Heavy metal influx to the agricultural soils, became of great global concern due to risks to the human health and environment, The aim of this study is to investigate heavy metal concentrations in the rice farms of Ahwaz and Bavi counties in Khuzestan province, and determine anthropogenic or natural sources of heavy metals, using statistical methods. 14 farms were chosen in Ahwaz and Bavi counties. Soil physicochemical measuremnts showed that PH of soil in rice farms has a slightly alkaline to alkaline. Average concentration of Ag, As, Cd and Sb is higher than that of standard crust. Based on average environmental risk assessment indices the highes contamination was related to Ag, As, Cd and Sb, which indicates the anthropogenic input to agricultural soil such as using pesticides and chemical fertilizers in the study area. Statistical analyses showed that Cr, Fe, Pb, Ni, and V have a natural source, Sb and Cd anthropogenic source and As and Mo both anthropogenic and natural sources and Ag anthropogenic source. Bioconcentration Factor value for Mo was close to 1, so plant is considered as an indicator of this metal, BCF for other metals was low. Health risk due to As and Pb is probable through rice consumption and in with the consumption of vegetables, fish and other foods containing heavy metals. The highest mean concentration of metals in rice sample was mensured for Pb and the lowest for V. Pb concentration in rice sample was higher than WHO standard, and As concentration was close to the WHO standard. Non- corcinogenic risk for adults and children due to As and Pb was medium and for Ni, Cr and Hg was low. Health index for metals was low and long-term adverse effects is possible.

Many clinical cases of mineral deficiency, specially associated with Copper and Zinc in sheep of Khuzestan province observe annually. The aim of the present study was to investigate the elemental status (Cu, Mo,Fe, S, Zn) of soil and pastures forages in order to see the probable correlation of these elements with Copper and Zinc in serum of sheep in Susngerd area. 5 soil, 5 forage samples, and 50 blood samples were taken. Soil and forage samples after preparation in laboratory were sent to Zrazma laboratory. Blood samples were sent to the institute of radiation at atomic energy organization of Iran for the elements measurement. The soil samples were analyzed by ICP-OES. Forage samples were by ICP-MS apparatuses. Serum levels of copper and zinc were also measured by atomic absorption spectroscopy. PH and organic matter were measured using standard methods. The statistical methods used in this study to analyze the data are the correlation coefficient and principal component analysis which were performed using the software SPSS20. Principal component analysis are used to determine the probable origin of metals (anthropogenic and geogenic) and correlation coefficient to determine the association between different metals. Soil sample analyzes results showed that the averages iron and sulfur content of soil were higher than international standard and critical levels, while the averages copper and molybdenum were within normal range. The mean concentration of zinc in soil samples was lower than critical level. Comparing the mean values of forage elements with their critical levels showed that sulfur and iron were higher than standard levels, while, the mean concentration of Cu, Mo, and Zn in forage samples were in normal range. The mean value of Cu/ Mo in forage samples was 19.7, that is in normal range. The results revealed that the serum copper and zinc were lower than normal and sheep under this investigation were mostly in a borderline deficiency status. It seem that high levels of sulfur and iron in pastoral forages reduces intestinal absorption and bioavailability of copper and zinc in sheep grazing in the under study areas. In order to evaluate metal pollution, various indicators, including coefficient of ecological risks, contamination factor, the degree of contamination, and the enrichment factor were used. Ecological Risk factor for copper, molybdenum and zinc for the whole region is low. The ecological risk index for the whole region is also low. Contamination factor values for copper, molybdenum, zinc and iron in all areas is low. Contamination factor values for sulfur in all areas of is very high. The degree of contamination is very high in all the region in the area. Enrichment factor results showed copper, zinc and iron, without enrichment, molybdenum enrichment is low and sulfur enrichment is severe.  Pearson correlation coefficient indicates that copper and zinc, copper, iron, zinc and iron have a high positive correlation. The principal component analysis has provided three main components. The first component (Cu, Zn, Fe) derived from geogenic source, the second component (Mo) has both anthropogenic and geogenic sources, and the third component (S) has both anthropogenic and geogenic sources

