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1.
Sci Rep ; 14(1): 10566, 2024 05 08.
Article in English | MEDLINE | ID: mdl-38719873

ABSTRACT

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.


Subject(s)
Amoxicillin , Anti-Bacterial Agents , Light , Nanostructures , Catalysis , Anti-Bacterial Agents/chemistry , Nanostructures/chemistry , Amoxicillin/chemistry , Water Pollutants, Chemical/chemistry , Copper/chemistry , Zinc Oxide/chemistry , Silicon Dioxide/chemistry , Water Purification/methods
2.
Ecotoxicol Environ Saf ; 277: 116369, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38678793

ABSTRACT

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.


Subject(s)
Biodegradation, Environmental , Enzymes , Enzymes/metabolism , Wastewater/chemistry , Garbage , Composting , Sewage/microbiology , Fermentation
3.
Int J Biol Macromol ; 267(Pt 2): 131481, 2024 May.
Article in English | MEDLINE | ID: mdl-38599431

ABSTRACT

We developed an effective and eco-friendly strategy using chitosan gel-molten salt to achieve high loading (2.23 At. %) of single Fe-NX as assistive active sites. These sites were combined with small NiCo alloy NPs distributed on porous carbon aerogels to boost the ORR performance. The FeSAs-NiCo alloy@N-C sphere exhibits exceptional mass activity and specific activity of 3.705 A.mg-1 and 8.79 mA.cm-2(ECSA), respectively, at 0.85 V versus RHE. It has a superior onset potential of 1.08 V versus RHE, surpassing that of its nanoparticle Fe counterpart and NiCo alloy@N-C sphere. The significant improvement in ORR performance of the FeSAs-NiCo alloy@N-C sphere could be attributed to the positive effects of increased lattice strain due to the single atoms of Fe-NX hybridized with small NiCo alloy NPs. The chitosan gel-assisted molten salt strategy and assistive active sites of Fe-NX hybridized with NiCo alloy NPs regulate the electronic properties of the FeSAs-NiCo alloy@N-C sphere, both geometrically via lattice strain mismatch and electronically through shifting of the d-band center. This could influence the binding energies for oxygen and/or oxygen reduction intermediate adsorption/desorption. The additional improvement in the ORR performance of the FeSAs-NiCo alloy@N-C sphere also benefits from having a lower electrochemical activation energy.


Subject(s)
Alloys , Chitosan , Gels , Oxidation-Reduction , Oxygen , Chitosan/chemistry , Oxygen/chemistry , Alloys/chemistry , Gels/chemistry , Iron/chemistry , Metal Nanoparticles/chemistry , Nickel/chemistry , Cobalt/chemistry , Catalysis , Salts/chemistry
4.
Heliyon ; 10(6): e27862, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38560684

ABSTRACT

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.

5.
Sci Rep ; 14(1): 9308, 2024 04 23.
Article in English | MEDLINE | ID: mdl-38654035

ABSTRACT

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.


Subject(s)
Sewage , Waste Disposal, Fluid , Wastewater , Iran , Waste Disposal, Fluid/methods , Hydrogen Sulfide/analysis , Feasibility Studies , Bioreactors
7.
Toxicol Rep ; 12: 56-64, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38261924

ABSTRACT

In big and industrial cities of developing countries, illness and mortality from long-term exposure to air pollutants have become a serious issue. This research was carried out in 2019-2020 to estimate the health impacts of PM10, NO2 and O3 pollutants by using AirQ+ and R statistical programming software in Arak, Isfahan, Tabriz, Shiraz, Karaj, and Mashhad. Mortality statistics, number of people in required age groups, and amount of pollutants were gathered respectively from different agencies like Statistics and Information Technology of the Ministry of Health, Statistical Center, and Department of Environment and by using Excel, the average 24-hour and 1-hour concentration and maximum 8-hour concentration for PM10, NO2 and O3 pollutants were gathered. We used linear mixed impacts model to account for the longitudinal observations and heterogeneity of the cities. The results of the study showed high number of deaths due to chronic bronchitis in adults, premature death of infants, and respiratory diseases in Mashhad. This research highlights the importance of estimation of health impacts from exposure to air pollutants on residents of the studied cities.

