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1.
Environ Res ; 229: 115843, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37068722

RESUMO

Wastewater treatment using bioelectrochemical systems (BESs) can be considered as a technology finding application in versatile areas such as for renewable energy production and simultaneous reducing environmental problems, biosensors, and bioelectrosynthesis. This review paper reports and critically discusses the challenges, and advances in bio-electrochemical studies in the 21st century. To sum and critically analyze the strides of the last 20+ years on the topic, this study first provides a comprehensive analysis on the structure, performance, and application of BESs, which include Microbial Fuel Cells (MFCs), Microbial Electrolysis Cells (MECs) and Microbial Desalination Cells (MDCs). We focus on the effect of various parameters, such as electroactive microbial community structure, electrode material, configuration of bioreactors, anode unit volume, membrane type, initial COD, co-substrates and the nature of the input wastewater in treatment process and the amount of energy and fuel production, with the purpose of showcasing the modes of operation as a guide for future studies. The results of this review show that the BES have great potential in reducing environmental pollution, purifying saltwater, and producing energy and fuel. At a larger scale, it aspires to facilitate the path of achieving sustainable development and practical application of BES in real-world scenarios.


Assuntos
Fontes de Energia Bioelétrica , Reatores Biológicos , Eletrólise , Tecnologia
2.
Ecotoxicol Environ Saf ; 263: 115229, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37441953

RESUMO

Cantaloupe is a popular agricultural product in the hot season of Iran. On the other hand, the frequent use of pesticides in cantaloupe fields is the most important threat to the health of farmers and consumers. Therefore, the present study aims to measure the concentration of diazinon (DZN), chlorpyrifos (CPF), and malathion (MLT) in cantaloupe cultivated in Kashan and Aran-Bidgol (Iran) and to estimate the possible oral and dermal risk of these pesticides by Monte Carlo simulation (MCS). 36 cantaloupe samples, 18 samples before, and 18 samples after the latent period were collected from different places of cantaloupe cultivation from April to May 2021. After measuring the pesticides using the QuEChERS approach, oral and dermal risk assessments were calculated.The mean and standard deviation of the concentrations of chlorpyrifos, malathion, and diazinon in 18 cantaloupe samples, after the latent period, were (30.39 ± 13.85), (18.361 ± 1.8), and (21.97 ± 0.86) µg kg-1, respectively. Concentration of Malathion, diazinon, and Chlorpyrifos in the soil were 0.22, 0.25, and 0.3 mg kg-1, respectively, and pesticide cumulative risk assessment in soil was obtained 0.011 for Malathion, 0.05 for diazinon and 0.03 for Chlorpyrifos. Target Hazard Quotient (THQ) according to the cantaloupe consumption and dermal exposure in children and adults, was safe range. Although non-cancerous dermal and oral risk of cantaloupe is low, constant exposure can be harmful. Therefore, the findings of this study play an important role in increasing the understanding of the negative health consequences of pesticide contamination in cantaloupe for consumers, especially local residents, and can help by adopting remedial strategies to reduce environmental concerns.


Assuntos
Clorpirifos , Cucumis melo , Resíduos de Praguicidas , Praguicidas , Adulto , Criança , Humanos , Resíduos de Praguicidas/análise , Clorpirifos/análise , Diazinon , Malation , Solo , Irã (Geográfico) , Método de Monte Carlo , Praguicidas/análise , Medição de Risco
3.
J Environ Manage ; 326(Pt A): 116584, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36403318

RESUMO

In this study, the photocatalytic activity of ZnO was effectively improved via its combination with spinel cobalt ferrite (SCF) nanoparticles. The catalytic performance of ZnO@SCF (ZSCF) was investigated in coupling with UV irradiation and ultrasound (US), as a heterogeneous sono-photocatalytic process, for the decontamination of phenanthrene (PHE) from contaminated soil. Soil washing tests were conducted in a batch environment, after extraction assisted by using Tween 80. Several characterization techniques such as XRD, FESEM-EDS, BET, TEM, UV-vis DRS, PL and VSM were utilized to determine the features of the as-prepared catalysts. ZSCF showed an excellent catalytic activity toward degradation of PHE in the presence of US and UV with a significant synergic effect. It was found that more than 93% of PHE (35 mg/L) and 87.5% of TOC could be eliminated by the integrated ZSCF/US/UV system under optimum operational conditions (pH: 8.0, ZSCF: 1.5 g/L, UV power: 6.0 W and US power: 70 W) within 90 min of reaction. After five times of use, ZSCF illustrated good reusability in the decontamination of PHE (87%) and TOC (79%). Quenching tests revealed the contribution of h+, HO• and e- species during PHE degradation over ZSCF/UV/US and an S-scheme photocatalytic mechanisms was proposed for the possible charge transfer routes under the ZSCF system. This study provides the important role of SCF in enhancing the ZnO photocatalytic activity due to its high performance, easy recovery and excellent durability, which it make an efficient and promising catalyst in environmental clean-up applications.