The present study was conducted to evaluate the correlation between element concentration (copper, sulfur, iron, molybdenum and zinc) in soil and pastoral forages with copper and zinc in serum levels of sheep in MasjedSolaiman. For this purpose 4 soil , 4 forage and 60 blood samples (15 samples from each area) were taken. Serum samples were analysed usig Atomoc absorption, Soil samples using ICP-OES and forage sample using ICP-MS. Also pH level and organic matter contents of soil sample were determined using standard methods. The mean concentration of sulfur, Iron, molybdenum, zinc and copper contents of soil samples were 6892± 130, 17772.2± 5489, 0.96± 0.15, 48.75± 13.3 and 19± 4.5, mg/kg respectively. Comparing of these concentrations with international standard and similar researches showed that all of the elements are within normal limits except iron and sulfur that showed higher levels than critical level.
Comparing the mean values of forage elements with their critical levels and other studies, showed that the mean values for sulfur, copper, molybdenum and zinc in the forage samples in the under study areas were in normal ranges. In this study, the mean ratio of copper to molybdenum in forage was 29.6.
The results revealed, although copper content of forage samples was in the lowest normal value (6.2 ± 1.5 mg/kg), because of normal sulfur and molybdenum amounts in soil and forage, copper deficiency was not observed in sheeps. Comparing to normal values, due to high content of soil and pasture iron and decrease in zinc bioavailability, serum zinc concentration of sheep under this investigation was mostly in a borderline deficiency status.
Contamination factor values for Cu, Zn,and Mo in the study area are low and very high for sulfur in the AbAnjirak and Golgir villages.
Statistical analyzes were performed using the SPSS20 software. Pearson correlation coefficient showed a strong correlation coefficient (r = 0.97) between zinc and iron in the soil. This may indicates that the source of these elements is same. A significant positive relationship between sulfur, copper and molybdenum in soil, may indicate their same origin. The concentration of Zinc in the soil has increased with increasing soil also soil organic matter is positively corelated with Zinc(r = 0.86).
The results of principal component analysis showed that different sources fore elements can be divided into two categories :
First category: Copper, molybdenum and sulfur: these elements most likely originated from industrial activities and are slightly geogenic. It seems that the concentrations of these elements is because of the region's oil-rich and oil extraction activities. In the Golgir village high sulfur in the soil is probably due to the activity of Karoon Cement factory.
Second category: iron, zinc and molybdenum are in this category. Because the concentration of these elements is in the normal range they have probably geogenic origin.
 