8.
Sci Rep ; 14(1): 1083, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38212370

ABSTRACT

Styrene is a volatile organic compound with various applications, especially in the plastics and paint industries. Exposure to it leads to symptoms such as weakness, suppression of the central nervous system, and nausea, and prolonged exposure to it increases the risk of cancer. Its removal from the air is a topic that researchers have considered. Various methods such as absorption, membrane separation, thermal and catalytic oxidation, biofiltration have been used to remove these compounds. The disadvantages of these compounds include the need for high energy, production of secondary pollutants, large space, providing environmental conditions (temperature and humidity) and long time. The photocatalyst process is considered as an advanced process due to the production of low and safe secondary pollutants. MOFs are nanoparticles with unique photocatalytic properties that convert organic pollutants into water and carbon dioxide under light irradiation and in environmental conditions, which prevent the production of secondary pollutants. The present study aimed to investigate the efficiency of MIL100 (Fe) nanoparticles coated on glass in removing styrene vapor from the air. Surface morphology, crystal structure, pore size, functional groups, and chemical composition of the catalyst were analyzed by SEM, XRD, BET, FTIR, and EDX analysis. The effect of parameters such as initial pollutant concentration, temperature, time, relative humidity, and nanoparticle concentration was evaluated as effective parameters in the removal process. Based on the results, MIL100 (Fe) 0.6 g/l with an 89% removal rate had the best performance for styrene removal. Due to its optimal removal efficiency, it can be used to degrade other air pollutants.

9.
Chemosphere ; 349: 140972, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38114023

ABSTRACT

Pharmaceutical substances in the ecosystem pose a notable hazard to human and aquatic organism well-being. The occurrence of ciprofloxacin (CIP) within water sources or the food chain can perturb plant biochemical processes and induce drug resistance in both humans and animals. Therefore, effective removal is imperative prior to environmental discharge. This study introduces a Novel Carbohydrate-Based Nanocomposite (Fe3O4/MOF/AmCs-Alg) as a proficient photocatalytic agent for degrading CIP in aqueous solutions. The fabricated nanocomposite underwent characterization using FTIR, XRD, FESEM, DRS, and VSM techniques. The analyses conducted verified the successful synthesis of the Fe3O4/MOF/AmCs-Alg nanocomposite. Utilizing the optimized parameters (pH = 5, nanocomposite dose = 0.4 g/L, CIP concentration = 10 mg/L, light intensity = 75 mW/cm2, and a duration of 45min), the Fe3O4/MOF/AmCs-Alg/Vis nanocomposite demonstrated an impressive CIP degradation efficiency of 95.85%. Under optimal experiment conditions, CIP removal efficiency in tap water and treated wastewater samples was 91.27% and 76.78%, respectively. Furthermore, the total organic carbon (TOC) analysis indicated a mineralization rate of 51.21% for CIP. Trapping studies demonstrated that the superoxide radical (O2°-) had a notable contribution to the breakdown of CIP. In summary, the Fe3O4/MOF/AmCs-Alg/Vis system offers numerous benefits, encompassing effective degradation capabilities, effortless catalyst retrieval, and remarkable nanocomposite reusability.


Subject(s)
Ciprofloxacin , Nanocomposites , Humans , Ciprofloxacin/chemistry , Ecosystem , Water/chemistry , Light , Nanocomposites/chemistry , Catalysis
10.
Environ Geochem Health ; 46(1): 20, 2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38153542

ABSTRACT

According to epidemiological studies, particulate matter (PM) is an important air pollutant that poses a significant threat to human health. The relationship between particulate matter and respiratory diseases has been the subject of numerous studies, but these studies have produced inconsistent findings. The purpose of this systematic review was to examine the connection between outdoor particulate matter (PM2.5 and PM10) exposure and respiratory disorders (COPD, lung cancer, LRIs, and COVID-19). For this purpose, we conducted a literature search between 2012 and 2022 in PubMed, Web of Science, and Scopus. Out of the 58 studies that were part of the systematic review, meta-analyses were conducted on 53 of them. A random effect model was applied separately for each category of study design to assess the pooled association between exposure to PM2.5 and PM10 and respiratory diseases. Based on time-series and cohort studies, which are the priorities of the strength of evidence, a significant relationship between the risk of respiratory diseases (COPD, lung cancer, and COVID-19) was observed (COPD: pooled HR = 1.032, 95% CI: 1.004-1.061; lung cancer: pooled HR = 1.017, 95% CI: 1.015-1.020; and COVID-19: pooled RR = 1.004, 95% CI: 1.002-1.006 per 1 µg/m3 increase in PM2.5). Also, a significant relationship was observed between PM10 and respiratory diseases (COPD, LRIs, and COVID-19) based on time-series and cohort studies. Although the number of studies in this field is limited, which requires more investigations, it can be concluded that outdoor particulate matter can increase the risk of respiratory diseases.


