جستجوی مقالات مرتبط با کلیدواژه « آلودگی » در نشریات گروه « زمین شناسی »

This research aims to assess the concentration of potentially toxic elements (PTEs) in the soils around the Shahid Rajaei Combined Cycle Power Plant, located 25 km from Qazvin. For this purpose, 25 topsoil samples (0 to 10 cm) were collected, and after sample preparation, the physico-chemical parameters of the samples (including soil’s texture, pH, organic matter, calcium carbonate and cation exchange capacity) were measured. The concentrations of PTEs were determined using an ICP-OES device after strong acid digestion. The obtained results indicate that the average concentration of PTEs decreases in the following order: Mn > Zn > V > Cu > Cr > Pb > Ni > Co > As > Sb > Cd. Enrichment factor values showed that the studied soils are slightly enriched in Cd, Cr and Cu, and are significantly polluted with Pb, Sb, and Zn. Correlation coefficient values, cluster analysis, and principal component analysis show that Cu, Ni, Pb, and Zn are mainly from industrial activities, while As and Cd are probably entered into the soil through agricultural practice (i.e., application of chemical fertilizers and pesticides). Indeed, the highest concentrations of Cu, Ni, Pb, and Zn are recorded in the soil samples collected close to the power plant station in the downwind direction (S-N and NW-SE), indicating that the power plant activity is a possible source of these elements in the studied soils. The health risk assessment of PTEs indicates that As, Cr and Ni cause a cancer risk to children through ingestion. The carcinogenic risks of As, Ni, Cr, Pb, and Cd through all the three exposure routes are higher for children than for adults.

The main purpose of this study was to determine the concentration of water quality parameters and then the distribution of fluoride ion concentration in groundwater resources of KabudarAhang city located in Hamadan province; For this purpose, after sampling from selected wells and chemical analysis of relevant data, the concentration of water quality parameters for all wet and dry seasons of 2016, 2011, 2006, and 2020 were analyzed. According to the WQI classification, most water samples in the final years are in the weak range and for the years 2006 to 2011 are in the good classification range. Over the years, the effects of fluoride on human health have been recognized. Fluoride concentration in groundwater of Hamedan suburbs (KabudarAhang) for wet and dry seasons of 2020 was investigated using GIS software and WQI statistical index. The results of this study showed that in some areas of KabudarAhang, there is a possibility of exposure to natural pollution due to increased concentration of fluoride in drinking water. In general, 18.91% of groundwater samples have higher concentrations than the maximum allowable concentration of fluoride recommended by the World Health Organization (WHO) in drinking water. According to the proposed maps, the spatial variation of the studied parameter in groundwater was determined that the highest fluoride pollution is in the ideal route, located in the northwest of the region and Nodeh located in the southwest of the plain. The lowest fluoride concentration is in the northeast of the plain. The origin of this halogen group in the plains is due to geological factors, which is due to the country being located on the third fluoride belt in the world. In general, weathering and dissolution of gypsum, volcanic rocks, and calc-alkaline rocks cause an increase in fluoride levels in the groundwater of the area.

Mining is a necessary activity for the development of countries, but it imposes direct and indirect negative impacts on the exploited areas and their surroundings. Sangan iron mine is one of the largest iron ore deposits in the Middle East, where the ore is extracted by open pit mining. The present study aims to investigate the soil’s concentration of heavy metals and to assess the level of soil’s contamination in the Sangan mining area. For these purposes, 44 samples of the soils (including both topsoils and subsoils) of the Sangan mining area were collected, and were analyzed by an ICP-MS device. The obtained data were analyzed by calculating the geochemical indices and statistical methods. On the basis of descriptive statistics of the analytical data, Pb with an average content of 138.39 mg/kg and Cd with an average concentration of 0.19 mg/kg had the highest and lowest concentrations in top soils, respectively. Moreover, Cr with an average value of 102.19 mg/kg, showed the highest, and Cd with an average of 0.2 mg/kg showed the lowest concentrations in subsoils. The average concentrations of As, Cr and Fe in the study area were higher than their respective values in the World-Soil Average composition. Among the elements, Pb had very high and severe enrichment in two stations with enrichment factor values of 149 and 23.85. The results indicated no severe soil pollution and ecological risk in the study area, except in some sampling sites. The most polluted soils were collected near the placer extraction units and tailing ponds of Ehya-Sepahan Company, as well as the waste rock pile of Sanabad Comprehensive Development Industrial and Mining Company.

