Influence of Air Pollution on Chemical Quality of Wet Atmospheric Deposition: a Case Study in Urmia, Iran

Increased combustion of fossil fuel owing to the energy requirement is a main cause of air pollution throughout the world. Atmospheric precipitation is considered as a major water resource for indoor, municipal, industrial and agricultural uses. This study was aimed to evaluate the effect of air pollution on chemical quality of rain and snow in Urmia, a city in northwest of Iran. Sampling was performed during the wet seasons from October to March at six sampling stations in different locations of the city. Acidity, alkalinity, NO3- , SO42-, Cl- and pH contents of the collected samples were analyzed. All samples showed a pH value of more than 6.8, and lower acidity than alkalinity, therefore, the precipitations were not acidic. Maximum concentrations of SO42- and NO3- in the samples were 5 and 8.8mg/L, respectively. Chloride was varied from 1 to 11.5 mg/L with the highest measures observing in autumn. According to the results, concentrations of the analyzed parameters in wet precipitations in Urmia were within the natural ranges except chloride ions, which was higher than its common level in the atmosphere. This phenomenon may be the result of desert dusts which transfers by wind from the west border to Iran.

The trend of changes in air quality index (AQI) in Mashhad using ‎GIS ‎

Introduction and Purpose: Mashhad, one of the most populous cities in Iran, is facing air pollution due to motor vehicle emissions and industries. Therefore, this study aimed to evaluate the variations in Air Quality Index (AQI) during the spring of 2012-2014 and its spatial zoning with Arc GIS. Methods: In this descriptive study, the AQI values were calculated by the associated pollutant concentrations including PM10, PM2.5, NO2, SO2, CO, and O3 obtained from four online stations in the city during the spring of 2012-2014. After classification of daily air quality into six categories (good, moderate, unhealthy for sensitive people, unhealthy, and very unhealthy), the spatial zoning was performed with Arc GIS. Results: Based on the results, the air quality of Mashhad was found to be good and moderate most days for which PM2.5 and NO2 emissions were recognized to be the main responsible pollutants. According to the zoning maps, AQI values were found to be in good conditions in Sadaf station located in the northwest of Mashhad, while the center and south of Mashhad were more polluted during 2012-2014. AQI values improved from April to June 2012-2013, while the values dropped in 2014.Conclusion: The air quality of Mashhad is unhealthy in the crowded southern and center regions of this city on some spring days. Consequently, some strategies, such as traffic management, employment of other types of fuel or quality improvement, management of home heating systems, and use of electric transportation should be considered as air pollution control options in the coming years

Evaluation of Seasonal and Spatial Variations of Air Quality Index and Ambient Air Pollutants in Isfahan Using Geographic Information System

Introduction: Due to more than 1.7 million population, many vehicles and large industries around Isfahan, it has become one of the most polluted cities in Iran. The aim of this study was a spatial analysis of the concentrations of air pollutants and the air quality index (AQI). Materials and Methods: In this descriptive and evaluative study, the air quality data of 7 monitoring stations in 2012 were taken from the Isfahan Department of Environment. The calculation of AQI was done as per the EPA guidelines. The zoning pollutant concentrations and AQI in the study area was determined with the use of the Arc map software, version 10.1. Results: The results showed that the highest concentrations of pollutants and the AQI were related to the Ahmadabad station. Moreover, the air quality in Isfahan in 2012 was 4.38% (4 days) in good conditions, 12.7% (47 days) in moderate conditions, 42.56% (156 days) in unhealthy conditions for sensitive groups, 39.49% (144 day) in unhealthy conditions, 2.8% (10 days) in a very unhealthy and 1.2% (4 days) in dangerous conditions, respectively. Conclusion: It was found that particulate matter was the main cause of Isfahan air pollution while Ahmadabad is the most polluted point in Isfahan. According to the calculations, during 314 days of the year 2012, the air quality of Isfahan was in unhealthy conditions and only 4 days was in good conditions. This is one of the biggest health challenges in this city

Mortality and morbidity due to exposure to Ambient NO2, SO2, and O3in Isfahan in 2013–2014

