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In northern Chile, economic activities related to mining and thermoelectric energy have existed in the city of Tocopilla since the early 1900s and metal concentrations in soils have likely been altered by historic anthropogenic activities. To assess the concentrations of Cu, Zn, Pb, Ni, Co, and Cr in urban soils of Tocopilla, a total of 70 superficial (2 cm) and 70 deep (20 cm) soil samples were collected in 2014. Furthermore, to analyze concentration changes in soils over time, 18 superficial (5 cm) samples were collected in 2020–2021. A numerical evaluation (geoaccumulation index, and enrichment factor), principal component analysis, and spatial distribution approach were applied to infer geogenic and anthropogenic influence on the concentrations of these elements. The main conclusions of this research indicate that urban soils of Tocopilla contain geogenic Cu, Zn, Pb, Ni, Co and Cr. However, elevated concentrations of Cu, Zn, and Pb cannot be attributed to a geogenic origin alone, as a proportion of their enrichment is considered to be anthropogenically sourced. The contamination of anthropogenic elements has been found to be related to historic copper mining and thermoelectric energy production. Furthermore, when compared to other sites globally, median concentrations of Cu (945 mg/kg in 2014 and 823 mg/kg in 2020) and Zn (305 mg/kg in 2014 and 196 mg/kg in 2020) in superficial urban soils are among the highest worldwide. Regarding 2020–2021 sampling, Zn and Pb concentrations have increased, while Cu, Cr, Co, and Ni have remained similar to the 2014 samples. [ABSTRACT FROM AUTHOR]

This paper examined the efficiency of artificial neural network (ANN) and multivariate linear regression (MLR) models in the prediction of groundwater quality parameters such as ecological risk index (ERI), pollution load index (PLI), metal pollution index (MPI), Nemerow pollution index (NPI), and geoaccumulation index (Igeo). 40 groundwater samples were collected systematically and analyzed for mainly heavy metals. Results revealed that adopting measured parameters is effective in modeling the parameters with high level of accuracy. Contamination factor results reveal that Ni, Zn, Pb, Cd, and Cu have relatively low values < 1 within the region while the Iron values ranged from low contamination to very high contamination (> 6). PLI, MPI, and ERI results indicated low pollution. NPI results indicated that the majority of the samples were heavily polluted. Quantification of Contamination results revealed that most of the sample's quality was geogenically influenced. Igeo results revealed that most of the samples had extreme pollution. The health risk assessment results revealed that children are substantially prone to more health risk more than adults. The ANN and MLR models showed a high effective tendency in the prediction of ERI, PLI, MPI, NPI and Igeo. Principal component analysis results showed appreciable variable loadings while the correlation matrix results reveal that there exists weak and positive correlation amongst elements. Based on the outcome of this study, this research recommends the use of ANN and MLR models in the prediction of groundwater quality parameters as they yielded positive, reliable, acceptable, and appropriate accuracy performances. [ABSTRACT FROM AUTHOR]

Poultry litter and its biochar has been used recently as alternative effective soil organic amendments due to their significant effect of improving soil properties. However, detailed information on this organic amendment's contribution to the bioavailability of heavy metals in the soil is still lacking. Hence, this study was designed to evaluate the effects of incorporated poultry litter and its biochar on bioavailable Zn, Pb, and Cd concentrations in the soil using various assessment contamination methods. The soil samples treated with poultry litter and its biochar at different application rates of 0, 15, 30, 60, 120 g/kg were collected from a greenhouse pot experiment. The study results indicate a decreasing order in concentrations as follows; Zn (2.04 mg/kg) > Pb (0.22 mg/kg) > Cd (0.02 mg/kg). Geoaccumulation Index (Igeo) for Zn was moderate (0 < Igeo < 1) to heavy contamination (Igeo = 1.00), while Pb Igeo values were within the moderate contamination (0 < Igeo < 1) in all treated soils. Furthermore, Zn and Pb yielded contamination factor (CF) values within the ranges of low contamination (CF < 1) to moderate contamination (1 < CF < 3), nonetheless Zn exhibited the highest CF compared to Pb and Cd. Higher values of Pollution Load Index (PLI > 1) were observed, indicating the pollution level. Those PLI values point out the need to evaluate bioavailable heavy metals levels rather than total metal concentration for risk assessment of soil contamination by organic amendments. [ABSTRACT FROM AUTHOR]

