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1.
Ecotoxicol Environ Saf ; 277: 116369, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38678793

RESUMEN

Understanding the new insight on conversion of organic waste into value-added products can improve the environmental activities driven by microorganisms and return the nutrients to environment and earth. Here, we comprehensively review the available knowledge on application of garbage enzyme (GE) for different environmental activities including waste activated sludge, composting process, landfill leachate treatment, soil remediation and wastewater treatment with special focus on their efficiency. To identify peer-reviewed studies published in English-language journals, a comprehensive search was performed across multiple electronic databases including Scopus, Web of Science, Pubmed, and Embase. The search was conducted systematically using relevant keywords. The eligible studies were analyzed to extract data and information pertaining to components of GE, fermentation process operational parameters, type of hydrolytic enzymes and improved environmental performance. The findings derived from this current review demonstrated that GE produced from the fruit and vegetable peels, molasses or brown sugar (carbon source), and water within fermentation process contain different hydrolytic enzymes in order to facilitate the organic waste degradation. Therefore, GE can be considered as a promising and efficient pathway in order to improve the environmental activities depended on microorganism including, composting, wastewater and leachate treatment and bioremediation process.


Asunto(s)
Biodegradación Ambiental , Enzimas , Residuos de Alimentos , Compostaje , Enzimas/metabolismo , Fermentación , Aguas del Alcantarillado/microbiología , Aguas Residuales/química
2.
Environ Geochem Health ; 46(9): 324, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012397

RESUMEN

Air pollution from Potentially Hazardous Elements bound with particulate matter (PHEs bound PM) in landfill air is a significant concern for human health. To date, no comprehensive research has focused on the health risks of PHEs bound to PM in landfill air. This systematic review aimed to examine PHEs, including Lead (Pb), Cadmium (Cd), Chromium (Cr), Arsenic (As), Nickel (Ni), and Zinc (Zn) bound with PM in landfill air and assess the health risk for workers and waste management personnel. The systematically search was made in different electronic databases. After the screening, 18 most relevant studied focused on PHEs bound PM in landfill air were selected. The data extraction analysis indicated that mean concentrations of Pb, Cd, Cr, As, Ni, and Zn in landfill air were 0.3037, 0.0941, 0.4093, 0.0221, 0.2768, and 0.7622 µg/m3, respectively. Except for Pb, the concentrations of other PHEs bound to PM exceeded USEPA air quality standards. In addition, Non-carcinogenic risks from Cd, Cr, and Ni exposure exceeded permissible limits (HQ > 1), while As had an HQ value of 0.401. Carcinogenic risks from As, Cd, Ni, and Pb exposure were 1.31 × 10-5, 5.10 × 10-4, 3.51 × 10-5, and 2.03 × 10-6, respectively. Notably, the lifetime carcinogenic risk for workers exposed to Cr in polluted air (6.17 × 10-3) exceeded permissible limits (10-4 to 10-6). In conclusion, given the high carcinogenic and non-carcinogenic risks of some PHEs bound PM in landfills, it is necessary to conduct more research on the health effects of interaction with these PHEs bound PM on communities and the environment in different countries. Also, it is necessary to evaluate the role of different landfill operational activities on atmospheric dispersion of PHEs bound PM) in landfill air.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Instalaciones de Eliminación de Residuos , Medición de Riesgo , Material Particulado/análisis , Humanos , Contaminantes Atmosféricos/análisis , Metales Pesados/análisis , Sustancias Peligrosas/análisis , Monitoreo del Ambiente , Exposición Profesional
3.
Waste Manag Res ; 41(2): 368-375, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35959868

RESUMEN

Littered waste is one of the ubiquitous problems in urban environments. In this study, urban environmental pollution was evaluated for the first time using a new developed index. The findings indicated that cigarette butts with an average 58% are the largest share in the composition of littered waste. In addition, the numbers of littered wastes throughout the study area had a spatial variation. According to clean environment index (CEI), the entire study area was found to be in a moderate status. However, 40% of the study areas were classified in a dirty and extremely dirty status. Comparison of the studied urban land-uses showed that residential land use with CEI equal to 3.38 is interpreted in the clean status, while commercial land use with CEI equal to 15.05 can be classified in the dirty status. The application of CEI has a good capability to assess littered waste; this index can be employed to evaluate the pollution of urban sidewalks and other environments such as beaches.