Subject(s)
COVID-19 , Lung Neoplasms , Pulmonary Disease, Chronic Obstructive , Respiration Disorders , Respiratory Tract Diseases , Humans , Particulate Matter/toxicity , Respiratory Tract Diseases/chemically induced , Respiratory Tract Diseases/epidemiology , COVID-19/epidemiology , Pulmonary Disease, Chronic Obstructive/chemically induced , Pulmonary Disease, Chronic Obstructive/epidemiology
11.
Sci Rep ; 13(1): 17858, 2023 10 19.
Article in English | MEDLINE | ID: mdl-37857811

ABSTRACT

Exposure to particulate matter (PM) can be considered as a factor affecting human health. The aim of this study was to investigate the concentration of PM2.5 and heavy metals and their influence on survival of A549 human lung cells in exposure to PM2.5 breathing air of Ahvaz city. In order to assess the levels of PM2.5 and heavy metals, air samples were collected from 14 sampling stations positioned across Ahvaz city during both winter and summer seasons. The concentration of heavy metals was determined using ICP OES. Next, the MTT assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] was employed to ascertain the survival rate of A549 cells. The findings from this research demonstrated that average PM2.5 of the study period was (149.5 µg/m3). Also, the average concentration of PM2.5 in the urban area in winter and summer was (153.3- and 106.9 µg/m3) and in the industrial area this parameter was (191.6 and 158.3 µg/m3). The average concentration of metals (ng/m3) of urban areas against industrial, Al (493 vs. 485), Fe (536 vs. 612), Cu (198 vs. 212), Ni (128 vs. 129), Cr (48.5 vs. 54), Cd (118 vs. 124), Mn (120 vs. 119), As (51 vs. 67), Hg (37 vs. 50), Zn (302 vs. 332) and Pb (266 vs. 351) were obtained. The results of the MTT assay showed that the highest percentage of cell survival according to the exposure concentration was 25 > 50 > 100 > 200. Also, the lowest percentage of survival (58.8%) was observed in the winter season and in industrial areas with a concentration of 200 µg/ml. The carcinogenic risk assessment of heavy metals indicated that except for Cr, whose carcinogenicity was 1.32E-03, other metals were in the safe range (10-4-10-6) for human health. The high concentration of PM2.5 and heavy metals can increase respiratory and cardiovascular diseases and reduce the public health level of Ahvaz citizens.


Subject(s)
Air Pollutants , Metals, Heavy , Humans , Particulate Matter/toxicity , Particulate Matter/analysis , Environmental Monitoring/methods , Metals, Heavy/toxicity , Metals, Heavy/analysis , Seasons , Middle East , Risk Assessment , Air Pollutants/toxicity , Air Pollutants/analysis , China
12.
Sci Rep ; 13(1): 16185, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37758793

