The monthly total amount of dust fall, as well as its chemical and physical characteristics, was systematically investigated in Shuwaikh city, Kuwait. dust samples were collected on a monthly basis for the entire year of 2009 and analyzed in the laboratory for water-soluble and water-insoluble matter. Water-insoluble matter represented the major portion of the total annual dust. ANOVAs showed significant temporal variation in the concentration of dust fall over the months (p < 0.05). Higher dust deposits were encountered between June and August and ranged from 76.4 to 97.6 ± 2.5 (SD) ton km-2 month-1, where dusty winds and low humidity are a common attribute in such arid areas. The main three soluble matter species measured are nitrate, sulfate, and chloride, and sulfate was found to be the most abundant inorganic species, ranging from 0.72 ± 0.13 to 4.1 ± 0.3 ton km-2 month-1. Major insoluble matter species measured are ash, silica, combustible, and tarry. Ash, silica, and combustible account for 63, 19, and 17.8 % of total insoluble dust, and 58.4, 17.7, and 16.6 % of total dust, respectively. Particle size distribution was also investigated, and results showed that dust particles >7 mm were the highest concentration of falling dust. Metrological conditions were found to play a vital role in temporal variations in falling dust.

The purpose of this study was to assess some heavy metal (HM) concentrations in the soil and atmospheric falling dust along the Yazd highway, Yazd Province, Iran. The total concentrations of cadmium (Cd), cobalt (Co), copper (Cu), nickle (Ni), lead (Pb), zinc (Zn), iron (Fe) and manganese (Mn) in the dust and soil samples were measured using atomic absorption spectrophotometry after digestion with acid. The relationship between HMs in the falling dust was determined using correlation coefficients, principal component analysis and cluster analysis. The mean concentrations of HMs in falling dust were higher than those of the nearby soils, except for Fe, Pb and Zn. The highest correlation between HMs in the falling dust and soil was associated with Cd and Fe as well as Cd and Ni with the correlation coefficients of 0. 81 and 0. 97, respectively. Based on the principle component analysis, cluster analysis and correlation coefficients, two resources were identified for HM concentrations in the falling dust. The measurement of enrichment factor exhibited that the region dust infiltration of metals on Mn (13. 46), Zn (8. 16) and Cu (5. 21) are grouped in the severe enrichment class. Increasing industrialization and human activities lead to enter intensified levels of HMs into atmosphere. So, implementation of environmental standards and improvement of public transportation are necessary to reduce the level of pollutants entering the atmosphere.

Introduction dusts are referred to as aerosol particles that are made up of different sources of land and humanization, and after which time, again, they fall on the surface due to their size and density (Salman Zadeh et al., 2012). This phenomenon can damage infrastructures, telecommunications and agricultural products and affect transport through reduced visibility and cause a lot of economic damage. (Song et al 2007., Cao et al 2016). The purpose of this study is measuring and spatial analysis of the city of Tehran in a one-year statistical period. Materials and methods In this research, we used the laboratory method to measure falling dust, collecting dust using Marble dust Collector. For this purpose, the falling dust was collected using a Marble dust Collector in 28 stations in Tehran during the statistical period. In order to analyze the spatial distribution of dust, dust was collected from 28 dust collecting stations, and Tehran PM10 data taken from the air quality control company, the number of construction urban under construction in Tehran were obtained from Tehran Municipality Organization, mean maximum wind speed parameters, average relative humidity, days of rainfall above 5 mm, the average temperature of Tehran taken from the country's meteorological organization in the one-year statistical period (1/10/96-30/9/97) to enter the Arc Map10. 5 environment and preparing the desired layers Were prepared. Statistical analysis of the data showed that dust collected, pm10 and the number of running construction projects have regional (trend) behavior. Therefore, Universal trend is better suited. Due to the high preconditions for stagnation use of Universal trend In the area with fewer meteorological stations (Chitgar, Geophysics, Mehrabad and Shemiran) Universal trend is not applicable, Therefore, the IDW method was selected for climatic parameters. Also, the vegetation cover and factories file Shapes were taken and by analyzing Euclidean distance of each of these complications in GIS for Tehran, there impact on the dust in each area were considered. Then all the layers were weighed to determine the weights using the Reclassify tool. Then, using Expert Choice software, we compared all the layers two by two till estimate the value of each layer relative to the other layer. We multiplied the values obtained at each level. We transferred all layers to the Fuzzy Overlay tool. And draw up the final map of the spatial analysis of falling dust in Tehran city using the Gama 0. 9 function. Also, daily speed and wind direction data were received from the Meteorological Organization of the country during the one-year statistical period, (30/9/97-1/10/96). And with the help of the WRPLOT software for statistical analysis and the location of the wind, the windrose was drawn. Results and discussion The results of computations performed on the data obtained from the collecting of falling dust in Tehran showed that the weight of falling dust in the winter of 1396 is 18943. 5 tons, in the spring of 1397 it is equivalent to 27119. 5 tons, in the summer of 1397 it is equivalent to 17111. 2 tons and in the fall of 1397 it is equivalent to 23002. 3 tons. Also, the results showed that the highest falling dust was collected in spring, autumn, winter and summer, respectively. The spatial analysis map of Tehran's falling dust is a combination of 9 layers, based on the weight assigned to each layer. The results showed that the highest amount of dust in the winter of 1396 was found in west of Tehran. We had the lowest amount of falling dust in the north and northeast (regions 1 and 4). In the spring, summer and autumn of 1397, the halo of the most falling dust was displaced slightly eastward and settled in the southwest. The lowest amount of dusts in these seasons was located in the north and northeast. The halo with the lowest amount of dust falling has expanded further in the autumn than spring and summer. Conclusion The results of this study showed that the spatial distribution of falling dust varies in different seasons. Which shows that the source of falling dust in the city of Tehran is not uniform throughout the year. Field precise surveys have shown that the increase in falling dust in different parts of Tehran is directly related to urban construction. So that in the statistical year of the study, construction and subsequent falling dust has been less in eastern Tehran than its west and this increase is also associated with pm10. The largest amount of pm10 was reported from the west and southwest, which simultaneously collected the highest amount of falling dust. The highest density of factories and the lowest vegetation density are in these areas. The climatic factors also contributed to these conditions. So that, It was reported that the highest number of rainy days to exceed 5 mm was reported in north and north east of Tehran, where the lowest amount of dust was collected. And the highest average temperature in different seasons is reported from Southwest of Tehran, which has the highest amount of falling dust in spring, summer and autumn. But in winter climate conditions were slightly different from other seasons. So that, the highest relative humidity reported in other seasons from the West has been reported from north and northeast this season. The dust collected in winter is higher in the west than in the southwest. But the average maximum wind speed, which is in the west and south, is in the winter, spring and autumn to the west and southwest Which is from sand quarts of Quds, Shahriar, and Malard cities, especially the sandy-sand dune areas and abandoned agricultural land in Baharestan, Islam-Shahr and Robat-Karim, then dust from these areas enters Tehran west. In addition, the wind disperses the dusts generated by construction around the city. In the summer, in addition to the west and southwest, there is wind for north and south east. The northern wind comes from Shemiranat, bringing fresh air to the north and north-east of Tehran. The southeast wind passes from the Pakdasht sand and cement factories in Tehran and the abandoned agricultural land of Varamin and contains dust. The low wind speed in these areas gives more time to hangs off more particles. And of course, climatic conditions with the lowest relative humidity, the highest temperature, and a lack of rainfall above 5 mm also help to pollute the southern part of Tehran.