The present study aims to investigate the environmental geochemistry, source, and health risk of potentially toxic elements in urban soils of Shahrood, Semnan Province. For this purpose, the total concentration of major and trace elements in 26 topsoil samples was determined using an ICP-MS device. The average concentrations of As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb and Zn are 7.9, 0.1, 7.4, 77.5, 59.8, 448.9, 0.8, 31.5, 35.7 and 104.1 mg/kg, respectively. On the basis of the geochemical indices (i.e., enrichment factor, geoaccumulation index, single-factor analysis, nemerow integrated pollution index, and potential ecological risk index), the studied soils are polluted with potentially toxic elements, especially As, Pb and Cu, and the most polluted sites are located in the northern parts of the city. Statistical analyses (cluster analysis and principle component analysis) indicate that Co and Mn are mainly from natural sources, while Cr, Mo, Ni, Zn, Cu, As, Cd and Pb are probably from anthropogenic sources (especially industrial inputs and traffic). The health risk assessment shows that there is a non-carcinogenic risk of Pb for children through the ingestion route. The carcinogenic risk of As, Cr and Ni for children through the ingestion route is higher than the reference value (1×10-4). In conclusion, the pollution of the studied soils with As, Pb, Cu, Cr and Ni must be considered as a concern in the study area.

Issues related to air and aerosols have been one of the major environmental problems for the people of the world and the region in recent years. The present study was conducted with the aim of investigating suspended particles on the surface and vegetation of Khuzestanprovince in the period from 2000to2020.In this regard, in order to achieve the goal of the research, three aerosol optical depth products AOD,vegetation index product NDVI and land surface temperature product LSTwere used and the relationship between these parameters was investigated.The results obtained for the time period of the research show an almost similar general trend for all four periods.The results show that in the very low class, low AOD values ​​are associated with high vegetation values. For the low class, the area of ​​the AOD index has increased, but still the vegetation has a larger area percentage.
In the medium class, with the increase in the area of ​​the AOD index, the area value of the vegetation index has decreased greatly, and the area value of the average temperature class shows a slight increase. For the high class, the area value of the surface temperature index is higher than the AOD and vegetation indices. Finally, in the very high class,

In order to study the environmental characteristics of Semnan spas, water, sediment, and slime samples were collected. The concentration of Ag, As, Cd, Pb and Zn (0.7, 33, 0.4, 128.5, and 297 mg/kg, respectively) in the sediment samples are much higher than their respective values in mean crust and mean sediment compositions. The sediments are not enriched in Mo, Ni, Th, Co, Cr, Mn, Fe and U, while moderately enriched in Sb and Cu, significantly enriched in Cd, As, Zn and Pb, and highly enriched in Ag. The Bioconcentration Factor (BCF) values of As, Mn, Cu, Ni, Pb and Zn in slime samples are very high (1286, 2863, 2340, 1053, 1236, and 976, respectively). The water samples are classified as neutral-high-metal, and the concentrations of B, Li, Ba, Zn, Pb, Se, Cu, As, Ni and Mn in all samples are higher than their mean concentrations in unpolluted natural waters. The values of Contamination Degree (Cd) and Heavy Metal Pollution Index (HPI) in all samples are higher than 3 and 75, respectively, confirming the high level of pollution in the samples. The Water Hazard Index (WHI) values of the studied samples are lower than 5, indicating the non-toxicity of the target elements. The high concentration of potentially toxic elements in water, sediments and slime samples of Semnan Spa should be taken into account by people who use the Semnan spas for therapeutic purposes.

