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

The aim of this work was to determine the concentrations, distribution, and fate of potentially toxic elements [lead (Pb), zinc (Zn), nickel (Ni), copper (Cu), mercury (Hg), arsenic (As), and cadmium (Cd)] in sediments of a hydropower plant water reservoir located in the Brazilian Cerrado biome (used as system model). The purpose of this study was achieved with an analysis of the level of contamination based on the geoaccumulation index (Igeo) and factor contamination (FC) and comparisons with values established by environmental legislation. The physical–chemical–biological properties of sediment samples, the distribution, and the fate of potentially toxic elements (PTEs) in the basin of the stream studied were also investigated using Pearson's correlation coefficient (r) and principal component analysis (PCA). Cu, Hg, and Cd concentrations in the sediment samples from most of the points analyzed were above level II of the categorization stipulated in environmental legislation, characterizing sediments of poor quality. Moreover, Igeo and FC values indicated potential pollution of the water reservoir sediment by Cd. Concentrations of Cd exceeding 0.34 mg kg−1 surpassed the reference values for water quality established by Conama Resolution No. 454/2012, highlighting the urgent need for ongoing sediment quality monitoring strategies. Hence, the study water reservoir was classified as being moderately to extremely polluted due to the fate of potentially toxic metals in the sediment samples. Frequent monitoring of the sediment quality in watersheds with hydropower plants is indispensable for the assessment of water resources, considering the importance of the water supply and power generation for the population. Moreover, water contaminated by PTEs poses potential risks to river basins, as well as to human and animal health. The results of this work can assist in the investigation of other water reservoirs around the world. [ABSTRACT FROM AUTHOR]

This study investigated the distribution of heavy metals in agricultural soils in the vicinity of three large mining landfills of the Kizhnica mine in the Republic of Kosovo. The mining sector is one of the most important sectors of Kosovo's economic development, and the Kizhnica mine is one of the most important ore producers in Kosovo. Besides the positive aspects, the development of production also has some negative side effects, such as the generation of industrial waste and the possible contamination of surrounding areas, including agricultural land. Therefore, ten sampling sites were selected in the vicinity of the Kizhnica mine. These sites were characterized and assessed as the most important due to the anthropogenic impact of mineral processing and open-tailing waste deposits in Kizhnica. The concentration of Pb, Zn, Cu, As, Cd, Ni, Mn and Sb in the selected samples was determined using inductively coupled plasma–optical emission spectrometry. The data obtained were used to create geochemical maps and calculate the contamination factor, pollution load index and geoaccumulation index. Cluster analysis, Pearson correlation coefficient and air spatial distribution patterns using the air dispersion model were used to evaluate within the area. The results showed that heavy metal levels are influenced by the anthropogenic nature of pollution, confirming a current ecological threat from mining activities in the region. In order to improve waste management, reduce the hazardous impacts of mining and contribute to the sustainable development of the region, the potential reuse of the deposited waste material in the construction industry is proposed. [ABSTRACT FROM AUTHOR]

The rupture of an iron mining tailing dam in Brumadinho, Brazil, released around 10 million cubic meters of tailings, of which 1.6 Mm3 reached the Paraopeba River. In this work, a total of 30 samples from three bottom sediment cores were collected in the lower course of the Paraopeba River basin and analyzed for major, trace and rare earth elements by ICP-OES and ICP-MS. The sediments presented a range of compositions with different weathering histories, overall marked by depleted Ca2+, Na+ and K+ compared with the average UCC, PAAS and NASC and some advanced weathering trends. The samples presented a fractionation pattern characterized by a continuous depletion of light REEs from La to Sm and a regular decreased distribution of heavy REEs from Gd to Yb, and the Co/Th vs. La/Sc diagram indicates a predominant intermediate source. The upper samples presented the highest contents of REEs, probably due to the higher presence of iron and aluminum oxides and hydroxides, which can be related to more advanced weathering. The Al, Cu, Ni, V, Zn, Co, Mn, Ti, Fe and Si concentrations and the CF, EF and Igeo index values varied across the sediment core samples, demonstrating that there were long periods of geogenic or anthropogenic contributions. [ABSTRACT FROM AUTHOR]

Potentially toxic element (PTE) contamination of soils and their sources remains one of key global environmental concerns. Agricultural soil in Kalinovac, Podravina region, Croatia is the subject of this study. The main aims include determining the concentration and distribution of PTEs in the soil, differentiation between possible geogenic and anthropogenic sources, and determining the correlation between the analysed PTEs and soil parameters. To achieve these objectives, geochemical analyses of the soil in the study area were carried out. Spatial distribution of the individual PTE contents, enrichment factors (EF), contamination factors (CF), and geoaccumulation index (Igeo) were created using GIS tools. In addition, statistical data processing was carried out, including the calculation of the correlation matrix, hierarchical cluster analysis (HCA), and factor analysis. The obtained results show that certain elements such as lead, chromium, copper, and cadmium were predominantly of anthropogenic origin in the study area, while others tended to have more geogenic origin. By applying different methods used in this study, it is possible to distinguish between geogenic and anthropogenic sources of PTEs in soils of this type. [ABSTRACT FROM AUTHOR]

The present study focuses on the assessment of Hg distribution in both soil and water samples from the small-scale gold mining region of Karang Jaya Sub-district, Musi Rawas Utara Regency, South Sumatra Province. For over 30 years, this region has witnessed persistent utilization of mercury as an amalgam for gold extraction. The investigation encompasses an analysis of total mercury levels in soil samples obtained from Sukamenang, Muara Batang Empu, and Terusan Villages. As a comparative reference point devoid of gold mining activities, the neighboring Muara Lakitan Village was selected. The obtained results indicate a moderate to strong contamination level across the 30 sampled locations based on the Geoaccumulation Index (Igeo), with an average Igeo value of 2.6. Furthermore, Pollution Load Index (PLI) and Contamination Factor (CF) values demonstrate high contamination. Conversely, analysis of river water samples from 30 stations along the Rupit River reveals that most of the samples comply with quality standards (<0.0005 mg/L), with an average value at 0.000322 mg/L; only four stations exhibit total Hg concentrations surpassing regulatory thresholds. All soil and river water samples from the control area (10 stations) exhibited no signs of pollution. Appropriate investments in technology, finance, and technical skills are needed to reduce mercury pollution due to small-scale gold mining activities. [ABSTRACT FROM AUTHOR]