Asunto(s)
Monitoreo del Ambiente , Productos de Tabaco , Contaminación Ambiental , Residuos , Plásticos , Playas
4.
Ecotoxicol Environ Saf ; 247: 114222, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36323151

RESUMEN

Here, a combined pretreatment oxidation process (O3/H2O2) was investigated to enhance the biodegradability of raw landfill leachate (RLL) and biomethane potential (BMP) in anaerobic reactors. The central composite design (CCD) and response surface methodology (RSM) were employed to optimize the operational parameters influencing on RLL bioavailability in O3/H2O2 process: pH, Oxygen Flow rate, Reaction Time, and H2O2 concentration. The findings revealed that the O3/H2O2 increased biodegradability index (BOD5/COD) of RLL from 0.41 to 0.68 under optimized condition (pH=8, Oxygen flow= 0.25 L.min-1, Reaction Time= 25 min, H2O2 concentration= 2.5 g.L-1). Furthermore, the effects of O3/H2O2 process on BMP of RLL were surveyed under mesophilic anaerobic reactors (Temperature: 37 ± 1 °C) in viewpoints of operational performance and methane yield in a batch mode for incubation period of 24 days. The results showed that O3/H2O2 process simultaneously improve the BMP by 2.99 times higher in a shorter lag-phase period (5 days) compared with control. The pretreatment O3/H2O2 and mesophilic anaerobic digestion process revealed a feasible and efficient method for enhance BMP of RLL.


Asunto(s)
Biocombustibles , Contaminantes Químicos del Agua , Anaerobiosis , Peróxido de Hidrógeno , Oxígeno
5.
J Environ Manage ; 294: 112962, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34102467

RESUMEN

In this study, bentazon herbicide was degraded photocatalytically by copper doped zinc oxide nanorods fabricated by using a facile co-precipitation method. The crystal structure, morphology, surface composition, functional groups on the surface and valence state of the nanorods were investigated by XRD, SEM-EDX, FTIR, and XPS material characterization techniques. Environmental parameters including solution pH, catalyst dose, bentazon concentration, purging gases, H2O2 content, organic compound type and reusability affecting the rate of photocatalytic degradation of bentazon were evaluated. Under the optimal conditions, [Bentazon]0 = 20 mg L-1, Cu-ZnO loading = 0.5 g L-1, H2O2 = 2 mM, pH = 7 and in the presence of oxygen gas, 100% of the herbicide was removed within 60 min. By raising bentazon concentration (10-50 mg L-1), kobs decreased to values between 0.14 and 0.006 min-1 and the calculated electrical energy per order (EEo) increased from 38.16 to 727.27 (kWh m-3), respectively. The degradation removal of the herbicide using the UV/Cu-ZnO method (98.28%) was higher than that of the UV/ZnO method (32.14%) process. Interestingly, the photocatalytic performances in the first and fifth reuse cycles during catalyst recyclability tests were found to be similar. Generally, the efficacy of the method in the decomposition of bentazon in drinking water (78.95%) and actual sewage (46.77%) declined because of the presence of other anions due to their role as a scavenger of photogenerated reactive species. Intermediate products in the photocatalytic degradation of bentazon identified by gas chromatography/mass spectrometry (GC/MS) analysis were 2-amino-N-isopropyl-benzamide, 2-amino-benzoic acid, N-isopropyl-2-nitro-benzamide, and acids such as pentenedioic acid, oxalic acid and propenoic acid. Furthermore, the main mechanism for the photocatalytic removal of bentazon was determined to be via attack by hydroxyl radicals (•OH). The results of toxicity in the photocatalytic removal of bentazon by D. magna showed LC50 and toxicity unit (TU) 48 h equal to 46.10 and 9.56 vol percent.