The Persian Gulf is an incredibly important and sensitive ecosystem that has garnered increased attention in the 21st century due to ongoing changes in international relations. There is an evident need for marine geological studies in this area, given the development plans, limited understanding of the seabed's geological condition, abundant oil resources, environmental concerns, and pollution of potentially toxic elements along the Persian Gulf's shores. The Persian Gulf holds a significant global importance as a water body with a delicate ecological balance. Given the sensitivity of the Persian Gulf and the detrimental impacts it endures from diverse polluting industries, environmental monitoring of this region is essential. This study presents a comprehensive analysis of geochemical changes, origin, and environmental and ecological risk assessment of potentially toxic elements in 140 sediment samples collected from the Iranian waters of the northeastern Persian Gulf.

We examined 140 surface sediment samples collected from varying depths of the waters under Iran's jurisdiction in the northeastern Persian Gulf during the MG-PG-2008 cruise. Our goal was to assess the level of contamination and ecological risk posed by elements such as As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V, and Zn. The concentrations of these elements in the sediment samples were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to provide a comprehensive understanding of their presence. Additionally, we quantified the pollution intensity in the sediments using indicators such as the geo-accumulation index (Igeo), enrichment factor (EF), and modified degree of contamination (mCd). Furthermore, we evaluated the ecological risk of potentially toxic elements in the sediment samples based on the potential ecological risk index (RI) and determined the toxicity risk of trace elements using the toxic risk index (TRI).

The sediment samples indicate significant enrichment of elements such as As, Cd, and Mo. Elements like Fe, Pb, Ni, Cr, and Mn fall into the medium enrichment category, while Cu, Zn, Ba, V, and Co are classified as having low enrichment. Comparatively, Fe, Ba, V, Zn, Pb, and Cu in the sediment samples show lower concentrations than their corresponding values in the upper continental crust. The enrichment factor (EF) values for these elements are less than 1.5, suggesting a terrestrial source for these elements. Additionally, the modified degree of pollution (mCd) values indicate very low levels of pollution at almost all stations.The ecological risk evaluation of potentially toxic elements in the surface sediments of the northeastern Persian Gulf reveals that Cd poses a medium ecological risk, while other elements exhibit a low ecological risk. The overall average ecological risk potential index (RI) at all sampling stations indicates a low level of ecological risk. Cd has the greatest influence on the ecological risk potential index, accounting for 61% of the total index, followed by As with 27%. The average toxicity risk index (TRI) suggests no toxicity risk, with Nickel being the most influential, contributing 52%, while Chromium has a 19% share.Notably, the significant enrichment of As and Cd in the northeastern Persian Gulf suggests their predominantly anthropogenic origin. This high concentration of arsenic may stem from the release of wastewater from urban and agricultural sources, various industries, gas and oil fields, and dust particles. Likewise, the presence of cadmium can be attributed to sources like oil tankers' transportation and industrial wastewater from factories.The significant correlation between aluminum, nickel, chromium, and vanadium (Al, Ni, Cr, V) indicates their terrestrial origin, mainly attributed to riverside erosion, weathering, and atmospheric precipitation. While the average enrichment of chromium and nickel can be linked to their high natural concentrations in the soil of southern Iran, industrial processes, including oil refining, can also contribute to their sediment concentrations.