Assuntos
Tensoativos , Óxido de Zinco , Solo
4.
J Environ Manage ; 342: 118242, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295145

RESUMO

Developing heterogeneous catalysts with high performance for peroxymonosulfate (PMS) activation to decontaminate organic pollutants from wastewater is of prominent importance. In this study, spinel cobalt ferrite (CoFe2O4) materials were coated on the surface of powdered activated carbon (CoFe2O4@PAC) via the facile co-precipitation method. The high specific surface area of PAC was beneficial for the adsorption of both bisphenol A (BP-A) and PMS molecules. The CoFe2O4@PAC-mediated PMS activation process under UV light could effectively eliminate 99.4% of the BP-A within 60 min of reaction. A significant synergy effect was attained between CoFe2O4 and PAC towards PMS activation and subsequent elimination of BP-A. Comparative tests demonstrated that the heterogeneous CoFe2O4@PAC catalyst had a better degradation performance in comparison with its components and homogeneous catalysts (Fe, Co, and, Fe + Co ions). The formed by-products and intermediates during BP-A decontamination were evaluated using LC/MS analysis, and then a possible degradation pathway was proposed. Moreover, the prepared catalyst exhibited excellent performance in recyclability with slight leaching amounts of Co and Fe ions. A TOC conversion of 38% was obtained after five consecutive reaction cycles. It can be concluded that the PMS photo-activation process via the CoFe2O4@PAC catalyst can be utilized as an effective and promising method for the degradation of organic contaminants from polluted-water resources.


Assuntos
Carvão Vegetal , Raios Ultravioleta , Porosidade , Peróxidos , Cobalto
5.
Waste Manag Res ; 41(2): 368-375, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35959868

RESUMO

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.


Assuntos
Monitoramento Ambiental , Produtos do Tabaco , Poluição Ambiental , Resíduos , Plásticos , Praias
6.
Med J Islam Repub Iran ; 32: 76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30643751

RESUMO

Background: Air pollution is one of the main reasons for disease and emergency hospitalizations. Therefore, air pollution control and hospital preparedness are of paramount importance. This study was conducted to determine the association of air pollutant levels with the rate of hospital emergency admissions due to respiratory and cardiovascular diseases and acute myocardial infarction in Tehran during the last decade. Methods: This was a cross sectional study. At first, information on hourly concentration of air pollutants was gathered from Tehran Environmental Protection Agency and Air Quality Control Company. Raw data and meteorological parameters were used in Excel format to prepare an input file. The number of emergency hospital admissions due to pollutant exposure was assessed using the AirQ2.2.3 model. Results: Results of this study revealed that there were 54 352 cases of emergency hospitalizations due to respiratory diseases in a relative risk of 1.0048 [1.0008-1.0112] and 20 990 cases of emergency hospitalizations due to cardiovascular diseases in a relative risk of 1.009[1.006-1.013] during 2005-2014. In addition, 3478 patients were admitted to the emergency department because of acute myocardial infarction with RR of 1.0026 [1.0026-1.0101]. Conclusion: This study demonstrated that a high percentage of hospital emergency admissions was because of respiratory and cardiovascular diseases. Moreover, it was found that acute myocardial infarction could be due to the high level of air pollution and could increase admissions to the emergency department. Therefore, appropriate measures are needed to reduce air pollution and increase hospital preparedness.

7.
Environ Monit Assess ; 189(8): 414, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28741247

RESUMO

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.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Carbamazepina , Disruptores Endócrinos/análise , Retardadores de Chama/análise , Humanos , Oxirredução , Praguicidas/análise , Águas Residuárias/química , Purificação da Água/métodos
8.
Water Sci Technol ; 74(12): 2879-2888, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27997397

RESUMO

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.