Asunto(s)
Nanotubos , Óxido de Zinc , Benzotiadiazinas , Catálisis , Cobre , Peróxido de Hidrógeno
6.
J Egypt Public Health Assoc ; 96(1): 28, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34698971

RESUMEN

BACKGROUND: Assessment of benefits and barriers of waste separation at source is necessary to identify the effective factors in this field. This study aims at designing and validation of a questionnaire assessing the barriers and benefits of waste separation at source from the viewpoint of women based on the community-based social marketing model in Genaveh Township, Bushehr, Iran METHODS: In phase 1, a literature review and focus group discussion were conducted to identify the barriers and benefits of waste separation at the source and to design the items and questionnaires. In phase 2, a psychometric evaluation was performed, including face validity, content validity, structural validity, and reliability. Data were analyzed by SPSS and R software. RESULTS: Out of 56 initial items, seven items with the content validity ratio less than 0.56 were removed, and one with the content validity index less than 0.79 was reviewed. Content validity ratio of the questionnaire was 0.782 and content validity index 0.957. The results of exploratory factor analysis showed that the five and seven-factor models showed good fit. Considering the possible existence of some items in several factors, confirmatory factor analysis was used in the next step. Finally, two items were removed and two others were displaced. The reliability of the instrument was confirmed by internal consistency (α = 0.92) and its stability by the test-retest (ICC = 0.83). CONCLUSIONS: The valid and reliable 48-item questionnaire is a suitable instrument for assessing the barriers and benefits of waste separation at source from the viewpoint of women based on the community-based social marketing model in Genaveh Township, Bushehr.

7.
Ecotoxicol Environ Saf ; 202: 111015, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32800237

RESUMEN

The risk of newly emerging diseases is constantly present in a world where changes occur significantly in climatic, commercial, and ecological conditions, in addition to the development of biomedical investigations in new situations. An epidemic respiratory disease instigated by a new coronavirus was initially identified in and has resulted in the current global dissemination. This viral strain and its related disease has been termed "SARS-CoV-2" and "coronavirus disease 2019" (abbreviated "COVID-19" or "2019-nCoV"), respectively, which is transmitted simply between individuals. The World Health Organization (WHO) announced the COVID-19 outburst as a pandemic on March 11, which necessitates a cooperative endeavour globally for mitigating the spread of COVID-19. The absence of previous, and minimum present-day information, particularly concerning the path of contagion have precluded the control of this disease. The present article, therefore, describes the SARS-CoV-2 paths of contagion such as drinking water, solid waste, sewer water, ambient air, and the rest of emerging likely paths.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/transmisión , Reservorios de Enfermedades , Exposición a Riesgos Ambientales , Neumonía Viral/transmisión , Enzima Convertidora de Angiotensina 2 , Betacoronavirus/patogenicidad , COVID-19 , Infecciones por Coronavirus/metabolismo , Infecciones por Coronavirus/virología , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Humanos , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/metabolismo , Neumonía Viral/virología , SARS-CoV-2 , Organización Mundial de la Salud
8.
Waste Manag Res ; 38(1): 44-58, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31438782