Contamination of soils by heavy metals is a serious environmental problem and threats human health.This study was performed to assess soil quality, and identify heavy metals in surface soils in Bandar Mahshahr and Bandar Imam, Khuzestan province which have been influenced by human activities. 30 topsoil samples (0-5 cm) were collected from study areas and considering the prevailing wind direction. Concentrations of heavy metals (Pb, Cu, Ni, Zn, Cr, Cd and As) were determined using ICP-OES. Also Soil properties (OM, pH and EC) were measured. To assess contamination level of the heavy metals, Enrichment Factor (EF), Pollution Index (PI) for each metal and Integrated Pollution Index (IPI) were calculated. Also, potential ecological risk index (RI) originally was calculated to assess the degree of heavy metal pollution in soil. Statistical analysis (principal component analysis, cluster analysis and person correlation analysis) were performed to identify relationships between metals and possible sources.
The mean concentrations of As, Cd, Cr, Ni, Pb, Zn and Cu in the urban soils of Bandar Mahshahr are 4.66, 0.36, 114.20, 60.30, 23.75, 65.50 and 34.45 ppm, respectively. The respective levels in surface soils of Bandar Imam were 6.77, 0.43, 127.4, 55.50, 33.60, 100.40, and 39.30 ppm. In comparsion with upper crust values, the concentration of As, Cr, Pb, and Zn is higher. The decreasing trend of Pollution Index is Cd > As > Pb> Cr > Zn > Ni > Cu in Bandar Mahshahr and As > Cd > Pb > Zn > Cr > Cu > Ni in Bandar Imam. Moreover, the result of Integrated Pollution Index indicated that the stations close to the bus terminal (S9) and oil Refining & Distribution industry (S19) in Bandar Mahshahr, and stations (S21, S23, S24, S5 and S30) in Bandar Imam show the highest level of contamination. In general, heavy metals are moderately enriched except As, Pb, and Cd which highly enriched. The highest RI values were found in samples no. 23 and 24 which were taken of petrochemical complexes in Bandar Imam. Other samples (with RI values greater than 100) were classified in considerable ecological risk group.
Correlation coefficient analysis, principal component analysis (PCA) and cluster analysis (CA) were performed for soil samples of Bandar Mahshahr and three main sources were identified: (1) Cd, Pb, Cr, Ni and As have traffic and industrial sources; (2) Cu and Zn are mainly derived from Municipal and industrial sewages, combined with traffic sources; (3) Mn and Fe originate mainly from natural sources. The results of these analysis for Bandar Imam soil samples show Cd and As have industrial sources; Pb, Cu and Zn are mainly derived from traffic sources, combined with industrial sources; Cr and Mn originate mainly from industrial sources, while Fe have a natural sources.
Bandar Imam is more or less is an industrial center, while Bandar Mahshahr is an industrial-residential city. Mean heavy metals concentrations in surface soils of Bandar Imam were remarkably higher compared to those in urban soils of Bandar Mahshahr. In fact, the higher density of industrial activities in Bandar Imam are largely responsible for this subject.
 

Today, with the establishment of industrial units in rural and urban areas and concentrating around the rivers, these ecosystems are highly assailable to the entry of metal contaminants. This study was carried out to determine the concentration ,origin and toxicity of heavy metals (Fe,Mn,As,Ni,Pb,Zn,Cu,Cr) in surface sediments of Bahmanshir River.14 surface sediment samples (0-10 cm) were collected using a grab sampler. Concentration of heavy metals were measured using ICP-OES. Physico-chemical parameters (pH,OM,Clay) of sediment were determined by standard methods. The results of the concentration of heavy metals in the sediment were compared with quality standards.
In order to assess sediment contamination to heavy metals, Enrichment Factor , Contamination Factor and Pollution Load index were calculated; In order to assess toxicity, Ecological risk and Potential accute toxicity were also calculated. The results showed moderate contamination of sediment with metals nickel, chromium؛and low risk level of sediments; moderate Enrichment Factor for some stations; and toxicity of some stations to metals, lead, zinc, copper, nickel and chromium. The Statistical analysis showed that metals Pb,Zn,Cu,Cr may have originated from anthropogenic sources; As can originate from natural sources and Ni seems to have both natural and anthropogenic sources.
 

Heavy metals are the most important contaminants in the environment. Contamination of soil and crops with heavy metals is a growing problem in industrial areas. Login toxic metals through human activities resulted in soils and the plants pollution. The use of waste water for irrigation, fertilizers, pesticides and industrial wastes as well as releasing wastes in the fields has been caused agricultural contamination. The purpose of this study is determining the concentration of heavy metals (Pb, Zn, Ni, Cr, Cu, Cd, Mn) in wheat farms of Ahvaz. For this purpose, 5 wheat farms were selected. 5 composite soil samples (0-30 cm ) and a composite wheat sample from each farm were taken and total of 25 soil samples and 5 wheat samples were collected. After preparation of the samples in the laboratory, the concentration of heavy metals in soil and wheat samples, were measured using ICP-OES and ICP-MS method. The degree of soil pollution was evaluated using contamination and enrichment factor, degree of contamination and Pollution load Index. Statistical analysis was carried out using SPSS 16 software. The results showed that the concentration of chromium in all stations is higher than all applied standards (Europe Union( Eu), the World Health Organization (WHO), the upper continental crust and USEPA ). The average concentration of nickel in the soil was higher than all applied standards. the concentration of elements in the wheat samples was below the FAO-WHO standard and maximum tolerance of heavy metals.