The level of atmospheric heavy metal deposition in University of Lagos, Akoka campus was investigated using the moss Dicranum scorparium Hedw. Moss samples were collected from unplastered perimeter walls and rock surfaces at ten sampling sites labeled AJ: UBA Park (A), Ransome Kuti (B). Makama Hall (C), Faculty of Law (D), Moremi Car Park (E), Medical Centre (F), Ozoluwa BQs (G), High Rise Buildings (H), Honors Hall (I), Lagoon Front (J). A control sampling was done at First Estate, Amuwo-Odofin LGA. The concentrations of Cadmium (Cd), Lead (Pb), Nickel (Ni), Copper (Cu) and Zinc (Zn) were determined using Atomic Absorption Spectrophotometer (AAS) Perkin Elmer AA 800. The results obtained confirmed the presence of heavy metal in this order Zn > Pb > Cd > Cu > Ni. The concentration of Zn, Cd and Pb were greater than the FME and UNEP threshold limiting values. The analysis of the anthropogenic influence of the pollutants on the environment revealed that Zn (4.24mg/L) despite its highest abundance is a moderate contaminant in the study locations. Contamination factor (CF) suggests that locations B, D, F, G and J are seriously contaminated (C5) while locations A, C, E, H, and I are extremely contaminated (C6). The index of geo-accumulation revealed that all the studied locations are in the Igeo7 category indicating extremely pollution with the assayed metals. The difference in the occurrence of anthropogenic activities was seen to be the major factor responsible for the variations in the concentration of heavy metals accumulated by the mosses. [ABSTRACT FROM AUTHOR]

This study examined the spatio-temporality of heavy metal concentrations (Al, Cd, Co, Cr, Fe, Mn, Ni, Pb and Zn) in the sediments of Lake Bafa, one of the most important wetlands of Turkey's Aegean region. The study evaluated sediment quality according to threshold effect concentration (TEC) and probable effect concentration (PEC) values based on sediment quality guidelines (SQG), and provided a potential ecological risk assessment (PERI) along with indices such as geoaccumulation index (NIgeo), enrichment factor (EF), contamination factor (CF), and pollution load index (PLI). For this purpose, surface sediment from 10 different points and core samples from three different points were seasonally collected and the concentrations of nine heavy metals were determined by ICP-MS. The findings indicated the following accumulation order of heavy metals in the sediment: Fe > Al > Mn > Ni > Cr > Zn > Pb > Co > Cd, with concentrations of Al, Mn, and Ni being high in the surface sediment samples. According to the NIgeo, surface sediment and core samples were very slightly polluted with Cr, Mn, and Co at most stations, while five stations were slightly polluted with Cd. Regarding EF, the lake was at risk in terms of Al and Pb accumulation. The CF results indicated that the lake was under pressure in terms of heavy metal pollution. The PLI results indicated a significant pollution hazard at all stations, while the PERI analysis indicated moderate risk of heavy metal pollution at some stations. As one of the most comprehensive studies applying such indices to Lake Bafa, the results are very significant in terms of evaluating the lake's ecological sustainability. [ABSTRACT FROM AUTHOR]

Potentially toxic element (PTE) contamination of soils and their sources remains one of key global environmental concerns. Agricultural soil in Kalinovac, Podravina region, Croatia is the subject of this study. The main aims include determining the concentration and distribution of PTEs in the soil, differentiation between possible geogenic and anthropogenic sources, and determining the correlation between the analysed PTEs and soil parameters. To achieve these objectives, geochemical analyses of the soil in the study area were carried out. Spatial distribution of the individual PTE contents, enrichment factors (EF), contamination factors (CF), and geoaccumulation index (Igeo) were created using GIS tools. In addition, statistical data processing was carried out, including the calculation of the correlation matrix, hierarchical cluster analysis (HCA), and factor analysis. The obtained results show that certain elements such as lead, chromium, copper, and cadmium were predominantly of anthropogenic origin in the study area, while others tended to have more geogenic origin. By applying different methods used in this study, it is possible to distinguish between geogenic and anthropogenic sources of PTEs in soils of this type.

Kufa, considered one of the important cities in Iraq, is facing a rapid increase in population proportion and urban development in buildings and industry. Therefore, the concentration of several hazardous heavy metals is the main focus of this study. It presents the distribution and Estimation of heavy metals in urban lands in the Kufa area as an environmental geochemical study. Twenty samples of urban surface soils were collected in many sites to determine concentrations, distribution, and contamination of elements Cu, Zn, Co, Ni, Th, U, Pb, Hf, Nb, and Fe. The mean concentrations of heavy metals were compared with the local studies, UCC guidelines, and the world reference. To distinguish anthropogenic pollution, EF and Igeo guides were calculated. The obtained results established that contamination in Kufa soil land was slightly polluted by U (2.83ppm) and Nb (10.81ppm) and moderately polluted by Pb (31.7ppm) and Hf (9.75ppm). The research revealed that the reason for the elevation in the lead in the Kufa soil is that it often suffers from severe vehicle overcrowding during religious occasions. [ABSTRACT FROM AUTHOR]

This work is aimed to assess potential risk associated with the presence of metals and metalloids in soil at "Playa Las Petroleras" sector, located in Antofagasta (Chile). The zone under study has been affected by four oil spill events. This sector is located in an urban area by the sea. So, it has a great social and environmental relevance. The concentrations of 15 elements in soil samples were assessed, four of them presenting potential ecological risk: As, Co, Cu, and Pb. Nine pollution indices were applied to data: four single pollution indices and five integrated pollution indices to assess soil pollution. The single pollution indices show that the site bears potential ecological and environmental risk due to the presence of Cu, the site being classified as highly contaminated owing to a severe enrichment of this metal. For Co, all the indices allow classifying the site as little or uncontaminated, while the level of As and Pb pollution could be considered as ranging from uncontaminated to moderately contaminated. The integrated pollution indices show that average concentrations are highly contaminated mainly owing to the presence of Cu. [ABSTRACT FROM AUTHOR]