RESUMEN

The main objective of this research was to investigate the waste characteristics and management activities in the Savojbolagh industrial zone, Iran, in order to rank the active industries from environmental perspectives using an innovative index. First, the industrial categories with over 50 employees were identified and classified according to their production process. Then, 54 industries were selected and all industrial processes, the types and quantities of products, per capita industrial waste generation, physical analysis and management activities in terms of minimisation, storage, processing, recycling and disposal were evaluated. The required data were obtained through questioners, interviews and field observations. A scoring system was prepared for evaluation of environmental status of waste management practices. Results indicated that the total industrial waste generation rate was 67,258 kg d-1, in which 4528 belonged to hazardous waste. Furthermore, the per capita waste generation rate was 5.51 kg d-1. Plastic, paper and cardboard and metals constituted the most fractions of wastes, respectively. Food and beverage, metallic and chemical/plastic industries were the biggest waste generators. Metallic industries with total score of 502.5 and non-metalic-mineral industries with the total score of 114 were categorised as the best and worst industries in terms of waste management practices.


Asunto(s)
Residuos Industriales , Administración de Residuos , Residuos Peligrosos , Irán , Reciclaje
9.
Ecotoxicol Environ Saf ; 168: 338-347, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30391838

RESUMEN

Exposure to nanoscale diesel engines exhausted particles (DEPs) is a well-recognized risk factor for respiratory and cardiovascular diseases. Rodents as commonly used models for urban air pollution in health effect studies demonstrate constant stimulation of inflammatory responses in the main areas of the brain. Nevertheless, the primary effect of diesel exhaust particulate matter on some of the brain regions and relation by behavioral alterations still remains untouched. We evaluated the brain regional inflammatory responses to a nanosized subfraction of diesel engines exhaust particulate matter (DEPs < 200 nm) in an adult male mice brain. Adult male mice were exposed to DEPs for 3, 6, and 8 h per day, 12 weeks and five days per week. Degree of anxiety and the depression by elevated plus maze and Forced Swimming Test respectively (FST) did measurement. After behavior tests, the plasma and some of the brain regions such as olfactory bulb (OB) and hippocampus (HI) were analyzed for oxidative stress and inflammatory responses. The inflammation and oxidative stress changes in OB and HI, markedly coincides with the results of behavioral alterations. These responses corresponded with rapid induction of MDA and nitrite oxide (NO) in brain regions and neuronal nitric oxide synthase (nNOS) mRNA followed by IL6, IL1α, and TNFα in OB and HI. The different times of DEPs exposure, leads to oxidative stress and inflammatory in plasma and brain regions. That this cumulative transport of inhaled nanoscale DEPs into the brain and creating to inflammation responses of brain regions may cause problems of brain function and anxiety and depression.


Asunto(s)
Ansiedad/inducido químicamente , Encéfalo/efectos de los fármacos , Depresión/inducido químicamente , Estrés Oxidativo , Emisiones de Vehículos/toxicidad , Animales , Ansiedad/fisiopatología , Biomarcadores/sangre , Encéfalo/fisiopatología , Depresión/fisiopatología , Masculino , Malondialdehído/sangre , Ratones , Nanopartículas/toxicidad , Óxido Nítrico/sangre , Tamaño de la Partícula , Material Particulado/toxicidad , Pruebas de Toxicidad Crónica
10.
J Environ Manage ; 186(Pt 1): 1-11, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27836562

RESUMEN

The photocatalytic degradation of organophosphorus pesticide such as diazinon was investigated by Cu-doped ZnO nanorods. Cu-doped ZnO nanorods were synthesized via a facile co-precipitation method. The catalyst was characterized by XRD, FESEM, EDX, VSM, XPS, and pHzpc techniques. The effects of some operational parameters such as solution pH, Cu-doped ZnO nanorods dosage, initial diazinon concentration, oxygen and nitrogen gases, H2O2 concentration, and type of organic compounds on the degradation efficiency were discussed through the photocatalytic experiments using the Cu-doped ZnO nanorods. Neutral pH was selected as an optimal pH condition due to a photo-corrosion of ZnO in acidic and basic conditions. As the Cu-doped ZnO nanorods dosage increased up to 0.2 g/L, degradation efficiency of diazinon was continuously enhanced. Pseudo-first-order rate constant (kobs) was decreased from 0.051 to 0.0052 min-1 and electrical energy per order (EEo) was increased from 94.12 to 923.08 (kWh/m3) by increasing diazinon concentration from 10 to 50 mg/L, respectively. The efficiency of the UV/Cu-doped ZnO for diazinon removal was approximately 96.97%, which was more effective than the UV/ZnO process (58.52%). Photocatalytic activity was maintained even after five successive cycles.


