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The increase in pollution resulting from industrialization and urbanization has become an important concern in developing countries owing to its impact on human health. Therefore, in the present study, to investigate the pollution, 70 street dust samples were collected from medical centers in Yazd and in the laboratory to determine the content of Fe, Co, Mn, Zn, Pb, Cr, Cd, Ni, Cu, As and Al was digested using induction spectroscopy. The spatial pattern of the metal concentration was prepared using the Inverse Distance Weighted (IDW) interpolation method in GIS software. Pairwise correlation between metals was performed using Pearson's correlation, and classification of similar metals in terms of possible origin was performed using hierarchical clustering. In addition, the pollution level was determined using the enrichment factor, geo-accumulation index, pollution index, and integrated pollution index. According to the results, the trend of the average concentration of metals is Fe (23587.16), Al (18074.94), Zn (602.54 mg/kg), Mn (445.7 mg/kg), Pb (80.95 mg/kg), Cu (60.86 mg/kg), Cr (46.83 mg/kg), Ni (34.09 mg/kg), Co (10.2 mg/kg), As (0.29 mg/kg), and Cd (0.21 mg/kg). Based on the spatial distribution pattern, the highest concentrations of metals were observed in medical centers near the two-way street and single-line station. The highest amount of enrichment was observed for Zn, and as a result, a class of high enrichment was observed. The highest values of the soil accumulation index, degree of pollution, and uniform pollution were related to Zn and Pb. A significant correlation was observed between-Al and Fe Co--Mn Cr, Cd-Cr-Pb, and Ni-Cu elements at the 1% level, while As did not correlate with other elements. Based on the hierarchical clustering of elements, Co, Mn, Cr, Cd, Pb, Ni, Cu, and Zn were of human origin, while Al and Fe were of natural origin. [ABSTRACT FROM AUTHOR]

Due to various activities, heavy metals can be released in the environment and endanger the health of people in the society. Considering the importance of the subject, the present research has investigated the contamination of Araghi catchment basin sediments with heavy elements. For this purpose, 24 sediment samples were collected and the concentration of 11 heavy elements, including arsenic(As), cadmium(Cd), cobalt(Co), chromium(Cr), copper (Cu), iron (Fe), Molibden(Mo), nickel (Ni), lead(Pb), vanadium (V)and aluminium(Al), were studied and pollution indicators were used to measure pollution. Based on the calculation of the enrichment index and according to the classification of Chen (2007), Mo (with an average of 0.91), Cu (with an average of 0.92) and Fe (with an average of 0.96) are among the elements without enrichment (less than 1) and the elements of Pb, Cr, As, Ni, Co and V are in the slightly enriched range in the region. Based on this index and the Anthropogenic Percent, the origin of all the studied elements is in the lithogenic area, which is caused by the weathering and erosion of the rock units of the area. The results of examining the Contamination factor, Modify Contamination Degree, Pollution Load Index and Geoaccumulation Index showed that the sediment samples in the study basin did not show any specific pollution and were classified as non-polluted. The average Ecological Risk index and Modified ecological risk index were obtained as 50.38 and 114.07, respectively, which according to Hakanson's classification, the state of Ecological Risk index and Modified ecological risk index of sediments in the studied area are low for heavy elements. [ABSTRACT FROM AUTHOR]

The rapid development of industry and economy has led to the entry of environmental pollutants, particularly heavy metals, into the soil, raising concerns among the global community regarding public health and food security. Consequently, the awareness and assessment of these elements have become significant in predicting hazards and related diseases, as well as establishing soil quality standards. This study aimed to quantify lead (Pb) contamination using various environmental indices in a part of Shahr-e-Ray, Tehran Province. To achieve this, 44 composite soil samples were collected from the 0-20 cm soil depth. After sample preparation, some physical and chemical properties were measured using standard methods, and the total concentration of lead in the soil was determined using the Aqua Regia method. Three environmental indices, including the Enrichment Factor, Geoaccumulation Index, and Contamination Factor, were employed to assess the potential risk of lead contamination. The results indicated that all examined samples exceeded the standard and recommended limit for lead concentration in Iran, with an average of 135.99 mg/kg. In term of the Geoaccumulation Index, the samples exhibited a range of (2.46-2.90), categorizing them in the moderately to heavily polluted class. For the Enrichment Factor, all samples fell into the high enrichment class, with a range of (6.48-9.31). The Contamination Factor also classified the samples as highly contaminated, with a range of (8.25-11.24) which is mainly influenced by human activities. Continuous monitoring and surveillance of lead concentration variations in the studied soils are essential for preserving production resources and achieving food security. [ABSTRACT FROM AUTHOR]