During the Spanish colonial era, ships frequently transported mercury across the Atlantic to the New World to be used in gold mining. As many of those eventually sank, shipwrecks may represent a local source of mercury contamination in the marine environment. In this context, evaluating mercury contamination in coastal sediments and mercury magnification in marine food webs is crucial for understanding mercury dynamics and estimating exposure to marine life in locations where shipwrecks occurred. This study investigated mercury concentration present in coastal sediments and biota from three distinct groups: macroalgae (Asparagopsis armata and Ulva lactuca), gastropods (Littorina striata and Patella candei gomesii) and crustaceans (Palaemon elegans and Pachygrapsus marmoratus) collected in the Azores Archipelago, Portugal (one site near a 16th-century shipwreck and others in locations further away). Mercury analyses indicated that the sediments and species from the shipwreck area had significantly higher mercury levels than the other areas. Fine sediments showed values above those established in sediment quality guidelines; however, considering the mercury concentration of the total sediment fraction, adverse biological effects are not expected to occur. Moreover, increased mercury concentration from primary producers to consumers reinforced the biomagnification potential of this metal. [ABSTRACT FROM AUTHOR]

Landasan Ulin is a center for vegetable production, and it has an important role in producing vegetables for the city of Banjarbaru. Agricultural soil in this study was assessed for heavy metal contamination using the geoaccumulation index (Igeo), contamination factor (Cf i), the degree of contamination (Cd), the degree of modified contamination (mCd), and the Pollution Load Index (PLI) as well as magnetic susceptibility. Samples were collected from topsoil and analyzed using magnetic susceptibility and Atomic Absorption Spectrophotometer (AAS). The average concentration of heavy metals in the sampling area A is Fe>Zn>Mn>Cu>Hg, and the area B is Fe>Mn>Zn>Cu>Hg. Magnetic susceptibility values in area A is higher than in area B and the value of magnetic susceptibility can be used as a proxy for monitoring heavy metal concentrations, especially Zn in this area. Zn and Cu exceeded the threshold set by the Indonesian Standards Institute. Igeo results show that the research area is moderately contaminated with Cu, Zn, and Hg. According to Cf i, the soil was classified as low contaminated with Fe, Zn, Cu, Mn, and Hg, as well as Cd and mCd. The PLI results show that in both area, drastic corrective action is not required. [ABSTRACT FROM AUTHOR]

The level of metallic (Cd, Ni, Fe, Pb, Cu) contamination in the sampled sediments of five stations (S1, S2, S3, S4 and S5) from Woji creek bed between August and October 2019 was appraised using pollution load index (PLI), contamination factor (CF) and geoaccumulation index (Igeo). Results from the sediment analysis showed that Cd was not detected in stations 1, 3 and 5 in September, however, there was a high concentration of Cd in station 3 in October (43.590 ± 2.013 mg/kg). The concentration of Ni was highest in station 4 in August (247.682 ± 6.026 mg/kg). The mean spatial concentration of Pb ranged from 57.774 ± 75.647 mg/kg in October to 344.153 ± 112.184 mg/kg in August. Spatially, the highest concentration of Fe was measured in August (23.945 ± 17.828 mg/kg). Station 2 had the lowest concentration of Fe in the sediment temporally (5.667 ± 6.381 mg/kg) while station 3 had the highest concentration (19.496 ± 24.090 mg/kg); 37.188 ± 27.821 mg/kg (station 3) was the highest mean temporal concentration Cu, while station 2 had the lowest mean concentration of Cu (0.471 ± 0.358 mg/kg).The PLI values were in the trend: S3 (2.58 x 1015) >S4 (5.29 x 1014) > S1 (3.52 x 1014) > S5 (3.71 x 1013) > S2 (4.64 x 1012).These results indicated that the highest concentration of studied metals was found in S3 (except for Ni in S4), which emphasised the possible input of metallic matter into the sediment from the various operations along the creek connected with the disposal of metallic particulate wastes. All the metals present in the sampled sediments (except for Cu in S2) had concentrations between threshold effect level (TEL) and probable effect levels (PEL), which suggests the influence of unfavourable biological processes taking place from time to time. [ABSTRACT FROM AUTHOR]

This study was conducted on some agricultural clayey soils in Kafr El-Sheikh governorate in order to explore the effect of different sources of heavy metal pollution on the type and quantity of some tested metals (Cu, Cr, Mn, Zn and Pb) in these soils. Also, to identify the distribution of these metals among the different components of tested soils. The different indicators (Ci f, Igeo and Ei f) of pollution with these elements were calculated in each soil to determine the significance of the pollution of each metal under different pollution conditions. The results of this study showed a difference in the content and type of tested metals (Cu, Cr, Mn, Zn and Pb) compared to the control (virgin soil). Consequently, the data of this study showed a difference in the values of the pollution indicators for each metal in the tested soils, affected by the different sources of pollution and amount of heavy polluting metals that reached to each soil. Likewise, the results of the chemical forms for each tested metal showed that they are concentrated in each of the following soil fractions F3 and F4. [ABSTRACT FROM AUTHOR]