Asunto(s)
Cobre/química , Diazinón/química , Nanotubos/química , Óxido de Zinc/química , Catálisis , Precipitación Química , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Insecticidas/química , Cinética , Microscopía Electrónica de Rastreo , Procesos Fotoquímicos , Espectroscopía de Fotoelectrones , Soluciones/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
11.
Environ Monit Assess ; 189(8): 414, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28741247

RESUMEN

The presence of contaminants of emerging concern (CECs) such as pharmaceuticals and personal care products (PPCPs), endocrine-disrupting compounds (EDCs), flame retardants (FRs), pesticides, and artificial sweeteners (ASWs) in the aquatic environments remains a major challenge to the environment and human health. In this review, the classification and occurrence of emerging contaminants in aquatic environments were discussed in detail. It is well documented that CECs are susceptible to poor removal during the conventional wastewater treatment plants, which introduce them back to the environment ranging from nanogram per liter (e.g., carbamazepine) up to milligram per liter (e.g., acesulfame) concentration level. Meanwhile, a deep insight into the application of advanced oxidation processes (AOPs) on mitigation of the CECs from aquatic environment was presented. In this regard, the utilization of various treatment technologies based on AOPs including ozonation, Fenton processes, sonochemical, and TiO2 heterogeneous photocatalysis was reviewed. Additionally, some innovations (e.g., visible light heterogeneous photocatalysis, electro-Fenton) concerning the AOPs and the combined utilization of AOPs (e.g., sono-Fenton) were documented.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Carbamazepina , Disruptores Endocrinos/análisis , Retardadores de Llama/análisis , Humanos , Oxidación-Reducción , Plaguicidas/análisis , Aguas Residuales/química , Purificación del Agua/métodos
12.
Water Sci Technol ; 74(12): 2879-2888, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27997397

RESUMEN

In the current study, there are some considerable issues which focused on: (1) the production of biosurfactant, (2) its correlation with the initial bacterial inoculum in the liquid phase and (3) its effect on polycyclic hydrocarbon (PAH) bioremediation performance. Therefore, two strains Pseudomonas facilis and Pseudomonas spp. were able to form a large clear zone diameter on the oil surface. Phenanthrene (PHE) was also utilized as a sole substrate. Furthermore, biosurfactant production (BP) was detected by methylene blue analysis procedure and surface tension (ST) lowering. The capacity of these two strains to lower the aqueous ST was 29 and 30.7 from 72 mN m-1 by 6 days for P. facilis and Pseudomonas spp., respectively. Higher initial bacterial inoculation led to an improvement in PHE removal (P < 0.0001). But there was no significant correlation between either PHE solubility or BP and the initial bacterial inoculation. The removal efficiency of 88.44% within 21 days confirms that the inoculation of P. facilis led to the considerable BP for removal of PAHs from contaminated water.


Asunto(s)
Fenantrenos/aislamiento & purificación , Pseudomonas/metabolismo , Tensoactivos/metabolismo , Biodegradación Ambiental , Hidrocarburos Policíclicos Aromáticos , Solubilidad
13.
Environ Monit Assess ; 187(4): 168, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25750066