ABSTRACT

Antibiotics are resistant compounds with low biological degradation that generally cannot be removed by conventional wastewater treatment processes. The use of yolk-shell nanostructures in spinning disc photocatalytic reactor (SDPR) enhances the removal efficiency due to their high surface-to-volume ratio and increased interaction between catalyst particles and reactants. The purpose of this study is to investigate the SDPR equipped to Fe3O4@void@CuO/ZnO yolk-shell thin film nanostructure (FCZ YS) in the presence of visible light illumination in the photocatalytic degradation of amoxicillin (AMX) from aqueous solutions. Stober, co-precipitation, and self-transformation methods were used for the synthesis of FCZ YS thin film nanostructure and the physical and chemical characteristics of the catalyst were analyzed by XRD, VSM,, EDX, FESEM, TEM, AFM, BET, contact angle (CA), and DRS. Then, the effect of different parameters including pH (3-11), initial concentration of AMX (10-50 mg/L), flow rate (10-25 mL/s) and rotational speed (100-400 rpm) at different times in the photocatalytic degradation of AMX were studied. The obtained results indicated that the highest degradation efficiency of 97.6% and constant reaction rate of AMX were obtained under LED visible light illumination and optimal conditions of pH = 5, initial AMX concentration of 30 mg/L, solution flow rate of 15 mL/s, rotational speed of 300 rpm and illumination time of 80 min. The durability and reusability of the nanostructure were tested, that after 5 runs had a suitable degradation rate. Considering the appropriate efficiency of amoxicillin degradation by FCZ YS nanostructure, the use of Fe3O4@void@CuO/ZnO thin film in SDPR is suggested in water and wastewater treatment processes.

13.
Int J Environ Health Res ; : 1-15, 2023 Sep 06.
Article in English | MEDLINE | ID: mdl-37674318

ABSTRACT

Epidemiological studies on air pollution, diabetes, and hypertension conflict. This study examined air pollution, diabetes, and hypertension in adults in 11 metropolitan areas of Iran (2012-2016). Local environment departments and the Tehran Air Quality Control Company provided air quality data. The VIZIT website and Stepwise Approach to Chronic Disease Risk Factor Surveillance study delivered chronic disease data. Multiple logistic regression and generalized estimating equations evaluated air pollution-related diabetes and hypertension. In Isfahan, Ahvaz, and Tehran, PM2.5 was linked to diabetes. In all cities except Urmia, Yasuj, and Yazd, PM2.5 was statistically related to hypertension. O3 was connected to hypertension in Ahvaz, Tehran, and Shiraz, whereas NO2 was not. BMI and gender predict hypertension and diabetes. Diabetes, SBP, and total cholesterol were correlated. Iran's largest cities' poor air quality may promote diabetes and hypertension. PM2.5 impacts many cities' outcomes. Therefore, politicians and specialists have to control air pollution.

14.
Sci Rep ; 13(1): 11113, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37429926

ABSTRACT

In this research, we synthesized BiOI/NH2-MIL125(Ti) via solvo-thermal method to investigation of oxytetracycline (OTC) degradation in photocatalytic-ozonation process. The results of the XRD, FESEM, EDAX, FTIR, UV-Vis, TEM, XPS, and BET analyzes indicated that the catalyst BiOI/MOF was synthesized with excellent quality. Design of experiment (DOE), ANOVA statistical analysis, interaction of parameters and predicated optimum condition was done based on CCD. The effect of catalyst dose (0.25-0.5 mg/l), pH (4-8), reaction time (30-60 min) and O3 concentration (20-40 mN) at 10 mg/l of OTC on PCO/O3 process was optimized. Based on P-value and F-value coefficients (0.0001, 450.3 respectively) the model of OTC (F-value = 2451.04) and (P-value = 0.0001) coefficients, the model of COD removal was quadratic model. Under optimum condition pH 8.0, CD = 0.34 mg/l, RT = 56 min and O3 concentration = 28.7 mN, 96.2 and 77.2% of OTC and COD removed, respectively. The reduction of TOC was 64.2% in optimal conditions, which is less than the reduction of COD and OTC. The kinetics of reaction followed pseudo-first-order kinetic (R2 = 0.99). Synergistic effect coefficient was 1.31 that indicated ozonation, presence of catalyst and photolysis had a synergistic effect on OTC removal. The stability and reusability of the catalyst in six consecutive operating steps was acceptable and 7% efficiency decreased only. Cations (Mg2+, and Ca2+), SO42- had no influence on performing the process, but other anions, organic scavengers, and nitrogen gas, had an inhibitory effect. Finally, the OTC degradation probably pathway includes direct and indirect oxidation that decarboxylation, hydroxylation, demethylation and were the main mechanism in OTC degradation.

15.
Ecotoxicol Environ Saf ; 263: 115229, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37441953

ABSTRACT

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.