Assessment of spatial variations in the concentrations of potentially toxic metal Pb, Zn, Cu, Cr and Fe was carried out along three roads in Sfax region to identify possible changes in their levels. Concentrations were determined using atomic absorption spectrometer. The study found that for the samples collected along Gremda road the mean concentrations of Pb, Zn, Cr, Cu and Fe were from 2.5 to 110.3; 21.3 to 255.8; 0.8 to 13.7; 0.9 to 11.8 and 9190.8 to 17,267.7 µg/g, respectively. For the samples collected along Manzel Chaker road, obtained concentrations of Pb, Zn, Cr, Cu and Fe ranged between 1.6 and 36.2; 9.8 and 79.2; 2.1 and 7.1; 1.3 and 15.9; 3065.6 and 4084.4 µg g1− for Pb, Zn, Cu, Cr and Fe, respectively. For the sample of Tunis, they ranged between 6.8 and 60.2; 1.6 and 119.6; 1.2 and 6.7; 0.9 and 3.4 and 13,691.7 and 18,091.7 µg g1− for Pb, Zn, Cu, Cr and Fe, respectively. The use of different pollution indexes: geoaccumulation index (Igeo), contamination factor (CF), pollution load index (PLI) and enrichment factor (EF) showed the anthropogenic sources of Pb, Zn, Cu and Cr and the natural sources of Fe. The study indicated that the soils on the Gremda road are highly contaminated with Zn and Pb and no contamination with Cu and Cr. The other two roads showed lower contamination with Pb and Zn and no contamination with Cu and Cr. This difference is related to the variation in exposure to road emissions, the road activity and to the effect of climatic factors. [ABSTRACT FROM AUTHOR]

In the present study, an attempt was made to characterise bed sediments with respect to a river system, wherein sediment samples collected from May 2018 to June 2019 were subjected to bulk digestion and chemical partitioning. The concentrations of metals (Mn, Cu, Zn, Fe, Pb, Co, Cd) bound to five sedimentary phases or fractions were estimated using atomic absorption spectroscopy. On the basis of the five phases, the anthropogenic portion was estimated and are as follows: Mn (63%) > Zn (50%) > Cu (49%) > Cd (46%) > Fe (45%) > Pb (36%) > Co (34%). Then, anthropogenic contamination, as well as the ecological risk, was calculated using pollution load index (PLI), geoaccumulation index (Igeo), enrichment factor (EF), pollution index (IPOLL), potential risk of individual metal (Er) and potential ecological risk (PERI). Igeo and PLI show a continuous anthropogenic impact on the sediments in the post-monsoon months. IPOLL shows Mn falls in the 'Moderately contaminate' category, Cu and Zn falls in the 'Uncontaminated to moderately contaminate' category and rest falls in the 'uncontaminated category'. From EF, Zn (7.98), Cd (6.40) and Pb (5.08) are significantly enriched in the river sediments indicating the source of metal as anthropogenic in origin. Er value of Cd in September is greater than 80, indicating 'considerable ecological risk'. PERI value has the maximum for Cd (126.92), which belongs to the category 'Low ecological risk'. Even though PERI indicates 'low ecological risk' to the sediment contamination, continuous monitoring and management are needed in rivers to avoid significant pollution from domestic, commercial activities, agriculture and industrial activities as EF values are high for Zn, Cd, and Pb, which shows anthropogenic contamination. [ABSTRACT FROM AUTHOR]