falling dust is containing particles with smaller than 100 microns in size, which is deposited on the surface. dust has an important role in transforming environmental pollutants. Strontium is one of these pollutants that are released into the atmosphere from natural and human sources and is falling to the ground by dust. Due to strontium has joint transportation routes with calcium can lead to hazards to human health. There are also radioactive isotopes of strontium; including strontium 90 is very harmful due to impaired blood flow. In this study the distribution and abundance of strontium, strontium isotopes found in the mist was falling. After selecting of the sampling stations with appropriate distribution in the city of Yazd is used sediment traps of marbles and dust samples were taken monthly for a year. In order to investigate the changes in the concentration of strontium in samples of dust from the X-ray fluorescence system and for the determination of strontium radioisotopes Geiger Muller instrument was used. Zoning map and local distribution of strontium in the city was prepared in Arc GIS software. The study results showed that the highest concentration of strontium is from the East to the city center and the lowest amount is related to the North West. Zoning results showed that the highest quantity of the strontium in the city center is from Kashani Street to the field Mahdieh. Radioactive isotopes of strontium showed that the samples are lacked radioactive isotopes. So there isn’ t any environmental risk from radio isotopes of strontium in falling dust.

Background: Heavy metals in falling dust are known pathogens for humans. The aim of this study was to identify potential sources, availability assessment, and degree of contamination of heavy metals in falling dust using SDM, CF, ER, and PERI indices. Methods: This descriptive-analytical cross-sectional study was carried out in autumn by installing 35 samplers of artificial grass to collect falling dust around Khak-e-chini, ceramic tile, sand and gravel, and Ardakan Glass industries. Heavy metals concentration in dust was measured using ICP-MS. All statistical analyses and calculations of indices were performed in SPSS 22 and Excel 2016. Results: The order of mean concentration of elements in the dust was manganese> vanadium> chromium> nickel> copper> arsenic> cobalt. Comparison of the concentration of dust elements with the background concentration and the results of principal component analysis and correlation tests showed that the concentration of all metals in the dust is probably influenced by two man-made sources in the area. The highest and lowest saturation degrees obtained were for manganese and cobalt, respectively. Based on the CF index, the manganese, cobalt, and vanadium were in low, medium, and high levels of pollution, respectively. Also, Arsenic, chromium, and nickel were classified in medium to high and copper in low to high classes. According to ERP and PERI indices, all heavy metals were classified in low pollution class. Conclusion: The investigated industries in this study have an important role in increasing the concentration and mobility of heavy metals in falling dust.