Background: The presence of air pollutants such as CO, NO2, SO2, O3, and PM in the ambient air mainly emitted from fossil fuels combustion has become a major health concern. The aims of this study were to estimate the attribution of NO2, SO2, and O3 in the premature deaths and prevalence of cardiovascular and respiratory diseases in Isfahan in 2013–2014. Methods: In this study, short-term health effects (total mortality, cardiovascular and respiratory mortality, chronic obstructive pulmonary disease, and acute myocardial infarction) of exposure NO2, SO2, and O3 on the population of Isfahan were assessed using AirQ 2.2.3 software suggested by the World Health Organization (WHO). Results: The result showed that from nonaccident total mortality in 2013–2014 in Isfahan, the attributable proportion related to NO2, SO2, and O3 were 1.03% (109 cases), 3.46% (365 cases), and 1.29% (136 cases), respectively. The percentage of days that people were exposed to the highest concentration of NO2 (40–49 μg/m3), SO2 (60–69 μg/m3), and O3 (40–49 μg/m3) was 34.46%, 16.85%, and 42.74% of a year, respectively. Total mortality attributed to NO2, SO2, and O3exposure was 0.36%, 0.79%, and 0.83%, respectively. Conclusions: The concentrations of NO2and SO2were upper than the WHO guidelines. The Air-Q software in spite of its limitations can provide useful information regarding the health outcome of the air pollutants. The results estimated in this study were considerable. This information can help the health authorities and policy makers to draw suitable strategies and fulfill effective emission control programs

Prediction of atmospheric PM2.5 level by machine learning techniques in Isfahan, Iran

Abstract With increasing levels of air pollution, air quality prediction has attracted more attention. Mathematical models are being developed by researchers to achieve precise predictions. Monitoring and prediction of atmospheric PM2.5 levels, as a predominant pollutant, is essential in emission mitigation programs. In this study, meteorological datasets from 9 years in Isfahan city, a large metropolis of Iran, were applied to predict the PM2.5 levels, using four machine learning algorithms including Artificial Neural |Networks (ANNs), K-Nearest-Neighbors (KNN), Support Vector |Machines (SVMs) and ensembles of classification trees Random Forest (RF). The data from 7 air quality monitoring stations located in Isfahan City were taken into consideration. The Confusion Matrix and Cross-Entropy Loss were used to analyze the performance of classification models. Several parameters, including sensitivity, specificity, accuracy, F1 score, precision, and the area under the curve (AUC), are computed to assess model performance. Finally, by introducing the predicted data for 2020 into ArcGIS software and using the IDW (Inverse Distance Weighting) method, interpolation was conducted for the area of Isfahan city and the pollution map was illustrated for each month of the year. The results showed that, based on the accuracy percentage, the ANN model has a better performance (90.1%) in predicting PM2.5 grades compared to the other models for the applied meteorological dataset, followed by RF (86.1%), SVM (84.6%) and KNN (82.2%) models, respectively. Therefore, ANN modelling provides a feasible procedure for the managerial planning of air pollution control

Assessment of Airborne Asbestos Fibers Concentration in Yazd City in Summer 2015

Introduction: Today, have been approved scientifically relationship between presence of asbestos fibers in the human respiratory area and malignant diseases such as lung advanced fibrosis (Asbestosis), gastrointestinal, lung and Laryngeal cancers. The aim of this study was the determination of asbestos fibers concentration in Yazd city’s air in the summer of 2015. Materials and Methods: This is a descriptive cross sectional study in which 13 high-traffic points of Yazd city were selected for asbestos sampling. Sampling was conducted in the summer in two stages using SKC pump. In total were collected 26 samples from the high traffic points of Yazd city. Also for the counting of asbestos fibers was used scanning electron microscopy (SEM). Results: In the current research, the highest and the lowest concentration of asbestos fibers were related to Shohadayemehrab square (0.02131fiber/ml) and Azadshahr (0.00112 fiber/ml) respectively. Qualitative analysis of asbestos fibers by SEM showed that 75% of the samples were asbestos fibers and the other was non-asbestos fibers. Conclusion: The present study showed that the average of asbestos fibers concentration in total sampling stations (0.00848 fiber/ml) was higher than WHO guidelines (2.2 × 10-3 fiber/ml). The main reason for the presence of these fibers in the air of Yazd city can be attributed to brake pad, clutch and automobile gasket adhesive

The performance of TiO2/NaY-zeolite nanocomposite in photocatalytic degradation of Microcystin-LR from aqueous solutions: Optimization by response surface methodology (RSM)