Assuntos
Fenantrenos/isolamento & purificação , Pseudomonas/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Solubilidade
9.
Water Sci Technol ; 69(1): 147-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24434981

RESUMO

In the present study, powder activated carbon (PAC) combined with Fe(3)O(4) magnetite nanoparticles (MNPs) were used for the preparation of magnetic composites (MNPs-PAC), which was used as an adsorbent for amoxicillin (AMX) removal. The properties of magnetic activated carbon were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Brunaeur, Emmett and Teller and vibrating sample magnetometer. The operational factors affecting adsorption such as pH, contact time, adsorbent dosage, initial AMX concentration and temperature were studied in detail. The high surface area and saturation magnetization for the synthesized adsorbent were found to be 671.2 m(2)/g and 6.94 emu/g, respectively. The equilibrium time of the adsorption process was 90 min. Studies of adsorption equilibrium and kinetic models revealed that the adsorption of AMX onto MNPs-PAC followed Freundlich and Langmuir isotherms and pseudo-second-order kinetic models. The calculated values of the thermodynamic parameters, such as ΔG°, ΔH° and ΔS° demonstrated that the AMX adsorption was endothermic and spontaneous in nature. It could be concluded that MNPs-PAC have a great potential for antibiotic removal from aquatic media.


Assuntos
Amoxicilina/química , Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Purificação da Água/métodos
10.
Heliyon ; 10(9): e30604, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765134

RESUMO

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.

11.
Chemosphere ; 358: 142102, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677611

RESUMO

A heterogeneous catalyst was prepared by anchoring spinel cobalt ferrite nanoparticles on porous activated carbon (SCF@AC). The catalyst was tested to activate hydrogen peroxide (HP) in the Fenton degradation of metronidazole (MTZ). SCF nanoparticles were produced through the co-precipitation of iron and cobalt metal salts in an alkaline condition. Elemental mapping, physico-chemical, morphological, structural, and magnetic properties of the as-fabricated catalyst were analyzed utilizing EDX mapping, FESEM-EDS, TEM, BET, XRD, and VSM techniques. The porous structure of AC enhanced the catalytic activity of SCF by a significant decrease in the agglomeration of SCF nanoparticles. The effectiveness of SCF@AC in Fenton degradation improved substantially when UV light and ultrasound (US) irradiations were induced, most likely due to the strong synergistic effect between the catalyst and these irradiation sources. The photo-Fenton system was more efficient than the Fenton, sono-, and sono-photo-Fenton processes eliminating both MTZ and TOC. It was found that AC not only dispersed SCF nanoparticles and improved the stability of the catalyst, but also provided a high adsorption capacity of MTZ, resulting in a faster degradation. After 60 min of the photo-Fenton reaction, the elimination efficiencies of MTZ (30 mg L-1) and TOC were 97 and 42.1% under optimum operational conditions (pH = 3.0, HP = 4.0 mM, SCF@AC = 0.3 g L-1, and UV = 6 W). SCF@AC showed excellent stability with low leaching of metal ions during the reaction. Radical and non-radical (O2•-, HO•, and 1O2 species), alongside adsorption and photocatalysis mechanisms, were responsible for MTZ decontamination over the SCF@AC/HP/UV system. A comprehensive study on the HP activation mechanism and MTZ degradation pathway was obtained through scavenging tests. The findings demonstrate that SCF@AC is an effective, reusable, and environmentally sustainable catalyst for advanced oxidation processes that can effectively remove organic pollutants from wastewater. This study offers valuable insights into the feasibility of employing SCF@AC catalysts in Fenton-based processes for the degradation of MTZ.


Assuntos
Carvão Vegetal , Cobalto , Compostos Férricos , Peróxido de Hidrogênio , Ferro , Metronidazol , Poluentes Químicos da Água , Cobalto/química , Catálise , Peróxido de Hidrogênio/química , Compostos Férricos/química , Ferro/química , Metronidazol/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Adsorção , Raios Ultravioleta
12.
Sci Rep ; 14(1): 12417, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816573