Introduction: Rivers are considered as a vital resource for mankind from the past to the present day.Considering the ever-increasing population, industrial developments and the expansion of modern urban societies, it is expected that the rivers located near densely populated urban and rural areas to be in danger of destruction due to a large part of urban, rural, domestic, industrial and agricultural pollutants to the sources of surface and groundwater in the riparian and riverside more than any other water ecosystems. On the other hand, regarding Iran's arid and semi-arid climate, the use of sediment qualitative indicators in research and investigation is crucial in order to predict, evaluate and provide a sustainable solution for controlling the amount of pollutants and also improving the quality of river water. The Karaj River is one of the main freshwater and energy production resources in the region, which plays a vital part in creating an ecological balance in parameters affecting the quality of this water ecosystem. The purpose of this research is to measure the concentration of heavy metals in the sediments of the river bed and to evaluate and analyze it using Geoaccumulation index and Enrichment Factor, which led to the suggested solutions in order to avert and control the further spreading of pollution.Material and Methods: In this research, nine stations were selected based on the land use of the area. The sediments of the river bed in each station were sampled. Sediment samples were prepared and later transferred to the laboratory and the total concentration of heavy metals was measured by Inductively Coupled Plasma Mass Spectroscopy (ICP) device.Results and Discussion: The results obtained from the measurements using the mentioned indices assessed that the level of heavy element pollution is relatively low in the Karaj River. Nevertheless, part of this slight pollution is related to human activities such as road construction, tourism and the leakage of local runoff and sewage into the river and its riparian zone, which led to the increase of the Geoaccumulation of elements including copper and chromium to the numbers of 1.01 and 1.96 in downstream stations P8 and P9, respectively. Also, the highest average amount of Geoaccumulation for copper in 9 sampling stations was 0.23. On the other hand, these anthropogenic activities have significantly increased the arsenic Enrichment up to 17.81 in station P4 and the average Enrichment Factor of Arsenic in 9 sampling stations up to 13.12. But since each heavy element has its own unique nature, part of the quantity of the pollution present in the sedimentary environment of the river is related to natural factors, geology, soil erosion and weathering of riverbed rocks.Conclusion: The process of changes in the amount and distribution of elements in the sediments were compared and the factors affecting their alignment or mismatch were discussed and researched. Generally, the results of this research show that the Karaj River, taking into account the Geoaccumulation index and Enrichment Factor, has negligible contamination of heavy metals in the riverbed sediment. However, the trend of index changes along the river route shows the direct effects of destructive human activities in the region.