We collected water samples from contaminated Buddha Nullah drain in Ludhiana district of Punjab (India) during pre- and post-monsoon seasons of the year 2017 and 2018. The soil and plant (wheat and rice) samples were also taken from fields cultivated near the water sampling sites. The drain is mainly contaminated by discharge of industrial and urban effluents from the surrounding areas and its confluence with Sutlej River (a tributary of the Indus River). Water samples were analysed for nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn). Soil, rice and wheat grain samples were analysed for total metals. Besides this, soil samples were also analysed for and DTPA-extractable metals. The concentration of Cr, Pb and Fe in water exceeded the WHO guidelines during all the seasons. Total Zn, Pb, Mn, Ni and Co concentration in soils exceeded the permissible limits, whereas the average concentration of Fe, Pb, Co and Cd in rice and wheat grains exceeded the permissible limits. The bioaccumulation factor (BAF) for DTPA-extractable heavy metals was in the order: Fe > Cr > Co > Zn > Pb > Cd > Mn > Cu > Ni (BAF values > 1 for all the metals). Heavy metal toxicity load values (HMTL) in water samples were lower than the tolerable toxicity load of heavy metals. However, heavy metal pollution index (HPI) was higher than 100 in all the water samples. Based on the grading of geoaccumulation Index (Igeo), total Cd concentration showed extreme contamination around the soils of Buddha Nullah. The cancer risk associated with heavy metals due to intake of wheat and rice grains and ingestion of soils were in the order: Cd > Ni > Cr. Spatial distribution maps of HPI showed the maximum contamination and health risks were around the areas having higher industrial and urban activities These results suggest that heavy metals particularly Cd cause potential health risks to urban residents and environment. The HPI and HTML for water, Igeo for soils and BAF for plants are useful for assessing heavy metal contamination. The controlling measures must be taken to reduce the heavy metal contamination in the drain by checking of the urban and industrial effluents discharged in it and cleaning of the Buddha Nullah drain should be initiated to improve the water quality of Sutlej River. [ABSTRACT FROM AUTHOR]

Studies related to heavy metal concentrations in coastal sediments are important to monitor and assess environmental health of estuarine ecosystems. Twenty-eight samples from Parnaíba River Delta, the largest open-ocean delta in the Americas, northeastern of Brazil were tested for heavy metals concentrations (Cd, Cr, Cu, Mn, Ni, Pb, Zn, Al and Fe), grain-size and easily oxidizable carbon. The relations of the heavy metals with sediment composition were evaluated using a multivariate statistical analysis. Sediment pollution assessment was carried out by enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF) and potential ecological risk index (PERI). The average concentrations were 0.50 ± 0.09 mg Cd kg−1, 6.95 ± 2.13 mg Pb kg−1, 19.02 ± 8.75 mg Cu kg−1, 23.20 ± 5.04 mg Ni kg−1, 33.52 ± 6.82 mg Cr kg−1, 43.99 ± 7.47 mg Zn kg−1, 165.73 ± 86.71 mg Mn kg−1, 2.93 ± 0.89% to Fe and 3.78 ± 1.17% to Al. The results indicate lower concentrations of heavy metals relative to limit concentrations defined by the Brazilian regulatory framework. The multivariate analysis reflected the binding of heavy metals to clay minerals and organic carbon. The different geochemical indices indicated sediments minimally enriched by metals and a low potential ecological risk level. Our assessment confirms the pristine conditions of Parnaíba Delta protected area to heavy metal contamination, except Igaraçú channel near Parnaíba city. [ABSTRACT FROM AUTHOR]

This study reported the first comprehensive research on identification of metal concentrations (Fe, Mg, Mn, Pb, Cd, Cr) in order to provide baseline data for future studies, identify possible sources, determine degree of pollution, and identify potential ecological risks of metals in surface sediments from Iran's Choghakhor Wetland. The order of metal concentration was as follows: Fe > Mg > Mn > Pb > Cd > Cr, with mean concentrations of 6140.35, 1647.32, 289.03, 1.10, and 0.45 µg/g of dry weight, respectively. These results reveal that Choghakhor Wetland is not heavily polluted compared to other regions. The results of enrichment factor (EF) and geoaccumulation index ( I ) showed that Fe, Pb, Mg, Cr, and Mn presented low levels of contamination and probably originated from natural sources. On the other hand, the results of EF and I indices suggested that Cd concentrations in sediments of Choghakhor Wetland originated from anthropogenic sources. Based on the results of three sets of sediment quality guidelines, only Cd concentration in sediments of Choghakhor Wetland is a threat for aquatic organisms of Choghakhor Wetland. The results of multivariate analysis such as principal component analysis and cluster analysis showed that Fe-Mn, Cr-Mg, and Pb groups originated from natural sources, while Cd concentrations in sediments of Choghakhor Wetland originated from both natural and anthropogenic sources (mainly chemical fertilizers). To our knowledge, this is the first study about metal concentrations in sediments of Choghakhor Wetland, and because of low levels of these metals, these concentrations can be considered background levels for future investigation. [ABSTRACT FROM AUTHOR]