 

In this study, the distribution of heavy metals (As, Cr, Ni, V, Mn, Fe, Zn, Pb) and sulfur in the soil samples around the petrochemical complex and petroleum refinery of Abadan has been investigated. According to the subject of this research, we attempt to investigate the concentration of heavy metals. However, due to the high concentration of sulfur and its environmental importance, this element being surveyed too.
For this purpose, 22 surface soil samples were collected considering the prevailing wind direction (NW-SE). Sample number 22 is control sample that collected from a rural area. After preparation in the laboratory, the samples were analyzed using ICP-OES method to assess concentrations of elements. Also, pH and organic matter content of samples were measured by standard methods. Pollution level of soil samples were investigated using different indices including pollution index, integrated pollution index, enrichment factor, anthropogenic enrichment percent, potential ecological risk index, saturation degree of metals and Potential acute toxicity. The mean concentrations of elements in the samples were compared to mean concentration of these metals in the upper crust and worldwide soil, and EPA standards. The results of calculation geochemical indices indicated that soil samples are more contaminated to S, Pb and Zn. The statistical analysis showed that V, Fe and Mn may be mainly derived from geogenic sources. Lead and zinc may originated from traffic and vehicle emissions and petrochemical complex and petroleum refinery activities. As, Ni and Cr have both geogenic and anthropogenic origin. High concentrations of sulfur in study area originated from petrochemical complex and petroleum refinery activities.
 

Water pollution in the developing countries is caused by urban, industrial and agricultural sources and a general lack of pollution prevention laws and their enforcement. Bahmanshir River is located in Khuzestan province in southwestern of Iran is a branch of Karoon River and plays an important role as a drinking, agricultural and industrial water supply. The purpose of this study was to assess the influence of Abadan city on the surface water quality of Bahmanshir River. On April 2015 (dry season) thirteen surface water samples were collected from Bahmanshir River for determining of major elements (Ca, Na, Mg, K), heavy metals (Al, Fe, Mo, Cu, Ni, Cd, V), and nutrients (total nitrate and total phosphate) concentrations. In general concentration of most heavy metals measured in water samples were very low or below detection limit. The average concentrations of heavy metals in surface water are reduced as follows: Cd <V <Cu <Ni <Mo <Fe <Al. Compared with the global average concentrations of heavy metals which are carried in solution in non-contaminated rivers, the values of these elements in Bahmanshir river are slightly higher, that might suggest the influence of Abadan city on the water of river. The results showed that the concentration of the most metals not exceed the recommended standard World Health Organization (WHO) for drinking water. Only Al concentration at the station S4 (0.25 mg/l) and Cd concentration at the station S9 (0.0051 mg/l) were a little more than the standard recommended by the World Health Organization for drinking water which are 0.2 mg/l for AL and 0.003 mg/l for Cd. The mean concentrations of major elements (Na 407.2 mg/l; Ca 175.4 mg/l; Mg 62.9 mg/l and K 5.3 mg/l) were higher than the global average values (3.7 mg/l for Na; 8 mg/l for Ca; 2.4 mg/l for Mg and 1 mg/l for K). The mean concentrations of major elements are reduced as follows: K <Mg <Ca <Na. High concentration of the major elements in the river can be attributed to the geographical place this river in dry region, high evaporation rate, intrusion of Persian Gulf’s water during high tide and the entrance of dissolved substances from formation geological, in upstream. Pearson correlation and Principal component analysis (PCA) were used to determine the correlation between elements and physicochemical parameters to identify possible sources of elements. The results revealed that both natural and anthropogenic sources affect the quality of surface water of Bahmanshir River. The results for nutrients (nitrate and phosphate) showed that point sources such as urban wastewater and effluent from pond fish play important role in river pollution. However, date palms on both sides of the river can be considered as potential pollution sources in the wet season. The results of the metal index based on guideline values that recommended by World Health Organization (2011), Standards and Industrial Research of Iran for drinking water and recommended max concentration by FAO (1985) for irrigation usage, showed that the most sites were slightly affected by heavy metals. Human health risk due to metals was assessed using the health quotient (HQ). The results showed that the HQ for each of the metals and all metals was less than one and is in the safe and satisfactory range, showing that river water usage for drinking can’t threat health of local people. According to the result of Wilcox chart, all stations (except for S11 , which plotted placed in category (C4S3) and is too salty and harmful for irrigation) are plotted in the category C4S2 which are unsuitable for agriculture .The regional climatic conditions such as low rainfall, high temperature, intensity of evaporation and intrusion of Persian Gulf’s water during high tide have influenced the quality of river water