Coastal environmental assessment techniques have evolved into one of the most important fields for the long-term development and management of coastal zones. So, the overall aim of the present investigation was to provide effective approaches for making informed decisions about the Gamasa coast sediment quality. Over a two-year investigation, sediment samples were meticulously collected from the Gamasa estuary and littoral shelf. The inductively coupled plasma mass spectra (ICP-MS) was used to the total concentrations of Al, Fe, Ti, Mg, Mn, Cu, P, V, Ba, Cr, Sr, Co, Ni, Zn, Pb, Zr, and Ce. Single elements environmental pollution indices including the geoaccumulation index (Igeo), contamination factor (CF), and enrichment factor (EF), as well as multi-elements pollution indices comprising the potential ecological risk index (RI), degree of contamination (Dc), and pollution load index (PLI) were used to assess the sediment and the various geo-environmental variables affecting the Mediterranean coastal system. Furthermore, the Dc, PLI, and RI were estimated using the random forest (RF) and Back-Propagation Neural Network (BPNN) depending on the selected elements. According to the Dc results, all the investigated sediment samples categories were considerably contaminated. Cr, Co, Ni, Cu, Zr, V, Zn, P, and Mn showed remarkable enrichment in sediment samples and were originated from anthropogenic sources based on the CF, EF, and Igeo data. Moreover, the RI findings revealed that all the samples tested pose a low ecologically risk. Meanwhile, based on PLI, 70% of the Gamasa estuary samples were polluted, while 93.75% of littoral shelf sediment was unpolluted. The BPNNs -PCs-CD-17 model performed the best and demonstrated a better association between exceptional qualities and CD. With R2 values of 1.00 for calibration (Cal.) and 1.00 for validation (Val.). The BPNNs -PCs-PLI-17 models performed the best in terms of measuring PLI with respective R2 values of 1.00 and 0.98 for the Cal. and Val. datasets. The findings showed that the RF and BPNN models may be used to precisely quantify the pollution indices (Dc, PLI, and RI) in calibration (Cal.) and validation (Val.) datasets utilizing potentially toxic elements of surface sediment. [ABSTRACT FROM AUTHOR]

Soil is a naturally occurring non-renewable resource, and good soil quality is a prerequisite for the survival of plants, animals and humans. Soil quality depends on the content and distribution of trace elements. Gold mining in the Witwatersrand Basin in South Africa left behind enormous unrehabilitated mining waste tailings near the City of Johannesburg that are contaminated by trace elements. Heavy metals change the physical and chemical properties of the soil derived from the mining waste material, consequently disturbing the normal functions of the soil and posing a potential health risk to plants, animals, and humans. To assess soil quality from abandoned historical gold mine residues, three conglomerate samples were petrologically examined using hand specimen, polished thin sections viewed under a reflected light microscope, and X-ray diffraction, to determine the mineralogical composition. The minerals include quartz, mica, chlorite, calcite and sulphides. Geochemical data of major elements measured by weight percent (wt%) were generated using X-ray fluorescence (XRF) technique and are NiO < Cr2O3 < V2O5 < ZrO2 < MnO < P2O5 < TiO2 < Al2O3 < CaO < MgO < Na2O < K2O < Fe2O3 < SiO2. The geochemistry of trace elements, pH, and electrical conductivity (EC), were determined from 21 soil samples. The samples were collected from 30 to 150 cm depths from nine sites and investigated using inductively coupled plasma optical emission spectroscopy (ICP-EOS) and XRF. ICP-EOS data (mg/kg): Fe > S > Cu > Mn > Cr > Zn > Ni > Co > Mo > P, and XRF data (mg/kg): S > F > Cl > V > Cr > Zn > Co > Cu > Ni > Mo. The trace elements data are variable in the tailing soil than in the crustal background soil. According to ICP-EOS data, the surveyed sites show increased Cu content, pH values of 1.9–5.3 and EC values of 43–679 mS/m, indicating soil contamination.

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]

To assess the vulnerability of Araromi residents to toxic (trace) metal pollution, we estimated the ecological risk of the sediments in the coastal area. The concentration of the metals (ppm) followed the trend: Fe (16,265–90,512) > Mn (116.3–1657) > Zn (16.5–338) > Cu (2.62–75.5) > Cr (4.5–29.25) > Pb (2–104.5) > Co (2.5–26) > Ni (1.45–22.75) > Cd (0.0015–1.5). Sediments from Oke Siri‐2, Idi Gbengben‐1, Oke Meji, Idi Gbengben‐3, and Ola Baba evidenced significant or extremely high enrichments. The degree of pollution of the trace metal was Pb > Cd > Zn > Fe > Mn > Co > Cu > Cr > Ni. Furthermore, the derived geoaccumulation index and contamination factor revealed that Pb, Cd, and Zn exhibited low‐high pollution levels. In contrast, Cr, Ni, Cu, Mn, Fe, and Co showed zero potential for ecological risks. The hazard index suggested that children and adults were not susceptible to any potential carcinogenic and noncarcinogenic effects. Also, the consensus‐based sediment quality guidelines revealed no adverse effects caused by toxic metals as the metals have values below the probable effect concentrations. [ABSTRACT FROM AUTHOR]

During the Spanish colonial era, ships frequently transported mercury across the Atlantic to the New World to be used in gold mining. As many of those eventually sank, shipwrecks may represent a local source of mercury contamination in the marine environment. In this context, evaluating mercury contamination in coastal sediments and mercury magnification in marine food webs is crucial for understanding mercury dynamics and estimating exposure to marine life in locations where shipwrecks occurred. This study investigated mercury concentration present in coastal sediments and biota from three distinct groups: macroalgae (Asparagopsis armata and Ulva lactuca), gastropods (Littorina striata and Patella candei gomesii) and crustaceans (Palaemon elegans and Pachygrapsus marmoratus) collected in the Azores Archipelago, Portugal (one site near a 16th-century shipwreck and others in locations further away). Mercury analyses indicated that the sediments and species from the shipwreck area had significantly higher mercury levels than the other areas. Fine sediments showed values above those established in sediment quality guidelines; however, considering the mercury concentration of the total sediment fraction, adverse biological effects are not expected to occur. Moreover, increased mercury concentration from primary producers to consumers reinforced the biomagnification potential of this metal.