The present study to find seasonal (September 2010-June 2011) heavy metal (Cd, Pb, Cr, Co, Ni, Zn, Cu, Fe, As) contamination and the origins thereof in surface sediments of Gökçekaya Dam Lake, as constructed on Sakarya River, the third-longest river in Turkey and the largest river of the Northwestern Anatolia. Upon analyses for the purpose thereof, heavy metal contamination in annual average concentrations in the lake sediment varied, respectively, as Fe > Zn > Cr > Ni > Cu > Pb > Co > As > Cd. Statistical assessments performed in order to see whether the average values of the heavy metal contamination as measured at stations placed in the lake changed by seasonal periods. There found statistically significant differences especially in Cd, Zn, and Pb between seasonal periods. In accordance with the Sediment Quality Index, Gökçekaya Dam Lake sediment was classified as 'highly polluted' in terms of the amount of anthropogenic contaminants of As, Cr, Cu, Ni, Pb, and Zn. Enrichment factor and geoaccumulation index values ( I ) were calculated in order to geochemically interpret the source of contamination due to heavy metal concentration in the lake sediment and the level of pollution. The As, Co, Cr, Cu, Ni Pb, and Zn values demonstrated that the sediment was rich for anthropogenic contaminants. The lake was found especially rich for arsenic (14.97-34.70 mg/kg) and lead (68.75-98.65 mg/kg) in accordance with annual average values. In general the lake was geochemically characterized as 'moderately contaminated' in terms of As, Co, Cr, Cu, Ni, Pb, and Zn content. [ABSTRACT FROM AUTHOR]

Subarnarekha river, a rain fed peninsular river, passes through the city of Jamshedpur is an important industrial centre of Jharkhand, India. The aim of the study was to investigate the seasonal variability in the water and sediment quality status and to assess the impact of metals contamination in various seasons due to mining and industrial discharge. Concentrations of Zn, Pb, Cr, Cd, Ni, and Cu were determined using ICP-MS. Concentrations of Pb, Ni, and Cd were found quite higher than Indian drinking water standards. Heavy metal concentrations in sediment were found much higher than river water, which was further supported by high contamination factors (Cf > 6) for Cd and Pb for all sites in pre-monsoon whereas, high degree of contamination (Cd > 24) further ensured heavy pollution. Pollution load index values were found >1 which suggest progressive deterioration of sites whereas, geoaccumulation index recommended sediment quality towards moderately to very strongly polluted condition. Principle component analysis (PCA) was conducted separately for pre- and post-monsoon seasons. PCA (with eigen value >1 focused on two components, irrespective of seasonal variation with 55.21–58.77 % variance) indicated that high metals loading are due to anthropogenic origin, and Zn, Pb, Ni, and Cr have significant loading. Coupling of bioremediation technology with other economically efficient methods could help in solving the problem. [ABSTRACT FROM AUTHOR]

The major aim of the present study is to assess (1) depth-wise physico-chemical characteristics and pseudo-total metal concentrations in the abandoned chromite-asbestos mine waste, contaminated agricultural soil, and control agriculture soil; (2) degree of soil contamination and metal geoaccumulation index in agricultural soil; and (3) concentrations of metal in the sediment and water samples of river, tributary, and different water bodies located in the vicinity of an abandoned chromite-asbestos mine of Roro hill. Nutrient content and physical properties of the mine waste were found low and poor. Pseudo-total metal concentrations in the mine waste were found in the order of Cr > Ni > Mn > Cu > Pb > Co > Zn > Cd. High concentrations of Cr (1148 mg kg) and Ni (1120 mg kg) were found in the contaminated agricultural soils which far exceed the soil threshold limits. The contamination factor and geoaccumulation index in the agricultural soils were found high and decreased with increase in depth for Cr and Ni, indicating strong contamination. Concentrations of Zn, Mn, Co, Cu, Pb, and Cd were found low and within toxicity limit. Further, metal grouping and site grouping cluster analysis also revealed that Cr and Ni are closely linked with each other and chromite-asbestos mine waste was the major source of contamination. Sediment samples were found high in metal content and decreased with increase in distance and mine waste influence. Water flowing from the mine adit was found high in Cr and Ni concentration (above critical drinking water total concentration). Further research is required to study the pollution factors for sediment and water samples and metal accumulation pattern in naturally growing plants and locally practised crops to access its impact on human and livestock. [ABSTRACT FROM AUTHOR]

