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.
Landfilling is known to be the most widely used method in municipal solid waste management in many countries. Landfill leachate containing different recalcitrant compounds are recognized to ...contaminate the soil and water and accordingly threat both the human health and environment. A variety of chemical and biological methods have recently been employed for landfill leachate treatment, one of which is the ultrasonic process. In this review, the efficiency of the ultrasound-assisted method for leachate treatment, factors influencing the treatment process are studied by defining a search protocol. The results showed that ultrasound can reduce pollutants by creating cavitation, microstreaming, and microturbulence. Increasing turbidity in initial of irradiation time and increasing the cost of treatment are the disadvantages of using ultrasonic in leachate treatment. Moreover, ultrasound-assisted method leads to improve the leachate quality, especially the COD/BOD. Therefore, ultrasound can be considered a good pretreatment for biological processes. Although, the application of this process in combination with other treatment processes such as biological processes and advanced oxidation increases the efficiency of leachate treatment, its efficiency depends on several factors such as exploitation features and leachate quality.
Background: One of the concerns faced by many countries, especially developing countries, is the presence of heavy metals in water, air and food, which directly and indirectly cause adverse effects ...on human health through inhalation and ingestion. Rudbar city is suitable for growing olives due to its climatic conditions, and most of the people living in the area use this product in their meals. The purpose of this study was to determine the amount of heavy metals manganese, iron, copper, zinc (Zn), lead and cadmium in the olives of this area. Methods: For this purpose, 13 olive samples were selected and their heavy metal concentration was measured by ICP-OES device. Results: The results indicated that the concentrations of cadmium, lead, manganese, iron, Zn and copper in the samples of Guilan olives were 0.056±0.019, 0.564±0.170, 2.017±0.211, 7.577±1.312, 1.846±0.387 and 4.147±0.901, respectively. Also, in the imported samples it was 0.065±0.014, 0.494±0.153, 1.295±0.353, 3.465±1.066, 1.357. 0.412 and 4.103±1.335, respectively. Conclusion: Except for one, the amount of lead in all Iranian samples was less than the allowable level. It was also observed that except for lead, the concentration of all metals in foreign samples was lower than Iranian samples. Since olives are one of the most popular food items in the area and considered by travelers, continuous monitoring of the heavy metals in this food is essential.
The likelihood of surface water and groundwater contamination is higher in regions close to landfills due to the possibility of leachate percolation, which is a potential source of pollution. ...Therefore, proposing a reliable framework for monitoring leachate and groundwater parameters is an essential task for the managers and authorities of water quality control. For this purpose, an efficient hybrid artificial intelligence model based on grey wolf metaheuristic optimization algorithm and extreme learning machine (ELM-GWO) is used for predicting landfill leachate quality (COD and BOD5) and groundwater quality (turbidity and EC) at the Saravan landfill, Rasht, Iran. In this study, leachate and groundwater samples were collected from the Saravan landfill and monitoring wells. Moreover, the concentration of different physico-chemical parameters and heavy metal concentration in leachate (Cd, Cr, Cu, Fe, Ni, Pb, Mn, Zn, turbidity, Ca, Na, NO3, Cl, K, COD, and BOD5) and in groundwater (Cd, Cr, Cu, Fe, Ni, Pb, Mn, Zn, turbidity, EC, TDS, pH, Cl, Na, NO3, and K). The results obtained from ELM-GWO were compared with four different artificial intelligence models: multivariate adaptive regression splines (MARS), extreme learning machine (ELM), multilayer perceptron artificial neural network (MLPANN), and multilayer perceptron artificial neural network integrated with grey wolf metaheuristic optimization algorithm (MLPANN-GWO). The results of this study confirm that ELM-GWO considerably enhanced the predictive performance of the MLPANN-GWO, ELM, MLPANN, and MARS models in terms of the root-mean-square error, respectively, by 43.07%, 73.88%, 74.5%, and 88.55% for COD; 23.91%, 59.31%, 62.85%, and 77.71% for BOD5; 14.08%, 47.86%, 53.43%, and 57.04% for turbidity; and 38.57%, 59.64%, 67.94%, and 74.76% for EC. Therefore, ELM-GWO can be applied as a robust approach for investigating leachate and groundwater quality parameters in different landfill sites.
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.
•Mortality statistics, number of people in required age groups, were gathered respectively from different organs.•by using Excel, the average 24-hour and 1-hour concentration and maximum 8-hour concentration for PM10, NO2, O3 pollutants were gathered.•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.
Background: In general, although the placenta is a good barrier to prevent infections, several cases of coronavirus disease 19 (COVID-19) transmission have been reported during pregnancy. Moreover, ...considering the potential for vertical maternal-fetal transmission, there is a concern that the fetus is at risk for congenital COVID-19. The aim of the present review and systematic study was to investigate the possibility of the vertical transmission of COVID-19 during pregnancy, labor, and postpartum using available data. Methods: Studies conducted by February 12, 2021 were included in this systematic review study. Articles were searched in Medline, Magiran, SID, Civilica, Irandoc, ScienceDirect, PubMed, EMBASE, Web of Science, Scopus, and Google Scholar using English keywords such as "Coronavirus", "COVID-19, "SARS-CoV-2", "Vertical intrauterine transmission", "Vertical transmission", "Vertical fetal infection", "Maternal infection", and "Fetal infection". The inclusion criterion included all observational studies related to vertical maternal-fetal transmission. Overall, 31 articles were completely analyzed after reviewing and deleting non-eligible and duplicate articles. Results: The results of reviewing 24 studies showed that collected samples were all negative but positive blood samples, immunoglobulin M (IgM) and IgG antibodies, and expression of placental factors were reported in seven studies. Conclusion: Although contradictory results were found in this study, the results of the samples revealed the lowest probability of vertical transmission. There was also no evidence confirming the effectiveness of cesarean section in reducing the rate of transmission. In general, adherence to hygienic protocols can have a significant impact on reducing neonatal incidence.
