 15 countries were included. A meta-analysis of carcinogenic and non-carcinogenic risk assessments for Malathion was also performed. To determine uncertainty intervals, a Monte-Carlo simulation was conducted. The results of the meta-analysis showed that the rankings of Malathion pollution (from the most to the least) were: drinking water > surface waters > groundwaters. Moreover, the results of the risk assessments confirm that there is no non-carcinogenic risk for any of the study areas. The carcinogenic risk assessment was within the limit for the countries under this study, except for Ethiopia that was slightly over the limit as well as Iran, and Mexico had high carcinogenic risk.


Assuntos
Água Potável , Praguicidas , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Malation/toxicidade , Compostos Organofosforados , Praguicidas/análise , Medição de Risco , Poluentes Químicos da Água/análise
20.
Chemosphere ; 291(Pt 2): 133036, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34822867

RESUMO

The recurrent environmental and economic issues associated with the diminution of fossil fuels are the main impetus towards the conversion of agriculture, aquaculture and shellfish biomass and the wastes into alternative commodities in a sustainable approach. In this review, the recent progress on recovering and processing these biomass and waste feedstocks to produce a variety of value-added products via various valorisation technologies, including hydrolysis, extraction, pyrolysis, and chemical modifications are presented, analysed, and discussed. These technologies have gained widespread attention among researchers, industrialists and decision makers alike to provide markets with bio-based chemicals and materials at viable prices, leading to less emissions of CO2 and sustainable management of these resources. In order to echo the thriving research, development and innovation, bioresources and biomass from various origins were reviewed including agro-industrial, herbaceous, aquaculture, shellfish bioresources and microorganisms that possess a high content of starch, cellulose, lignin, lipid and chitin. Additionally, a variety of technologies and processes enabling the conversion of such highly available bioresources is thoroughly analysed, with a special focus on recent studies on designing, optimising and even innovating new processes to produce biochemicals and biomaterials. Despite all these efforts, there is still a need to determine the more cost-effective and efficient technologies to produce bio-based commodities.


Assuntos
Materiais Biocompatíveis , Lignina , Agricultura , Aquicultura , Biocombustíveis , Biomassa , Frutos do Mar
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