RESUMEN

In recent years, the growth of population and increase of the industries around the tributaries of Yamchi Dam basin have led to deterioration of dam water quality. This study aimed to evaluate the quality of the Yamchi Dam basin water, which is used for drinking and irrigation consumptions using Canadian Water Quality Index (CWQI) model, and to determine the main water pollution sources of this basin. Initially, nine sampling stations were selected in the sensitive locations of the mentioned basin's tributaries, and 12 physico-chemical parameters and 2 biological parameters were measured. The CWQI for drinking consumptions was under 40 at all the stations indicating a poor water quality for drinking consumptions. On the other hand, the CWQI was 62-100 for irrigation at different stations; thus, the water had an excellent to fair quality for irrigation consumptions. Almost in all the stations, the quality of irrigation and drinking water in cold season was better. Besides, for drinking use, total coliform and fecal coliform had the highest frequency of failure, and total coliform had the maximum deviation from the specified objective. For irrigation use, total suspended solids had the highest frequency of failure and deviation from the objective in most of the stations. The pisciculture center, aquaculture center, and the Nir City wastewater discharge were determined as the main pollution sources of the Yamchi Dam basin. Therefore, to improve the water quality in this important surface water resource, urban and industrial wastewater treatment prior to disposal and more stringent environmental legislations are recommended.


Asunto(s)
Monitoreo del Ambiente , Canadá , Ciudades , Ambiente , Irán , Modelos Teóricos , Estaciones del Año , Análisis Espacial , Aguas Residuales , Contaminación del Agua , Calidad del Agua/normas , Recursos Hídricos
14.
Int J Occup Environ Health ; 20(3): 258-63, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25000113

RESUMEN

BACKGROUND: The safe management of hospital waste is a challenge in many developing countries. OBJECTIVES: The aim of this study was to compare volatile organic compounds (VOCs) emissions and the microbial disinfectant safety in non-incineration waste disposal devices. METHODS: VOC emissions and microbial infections were measured in four non-incineration waste disposal devices including: autoclave with and without a shredder, dry heat system, and hydroclave. Using NIOSH and US EPA-TO14 guidelines, the concentration and potential risk of VOCs in emitted gases from four devices were assessed. ProSpore2 biological indicators were used to assess the microbial analysis of waste residue. RESULTS: There was a significant difference in the type and concentration of VOCs and microbial infection of residues in the four devices. Emissions from the autoclave with a shredder had the highest concentration of benzene, ethyl benzene, xylene, and BTEX, and emissions from the hydroclave had the highest concentration of toluene. The highest level of microbial infection was observed in the residues of the autoclave without a shredder. CONCLUSIONS: There is an increased need for proper regulation and control of non-incinerator devices and for monitoring and proper handling of these devices in developing countries.


Asunto(s)
Contaminantes Atmosféricos/análisis , Desinfección/métodos , Gases/análisis , Eliminación de Residuos Sanitarios/métodos , Compuestos Orgánicos Volátiles/análisis , Desinfección/instrumentación , Calor , Irán
15.
Sci Rep ; 14(1): 9308, 2024 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654035

RESUMEN

Over the recent years, ever-increasing population growth and higher wastewater production has been a challenge for decentralized wastewater treatment plants (WWTPs). In addition, sludge treatment due to high cost for equipment and place make authorities to find a sustainable approach in both of economical and technical perspectives. One of the proposed solutions is transferring the sludge produced from decentralized WWTP to centralized WWTP. However, the appropriate proportional ratio of raw sludge to raw sewage is a challenge, otherwise, it make anaerobic conditions and sewage rotting along the sewer network based on permissible limit of dihydrogen sulfide (H2S) gas (5 ppm). In the present study, seven reactors with different ratios of sludge to raw sewage (0, 15, 20, 25, 50, 75, 100) were used to stimulate the feasibility of transferring Shahrake Gharb WWTP sludge along the wastewater transfer pipe to the centralized sewage treatment south Tehran WWTP plant in Tehran, Iran. The septic situation and H2S emission of different reactors within 7 h (Time to reach the compound in the south treatment plant) was analyzed by gas meter. The results indicated that the optimum ratio of sludge to raw sewage was 15% without H2S production during 7 h. In addition, due to the high volume of sludge produced by the Shahrake Gharb WWTP, the optimal ratio of lime to total solids (TS) in sludge (gr/gr) (0.6) increased the sludge loading rate from 15 to 30% without any H2S emission during the stimulation study period. Therefore, the lime stabilization and transfer of sludge from a decentralized WWTP to a centralized WWTP is a feasible way to manage the sludge and enhance the treatment capacity in local WWTP.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales , Irán , Eliminación de Residuos Líquidos/métodos , Sulfuro de Hidrógeno/análisis , Estudios de Factibilidad , Reactores Biológicos
16.
Heliyon ; 10(6): e27862, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38560684