This study examines the Karun River sediments with heavy metals. For this purpose, 24 samples of surface sediments (0-5cm), and a core samples were collected. Concentrations of heavy metals Chromium,Copper,Zinc,Lead,Arsenic,Nickel,Manganese and Iron were determined by ICP-MS method in ACME labroter in Canada. Also in order to assess the environmental factors on the distribution of metals, physicochemical parameters(pH,OC) were measured. Following sampling and analysis of the samples, in order to assessment of the pollution degree, different indices including sediment quality guidelines (SQGs), (SQG-Q), modified degree of contamination(mCd), the saturation degree of metals (SDM), the risk index ecological potential (RI), the percentage of anthropogenic factors, potential acute toxicity sediment toxicity degree (STd), toxity load index (TLI), the pollution load index (PLI), were calculated. The deep sample of the core was used as the local background. The concentration of heavy metals in core sample, showed that the cocentration decreases with depth. Based on sediment quality guidelines (SQGs) most adverse biological effects can caused by nickel and chromium. Toxicity load index showed that the toxicity of the region is relatively low. Potential acute toxicity (Σ TU), is mainly due to nickel and chromium; Lead has the lowest role in toxicity. The modified contamination degree (mCd), describes zero to moderate level of pollution in the region. Saturation degree of metals (SDM) showes the availability of most metals at stations 4, 16 and 23. Potential ecological risk index indicates that the level of risk is low in the sediment. Anthropogenic percent index, shows the highest percentage for copper, lead and zinc at stations 16 and 19. Statistical analysis indicates the high correlation between OC, copper, lead and zinc. Also the correlation of iron, manganese, chromium, nickel and arsenic, can show the same origin for there metals. pH shows negetive correlation with Lead, Zinc and Copper, and reflects that the mobility of these metals decrease with pH. Principal component analysis represents two major factors. The first factor consisted of nickel, arsenic, chromium, iron and manganese, and the second consisting of copper, lead, zinc and OC. The same results obtained by cluster analysis. STd and SQG-Q indices represent the medium to low toxicity for most of the stations and Toxicity Load Index (TLI) indicates the low toxicity for the region.