Introduction: Rivers are considered as a vital resource for mankind from the past to the present day. Considering the ever-increasing population, industrial developments and the expansion of modern urban societies, it is expected that the rivers located near densely populated urban and rural areas to be in danger of destruction due to a large part of urban, rural, domestic, industrial and agricultural pollutants to the sources of surface and groundwater in the riparian and riverside more than any other water ecosystems. On the other hand, regarding Iran's arid and semi-arid climate, the use of sediment qualitative indicators in research and investigation is crucial in order to predict, evaluate and provide a sustainable solution for controlling the amount of pollutants and also improving the quality of river water. The Karaj River is one of the main freshwater and energy production resources in the region, which plays a vital part in creating an ecological balance in parameters affecting the quality of this water ecosystem. The purpose of this research is to measure the concentration of heavy metals in the sediments of the river bed and to evaluate and analyze it using Geoaccumulation index and Enrichment Factor, which led to the suggested solutions in order to avert and control the further spreading of pollution. Material and Methods: In this research, nine stations were selected based on the land use of the area. The sediments of the river bed in each station were sampled. Sediment samples were prepared and later transferred to the laboratory and the total concentration of heavy metals was measured by Inductively Coupled Plasma Mass Spectroscopy (ICP) device. Results and Discussion: The results obtained from the measurements using the mentioned indices assessed that the level of heavy element pollution is relatively low in the Karaj River. Nevertheless, part of this slight pollution is related to human activities such as road construction, tourism and the leakage of local runoff and sewage into the river and its riparian zone, which led to the increase of the Geoaccumulation of elements including copper and chromium to the numbers of 1.01 and 1.96 in downstream stations P8 and P9, respectively. Also, the highest average amount of Geoaccumulation for copper in 9 sampling stations was 0.23. On the other hand, these anthropogenic activities have significantly increased the arsenic Enrichment up to 17.81 in station P4 and the average Enrichment Factor of Arsenic in 9 sampling stations up to 13.12. But since each heavy element has its own unique nature, part of the quantity of the pollution present in the sedimentary environment of the river is related to natural factors, geology, soil erosion and weathering of riverbed rocks. Conclusion: The process of changes in the amount and distribution of elements in the sediments were compared and the factors affecting their alignment or mismatch were discussed and researched. Generally, the results of this research show that the Karaj River, taking into account the Geoaccumulation index and Enrichment Factor, has negligible contamination of heavy metals in the riverbed sediment. However, the trend of index changes along the river route shows the direct effects of destructive human activities in the region. [ABSTRACT FROM AUTHOR]

Background: Heavy metal pollutants in rivers are one of the serious environmental concerns in aquatic ecosystems. Sediments, as an environmental indicator, have an acceptable ability to express the degree of environmental pollution with heavy metals. Therefore, with the aim of evaluating the health of the water ecosystem of Zayandeh Rood, we investigated pollution using sediment indicators. Methods: In this study, the sediments of Zayandeh Rood River were sampled at 17 stations. Metals lead, zinc, iron, cadmium, cobalt, nickel, copper and chromium were measured by acid digestion method with atomic absorption device. Also, land accumulation indices, Nemerow pollution index and ecological risk potential were calculated. Results: The average concentration of metals in sediments is 1762.92 iron, 201.52 nickel, 44.07 zinc, 23.36 cobalt, 28.67 copper, 11.51 lead, 10.09 chromium, and 0.87 cadmium mg/kg. According to the Igeo index, the average concentration of chromium, iron, copper, zinc and lead elements in all stations was lower than the average of the earth's crust, and the concentration of nickel and cadmium in all stations was higher than the background value. In all stations, the ecological risk potential index of cadmium was higher than other elements. Conclusion: Considering the condition of river sediments in terms of cadmium and nickel pollution and their very high ecological risk, it is necessary to comprehensively monitor the river and its living organisms. Also, in order to evaluate its health and ecological risk with the approach of examining the trend of spatial and temporal changes, heavy metal pollution in water and river sediments should be taken into consideration.

Background and Objective: Today, soil and water pollution with heavy metals is one of the major challenges around the world. The aim of this study is to investigate the contamination of soils around a lead and zinc mine. Materials and Methods: In the summer of 2019, 100 soil samples were taken from the mine vicinity and the characteristics of texture, acidity, salinity, calcium carbonate, organic matter and heavy metals chromium, cobalt, zinc, lead and cadmium were measured. Pollution indices including pollution factor (PI), enrichment coefficient (EF), geoaccumulation (Igeo), toxicity probability (MERMQ), contamination load (PLI), background enrichment (PIN), pollution security (CSI) and Nemerow index (PINemerow) ) Were calculated. Correlation between soil variables and determination of metal origin were determined using Pearson correlation and principal component analysis (PCA) analysis. Results: The average concentrations of chromium, cobalt, zinc, lead and cadmium were obtained as 92, 21.33, 453.98, 351.24 and 4.28 mg/kg, respectively. The metals pollution evaluated based on PI, EF and Igeo indices were moderate for chromium and cobalt, considerable for zinc and significant for lead and cadmium. The results of MERMQ, PLI, PIN, CSI and PINemerow indices showed high soil contamination with heavy metals. According to the PCA test, the elements lead, zinc and cadmium are in a group with high correlation with each other that are of anthropogenic origin. Chromium and cobalt with a correlation of 88% also showed the same geological origin. Conclusion: mining activities should be done with more caution and measures should be taken to reduce pollution.