The ecological risk assessment indicates medium-level risk for cadmium and low-level risk for other elements. The overall average potential ecological risk index (RI) suggests a low level of ecological risk across all sampling stations. The average toxicity risk index (TRI) indicates no toxicity risk, with nickel contributing the largest share (52%) followed by chromium (19%). Chromium and nickel concentrations in sediments are primarily of geogenic origin, evidenced by their strong correlation with aluminum. The average enrichment of these elements is attributed to their high natural concentration in the soil of southern Iran, although some man-made sources also contribute. The significant enrichment of As and Cd in sediments suggests their predominant human origin, possibly from wastewater discharge, industrial activities, and oil and gas fields. Cadmium in the Persian Gulf may originate from anthropogenic sources such as oil tanker transportation and industrial wastewater discharge.

In order to investigate urban soil areas of Isfahan for heavy metals, in the summer of 2022 from 23 sampling stations and after preparation, the samples were chemically analyzed by ICPOES method with 4-acid digestion. The soil accumulation index shows that CdA metals have a large consumption rate. The results of the enrichment factor of all metals indicated that the origin of all the metals except Pb, Cd, and As studied in the soil of urban areas was terrestrial and their accumulation was terrestrial. The pollution factor results showed the highest pollution factor for Pb and Cr metals. The results of the pollution load index showed that 8 samples have pollution and 15 samples have no pollution in the soil of the urban areas of esfahan. The results of the study of ecological risk and environmental risk of heavy metals showed that all the studied samples, except for 9 samples for Cd metal and 1 sample for Pb metal, have low ecological risk. Also, the findings of the study of the environmental risk index according to the values obtained for the soil of the urban areas of Isfahan showed that the environmental risk of heavy metals is low. According to the results, it was found that the risk potential of heavy metals in the soil of the studied areas to cancerous and non-cancerous diseases is higher in children than in adults.

A cultivation pattern in accordance with environmental conditions that reduces pollution of water and soil resources is one of the most important management strategies. This study aimed to simultaneously combine information related to soil, climate, crops and determine the potential of vulnerability and contamination of the aquifer, based on which susceptible cultivated areas (main cultivation -wheat and alfalfa) were evaluated. ArcGIS 10.3 software was used to investigate the effect of aquifer quality on cropping patterns. Climatic factors, soil parameters, and topographic characteristics were selected as effective parameters in selecting suitable cultivation sites. Nitrate content was collected in 46 wells in Shahrekord plain and averaged by kriging method, and a nitrate concentration map was obtained and combined with vulnerability map and aquifer quality area was investigated. Analytical Hierarchy Process was used to weight and finally, the layers were combined using the weighted linear combinationmethod. The results showed that areas without risk of contamination and with very low potential for contamination were 11 and 51%. Areas with low and medium to high risk of ontamination were 3 and 4%, respectively. About 25% of the aquifer area is in the high nitrate contamination range and its maximum nitrate concentration is 55 mg/l. Very high pollution (more than 75 mg/l) has not been estimated in Shahrekord plain aquifer. According to the results of this study, in terms of aquifer quality, the main part of the aquifer, about 41%, is in the safe range. 33% were classified in the low-risk group and 25% in the dangerous range. In Shahrekord plain, currently 4989 hectares are the area under irrigated wheat cultivation, which according to the results, can be increased to about 22,600 hectares. The current area under alfalfa is 3806 hectares, which according to the results, has the potential to increase the area under 28198 hectares.

Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic pollutants composed of two or more benzene rings. These compounds have attracted widespread attention due to their high carcinogenicity and mutagenicity in humans. In this study, 21 street dust samples were collected from various land uses in Kermanshah to investigate pollution and potential sources of PAHs. The samples were analyzed using gas chromatography-mass spectrometer (ICP-MS) after preparation. Also, in order to accurate identification of pollution sources, isomeric ratios were used. The results showed that all 16 PAH compounds identified by the United States Environmental Protection Agency (USEPA) as dangerous carcinogenic compounds are present in the street dust of Kermanshah metropolis. The concentration of total PAHs varies from 22.8 to 2820.98 μg / kg dry weight, with an average concentration of 1140.79 μg / kg. In addition, the toxic equivalency quotient (TEQ) in street dust samples of Kermanshah metropolis ranges from 18.54 μg / kg to 196.64 μg / kg, indicating the difference in concentration and toxicity of these compounds in different parts of the city. The results also show that the potential risk of carcinogenicity in adults and children through dermal contact is greater than direct ingestion and respiration pathways. In general, considering the isomeric ratios and principal component analysis, the combustion of fossil fuels, oil products and emissions from vehicles and traffic are the most important sources of PAHs in Kermanshah metropolis.