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]

Landfills, old and abandoned mines, industrial sites, heaps, sludge ponds and other sources of pollution represent environmental threats and are characterized as chemical time bombs. This work is focused on the evaluation of soil contamination by risk elements using various indices (geoaccumulation index--Igeo, enrichment factor--EF, contamination factor--Cif and degree of contamination--Cd). These selected agrarian problem areas are located in Slovakia, especially in the air pollution field of landfills consisting of power plant fly ash, tannery and footwear wastes, leachate (lúženec), iron ore slag, waste from metallurgy and sludge ponds in which coal sludge waste is deposited and waste from ore treatment. Nine research sites in the agrarian region of Slovak Republic were monitored. Ten risk elements (Fe, Mn, Zn, Cu, Co, Ni, Cr, Pb, Cd and Hg) and pH/H2O were included in this study and were determined in surface soils (of 0.05 m to 0.15 m) using atomic absorption spectrometry (AAS). Our study showed the highest exceedance of the limit values of risk elements in the order Ni (51.85 times) > Co (25.47 times) > Cd (13.70 times) > Cu (12.78 times) > Cr (8.37 times) > Fe (8.26 times) > Hg (7.94 times) > Zn (5.71 times) > Pb (4.63 times). The content of risk elements increased based on the average values of Igeo in the order of Cr < Hg < Zn < Pb < Ni < Cu < Cd. Igeo values for cadmium indicated mild-to-extreme contamination at all sites. We found the most significant enrichment in the order of Cd > Cu > Pb > Ni > Zn > Hg > Cr. EF values for cadmium indicated extremely high enrichment; the Cif and Cd values indicated a very high degree of soil contamination near the nickel smelter landfill, an industrial metallurgical plant and old but active mines. The studied areas pose a serious danger not only to the soil but also to groundwater and biota due to the prevailing low soil reaction, which increases the mobility of toxic elements. The study provides important results for the development of effective strategies for the control and remediation of endangered areas. [ABSTRACT FROM AUTHOR]

Background: Contamination of soil with heavy metals is an alarming issue around the world. Therefore, this study aimed to assess the contamination status of heavy metals in the soil of Mongla industrial area, Bangladesh. Methods: Soil samples were randomly collected from 20 sites and digested by wet digestion method. The concentrations of heavy metals (Mn, Fe, Cu, Zn, Cd, and Pb) were determined using atomic absorption spectrophotometer (AAS). The quality of soil was assessed based on the contamination factor (CF), geoaccumulation index (Igeo), enrichment factor (EF), and ecological risk index factor (ERIF) analyses. Results: The average concentrations of Mn, Fe, Cu, Zn, Cd, and Pb were obtained to be 258.08 ± 51.61, 3736.90 ± 322.17, 19.55 ± 6.49, 66.76 ± 18.32, 0.59 ± 0.13, and 10.40 ± 1.49 mg kg-1, respectively, which were below the permissible limit. The highest value of CF (0.74 ± 0.16), Igeo (0.35 ± 0.34), EF (24.86 ± 6.27), and PERIF (22.11 ± 4.81) was observed for Cd. The pollution of CF, Igeo, EF, and ERIF was classified as very severely polluted, unpolluted to moderately polluted, strongly to extremely polluted, and slightly polluted, respectively, with these heavy metals due to anthropogenic activities. One-way ANOVA indicated a significant difference between Zn and Cd concentrations (P < 0.05), whereas Pearson correlation showed a positive correlation between Zn-Pb (P = 0.01) and Fe-Zn (P = 0.05). Conclusion: There are different classes of contamination with heavy metals in the study area. Therefore, necessary steps should be taken and people’s awareness of the soil pollution should be raised.

Coastal environmental assessment techniques have evolved into one of the most important fields for the long-term development and management of coastal zones. So, the overall aim of the present investigation was to provide effective approaches for making informed decisions about the Gamasa coast sediment quality. Over a two-year investigation, sediment samples were meticulously collected from the Gamasa estuary and littoral shelf. The inductively coupled plasma mass spectra (ICP-MS) was used to the total concentrations of Al, Fe, Ti, Mg, Mn, Cu, P, V, Ba, Cr, Sr, Co, Ni, Zn, Pb, Zr, and Ce. Single elements environmental pollution indices including the geoaccumulation index (Igeo), contamination factor (CF), and enrichment factor (EF), as well as multi-elements pollution indices comprising the potential ecological risk index (RI), degree of contamination (Dc), and pollution load index (PLI) were used to assess the sediment and the various geo-environmental variables affecting the Mediterranean coastal system. Furthermore, the Dc, PLI, and RI were estimated using the random forest (RF) and Back-Propagation Neural Network (BPNN) depending on the selected elements. According to the Dc results, all the investigated sediment samples categories were considerably contaminated. Cr, Co, Ni, Cu, Zr, V, Zn, P, and Mn showed remarkable enrichment in sediment samples and were originated from anthropogenic sources based on the CF, EF, and Igeo data. Moreover, the RI findings revealed that all the samples tested pose a low ecologically risk. Meanwhile, based on PLI, 70% of the Gamasa estuary samples were polluted, while 93.75% of littoral shelf sediment was unpolluted. The BPNNs -PCs-CD-17 model performed the best and demonstrated a better association between exceptional qualities and CD. With R2 values of 1.00 for calibration (Cal.) and 1.00 for validation (Val.). The BPNNs -PCs-PLI-17 models performed the best in terms of measuring PLI with respective R2 values of 1.00 and 0.98 for the Cal. and Val. datasets. The findings showed that the RF and BPNN models may be used to precisely quantify the pollution indices (Dc, PLI, and RI) in calibration (Cal.) and validation (Val.) datasets utilizing potentially toxic elements of surface sediment.

The quality of soils polluted by trace elements around the facilities with the Cu and Zn smelting activities and the post-flotation tailings pond from copper industry were assessed. The level of the contamination of soils was determined on the basis of the contamination factor and the geoaccumulation index. The geoaccumulation index allows to distinguish more degrees of soil contamination and simplifies the assessment of the useable value of soil. The degrees of soil contamination and the pollution load index were shown. It has been shown that the pollution indices are a useful tool in describing the soil quality and planning corrective actions in the areas contaminated as a result of industrial activity. Histograms of pollution indices were used in order to detect the distribution of trace elements in soils. The content of metals in biomass was assessed using bioaccumulation indices. Triticum L. and Brassica napus L. show low bioaccumulation of studied metals in cereal plants. The correlations were used in order to detect the relationship among trace elements in soil as well as the relationship of metal (soil)-metal (plant) and metal bioaccumulation (plant)-metal (soil). The highest values of indices were recorded for the Oława smelter, presumably due to the long operation period before technological changes limiting the emission of pollutants were introduced. This research area was classified as very highly contaminated with all trace elements. Soils around other facilities are at least moderately contaminated. [ABSTRACT FROM AUTHOR]