RESUMO

We conducted a hospital-based case-control study to explore the association between proximity to various land use types and childhood leukemia and lymphoma. This research involved 428 cases of childhood leukemia and lymphoma (2016-2021), along with a control group of 428 children aged 1-15 in Tehran. We analyzed the risk of childhood cancer associated with land use by employing logistic regression adjusted for confounding factors such as parental smoking and family history. The odds ratio (OR) for children with leukemia and lymphoma residing within 100 m of the nearest highway was 1.87 (95% CI = 1.00-3.49) and 1.71 (95% CI = 1.00-2.93), respectively, in comparison to those living at a distance of 1000 m or more from a highway. The OR for leukemia with exposure to petrol stations within 100 m was 2.15 (95% CI = 1.00-4.63), and for lymphoma it was 1.09 (95% CI = 0.47-2.50). A significant association was observed near power lines (OR = 3.05; 95% CI = 0.97-9.55) within < 100 m for leukemia. However, no significant association was observed between power lines and the incidence of childhood lymphoma. There was no association between bus stations, major road class 2, and the incidence of childhood leukemia and lymphoma. In conclusion, our results suggest a possible association between the incidence of childhood leukemia and proximity to different urban land uses (i.e., highways and petrol stations). This study is the first step in understanding how urban land use affects childhood leukemia and lymphoma in Tehran. However, comprehensive studies considering individual-level data and specific pollutants are essential for a more nuanced understanding of these associations.


Assuntos
Leucemia , Linfoma , Humanos , Criança , Irã (Geográfico)/epidemiologia , Masculino , Leucemia/epidemiologia , Leucemia/etiologia , Feminino , Linfoma/epidemiologia , Linfoma/etiologia , Linfoma/induzido quimicamente , Pré-Escolar , Adolescente , Estudos de Casos e Controles , Lactente , Exposição Ambiental/efeitos adversos , Fatores de Risco , Razão de Chances , Incidência
13.
Sci Rep ; 13(1): 21829, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071282

RESUMO

Environmental destruction, water crisis, and clean energy are among the very important challenges worldwide based on sustainable development goals. Photocatalytic fuel cell, a potential candidate for converting chemical energy into electrical energy through a pollution-free method, holds promise in addressing these challenges. In this regard, we investigated the response of a photoanode covered with UiO66-NH2-TiO2/NiF on a porous nickel foam as an attractive electrochemical response to remove antibiotics from aqueous solution and simultaneously produce electricity using a one-step hydrothermal synthesis. Nickel foam with its fine structure provides a suitable space for the interaction of light, catalyst, and efficient mass transfer of reactive molecules. It appears that it can be used as a competitive electrode in fuel cells. In order to investigate the properties of the photocatalyst, structural analyses including XRD, FESEM, FTIR, and UV-vis DRS were utilized. Additionally, polarization and electrochemical tests such as chronoamperometry and EIS were measured to further examine the electrochemical features of the PFC photoanode system. The obtained results under optimal conditions (SMZ concentration = 20 ppm, pH = 6, irradiation time = 120 min) were as follows: removal efficiency of 91.7%, Pmax = 16.98 µW/cm2, Jsc = 96.75 µA/cm2, Voc = 644 mV. The light-induced current flow in UiO66-NH2-TiO2/NiF exhibited prominent and reproducible photocurrent responses, indicating efficient and stable charge separation in TiO2/NiF composite materials, which is a promising strategy for pollutant removal and simultaneous electricity generation.

14.
Environ Sci Pollut Res Int ; 30(2): 5126-5136, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35974284

RESUMO

Persistent organic pollutants, such as polycyclic aromatic hydrocarbons, are hazardous trace contaminants frequently observed in food ingredients, such as edible oils. This study aimed to measure PAHs in forty brands of edible oils marketed in southwest Iran. Additionally, we characterized the daily intake of MOE and ILCR using Monte Carlo simulation. To analyze the content of PAHs, the liquid-liquid extraction method followed by GC-MS was utilized. The average concentration of PAHs was mostly lower than the maximum value for individual PAH (2 µg/Kg); however, the average concentration of fluorene (3.86 µg/Kg) and benzo(a)anthracene (3.13 µg/Kg) was more than the permitted level. The highest residual concentrations of PAHs were mostly observed in canola and corn oils. The daily intake of BaP and 4-PAH for 95% of consumers was 0.01 ng/kg BW/day and 0.04 ng/kg BW/day, respectively. Also, MOE was more than 10,000 for the percentiles of 5%, 50%, and 95%. The modeled ILCR showed that consumption of oil does not currently pose a cancer risk for Iranian consumers due to PAHs exposure. Concerning potential health risks, consumption of edible oils is safe; however, regular monitoring and assessment are required.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Irã (Geográfico) , Hidrocarbonetos Policíclicos Aromáticos/análise , Método de Monte Carlo , Óleos de Plantas , Alimentos , Medição de Risco
15.
Waste Manag Res ; 30(9): 883-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22446973