Background: Microcystin (MC) is a hepatotoxic and carcinogenic toxin that is generated by cyanotoxins which can have adverse effects on the human health. Therefore, it is very important to remove it from the environment. This study was performed to investigate the efficiency of titanium dioxide (TiO2)/ NaY-zeolite (T/N-Z) nanocomposite for removal of MC-LR under ultraviolet light. Methods: In the present study, T/N-Z nanocomposite was synthesized using the hydrothermal method. Specification of the photocatalysts was determined by the field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) spectra. The response surface methodology (RSM) was used to survey the effects of operating variables such as pH, contact time, and catalyst dose on the removal of MC-LR. The MC-LR concentration was measured by high-performance liquid chromatography (HPLC). Results: It was revealed that the increase of contact time and catalyst dose had a positive effect on enhancing the removal efficiency of MC-LR, but pH had a negative effect. Finally, the maximum MCLR removal efficiency was 97.63%, which occurred at pH = 5, contact time = 120 min, and catalyst dose = 1.2 g/L. Conclusion: In general, T/N-Z composite in aqueous solutions under the UV light can easily decompose MC-LR and it can also be proposed as an efficient composite for removal of MC-LR from contaminated water. Keywords: Microcystin, Titanium dioxide, Zeolite, Photocatalytic degradation, High-performance liquid chromatograph

Determination of Health Effects Related to Particular Matter (PM2.5) in Ambient Air of Urmia City

International agency for research on cancer (IARC) has defined outdoor air pollution as a mixture and particulate matter specifically as carcinogenic to humans (IARC Group 1). Outdoor air pollution is a combination of different pollutants result from natural and man-made sources. This study aimed to evaluate exposure to PM2.5 and its effects on human health in north-west of Iran during 2015 to 2016 using AirQ model. The data were taken from online monitoring stations in Urmia city and total mortality estimated using AirQ model. The annual mean of PM2.5 concentrations was 23 μg/m3, which was too higher than 10 μg/m3 recommended by world health organization (WHO) guideline. The total cases for mortality in central relative risk 1.015 were found 143 cases. The main sources of PM were the combustion of fossil fuel. The salty dust storms caused by climate change and drying Urmia Lake. Therefore, increasing green space and extensive activities such as desertification are need to control this phenomenon that is extremely challenging

Influence of Air Pollution on Chemical Quality of Wet Atmospheric Deposition: a Case Study in Urmia, Iran

Increased combustion of fossil fuel owing to the energy requirement is a main cause of air pollution throughout the world. Atmospheric precipitation is considered as a major water resource for indoor, municipal, industrial and agricultural uses. This study was aimed to evaluate the effect of air pollution on chemical quality of rain and snow in Urmia, a city in northwest of Iran. Sampling was performed during the wet seasons from October to March at six sampling stations in different locations of the city. Acidity, alkalinity, NO3- , SO42-, Cl- and pH contents of the collected samples were analyzed. All samples showed a pH value of more than 6.8, and lower acidity than alkalinity, therefore, the precipitations were not acidic. Maximum concentrations of SO42- and NO3- in the samples were 5 and 8.8mg/L, respectively. Chloride was varied from 1 to 11.5 mg/L with the highest measures observing in autumn. According to the results, concentrations of the analyzed parameters in wet precipitations in Urmia were within the natural ranges except chloride ions, which was higher than its common level in the atmosphere. This phenomenon may be the result of desert dusts which transfers by wind from the west border to Iran.

Health risk assessment due to the presence of heavy metals in drinking water resources of Maragheh city

Background and Objective: Heavy metals in water can pose risks to human health. Therefore, it is necessary to monitor and measure metals to ensure the health of consumers. Materials and Methods: This study aimed to measure heavy metals such as arsenic, lead, cadmium, chromium, zinc, and mercury in water resources and urban water distribution networks in spring and summer of 2021 in Maragheh city. Accordingly, 25 samples were taken to investigate the presence of heavy metals. The presence of these metals in water sources was investigated using qualitative maps and finally, by evaluating the health risk caused by the presence of these metals, their effect on the health of consumers has been studied. Results: Examining the concentration of metals in water resources upstream of the dam shows a relatively high concentration of metals, especially arsenic (13.2 µg/L). Despite this, the amount of arsenic after the water treatment plant and in the distribution network is reduced to an insignificant level. On the other hand, the results show that the amount of zinc metal in the network is higher than in the reservoir of the dam, and its concentration in the dam is equal to zero and in the network, it reaches the highest value of 578 µg/L. Finally, the health risk assessment shows that the calculated THI values for all samples vary between 0.01 and 0.99. Conclusion: Based on the calculated health risk, there is no threat to the health of consumers regarding heavy metals in Maragheh drinking water. Also, these results double the necessity of additional studies regarding the leakage of zinc metal from the pipes and accessories of the city's drinking water distribution network in the future