Subject(s)
Chlorpyrifos , Cucumis melo , Pesticide Residues , Pesticides , Adult , Child , Humans , Pesticide Residues/analysis , Chlorpyrifos/analysis , Diazinon , Malathion , Soil , Iran , Monte Carlo Method , Pesticides/analysis , Risk Assessment
16.
Heliyon ; 9(6): e17357, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37383194

ABSTRACT

Shahryar city regions with various land uses had their outdoor air concentrations of PM2.5-bound PAHs determined. Totally, 32 samples were taken - eight samples from the industrial region air (IS), eight samples from the high-traffic urban regions air (HTS), eight samples from the air of commercial regions (CS), and eight samples from residential areas (RS), which were analyzed by GC-MS. According to the study's findings, in the outdoor air of IS, HTS, CS, and RS, there were mean Æ©PAHs concentrations of 23.25 ± 20.22, 38.88 ± 26.53, 6.97 ± 4.26, and 4.48 ± 3.13 ng/m3, respectively. As comparison to CS and RS, mean concentration of Æ©PAHs in samples from HTS and IS was substantially greater (p < 0.05). Using the Unmix.6 receptor model, sources of PAHs in the air of Shahryar were allocated. The model's results show that 42% of PAHs come from diesel vehicles and industrial activities, 36% from traffic and other transportation sources, and 22% from heating sources and coal burning. The carcinogenicity suffering resulting from exposure to PAHs was as follows: This value for children of the ingestion, inhalation pathways and dermal contact is (1.90 × 10-6-1.38 × 10-4), (5.5 × 10-11-2.67 × 10-9) and (2.36 × 10-6-1.72 × 10-4), respectively. Also, for adults were (1.47 × 10-6 - 1.07 × 10-4), (1.14 × 10-10 - 5.27 × 10-9) and (3.68 × 10-6- 2.87 × 10-4), respectively. In general, the analyzed region's carcinogenicity risk estimates fell within the range of acceptable limit.

17.
Heliyon ; 9(4): e15574, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37128311

ABSTRACT

Over the recent years, due to the increase in the population covered by local wastewater treatment plants (WWTP), upgrading the existing treatment plants needs special attention more than ever. One of the suggested solutions removal the existing sludge treatment units in local WWTP and transfer the sludge to a centralized WWTP. The present study was developed to investigate the hydraulic feasibility of sludge transfer from Shahrak-e-GharbWWTP as a local treatment plant to South Tehran sewage treatment plant in Tehran. To this end, at first, a map containing descriptive information and hydraulic characteristics related to the sewage transmission network between local and centralized WWTP was collected from the sewage company. This information was used to calculate the maximum capacity, current flow and draw the hydraulic profile of the sewage transmission line. Then, the transmission line profile was drawn using Manning's hydraulic model and SewerCAD v10.01 software. According to the obtained results, areas 1 and 3 with sewage line diameters of 1000 and 1400 mm did not have any special problem in terms of entering the sludge. Hydraulic analyzes showed that some lines in areas 2, 4, 5, and 6 suffered setbacks and crises after the increase of sludge, which require auxiliary lines. The results indicated that more than 85% of the sewage network lines have the ability to transfer the excess sludge of the local treatment plant, however, in 36 lines, mostly located in zones 2 and 6, with a diameter of 1200 and 2000 mm, there is a crisis of sewage filling and backflow. Therefore, in order to reduce hydraulic stresses in these lines, it was suggested to build an auxiliary line (bypass ring at the beginning and end of these lines).

18.
Sci Rep ; 13(1): 4000, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36899090

ABSTRACT

In this study, toluene and ethylbenzene were degraded in the photocatalytic-proxone process using BiOI@NH2-MIL125(Ti)/Zeolite nanocomposite. The simultaneous presence of ozone and hydrogen peroxide is known as the proxone process. Nanocomposite Synthesis was carried out using the solvothermal method. Inlet airflow, ozone concentrations, H2O2 concentrations, relative humidity, and initial pollutants concentrations were studied. The nanocomposite was successfully synthesized based on FT-IR, BET, XRD, FESEM, EDS element mapping, UV-Vis spectra and TEM analysis. A flow rate of 0.1 L min-1, 0.3 mg min-1 of ozone, 150 ppm of hydrogen peroxide, 45% relative humidity, and 50 ppmv of pollutants were found to be optimal operating conditions. Both pollutants were degraded in excess of 95% under these conditions. For toluene and ethylbenzene, the synergistic of mechanisms effect coefficients were 1.56 and 1.76, respectively. It remained above 95% efficiency 7 times in the hybrid process and had good stability. Photocatalytic-proxone processes were evaluated for stability over 180 min. The remaining ozone levels in the process was insignificant (0.01 mg min-1). The CO2 and CO production in the photocatalytic-proxone process were 58.4, 5.7 ppm for toluene and 53.7, and 5.5 ppm for ethylbenzene respectively. Oxygen gas promoted and nitrogen gas had an inhibitory effect on the effective removal of pollutants. During the pollutants oxidation, various organic intermediates were identified.