RESUMO

Landfill leachates contain a wide variety of pollutants such as organic matter, refractory compounds, ammonia, particulate and dissolved solids and hazardous metals requiring application of advanced and well designed treatment processes before release to the environment. The main purpose of this research was to evaluate the efficiency of combined air stripping, Fenton oxidation and biological treatment in treating landfill leachate, especially the elimination of ammonia and refractory organics. The laboratory scale set-up consisted of three sequential but separate steps. The optimum conditions for air stripping and the Fenton oxidation were determined for landfill leachate from Karaj city, Iran. The final step was a moving bed bioreactor with HRTs of 18, 12 and 6 h. The highest NH(3)-N removal was 79% in the air stripping process at pH 10.5. At the optimum conditions for the Fenton reaction at a reaction time of 90 min, pH 3 and a H(2)O(2)/Fe(2+) mass ratio of 20, the COD removal was 61% and improved the BOD/COD ratio from 0.42 to 0.78. The overall COD removal including the final biological reactor with a HRT of 6 h resulted in an effluent COD concentration of less than 100 mg L(-1).


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Eliminação de Resíduos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Amônia/química , Reatores Biológicos , Irã (Geográfico) , Oxirredução , Estações do Ano
16.
Environ Sci Pollut Res Int ; 29(37): 56403-56418, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35334054

RESUMO

In this study photo-catalytic degradation of sulfamethoxazole (SMX) from aqueous solutions using carbon quantum dot (CQD)-decorated Cu-TiO2 was investigated. The as-prepared photo-catalyst samples were characterized by various FTIR, XRD, FE-SEM, TEM, EDX, BET, and DRS techniques. The investigation of effective photo-catalytic operational parameters confirmed that the complete removal of SMX (20 mg/L) can be accomplished at pH: 6.0 and light intensity: 75 mW/cm2 over a 30-min reaction time. DRS analysis demonstrated adding CQD to the Cu-TiO2 reduced its bandgap energy from 2.97 to 2.90 eV. The photo-catalytic degradation kinetics of SMX fit well with the pseudo-first-order model. The radical trapping experiment indicates that HO• and O2•- active species were more effective species for SMX degradation, and the higher inhibition effect on the SMX degradation efficiency was assigned to O2•- ions. The water matrix species-inhibited effect in SMX removal was as follows: SO42- > Cl- > NO3- > CO3- > no ions. The synthesized photo-catalyst could be recycled after six consecutive cycles of SMX degradation with an insignificant decrease in performance. The total organic carbon (TOC) analysis suggested the mineralization of SMZ by composite photo-catalysts. The minimum inhibitory concentration (MIC) for Escherichia coli remained at 12.5 mg L-1 SMX. A possible mechanism and pathway of SMX degradation in the photo-catalytic system was presented.


Assuntos
Sulfametoxazol/metabolismo , Titânio/química , Águas Residuárias/química , Poluentes Químicos da Água , Carbono , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Preparações Farmacêuticas
17.
Chemosphere ; 286(Pt 1): 131667, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34325256

RESUMO

Excessive application of pesticides to control pests and weeds leads to contaminating bodies of water and health problems for consumers. The present study was designed to investigate the concentration of pesticides in raw water originated from the Marun River as well as the treated water of the drinking water treatment plant in Behbahan City. The efficiency of each treatment process was evaluated. Moreover, the health risks caused by detectable pesticides for consumers of treated water were assessed. The target pollutants were extracted using droplet liquid-liquid microextraction and detected by a gas chromatograph-mass spectrophotometer. The results showed relatively high mean concentrations of organophosphate pesticides ranging from 0.87 to 3.229 µg/L in the river water and low concentrations of organochlorine pesticides, except for 1,3-dichloropropene with the concentration of 3.58 µg/L. Alachlor had a rather high concentration (2.44 µg/L) in the river water. The concentration of pesticides in the drinking water had been reduced to an acceptable amount. The major part of pesticides removal occurred in coagulation-flocculation and rapid sand filtration units (87 %) due to the hydrophobic nature of pesticides and the use of GAC in the filtration unit. Based on the risk assessment estimates, the total hazard quotient (THQ) for all the pesticides was much less than one. The value of THQ was higher in younger individuals and children for all the given pesticides. The highest value of THQ in children was 0.2 which was attributed to aldrin. Similarly, the carcinogenic risk (CR) of aldrin for children and teenagers was in the unsafe range (more than 10-4) while the CR for other target compounds in all the age groups was negligible (10-4-10-6 or less). The high concentration of pesticides in the river water might be concerning and therefore selling and using pesticides, especially the banned ones, should be more regulated.