The Doce River Basin (DRB) is located in the southeastern region of Brazil and is home to the largest steel complex in Latin America, including the largest open pit mining industry in the world. Several economic activities are performed along the DRB, including mining, agriculture, and food industry activities. The mining activities involve the exploration of a range of minerals and gold on a smaller scale. The quality of water in the basin has been monitored since 1997 by the state agency for environmental control; however, there are no reports about metals in sediments of the basin. There is insufficient information for an assessment of metal distribution in the DRB, especially for the most toxic metals, such as mercury. Therefore, the aim of this work is to quantify Al, Cr, Co, Cu, Fe, Hg, Mn, Pb, and Zn levels and the physico-chemical parameters in sediment from the basin and to statistically analyze these variables. The results are also discussed using the geoaccumulation index ( I) and enrichment factor (EF), which contribute to the knowledge of the metal geochemistry in this basin. The results for Cr, Cu, Hg, Pb, and Zn indicate that 41 % of the sediment samples analyzed were above the sediment quality guideline value (SQG), and the use of geochemical parameters indicated that eight points of the basin were considered the most contaminated. Therefore, this study revealed that an implementation of a sediment monitoring program is of great value. [ABSTRACT FROM AUTHOR]

Thirty intertidal surface sediment samples with replicates were collected from Port Klang and the concentration of metals, sediment particle size and amount of organic matter were determined. The mean metal concentrations as in descending order were: Mn (136.991 ± 46.800 mg kg) > Zn (48.249 ± 25.790 mg kg) > Cr (24.175 ± 4.739 mg kg) > Pb (15.560 ± 5.475 mg kg) > Ni (6.860 ± 1.693 mg kg) > Cu (6.777 ± 9.064 mg kg) > Co (1.854 ± 0.352 mg kg) > Cd (0.074 ± 0.054 mg kg). The Klang River and the Langat River were identified as the point of entry for metals to the Lumut Strait. Metal accumulations were found to occur near or within the Klang and the Langat River estuary and also along the Lumut Strait. The enrichment factor and the geo-accumulation index revealed enrichment of Cd, Cu, Pb and Zn by anthropogenic sources. In addition, Cu concentration at two stations located near a commercial jetty, marina and shipyard had also exceeded the ISQG level by the Canadian Interim Marine Sediment Quality Guideline. Principal component analysis showed that concentration of Cd, Cu, Pb and Zn was more dependent on Klang River, as compared to Langat River which had more influence on the concentration of Co, Cr, Mn and Ni. It was shown that presence of clay, silt and organic matter favored metal retention in the sediment. [ABSTRACT FROM AUTHOR]

During large constructions of roads or structures, unexpected acid rock drainage (ARD) can be caused by local mineralization containing sulfides in the geology. The potential of ARD occurrence of a certain area sometimes must be assessed before initiation of any engineering earth works. However, it is difficult to assess the entire area through collecting rock samples and predicting the potential by laboratory tests, such as the acid-base accounting method. In this study, a new prediction protocol using a geochemical exploration survey technique of stream sediment is proposed. Sediment samples were collected at the case study area where a large development is expected in the future, and the contents of some major and heavy metal elements were compared according to the major geologies of the sampling points. The modified geoaccumulation indices ( I) of Fe, Pb and As could indicate a possible zone of pyrophyllite mineralization, which may cause the occurrence of ARD at the study area. Using the enrichment index of the three elements relative to the median values of the area, a high potential zone of ARD could be designated, which was in agreement with the laboratory ARD prediction tests of the rock samples. In the other areas with different mineralization processes, other metallic elements can be selected as indicators of the ARD potential. Likewise, the potential of the occurrence of ARD at an area can be assessed by evaluating the geochemical distributions and drawing the indicator elements for ARD through a stream sediment survey. [ABSTRACT FROM AUTHOR]