Acid mine drainage (AMD) as the most important environmental issue in mining sites is considered a significant source of environmental pollution.  AMD is typically produced by the oxidation of sulphide minerals, especially pyrite. The present study aims to investigate the acid production potential of the wastes of Mehmandoost coal washing plant located in NE Damghan. For this purpose, mineralogical, geochemical, and statistic tests were carried out on 7 representative coal washing waste samples. The obtained results show that although coal washing wastes are not enriched in Cu and Mn, they are moderately enriched in Ni and Co, significantly enriched in Cr, Sb and Zn, strongly enriched in Cd and As, and extremely enriched in Pb and Mo. The main mineral phases presented in the studied samples include quartz, muscovite, clinochlore, kaolinite, illite, montmorillonite, calcite and pyrite. In most of the studied samples, the pH and electrical conductivity (EC) of the saturated paste is <3 and > 2000 μm/cm, respectively. Moreover, in most samples the Net Neutralization Potential (NNP) is < -20. Also, in most of the samples, the Net Acid Production Potential (NAPP) is positive and the Neutralization Potential ratio (NPR) is < 3. The pH of Net Acid Formation (NAG pH) of these samples is < 4.5 and the ratio of Acid Neutralization Capacity to Maximum Acid Potential Acidity (ANC/MPA) is < 1. According to the results of static tests, there is a possibility of production of acidic drainage by the studied samples, therefore, taking suitable management measures to control acid production in the area is of crucial importance.

This study was conducted to investigate the heavy metal contamination and their region in Jafar Abad, southwest of Kashmar in Khorasan Razavi province. For this purpose, heavy metals of surface soil samples 32 (10- 30 cm) were analyzed in the Jafar Abad, southwest Kashmar by ICP-MS origin indices and degree of contamination including enrichment factor (Ef) and its percentage, geoaccumulation index (Igeo), contamination factor (Cf) were calculated to evaluate soil contamination. Based on the results, in between heavy metals, Manganes has the highest and Cadmium the lowest average contamination. Maximum and minimum enrichment factors are also Molybdenum and lead respectively. The results show that the study area is almost contaminated with respect to copper and molybdenum metals. The results of this study indicate that heavy metals contamination is lithogenic and mainly due to the lithology of the region such as shale, sandstone, conglomerate, gypsum marls, granite and volcanic rocks, and anthropogenic contaminants, except from limited mining activities and some agricultural activities did not play a significant role in the contamination of this region. Based on cluster analysis and principal component analysis, the presence of some metal such as copper, molybdenum and manganese together indicates their common origin.

The study area is located in Chaharmahal and Bakhtiari province and includes Shahrekord and its villages. The highest outcrop of the region is related to the Mesozoic limestone formations in which the Upper and Lower Cretaceous limestones have the largest extent, and Precambrian sediments have a limited extent. The existence of different age facies along with mining, industrial, and agricultural activities can provide the necessary grounds for soil contamination with heavy elements. In the present research, considering the importance of soil health from the perspective of environmental geochemistry, the presence and distribution of these elements in the region’s soil were investigated. The present study aimed to determine the distribution of heavy metals based on zoning maps of elements and the correlation between them in the soil environment.

For this purpose, the results of the chemical analysis of 61 soil samples were taken from a depth of 0-25 cm (after removing surface contaminants). The concentration of heavy metals was analyzed using the ICP-MS method in Zarazma Company and was evaluated and interpreted using multivariate statistical methods. Also, geoaccumulation index (Igeo), Nemerow integrated pollution index (NIPI), pollution index (PI), and enrichment factor (EF) of elements were calculated.