The coastal pollution has been evaluated using indexes like Clean Coast Index (CCI) in many countries. In this study, several coasts and urban areas in northern of Iran along the Caspian Sea, were ...assessed in terms of number and composition of litters. Furthermore, Clean Environment Index (CEI) was used for the first time to interpret the results. The results indicated that 60% of the coasts and 50% of the urban areas were in a dirty status and only 22% of the total surveyed areas were found to be in a clean status. The highest number of litters observed in the study areas was cigarette butt. Due to the impact of risk factor of different types of littered waste, it was obviously clear that CEI offers a more realistic and rigorous interpretation than CCI. Therefore, this new index can be considered to evaluate litters pollution in various areas.
•Litters are most common pollution in beaches and urban environments.•Plastic group as most abundant litters consist 39.54% in total studied areas.•CCI showed that 40% of coasts are in clean, 40% in moderate, 20% in dirty status.•CEI showed that 60% of coasts and 50% of urban areas are in dirty status.•The number and composition of litters on the coasts varied with different land-uses.
The COVID-19 pandemic has affected everyone’s lifestyle and this has resulted in a change in the quantity and composition of municipal solid wastes. Moreover, the post-pandemic waste management is ...very important as a bad management may lead to the more spread of the disease. The objective of this study was to evaluate the application of guidelines presented for the era of the COVID-19 pandemic in proper solid waste management. To this end, the data were collected by using interviews and field researches and then the obtained data were compared with the international guidelines presented by international organizations. By investigating the municipal waste management during this pandemic and its changes compared to pre-COVID-19, coordination of the plans with the guidelines was investigated. The activities of storage, collection, transportation, recycling, final landfill, as well as the observation of the health instructions by staff and informal sections were assessed in the current research. Although the results showed that the situation was satisfactory in the sections like health and safety of waste management operators due to the existence of protocols and general educations, the waste management plans have not been changed much from before the epidemic of the Coronavirus. The absence of a national policy and plan for waste management in the era of a pandemic and ignoring the guidelines developed by other countries and organizations were observable. Therefore, the codification of new policies for municipal waste management during an epidemic is necessary.
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•Acetaldehyde is a volatile organic compound derived from natural and human resources and industry.•SEM, XRD, BET, EDX, and FTIR analyzes were used to determine the catalyst ...properties.•The removal efficiency increased with increasing temperature, time, catalyst dose, and decreasing pollutant concentration.•The highest degradation efficiency was 67% at 50 ppm, 30% relative humidity, and 35 °C after 120 minutes of irradiation.•The results showed that MIL100(Fe) is a successful catalyst for photocatalytic degradation of gaseous acetaldehyde.
Increasing environmental pollution of human origin, especially air pollution, is one of the concerns of politicians in the past, present, and future, which has attracted attention to the processes developed to eliminate these pollutants and resolve the crisis. Acetaldehyde is a volatile organic compound derived from natural and human resources and industry. The present study aimed to evaluate the photocatalytic oxidation efficiency of MIL100(Fe) coated on glass under visible light irradiation for acetaldehyde removal. SEM, XRD, BET, EDX, and FTIR analyzes were used to determine the catalyst properties. The effect of parameters such as initial pollutant concentration, catalyst dose, temperature, time, and relative humidity was investigated. It was observed that the removal efficiency increased with increasing temperature, time, catalyst dose, and decreasing the input pollutant concentration. The highest degradation efficiency was 67% at 50 ppm, 30% relative humidity, and 35 °C after 120 min of irradiation. The results showed that MIL100(Fe) nanoparticles could be used as a successful catalyst in building materials, including glass, to reduce the amount of acetaldehyde and outher pollutant in indoor environments of homes and industries. This study highlights the need to remove acetaldehyde contaminants in gaseous media.
The penetration of landfill leachate into the subsoil contaminates soil and groundwater and has a negative effect on health. Therefore, the present study was conducted to investigate the quality and ...health risk of groundwater around Saravan landfill in Guilan province. To determine the effects of landfill on groundwater, leachate and water sampling of 5 wells around Landfill were performed according to standard procedures. The sampling was repeated 2 times and the samples were run through 0.45 Wattman filters to measure heavy metals. Then physico-chemical parameters were analysed and the results were compared with WHO standard and Environmental Protection Organization of Iran. Finally, the water quality index and potential health risks in children and adults were calculated. The results showed that the high pH of the leachate indicates the long life of the landfill. The concentrations of chromium, lead and manganese were higher than the allowed amount. The results of non-carcinogenic cumulative risk assessment in children and adults were 4.77 and 2.48 and the result of carcinogenic cumulative risk assessment in children and adults were 11 × 10
−3
and 23 × 10
−3
, respectively Also, the health risk index of heavy metals for lead and manganese in gastrointestinal and cutaneous exposure in children was more than 1, respectively. Water quality index of 68.935 was obtained which was lower than recommended. According to the findings, the waste burial in Saravan landfill has led to a decrease in the quality of adjacent groundwater. The results of heavy metal concentrations and their health risk assessment showed the potential for pathogenic risk to the health of groundwater consumers in the study area. Therefore, due to the proximity of water wells to Saravan landfills and possible changes in the concentration of heavy metals, continuous monitoring is necessary.
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