Heavy metal concentrations were examined in 30 soil samples from Gebeng industrial city, Malaysia using inductively coupled plasma-mass spectrometry for As, Ba, Cd, Co, Cr, Cu, Ni, Pb and Zn, and direct mercury analyzer (DMA-80) for Hg. Multivariate statistical techniques including hierarchical cluster analysis (CA), principal component analysis (PCA), correlation analysis and analysis of variance were used to identify the spatial distribution and potential sources of heavy metals. The mean concentrations of heavy metals in the soil samples are in decreasing order as follows: Co > Ba > Zn > As > Pb > Cr > Cu > Ni > Hg > Cd. The Gebeng soils are characterized by high mean relative concentration of As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in the industrial zone (IZ) than the Kampung-Balok residential area (KB) and submerged area (SA), indicating inputs from industrial activities. Geochemical results suggested that Gebeng soils are primarily polluted by As, Co, Hg, Pb, and Cu subsequently derived from anthropogenic sources. PCA and CA in the heavy metals indicate both anthropogenic and natural origin. However, the geoaccumulation index and pollution load index further confirm the high contamination levels of the heavy metals in IZ and low to uncontaminated in KB and SA regions. [ABSTRACT FROM AUTHOR]

This paper presents a study on the Wular Lake which is the largest fresh water tectonic lake of Kashmir Valley, India. One hundred and ninety-six (196) water samples and hundred (100) sediment samples ( n = 296) have been collected to assess the weathering and Anthropogenic impact on water and sediment chemistry of the lake. The results showed a significant seasonal variability in average concentration of major ions being highest in summer and spring and lower in winter and autumn seasons. The study revealed that lake water is alkaline in nature characterised by medium total dissolved solids and electrical conductivity. The concentration of the major ion towards the lake central showed a decreasing trend from the shore line. The order of major cations and anions was Ca > Mg > Na > K and HCO > SO > Cl, respectively. The geochemical processes suggested that the chemical composition lake water is mostly influenced by the lithology of the basin (carbonates, silicates and sulphates) which had played a significant role in modifying the hydrogeochemical facies in the form of Ca-HCO, Mg-HCO and hybrid type. Chemical index of alteration values of Wular Lake sediments reflect moderate weathering of the catchment area. Compared to upper continental crust and the post-Archean Shale, the sediments have higher Si, Ti, Mg and Ca contents and lower Al, Fe, Na, K, P, Zn, Pb, Ni, Cu content. Geoaccumulation index (Igeo) and US Environmental Protection Agency sediment quality standards indicated that there is no pollution effect of heavy metals (Zn, Mn, Pb, Ni and Co).The study also suggested that Wular Lake is characterised by both natural and anthropogenic influences. [ABSTRACT FROM AUTHOR]

We present multi-element concentrations in the surface sediments from the offshore of Cauvery delta of southeast India to evaluate the impact of coastal pollution on the geochemical behaviour of surface deposits. For this study, 16 surface sediment samples were collected from the offshore of Cauvery delta of southeast India and were analysed using traditional XRF for various major (SiO, AlO, MgO, FeO, MnO, NaO, KO, CaO, PO, TiO) and trace elements (Rb, Sr, Ba, Y, Zr, Nb, V, Cr, Co, Ni, Cu, Zn, Th, Pb) after powdering it to ASTM 230 (<63 μm). The main objectives of this study were to understand the geochemical behaviour of the coastal surface sediments and its performance and relation with the pollution indices and statistical analysis. To meet out the objective, pollution indices such as enrichment factor (EF), contamination factor (CF) and Geoaccumulation Index ( I) were calculated and statistical analyses were performed to understand the relationship between the geochemical parameters. Both EF and I show the enrichment of Cu, Cr and Zr, whereas CF shows enrichment of Cu and Cr. Statistical analyses exhibit poor correlation between these elements and fine fraction indicating the insignificant role played by both grain size and organic matter. Strong positive association between Cu and Zn with CaCO exhibits the role of carbonates in precipitating these metals from the overlying water column possibly related to agricultural pollution. Distribution and association of other elements suggest the influence of mineralogy in geochemical composition of surface sediments. Based on this study, we suggest that environmental indices alone should not be considered for evaluating environmental conditions and a prior geogenic characterisation of the sediments is necessary. [ABSTRACT FROM AUTHOR]