RESUMEN

All over the world, the level of special air pollutants that have the potential to cause diseases is increasing. Although the relationship between exposure to air pollutants and mortality has been proven, the health risk assessment and prediction of these pollutants have a therapeutic role in protecting public health, and need more research. The purpose of this research is to evaluate the ill-health caused by PM2.5 pollution using AirQ + software and to evaluate the different effects on PM2.5 with time series linear modeling by R software version 4.1.3 in the cities of Arak, Esfahan, Ahvaz, Tabriz, Shiraz, Karaj and Mashhad during 2019-2020. The pollutant hours, meteorology, population and mortality information were calculated by the Environmental Protection Organization, Meteorological Organization, Statistics Organization and Statistics and Information Technology Center of the Ministry of Health, Treatment and Medical Education for 24 h of PM2.5 pollution with Excel software. In addition, having 24 h of PM2.5 pollutants and meteorology is used to the effect of variables on PM2.5 concentration. The results showed that the highest and lowest number of deaths due to natural deaths, ischemic heart disease (IHD), lung cancer (LC), chronic obstructive pulmonary disease (COPD), acute lower respiratory infection (ALRI) and stroke in The effect of disease with PM2.5 pollutant in Ahvaz and Arak cities was 7.39-12.32%, 14.6-17.29%, 16.48-8.39%, 10.43-18.91%, 12.21-22.79% and 14.6-18.54 % respectively. Another result of this research was the high mortality of the disease compared to the mortality of the nose. The analysis of the results showed that by reducing the pollutants in the cities of Karaj and Shiraz, there is a significant reduction in mortality and linear modeling provides a suitable method for air management planning.

17.
Sci Rep ; 14(1): 10566, 2024 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719873

RESUMEN

Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe3O4@SiO2-NH2@CuO/ZnO core-shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV-Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O2- played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.


Asunto(s)
Amoxicilina , Antibacterianos , Luz , Nanoestructuras , Catálisis , Antibacterianos/química , Nanoestructuras/química , Amoxicilina/química , Contaminantes Químicos del Agua/química , Cobre/química , Óxido de Zinc/química , Dióxido de Silicio/química , Purificación del Agua/métodos
18.
Environ Sci Pollut Res Int ; 31(16): 23942-23950, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38436848

RESUMEN

Cigarette butt is a hazardous waste, and its management faces many challenges. The generation of leachate containing many pollutants including heavy metals is one of the limitations of recycling cigarette butts. The aim of this study was to reduce organic compounds and heavy metals in leachate resulting from cigarette butt recycling in an electrocoagulation reactor. For this purpose, two samples, including freshly smoked cigarette butts and littered cigarette butts, were processed and the treatment of leachate resulting from them was studied in an electrocoagulation reactor. The efficiency of leachate treatment was investigated in the treatment time of 10-40 min and current intensity of 20-100 mA. The results showed that the minimum reduction of chemical oxygen demand and turbidity was 25.3% and 33.4%, respectively. Increasing the current intensity and treatment time increased the efficiency of removing turbidity and chemical oxygen demand up to 47.1% and 41.2%, respectively, in optimum conditions. The reduction of nickel, chromium, cadmium, and lead in the lowest current density and minimum treatment time was more than 90%, which increased to more than 99% with the increase of the current density and treatment time. The use of electrocoagulation is a suitable solution to reduce heavy metals in leachate resulting from cigarette butt recycling, while the proper reduction of organic compounds in this type of leachate requires further treatment processes.