The average concentration of total heavy elements in the soils of the study area was 4.39, 13.34, 91.82, 32.18, 70.57, 11.70, and 81.64 for arsenic (As), cobalt (Cb), chromium (Cd), copper (Cu), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn), respectively. The average concentration of heavy metals in the surface soil of Shahrekord for different elements was in the following order: As

Therefore, there is no significant environmental concern. This result is in line with the results of the present study. In all sampling sites, the PI is in the allowable category. Besides, the concentration of heavy metals such as Pb, Zn, and Cu is less in the soil of Shahrekord than in the soil of other cities, but Ni has a higher concentration. Also, since the EF was less than 10 for the study area’s soils, these elements’ natural or geogensis origin is confirmed

The tectonic depression Urmia Lake in the northwest of Iran is receiving a lot of erosional sediments of the geological structures and waste materials of the industrial, mining and agricultural activities. Fifteen surface samples including sandy and muddy sand sediments of the studied area have selected and analyzed by ICP. Based on average values of heavy metal concentration the ranking of intensity of heavy metal pollution of the studied area sediments is as follows: Al> Fe> Mn> Ba> Cr> Ni> Zn> Cu> Co. The concentrations of Ni, Mn and Cr are much higher than Consensus-based PEC (probable effect concentration) and Iran Standard (especially in south and southwest sites of the lake) that display very high probability of the harmful biological and environmental effects of heavy metal in these sites. the mean concentration EF in the studied sites displays industrial and mining effects in enrichment of the heaviest metals especially Ni, Cr and Cu (moderate to moderately severe enrichment) in the south and southwest transects and Cu (moderately severe) in the Jabal transect. the mean contamination factor value display considerable enrichment for Ni, Cr and Cu and partly for Mn especially in south and southwest transects. The modified degree of contamination for all of transects with the exception of the Jabal Kendy site in the southwest lake that have moderate contamination, displays low contamination. Geoaccumulation index for all of transects displays no to moderate enrichment. In general, concentration of the toxic metals of the studied sediments displays low biological hazard (except for Cu and Ni).

Due to increasing urbanization and industrial development, environmental pollution has increased and heavy metals are one of the most groups of pollutant. Sediments act as indicators of heavy metal in coastal environment, they are the main reservoir of heavy metals. Inorder study about environmental pollution and the andemic species, sediments and T. mutabilis samples were collected from 5 transects (South Golshahr, Khaje Ata, Posht-e- shahr, Jahanbar rahe Se, Soro) of the Bandar Abbas (NE Persian Gulf) in cold and warm season, and the metal concentrations were determined for them. Metals contents were analyzed by using ICP-MS. Statistical analysis was performed with SPSS 18.0 software. The highest amount of metals belongs to Fe, Al, Mn in warm and cold season. Sediment quality was measured by Contamination Factor. Cd, As, Hg, Zn, Cu & Pb levels in sediments from all transects higher than the recommended values of standard (USEPA ,1996; ROPME, 2003).

Mashalak River is located in the north of Iran and is one of the most important rivers leading to the Caspian Sea west of the Mazandaran province. To conduct environmental monitoring, 25 samples of sediments were collected from the Mashalak riverbed. The samples were analyzed by ICP-MS. A review of heavy metal concentrations suggested that the highest concentrations of heavy metals pertained to Vanadium, Chromium, Zinc, Nickel, Copper, Lead, Cobalt, and Molybdenum, respectively. According to Sediment Quality Guidelines (SQGS), Mashalak sediments are more likely to be contaminated with Chromium and Nickel. The enrichment index shows that Chromium and Nickel produce moderate pollution while other metals have low pollution. Using the Geo-Accumulation Index, only Chromium shows low to moderate pollution. Examining the ecological risk of heavy metals in the Mashalak River deposits suggests these deposits are not contaminated, indicating that the ecological risk of the area under study is low. The Principal Component Analysis (PCA) test results helped identify two main factors. The main factor includes such metals as Cobalt, Aluminum, Vanadium, Copper, Nickel, Zinc, and Chromium, which have both lithogenic and anthropogenic origins simultaneously, as the secondary factor includes the former.