In this study, total heavy metal content of soil and their spatial distribution in Sarıseki-Dörtyol district were analyzed and mapped. Variable distance grids (0.5, 1.0 and 2.0 km) were established, with a total of 102 soil samples collected from two different soil depths (0-5 and 5-20 cm) at intersections of the grids (51 sampling point). Soil samples were analyzed for heavy metals (Cd, Co, Cr, Cu, Pb, Zn, Mn, Fe, and Ni). The most proper variogram models for the contents of all heavy metal were spherical and exponential ones. The ranges of semivariograms were between 1.9 and 31.1 km. According to the calculated geoaccumulation ( I) values, samples from both soil depths were classified as partly to highly polluted with Cd and Ni and partly polluted with Cr and as partly polluted-to-not polluted with Pb and not polluted with Cu, Fe and Mn. Similar results were also obtained when evaluated by the enrichment factor. The contamination levels of the heavy metals were Ni > Cd > Cr > Pb > Zn > Cu > Co > Fe > Mn in decreasing order. The soils in the study area are contaminated predominantly by Cd and Ni, which may give rise to various health hazards or diseases. Cadmium pollution results primarily from industrial activities and, to a lesser extent, from vehicular traffic, whereas Ni contents in the study area result from parent material, phosphorus fertilizer, industries, and vehicles. [ABSTRACT FROM AUTHOR]

Urban soil samples collected from the city of Xuzhou were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) for Pb and Zn. The samples were also investigated for mineralogy using X-ray diffraction, thermal analyses and scanning electron microscopy (SEM). The identified minerals are mainly composed of quartz and calcite as major minerals. Soil samples contained elevated Zn (2,049 ± 5,439 mg/kg) and Pb (115 ± 58 mg/kg). According to the index of geoaccumulation, the soils of the study area are considered to be moderately to strongly contaminated with respect to Zn, moderately contaminated with respect to Pb. The magnetic measurements indicate that the dominant magnetic components are multidomain grains of ferrimagnetic minerals and that superparamagnetic and stable single-domain ferrimagnetic grains and non-ferrimagnetic minerals are present in small magnetic concentrations in this area. The measured metals correlated positively with the determined magnetic parameters ( χ, χARM, SIRM and SOFT). This result suggests that simple, rapid, and non-destructive magnetic measurements could provide useful information about Pb and Zn pollution in Xuzhou urban surface soils. [ABSTRACT FROM AUTHOR]

Concentrations of trace elements such as As, Ba, Co, Cr, Cu, Ni, Pb, Rb, Sr, V, Y, Zn and Zr were studied in soils to understand metal contamination due to agriculture and geogenic activities in Chinnaeru River Basin, Nalgonda District, India. This area is affected by the geogenic fluoride contamination. The contamination of the soils was assessed on the basis of geoaccumulation index, enrichment factor (EF), contamination factor and degree of contamination. Forty-four soil samples were collected from the agricultural field from the study area from top 10-50 cm layer of soil. Soil samples were analyzed for trace elements using X-ray fluorescence spectrometer. Data revealed that soils in the study area are significantly contaminated, showing high level of toxic elements than normal distribution. The ranges of concentration of Ba (370-1,710 mg/kg), Cr (8.7-543 mg/kg), Cu (7.7-96.6 mg/kg), Ni (5.4-168 mg/kg), Rb (29.6-223 mg/kg), Sr (134-438 mg/kg), Zr (141.2-8,232 mg/kg) and Zn (29-478 mg/kg). The concentration of other elements was similar to the levels in the earth's crust or pointed to metal depletion in the soil (EF < 1). The high EFs for some trace elements obtained in soil samples show that there is a considerable heavy metal pollution, which could be due to excessive use of fertilizers and pesticides used for agricultural or may be due to natural geogenic processes in the area. Comparative study has been made with other soil-polluted heavy metal areas and its mobility in soil and groundwater has been discussed. A contamination site poses significant environmental hazards for terrestrial and aquatic ecosystems. They are important sources of pollution and may result in ecotoxicological effects on terrestrial, groundwater and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