Asunto(s)
Metales Pesados , Productos de Tabaco , Carcinógenos , Productos de Tabaco/toxicidad , Reciclaje , Nicotiana
19.
Heliyon ; 10(11): e31640, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38845947

RESUMEN

Substances like asbestos and other air pollutants, such as BTEX (benzene, toluene, ethylbenzene, and xylene), are hazardous compounds due to their adverse effects on human health. This study aims to investigate the levels, seasonal variations, spatial distribution, potential sources, and associated health risks associated with BTEX compounds and asbestos fibers in the ambient air of Tabriz. Air samples were taken at 16 different locations during the 2020-2021 period. Glass containers with charcoal were used for sample collection, and the BTEX content was determined using the GC-FID method. Phase-contrast microscopy (PCM) analysis was conducted with a low-volume peripheral pump for asbestos fiber sampling. The results showed that the average concentration of ∑BTEX was 37.94 and 27.98 µg/m3 in autumn and spring, respectively. The same parameter was 2.26 and 1.68 f/L for asbestos in the autumn and winter, respectively. The contribution of BTEX to ozone formation potential (OFP) in the research area showed that xylene and toluene were the major contributors to ozone production in different seasons. The risk of exposure to benzene compounds was 24 × 10-4 in children and 55.9 × 10-4 in adults, while the risk of exposure to ethylbenzene was 3.78 × 10-4 in children and 3.25 × 10-4 in adults. The estimated lifetime cancer risk was found to be the highest for benzene, followed by ethylbenzene. The estimated cancer risk for benzene and ethylbenzene exceeded the threshold values set by EPA, which signals a significant carcinogenic risk due to exposure to these substances in the ambient air of Tabriz. According to the EPA guidelines, the low carcinogenicity risk levels are between 10-4 and 10-6. According to the findings for the exposure to asbestos fibers, the maximum values of excess cancer risk (ECR) and estimated lifetime cancer risk (ELCR) were observed in the 16-30 age range across all locations, suggesting increased exposure to asbestos fibers compared to other age groups.

20.
Heliyon ; 10(9): e30604, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38765134

RESUMEN

Residual pharmaceuticals in the environment are a class of emerging pollutants that endanger human health. Tetracycline's family, including oxytetracycline (OTC), are known as one of the most produced and consumed antibiotics worldwide. The g-C3N4/Fe3O4 nanocomposite with high level of catalytic efficiency features suitable performance in water/wastewater treatment. Therefore, in the present study, this nanocomposite was applied to remove the oxytetracycline from the aqueous environment. In this research study, g-C3N4/Fe3O4 nanocomposite (serving as catalyst) was initially synthesized by a simple hydrothermal method. The effect of key operating parameters such as initial solution pH, dose of catalyst, contact time and initial concentration of OTC in aqueous solutions was investigated under UV irradiation. In addition, COD and TOC tests, the kinetics and the effect of radical scavengers on the applied photocatalytic process were all evaluated. The maximum removal efficiency of OTC (99.8 %) was achieved under the following conditions: neutral solution pH 7; catalyst dose, 0.7 g/L; and an initial OTC concentration of 5 mg/L. The data showed that the kinetics of the reaction followed the first-order model with R2 of 0.9755. The respective COD and TOC efficiency values for the applied photocatalytic process were determined to be 87 and 59 %, respectively. In addition, the lowest removal efficiency of OTC was observed in the presence of tert-butanol radical scavengers, and OH radicals played a main role. The UV/g-C3N4/Fe3O4 photocatalytic process proved to be highly efficient for the removal of OTC antibiotic and could be potentially applied for the removal of other pollutants from aqueous solutions.

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