19.
J Environ Health Sci Eng ; 20(2): 937-952, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36406604

ABSTRACT

One of the popular process in volatile organic compounds removal in gas phase is advanced oxidation process. We in this research, synthesized BiOI@NH2-MIL125(Ti)/Zeolite nanocomposite as a novel nanocomposite to degradation of benzene in hybrid advanced oxidation process. The nanocomposite synthesized via solvothermal method. The effect of airflow, ozone gas concentration, hydrogen peroxide concentration, relative humidity and initial benzene concentration are the main parameters in the UV/O3/H2O2/ nanocomposite hybrid process that were studied. The characterization by XRD, FT-IR, FESEM, EDS element mapping, TEM, BET, and UV-vis spectra indicated that nanocomposite were well synthesized. Optimal operating conditions of the process were determined at air flow of 0.1 l/min, ozone concentration of 0.3 mg/min, hydrogen peroxide concentration of 150 ppm, relative humidity of 45 ± 3% and benzene concentration of 50 ppmv. Under these conditions, more than 99% of benzene was degraded. The synergistic effect coefficient of the mechanisms is 1.53. The nanocomposite had good stability in the hybrid process and remained above 99% efficiency up to 5 times. The ozone concentration residual the system was reported to be negligible (0.013 mg/min). The CO and CO2 emissions in the hybrid process was higher than other processes, which indicates better mineralization in the hybrid process. Formaldehyde, octane, noonan, phenol, decanoic acid were reported as the main by-products. The results indicated that UV/O3/H2O2/ nanocomposite hybrid process has fantastic efficiency in the degradation of benzene as one of the indicators of VOCs.

20.
Environ Monit Assess ; 194(11): 812, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36131102

ABSTRACT

Polluted air affects human life and it is crucial to assess air pollutants to inform policy and protect human lives. In this study, we sought to assess the respiratory outcomes associated with PM10, O3, SO2, and NO2 in the Iranian population. The required data, which included concentrations of air pollutants, meteorology, and population size, were obtained from the department of environment and meteorological organizations. The validity of the data was evaluated, and appropriate calculations were conducted on the data to extract the required values and parameters for modeling (using the AirQ2.2.3). This study was conducted in two megacities of Iran (Tabriz and Urmia) with over 2 million population. The annual averages of SO2, NO2, and PM10 concentrations were 9, 73, and 43 µg/m3 in Tabriz and 76, 29, and 76 µg/m3 in Urmia, respectively. Excess deaths from respiratory diseases associated with PM10 and SO2 were estimated to be 33.1 and 1.2 cases in Tabriz and 31.6 and 24.7 cases in Urmia, respectively. The proportions of hospitalizations for chronic obstructive pulmonary disease (COPD) attributable to SO2 and NO2 in Tabriz were 0.07% and 1.61%, respectively, whereas they were 2.84% and 0.48% in Urmia. O3 had an annual average of 56 µg/m3 in Tabriz and with 44.5 excess respiratory deaths and 42.5 excess hospital admissions for COPD, it had the greatest health impacts among the pollutants studied. Findings from this study add to the growing literature, especially from developing countries, that provides insights to help authorities and decision-makers develop and implement effective interventions to curb air pollution and save lives.


Subject(s)
Air Pollutants , Air Pollution , Environmental Pollutants , Pulmonary Disease, Chronic Obstructive , Air Pollutants/analysis , Air Pollution/analysis , Environmental Monitoring , Humans , Iran/epidemiology , Nitrogen Dioxide/analysis , Outcome Assessment, Health Care , Particulate Matter/analysis , Pulmonary Disease, Chronic Obstructive/epidemiology
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