Background and Objective: Today, soil and water pollution with heavy metals is one of the major challenges around the world. The aim of this study is to investigate the contamination of soils around a lead and zinc mine. Materials and Methods: In the summer of 2019, 100 soil samples were taken from the mine vicinity and the characteristics of texture, acidity, salinity, calcium carbonate, organic matter and heavy metals chromium, cobalt, zinc, lead and cadmium were measured. Pollution indices including pollution factor (PI), enrichment coefficient (EF), geoaccumulation (Igeo), toxicity probability (MERMQ), contamination load (PLI), background enrichment (PIN), pollution security (CSI) and Nemerow index (PINemerow) Were calculated. Correlation between soil variables and determination of metal origin were determined using Pearson correlation and principal component analysis (PCA) analysis. Results: The average concentrations of chromium, cobalt, zinc, lead and cadmium were obtained as 92, 21.33, 453.98, 351.24 and 4.28 mg/kg, respectively. The metals pollution evaluated based on PI, EF and Igeo indices were moderate for chromium and cobalt, considerable for zinc and significant for lead and cadmium. The results of MERMQ, PLI, PIN, CSI and PINemerow indices showed high soil contamination with heavy metals. According to the PCA test, the elements lead, zinc and cadmium are in a group with high correlation with each other that are of anthropogenic origin. Chromium and cobalt with a correlation of 88% also showed the same geological origin. Conclusion: mining activities should be done with more caution and measures should be taken to reduce pollution. [ABSTRACT FROM AUTHOR]