This research intends to offer a scientific foundation for environmental monitoring and early warning which will aid in the environmental protection management of Qaroun Lake. Qaroun Lake is increasingly influenced by untreated wastewater discharge from many anthropogenic activities, making it vulnerable to pollution. For that, six environmental pollution indices, namely contamination factor (Cf), enrichment factor (EF), geo-accumulation index (Igeo), degree of contamination (Dc), pollution load index (PLI), and potential ecological risk index (RI), were utilized to assess the bottom sediment and to determine the different geo-environmental variables affecting the lake system. Cluster analysis (CA), and principal component analysis (PCA) were used to explore the potential pollution sources of heavy metal. Moreover, the efficiency of partial least-square regression (PLSR) and multiple linear regression (MLR) were tested to assess the Dc, PLI, and RI depending on the selected elements. The sediment samples were carefully collected from 16 locations of Qaroun Lake in two investigated years in 2018 and 2019. Total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Ga, Hf, Li, Mg, Mn, Mo, Ni, P, Pb, Sb, Se, Zn, and Zr were quantified using inductively coupled plasma mass spectra (ICP-MS). According to the Cf, EF, and Igeo results, As, Cd, Ga, Hf, P, Sb, Se, and Zr demonstrated significant enrichment in sediment and were derived from anthropogenic sources. According to Dc results, all collected samples were categorized under a very high degree of contamination. Further, the results of RI showed that the lake is at very high ecological risk. Meanwhile, the PLI data indicated 59% of lake was polluted and 41% had PLI < 1. The PLSR and MLR models based on studied elements presented the highest efficiency as alternative approaches to assess the Dc, PLI, and RI of sediments. For examples, the validation (Val.) models presented the best performance of these indices, with R2val = 0.948–0.989 and with model accuracy ACCv = 0.984–0.999 for PLSR, and with R2val = 0.760–0.979 and with ACCv = 0.867–0.984 for MLR. Both models for Dc, PLI, and RI showed that there was no clear overfitting or underfitting between measuring, calibrating, and validating datasets. Finally, the combinations of Cf, EF, Igeo, PLI, Dc, RI, CA, PCA, PLSR, and MLR approaches represent valuable and applicable methods for assessing the risk of potentially harmful elemental contamination in the sediment of Qaroun Lake.

Landfills, old and abandoned mines, industrial sites, heaps, sludge ponds and other sources of pollution represent environmental threats and are characterized as chemical time bombs. This work is focused on the evaluation of soil contamination by risk elements using various indices (geoaccumulation index—Igeo, enrichment factor—EF, contamination factor—Cif and degree of contamination—Cd). These selected agrarian problem areas are located in Slovakia, especially in the air pollution field of landfills consisting of power plant fly ash, tannery and footwear wastes, leachate (lúženec), iron ore slag, waste from metallurgy and sludge ponds in which coal sludge waste is deposited and waste from ore treatment. Nine research sites in the agrarian region of Slovak Republic were monitored. Ten risk elements (Fe, Mn, Zn, Cu, Co, Ni, Cr, Pb, Cd and Hg) and pH/H2O were included in this study and were determined in surface soils (of 0.05 m to 0.15 m) using atomic absorption spectrometry (AAS). Our study showed the highest exceedance of the limit values of risk elements in the order Ni (51.85 times) > Co (25.47 times) > Cd (13.70 times) > Cu (12.78 times) > Cr (8.37 times) > Fe (8.26 times) > Hg (7.94 times) > Zn (5.71 times) > Pb (4.63 times). The content of risk elements increased based on the average values of Igeo in the order of Cr < Hg < Zn < Pb < Ni < Cu < Cd. Igeo values for cadmium indicated mild-to-extreme contamination at all sites. We found the most significant enrichment in the order of Cd > Cu > Pb > Ni > Zn > Hg > Cr. EF values for cadmium indicated extremely high enrichment; the Cif and Cd values indicated a very high degree of soil contamination near the nickel smelter landfill, an industrial metallurgical plant and old but active mines. The studied areas pose a serious danger not only to the soil but also to groundwater and biota due to the prevailing low soil reaction, which increases the mobility of toxic elements. The study provides important results for the development of effective strategies for the control and remediation of endangered areas.

The mercury content and the contamination characteristics of water, sediments, edible muscles of a non-piscivorous fish (Oreochromis nilotica Linnaeus 1758 [Cichlidae]) and yams (Dioscorea alata) from Namukombe stream in Busia gold district of Uganda were evaluated. Human health risk assessment from consumption of contaminated fish and yams as well as contact with contaminated sediments from the stream were performed. Forty-eight (48) samples of water (n = 12), sediments (n = 12), fish (n = 12) and yams (n = 12) were taken at intervals of 10 m from three gold recovery sites located at up, middle and down sluices of the stream and analyzed for total mercury (THg) using US EPA method 1631. Results (presented as means ± standard deviations) showed that water in the stream is polluted with mercury in the range of < detection limit to 1.21 ± 0.040 mg/L while sediments contain mean THg from < detection limit to 0.14 ± 0.040 ugg−1. Mean THg content of the edible muscles of O. nilotica ranged from < detection limit to 0.11 ± 0.014 ugg−1while D. alata contained from < detection limit to 0.30 ± 0.173 ugg−1mean THg. The estimated daily intake ranged from 0.0049 ugg−1day−1 to 0.0183 ugg−1day−1 and 0.0200 ugg−1day-1 to 0.0730 ugg−1day−1 for fish consumed by adults and children respectively. The corresponding health risk indices ranged from 0.0123 to 0.0458 and 0.0500 to 0.1830. Estimated daily intake was from 0.0042 ugg−1day−1 to 0.1279 ugg−1day−1 and 0.0130 ugg−1day−1 to 0.3940 ugg−1day−1 for D. alata consumed by adults and children respectively. The health risk indices recorded were from 0.011 to 0.320 and 0.033 to 0.985 for adults and children respectively. The mean THg content of the sediments, edible muscles of O. nilotica and D. alata were within acceptable WHO/US EPA limits. About 91.7% of the water samples had mean THg above US EPA maximum permissible limit for mercury in drinking water. Consumption of D. alata grown within 5 m radius up sluice of Namukombe stream may pose deleterious health risks as reflected by the health risk index of 0.985 being very close to one. From the pollution and risk assessments, mercury use should be delimited in Syanyonja artisanal gold mining areas. A solution to abolish mercury-based gold mining in the area needs to be sought as soon as possible to avert the accentuating health, economic and ecological disaster arising from the continuous discharge of mercury into the surrounding areas. Other mercury-free gold recovering methods such as use of borax, sluice boxes and direct panning should be encouraged. Waste management system for contaminated wastewater, used mercury bottles and tailings should be centralized. [ABSTRACT FROM AUTHOR]