As the matter of fact soil is a shelter for earth creatures specially human being, it is also a unique environment for animals and specially plants. Generally, all measured heavy metals concentrations and significant trace elements for iron–steel industry (Zn, Pb, and Cu) were relatively higher than those which were previously reported in rural and urban soils globally. Khuzestan steel company is cated in the southwest of Ahvaz city. In order to assess the impact of this company on soil pollution, total of 17 composite soil samples (0-10 cm)(12 soil samples from around steel company and other 5 soil samples of the soils affected by steel industry effluents) were taken at various distances and considering the prevailing wind direction. After preparation in the laboratory, the samples were analyzed using ICP - OES method to determine concentrations of heavy metals (Cr, Fe, Mn, Ni, Pb, Zn and Cd). Also physicochemical properties of soils (pH, OM and size distribution) were measured.
In order to assess the heavy metal pollution, different indices including Enrichment Factor(EF), Pollution Index(PI), Integrated Nemerow Pollution Index(IPI), Anthropogenic Enrichment Percent(%An), and Saturation Degree of Metals were used. Also statistical analyses including principal component analysis and Cluster Analysis were used to identify the origin of the metals. The average concentration of heavy metals in soil samples were compared to mean unpolluted world soil, mean concentration in upper crust, and local background.
The results showed that, the soil samples compare with the standards an more polluted. Also soil samples affected by the effluent compared to unpolluted soils are more polluted.

 

Highest enrichment factor (EF) obtained for iron (10.3) and the lowest for chromium (0.96). Also for soil samples affected by the effluents, cadmium and zinc are not enriched, while, manganese, nickel, lead, iron and chromium with low enrichment.
Results of pollution index indicated that the stations close to the factory and in the downstream wind direction, and downstream of the effluent discharge show the highest levels of contamination (stations 4, 12, 14 and 17). Moreover the results of Integrated Nemerow Pollution Index showed that soils around factory are more contaminated to Iron and Lead and soil samples affected by effluent to Iron.
The results of Anthropogenic enrichment percent, indicated that in soil samples around the factory, metals Lead, Iron, Chromium, Cadmium and Manganese have an anthropogenic source, and the source of zinc and nickel is mainly geogenic.
In soil samples affected by the effluent, Iron, Manganese, Lead have anthropogenic source, Nickel, both anthropogenic and geogenic sources, and Cadmium, Zinc and Chromium are of geogenic source.
In the soil samples around the factory the highest saturation degree of metals is related to the stations 4, 12, and in the soil samples affected by effluent is related to stations 14 and 17.

Pearson correlation coefficients showed that, Nickel, Iron, Lead, Zinc, and Manganese, are highly correlated also Cadmium and Organic Matter are negatively correlated.
principal component analysis obtained 3 main components also cluster analysis (CA) obtained 2 main clusters (Pb, Zn, Mn, Cd whith anthropogenic source) and (Ni, Fe, Cr both anthropogenic and geogenic sources).
 

Since heavy metals are persistent pollutants and can accumulation sediment so the cancentrations can shows the pollution of aqueous ecosystem. Purpose of this study is assessment of heavy metal contamination in the sediments of Khorramabad river. For this purpose, 17 surface sediment samples were collected along the river . The concentration of heavy metals (Cr, Ni , Pb, Zn , Cu , Mo and As) and physicochemical properties of sediments (clay content , pH, organic matter) were determined.To assess the contamination of sediments, the contamination factor (CF), the Igeo pollution load index (PLI), potential ecological risk index (RI), and potential ecological risk factor (Ei) were measured. Also, statistical analysis were carried out to determine the probable source of heavy metals in the sediments.The results showed that the concentrations of Pb, Zn , Cu and Ni in some of the stations were higher than the average shale and local background. The concentration of Cr in all stationas was above the concentration of this metal in average shale. The concentration of chromium in some stations were below the concentration of this metal in local backgrand. More overy the concentration of Mo and As in all of the stations were below the average shale and in some of the stations were higher than the local backgrand. Pollution Load index revealed that the some stations are polluted. Calculation of contamination factor also indicated that sediment are polluted with Ni, Cu, Pb and Zn at most of the stations, and Cr at all of stations (exept 2 stations). Contamination factor level for Mo was below 1 for more stations. Potential ecological risk index and potential ecological risk factor classified sediments in classe 1 (low pollution). Statistical analysis indicated anthropogenic sources of pollution in the sediments of Khorramabad river.