Introduction: Soil is a hardly renewable natural resource. Although soil degradation, caused by either human activities and natural processes is a relatively slow procedure, but its effects are long lasting and most often, irreversible in the time scale of man's life. Among the most significant soil contaminants resulting from both natural and human sources, heavy metals are more important due to their long- term toxicity effects. For evaluating soil's enrichment rate by heavy metals, a wide and full study of soils background values, including total and available fractions of heavy metal contents should be done. Zanjan province has some great mines and concentrating industries of lead and zinc especially in Angoran, Mahneshan. Unfortunately produced waste materials of these industries spread over the adjacent areas. Investigations showed that accumulation of some heavy metals in vegetables and crops planted in this region had occurred. Therefore, performing some investigations in these polluted areas and assessing pollution rate and heavy metals distribution in arable lands had prime importance. Our goals were: 1) determining the total and available amounts of Cu, Pb, Zn and Cd in the soils of arable lands in polluted areas of Zanjan city, 2) producing the distribution map for the metals mentioned above and 3) calculating pollution indices in the soils. Materials and Methods: The study area was in south west of Zanjan city. For soil sampling, a 1 Km by 1 Km grid defined in ArcGIS software on landuse layer and totally 144 points that placed on agricultural lands, due to our goals, were sampled. For sampling, in a 5m radius around the point we collected some subsamples from depth of 0 - 15 cm, and after mixing the subsamples, finally a 1Kg soil sample prepared and sent to the laboratory. Sampled soils were air dried and were passed through a 2mm sieve. Soils organic matter (OM) content and texture were determined by Walkely-Black and Bouyoucos hydrometer methods, respectively. Soils pH were determined by glass/calomel electrode in saturation paste, EC by EC-meter in saturation paste extract, and calcium carbonate equivalent (lime) by reverse titration method. Total and available amounts of Zn, Cu, Cd and Pb were extracted by Aqua- Regia method (wet oxidation by chloridric acid and nitric acid with the 3:1 ratio) and by DTPA extracting solution, respectively. After extracting and filtering liquid samples, metal concentrations were measured by atomic adsorption method using GBC avanta P. Statistical analysis by SPSS and indices calculation by Excel were performed, and distribution maps were prepared by Inverse Distance Weighting method in ArcGIS software. For evaluating pollution rate, Geoaccumulation index, Enrichment factor and Availability Ratio indices were calculated and interpreted. Results and Discussion: The textures of soil samples were loam, clay loam and sandy loam. The OM contents of almost soils were less than 2 percent. Lime was less than 25 percent and acidity of soils were neutral to slightly alkaline. Soils salinity were less than 2 dS/m except a few samples. Accordingly, these soils were suitable for agriculture and there were no limitation due to evaluated properties. Median values for the total concentrations of Cd, Cu, Pb and Zn (extracted by Aqua Regia) were 0.5, 22.5, 14 and 82.3 mg/Kg of soils, respectively, and for available fraction (extracted by DTPA) were 0.1, 0.9, 1.6 and 3.2 mg/Kg of soils that were much lower than measured total values. According to 90th percentile of geoaccumulation index, at least 10 percent of samples had been polluted with Zn, Pb and Cd. Enrichment factor revealed no long term pollution. Availability ratios of Pb and Zn were relatively high, showing there exists unique and recent pollution source for them. All pollution indices showed positive correlations with OM content of soils (except for availability ratios of Cd, which had negative correlation). Therefore, OM content of soils were respect to control these indices. Geoaccumulation index of Zn, Cd and Pb, and availability ratios of Zn and Pb showed negative correlations with soil pH. Therefore, in some seasons of the year, their availabilities will increase in soil. Conclusion: The results showed that Cu content in soils were not in the critical limit but Cd, Pb and Zn content in soils were greater than standard levels and reclamation procedures for remedy of these soils must be done. The high values of the heavy metals in available fraction inthe soils increased the risk of bioaccumulation in microbial and biotic tissues. In areas where there are high content of available form of heavy metals in soils, it could be an index of new contamination in soils by heavy metals. According to geoaccumulation index of Cd, Zn and Pb, there are some contaminated points around waste depositition areas near Zanjan city. These points are in the direction that wind could effectively transport the particles of wastes to urban area. Enrichment factor (EF) showed that at least there were a few points polluted by Cd, Zn and Cu, although EF values were generally low. The leaked wastes of Zinc and lead industries had been spread in deposited areas caused difficulties in determining background values for the selected metals.

Background and Objective: Street dust is considered as one of the important sources of particulate matters and heavy metals in the atmosphere. The goal of this study was to assess the heavy metals pollution in street dust of Tehran and evaluate their ecological risk. Materials and Methods: The sampling of street dust was carried out in two areas at the east and west of Tehran. After preparation of samples, the concentration of heavy metals was measured by ICP-MS. The pollution level of heavy metals in the street dust was assessed using geoaccumulation index (Igeo), pollution index (PI), integrated pollution index (IPI), enrichment factor (EF) and ecological risk index (RI). Results: The results of the calculations of the indices showed that the street dust in both studied areas was non-polluted with Li, Al, Ti, V, Cr, Mn, Fe, Ni, Sr and Ba. The origin of these elements was mainly natural sources. However, Cd, Cu, As, Zn, Sn and Pb had medium to high level of contamination. These elements had a very high to extremely high enrichment in both areas. Their origin was mainly anthropogenic sources. The ecological risk index indicated a moderate ecological risk for the east and a low ecological risk for the west area. Conclusion: The higher level of lead in the East is the main reason of higher ecological risk of this area. Therefore, the heavy metals pollution of the street dust, especially lead and its enterance into the environment, should be considered in this area. [ABSTRACT FROM AUTHOR]