The present study focuses on the risk assessment of heavy metal contamination in aquatic ecosystems by evaluating the current situation of heavy metals in seven locations (North Amer El Bahry, Amer, Bakr, Ras Gharib, July Water Floud, Ras Shokeir, and El Marageen) along the Suez Gulf coast that are well-known representative sites for petroleum activities in Egypt. One hundred and forty-six samples of surface sediments were carefully collected from twenty-seven profiles in the intertidal and surf zone. The hydrochemical parameters, such as pH and salinity (S‰), were measured during sample collection. The mineralogy study was carried out by an X-ray diffractometer (XRD), and the concentrations of Al, Mn, Fe, Cr, Cu, Co, Zn, Cd, and Pb were determined using inductively coupled plasma mass spectra (ICP-MS). The ecological risks of heavy metals were assessed by applying the contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI). The mineralogical composition mainly comprised quartz, dolomites, calcite, and feldspars. The average concentrations of the detected heavy metals, in descending order, were Al > Fe > Mn > Cr > Pb > Cu > Zn > Ni > Co > Cd. A non-significant or negative relationship between the heavy metal concentration in the samples and their textural grain size characteristics was observed. The coastal surface sediment samples of the Suez Gulf contained lower concentrations of heavy metals than those published for other regions in the world with petroleum activities, except for Al, Mn, and Cr. The results for the CF, EF, and Igeo showed that Cd and Pb have severe enrichment in surface sediment and are derived from anthropogenic sources, while Al, Mn, Fe, Cr, Co, Ni, Cu, and Zn originate from natural sources. By comparison, the PLI and RI results indicate that the North Amer El Bahry and July Water Floud are considered polluted areas due to their petroleum activities. The continuous monitoring and assessment of pollutants in the Suez Gulf will aid in the protection of the environment and the sustainability of resources.

Several tools have been developed and applied to evaluate the metal pollution status of sediments and predict their potential ecological risk assessment. To date, a comprehensive relationship between the information given by these sediment tools for predicting metal bioavailability and the effective toxicity observed is lacking. In this work, the possible inter-correlations between the data outcoming from using several qualitative evaluation tools of the sediment contamination (contamination factor, CF, the enrichment factor, EF, or the geoaccumulation index, Igeo), metal speciation on sediments (evaluated by the modified BCR sequential extraction procedure) and free metal concentrations in pore waters were studied. It was also our aim to evaluate if these assessment tools could be used for predicting the pore waters toxicity data as toxicity proxy. Principal component analysis and cluster analysis revealed that two quality indices used (CF and EF) were highly correlatable with the more labile fractions from BCR sediment speciation. However, neither of these parameters did correlate with the toxicity of pore waters measured by the chronic toxicity (72 h) in Pseudokirchneriella subcapitata . In contrast, the toxic effects of the given total metal load in sediments were better evaluated by using an additive metal approach using pore water free metal concentrations. [ABSTRACT FROM AUTHOR]

São Domingos belongs among the most important historic Iberian Pyrite Belt Cu mines. The anthrosoil is contaminated by a very high content of heavy metals and metalloids. The study was focused on evaluating the interaction of some chemical elements (Ca, Mg, Fe, Mn, Cu, Pb, Zn, Ag, Cd, Ni, Co, As, Sb) in the system soil vs. five autochthonous dominant plant species: Pinus pinaster Aiton, Quercus rotundifolia Lam., Agrostis sp., Juncus conglomeratus L. and Juncus effusus L. The plants are heavily contaminated by Cu, Pb, As and Zn. The bioconcentration factor proved that they exhibit features of metal tolerant excluders. The trees are accumulators of Ag, whereas the graminoids are hyper-accumulators of Ag and Juncus effusus of Co. The translocation factor confirmed that the selected elements are immobilised in the roots except for Mn and Zn in Pinus pinaster and Mn in Quercus rotundifolia and Juncus conglomeratus. The bioaccumulation of Mn, Zn and Cu at low pH increases. The increased content of Ca and Mg in the soil inhibits, in the case of some metals and metalloids, their intake to plants. Although the studied plants, despite their fitness and vitality at the contaminated sites, are not suitable for phytoextraction (except Co and Ag), they can be used for phytostabilisation at the mining habitats. [ABSTRACT FROM AUTHOR]

Zambia's Kafue River receives wastes from various sources, resulting in metal pollution. This study determined the degree of contamination of 13 metals (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Hg and Pb) in Kafue River sediment and the associated ecological risks at six sites in three different seasons. The level of contamination for most metals showed significant site and seasonal differences. The contamination factor and pollution load index indicated that concentrations of most metals particularly copper (Cu), cobalt (Co), manganese (Mn) and arsenic (As) were very high at sites within the Copperbelt mining area. The geoaccumulation index showed an absence of anthropogenic enrichment with Cd and Hg at all the study sites and extreme anthropogenic enrichment with Cu at sites in the Copperbelt mining area. Potential ecological risk showed that Cu and As were likely to cause adverse biological effects to aquatic organisms in the Copperbelt mining region of the Kafue River. [ABSTRACT FROM AUTHOR]