Assuntos
Água Potável , Praguicidas , Poluentes Químicos da Água , Adolescente , Criança , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Método de Monte Carlo , Praguicidas/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise
18.
J Environ Health Sci Eng ; 20(1): 101-112, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35669829

RESUMO

The present study, magnetically separable Fe2O3@ZnO/CQD nanocomposite was successfully prepared via hydrothermal process and characterized with SEM-EDX, XRD, FTIR, VSM and DRS analysis. The effect of operational parameters includes photocatalyst dosage, photocatalyst type, CQD content and Escherichia coli (E. coli) concentration were evaluated on the E. coli inactivation. The disinfecting ability of nanocomposite components was obtained as Fe2O3@ZnO/CQD> Fe2O3@ZnO> ZnO> Fe2O3> CQD which shows a synergetic effect among different components. The highest E. coli inactivation rate (Kmax=0.7606 min-1) was obtained at photocatalyst dosage of 0.2 g/L and 15% CQD content. The MIC and MBC values value for E. coli were determined 0.1172 mg/mL and 0.4948 respectively that the results tests proved the antibacterial functions of the Fe2O3@ZnO/CQD. Nanocomposite showed the high reusability after 4 consecutive cycles, Kmax decreased from 0.7606 min-1 to 0.6181 min-1. Quenching experiments showed •OH and h+ are the main reactive oxygen species involved in the E. coli inactivation.

19.
Rev Environ Health ; 37(4): 597-612, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34700370

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are organic pollutants containing several hydrocarbon rings affecting human health according to the published monitoring data. Most of these compounds can be absorbed by the soil and sediments due to the abundance of production resources of these compounds in the soil around the cities and sediments of the Iranian coast. Cancer risk assessment (CRA) is one of the most effective methods for quantifying the potentially harmful effects of PAHs on human health. In this study, the published papers that monitored PAHs in Iran's soil and sediments were reviewed. The extraction of different data and their equivalent factors were performed according to BaP equivalent, which is the main factor for calculating CRA of PAHs. The highest concentrations of PAHs were found in the sediments of Assaluyeh industrial zones (14,844 µg/kg), Khormousi region (1874.7 µg/kg), and Shadegan wetland (1749.5 µg/kg), respectively. Dermal exposure to sediments was 96% in adults, and 4% in children, and ingestion exposure to sediment was 99% in adults and 99.2% in children. Children dermal exposure to soil was 53%, and the accidental exposure to soil was 47%. In adults, dermal exposure to soil was 96% and the accidental exposure was 4%. The results of the present study indicated a significant, the carcinogenic risk of Polycyclic Aromatic Hydrocarbons in sediments of southern regions and soils of central regions of Iran is significant.


Assuntos
Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Adulto , Criança , Humanos , Solo , Irã (Geográfico)/epidemiologia , Poluentes do Solo/efeitos adversos , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Medição de Risco , Sedimentos Geológicos , China
20.
Sci Rep ; 12(1): 20336, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434119

RESUMO

This study investigated the recycling of freshly-smoked cigarette butts (FCBs) and unsmoked cigarette filters (UCFs) into a cellulose acetate (CA) membrane. The both samples were prepared by means of a combination of seven cigarette brands, and the phase inversion method was used to recycle each sample into a membrane using N-methyl-2-pyrrolidone. The efficiency of the prepared membranes for the removal of chromium, cadmium, and lead from an aqueous solution in a forward osmosis reactor was investigated. The results showed that the both membranes had a smooth surface and macrovoids. The flux of the prepared membranes from the UCFs and FCBs recycling were 14.8 and 13.2 LMH, respectively. The porosity and reverse salt of the UCFs membrane were 61% and 3.5 gMH, while those for FCBs membrane were 58% and 3.9 gMH. The observed metal removal efficiency of the both membranes was in the range of 85 to 90%. However, increasing the concentration of metals up to five times caused a slight decrease in the removal efficiency (less than 5%).


Assuntos
Metais Pesados , Produtos do Tabaco , Membranas Artificiais , Celulose , Água , Fumaça
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