The study of heavy metals in dust fall is very important due to effects on human health. The purpose of the present study has been to determine the level of contamination and ecological risk of heavy metals such as Cd, Cr, Cu, Ni, Pb in the falling dust of Tehran city, and investigation spatial distribution of pollution on the studied stations. dust fallout samples were collected using Marble dust Collector (MDCO) from 28 different locations across the Tehran city, during the statistical period (from December 22nd, 2017 to June 21st, 2018). Contamination factor(CF), pollution Load index(PLI), The potential ecological risk coefficient(Er) and The potential toxicity response index(RI) were used to identify the level of contamination and ecological risk of heavy metals. The amount of (Cf), (PLI), (Er) and(RI) for the heavy metals in the dust fall in winter and spring 2018 followed the order of Pb>Cd>Cu>Cr>Ni. The concentrations of Lead, Copper and Cadmium in winter were significantly higher than those in spring. Stable air, temperature inversions and more heating devices are used in winter, causes that heavy metals are increased in this season. Areas located in the east of Tehran have the highest pollution and ecological risk in terms of cadmium, copper, nickel and lead. Most of the chromium contamination exists from the central areas to south of Tehran. Tehran's prevailing wind direction and Tehran's topographic pattern, mines, factories and industries located in the west and southwest of Tehran have main role in polluting Tehran's falling dust with heavy metals.

Background and Objective: Non-biodegradation in nature and creation of adverse health effects in humans is important features of heavy metals. The main objective of this study was to determine the level of contamination, carcinogenic and non-carcinogenic risks of falling dust containing heavy metals on residents around the industrial areas of Ardakan. Another objective was to identify potential sources of heavy metal release into the environment. Materials and Methods: In this cross-sectional analytical study, the falling dust was collected in summer around Tile and Ceramic, Khak-e-chini, sand and gravel and glass industries by installing 35 Inverted Frisbee traps with artificial grass cover. The concentration of Cd, Ba, Cu, Ni, Cr, Mn and V were measured by ICP-MS. Probable sources of the heavy metal of the dust were evaluated using Pearson correlation coefficient and cluster analysis. Ecological risk indices for determining the level of contamination and proposed relationships proposed by the US Environmental Protection Agency were used to assess the carcinogenic and non-carcinogenic risks. Results: The highest and lowest mean concentrations of heavy metals were measured for Cd and Ba, respectively. The results of Pearson correlation analysis and cluster analysis revealed three anthropogenic and also natural sources for heavy metals of the falling dust. According to the Ecological Risk Potential Index, Cd in 45. 10% of the samples was in a very high class and in 54. 88% of the samples was a high class. Pollution class of the ecological risk index of all the heavy metals was medium to high. The carcinogenic risk of Cr and Ba in children and adults was estimated to be higher than 10– 4. In both age groups, the Hazard index for each metal was less than 1 and its sum was measured as 1. 29 for children and 0. 16 for adults. Conclusion: Cd increases the ecological risk of the falling dust in the area. Ther heavy metal carcinogenic risk results showed that the concentrations of Cr and Ba were higher than standard. Also, the non-carcinogenic risk was higher in children than in adults.

The aim of this study was to assess the performance of Robinia pseudoacacia (black locust tree) to accumulation some of heavy metals and compared with the concentration of these metals in falling dust Yazd highway green belt. In order to an experiment was conducted as factorial based on completely randomized design with four replications. The results showed that the concentration of, iron, manganese, zinc, lead and cadmium metals in falling dust were the highest to the lowest, respectively. The distance from the highway in the concentration of heavy metals in leaves and bark of the black locust tree showed significant results (P<0. 01). Also, the effect of heavy metals in the leaves of this tree was higher than that of bark. Concentrations of manganese, cobalt, nickel and cadmium metals increased with increasing distance from the highway due to multi-directional winds and the presence of other contaminants. The Pearson correlation analysis between heavy metals found in the falling dust and Robinia pseudoacacia showed that the input and controlling factors of these metals in the black locust tree are probably the same as the dust. The results showed that the leaves of Robinia pseudoacacia with the amount of metal accumulation index of 4438 mg/kg has more ability to simultaneously absorb different metals. As a result, since this green belt surrounds Yazd urban area, it is hoped that a significant amount of heavy metals will be absorbed by these trees.

This research aims at studying the ability of Mondell pine tree )Pinus eldarica( in decreasing the heavy metal contaminants within the environment by determining the concentration of heavy metals in the leaves and bark of P. eldarica and comparing their concentrations with falling dust. After preparing the falling dust and plant samples, their heavy elements have been extracted by acid digestion method and then measured by flame atomic absorption spectrophotometry. The results showed that the concentration of iron, manganese, zinc, lead, and cadmium in falling dust were the highest to the lowest, respectively. Concentrations of cadmium, iron, cobalt, and nickel, increased with increasing the distance from the road due to multi-directional winds and the presence of other contaminants. The Pearson correlation coefficient among the heavy metals found in the falling dust and Mondell Pine tree showed that the input and controlling factors of these elements in the Mondell Pine tree are probably the same as the dust. The results showed that the P. eldarica bark with the amount of accumulation index of 7261 mg/kg has more ability to simultaneously absorb different metals. As a result, it is expected that significant amount of heavy metals will be absorbed by these trees in the green belt surrounds the Yazd urban area.