In recent years, the long period of droughts and dust storms have caused dust particles to enter the west of the country. The large population, development of industrial centers and the existence of various sources of urban pollutants may increase the pollution load of dust particles in Kermanshah Metropolis. In this study, concentration of six heavy metals (Cd, Cr, Cu, Pb, Zn, and Ni) was investigated in street dust of this city. For this purpose, 21 street dust samples were collected and analyzed by ICP-MS. The results showed high concentrations of Cd, Cu, Pb and Zn with a mean values of 0.34, 128, 98.71 and 282.24 mg/kg, respectively. Enrichment factor, pollution load index, potential ecological risk index and health hazard index were used to investigate the contamination level of dust particles. The results of these indices indicated relatively high levels of lead, zinc, copper and cadmium in most parts of the city. Also, 42.85% of the sampling sites have low ecological risk index and 52.30% of the stations show moderate risk index. The highest hazard quotient (HQ) was calculated for the ingestion pathway, particularly for Cr and Pb. However, the risk index values for all the studied heavy metals were below unity for children except for lead in three stations. Principal component analysis (PCA) showed that chromium and nickel were predominantly originated from geogenic sources and other elements were highly affected by anthropogenic sources.

The pollution of heavy metals not only affects directly the physical and chemical features of soil and reduces biological activities and access to nutrition materials in soil, but also is considered a danger for human health. The finding from geo-accumulation index of serpentine soil samples shows that the intensity of serpentine soil is classified in the range of no pollution to average regarding chromium and nickel. In addition, the pollution bar index of chromium and nickel is more than 1 proving the inappropriate soil quality and soil pollution of the region. However, nickel has the most considerable value. The average value of EF proving the region shows enrichment for the chromium and nickel elements. According to the Pearson correlation coefficient, there is a high correlation between cobalt, chromium, and nickel that indicating the equal source or similar geochemical behavior of the elements toward each other. According to the geostatistics values such as geo accumulation, enrichment factor, and pollution bar in the studying area, is pollution in nickel and chromium elements. Pearson correlation coefficient reveals that there is a high correlation among cobalt, chromium, and nickel proving the same origin. Making a zoning map of heavy metal density in the region soil demonstrates that the high density of the elements in some stations is related to geological factors. Cluster analysis shows the division of the elements into 7 clusters. Besides, the elements with the structural relationship are related in the next subcategories. Clusters 6 and 7 together indicate the same origin for these elements.

This study was conducted to investigate the heavy metal contamination and their origin in eastern Azna city in Lorestan province. For this purpose, heavy metals of surface soil samples 113 (5-15 m) were analyzed in the eastern Azna city by AAS flame atomic absorption spectrometry. Origin indices and degree of contamination including enrichment factor (Ef) and its percentage, Geoaccumulation Index (Igeo), contamination factor (Cf) were calculated to evaluate soil contamination. Based on the results, the mean concentrations of heavy metals including Zn, Y, V, Sn, Sr, Sc, Pb, Ni, Cu, Cr, Cd, B, Br were 86.9, 51, 161, 14.5, 160, 26, 32.6, 65.4, 34, 22.9, 0.7, 102, 393 mg/kg, respectively, which Br has the highest and Cd the least. Maximum and minimum enrichment factors are also Cd and Br, respectively. The results showed that the studied area is not heavily contaminated with heavy metals but the concentration of some metals is very high in some places and in the case of a natural source of contamination (rock and soil), these sites can be used as potential mining and resource sources.