During the last two decades, the coastal environment of southeast India has experienced intense developments in industry, urbanization and aquaculture. Moreover, the 2004 mega tsunami has devastated this coast, thus affecting the coastal sediment characteristics. These two phenomena prompted a study to characterize the sediment, to understand the mechanisms influencing the distribution of heavy metals and to create baseline data for future impact assessment. Results showed that the coastal sediment was carpeted with a mosaic of sand and silty sand with a minor amount of clay. Heavy metal values showed maximum variation for Fe and minimum for Cd. Their average values showed the following decreasing trend: Fe > Cu > Zn > Pb > Cr > Ni > Cd. This study shows that the major source of metals at Kalpakkam coast are land-based anthropogenic ones, such as, discharge from industrial waste, agricultural waste, urban, municipal and slum sewage into the Buckingham canal, which in turn discharges into the sea through backwaters, particularly during northeast monsoon period. A clear signature of the role of backwater discharge increasing the concentration of a few metals in the coastal sediments during monsoon period was observed. Assessments of the degree of pollution, concentration factor (CF), geoaccumulation index ( I) and pollution load index (PLI) have been calculated. CF values and I indicated that the coastal sediment is moderately polluted by Cu and Cd. Increase in Cu, Pb and Zn concentration during the monsoon period (October-January) compared to the rest of the year was noticed. Factor analysis and correlation among the heavy metals concluded that Cr, Ni, Cd and Fe are of crustal origin, whereas, Cu, Pb and Zn are from anthropogenic sources. Organic carbon content in the sediment increased during monsoon period, pointing to the role of land runoff and backwater discharge in enhancing its content. The study also elucidates the impact of the recent tsunami in depleting metal content in the coastal sediment as compared to the pre-tsunami period. [ABSTRACT FROM AUTHOR]

The concentration of heavy metals such as Ba, Co, Cr, Cu, Ni, Pb, Rb, Sr, V, Y, Zn, Zr were studied in soils of Balanagar industrial area, Hyderabad to understand heavy metal contamination due to industrialization and urbanization. This area is affected by the industrial activities like steel, petrochemicals, automobiles, refineries, and battery manufacturing generating hazardous wastes. The assessment of the contamination of the soils was based on the geoaccumulation index, enrichment factor (EF), contamination factor, and degree of contamination. Soil samples were collected from Balanagar industrial area from top 10-50 cm layer of soil. The samples were analyzed using X-ray fluorescence spectrometer for heavy metals. The data revealed that the soils in the study area are significantly contaminated, showing high level of toxic elements than normal distribution. The ranges of concentration of Cr (82.2-2,264 mg/kg), Cu (31.3-1,040 mg/kg), Ni (34.3-289.4 mg/kg), Pb (57.5-1,274 mg/kg), Zn (67.5-5819.5 mg/kg), Co (8.6-54.8 mg/kg), and V (66.6-297 mg/kg). The concentration of above-mentioned other elements was similar to the levels in the earth's crust pointed to metal depletion in the soil as the EF was <1. Some heavy metals showed high EF in the soil samples indicating that there is a considerable heavy metal pollution, which could be correlated with the industries in the area. A contamination site poses significant environmental hazards for terrestrial and aquatic ecosystems. They are important sources of pollution and may results in ecotoxicological effects on terrestrial, groundwater and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Copper smelting and toxic emissions in Sarcheshmeh Copper Complex have resulted in soil pollution especially in the vicinity of the smelting plant. Calculated geoaccumulation index, contamination factor ( C), and contamination degree ( C) indicate surface soil enrichment in potentially toxic metals (As, Cu, Pb, Zn, Mo, and Cd). The results also indicate that most contaminated areas are located in the prevailing wind directions (N and NE). However, continuous copper smelting can result in extensive pollution in the study area. This is especially alarming for adjacent townships. Since, the sampled sites are also used as grazing land, the soils are likely to become phytotoxic and provide a potential pathway for the toxic elements to enter the food chain. C based on distance and direction give more reasonable results; that is, the decrease of contamination degree with distance. This is in agreement with I and also statistical analysis, which show a decreasing trend of metal loadings of soil with distance from the smelter. Statistical analysis reaffirms the polluting role of the smelting plant. [ABSTRACT FROM AUTHOR]