Magnetic susceptibility is used worldwide as a measure of concentration of (ferri)magnetic minerals in soil, sediment and dust. In soils, these minerals are of various origins: air-derived particulate pollution, parent rocks or pedogenesis. Human activity causes different changes in the content of magnetic minerals as well as their spatial and vertical distribution in soil profiles. Magnetic minerals are characterised by an affinity to other elements occurring in the soil, e.g. heavy metals. Therefore magnetic susceptibility has been widely applied as approximation of soil contamination by heavy metals. The archival soil samples collected from different soil horizons in the territory of the Free State of Saxony (Germany) were subjected to magnetic susceptibility measurements using Bartington MS2B. Additionally, samples were chemically analysed in order to determine the content of Fe, Mn, Ni, Cu, Zn, Cd, Pb and As using a method of atomic absorption spectroscopy (AAS). The contamination factor (CF) and geoaccumulation index (I geo ) were applied for assessment of soil contamination with particular potentially toxic elements (PTE), while the more general pollution load index (PLI) was used for comparison between different geographic sites. Values of magnetic susceptibility varied from 16.6 to 1382 × 10 − 8 m 3 kg − 1 in organic soil horizons and from 0.1 to 1580 × 10 − 8 m 3 kg − 1 in deeper layers. Significant and relatively high correlation coefficients between soil magnetic susceptibility and the content of some heavy metals indicated that they were of the similar origin as (ferri)magnetic minerals occurring in soil (viz. industrial pollution, parent rocks or pedogenic processes). PLI distribution over the entire area of Saxony corresponds well with the magnetic susceptibility distribution, especially in the organic soil horizon. The indices qualify the northeastern part of Saxony as extremely or heavily polluted in the organic soil horizon (under forests) with decreasing contamination in deeper layers, being classified as non-polluted to moderately polluted. However, the prevailing Saxony area is characterised by low and moderate contamination by potentially toxic elements, such as heavy metals. [ABSTRACT FROM AUTHOR]

Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS). The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells) and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated) SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use) and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix. [ABSTRACT FROM AUTHOR]

The concentrations of heavy metals in soft sediments of the Manavgat and Lara regions in Antalya, Türkiye were investigated to assess contamination levels and their potential sources, followed by multivariate statistical analysis and generation of spatial distribution maps. Results showed low contamination levels for As, Zn, and Cu, moderate contamination for Pb, Ni, and Mn, and very high accumulation for Co and Cr. Geoaccumulation index (Igeo) and contamination factor (CF) analyses revealed moderate enrichment for Mn and low enrichment for As, indicating no human-induced contamination in Cu, Pb, Zn, Mn, and As, while Ni, Co, and Cr originated mainly from agriculture. The maximum modified degree of contamination (mCd) value was at an extreme high level, with an average mCd of 4.12 indicating high contamination. Maximum pollution load index (PLI) value was 3.13, indicating high-grade pollution and an average value of 1.7 indicating moderate pollution. [Display omitted] • Contamination moderate for Pb, cc Cr • Enrichment moderate for Mn, low for As, Ni, Co and Cr based on geoaccumulation index • Maximum modified degree of contamination significantly high with an average mCd of 4.12 • Maximum pollution load index value 3.13 (high pollution) with 1.7 (moderate pollution) on average • Phosphorus deficiency derived from Al 2 O 3 , clay minerals, FeOOH and TOC, limiting plant growth [ABSTRACT FROM AUTHOR]

The contents of Cu, Pb, Zn, Cd, Cr, Hg and As in the surface sediments of over 668 sites were monitored in a comprehensive program for assessing the degree of heavy-metal pollution and adverse biological effects of the offshore sediments in China. The contamination factor and geoaccumulation index indicated that As and Pb might be two of the most influential pollution loading in these metals. Cluster analysis separated 19 areas in China's near seas into 7 groups with different pollution characteristic, where the sediments along Zhejiang coast were the most highly-contaminated. Based on biological adverse effects index and sediment quality guideline for As, nearly half of sites in China's near seas induced slight adverse biological effects. With correlation analysis, self-organizing map and factor analysis, different sources as well as various adsorption mechanisms/anthropogenic factors were suggested to be important roles in altering the concentration of heavy metals in the sediments. [ABSTRACT FROM AUTHOR]

The pollution load due to metal contamination in the sediments of urban wetlands (Dhanbad, India) due to illegal release of domestic and industrial wastewater was studied by using various geochemical indices, such as contamination factor (C), degree of contamination (C), modified degree of contamination (mC), pollution load index (PLI) and geoaccumulation index (I) for Cu, Co, Cd, Cr and Mn. Cluster analysis (CA) and Principal component analysis (PCA) of metals present in wetland sediments were carried out to assess their origin and relationship with each other. The C values for different metals in the wetlands under investigation indicated low to very high level of pollution (C ranged between 0.02 and 14.15) with highest C (14.15) for Cd. The wetland receiving both domestic and industrial wastewater had the highest values of C, mC and PLI as 17.48, 3.49 and 1.03 respectively. [ABSTRACT FROM AUTHOR]

The Bernam River is one of the most important rivers in Malaysia in that it provides water for industries and agriculture located along its banks. The present study was conducted to assess the level of contamination of heavy metals (Cd, Ni, Cr, Sn, and Fe) in surface sediments in the Bernam River. Nine surface sediment samples were collected from the lower, middle, and upper courses of the river. The results indicated that the concentrations of the metals decreased in the order of Sn > Cr > Ni > Fe > Cd (56.35, 14.90, 5.3, 4.6, and 0.62 μg/g dry weight). Bernam River sediments have moderate to severe enrichment for Sn, moderate for Cd, and no enrichment for Cr, Ni, and Fe. The contamination factor (CF) results demonstrated that Cd and Sn are responsible for the high contamination. The pollution load index (PLI), for all the sampling sites, suggests that the sampling stations were generally unpolluted with the exception of the Bagan Tepi Sungai, Sabak Bernam, and Tanjom Malim stations. Multivariate techniques including Pearson's correlation and hierarchical cluster analysis were used to apportion the various sources of the metals. The results suggested that the sediment samples collected from the upper course of the river had lower metal concentrations, while sediments in the middle and lower courses of the river had higher metal concentrations. Therefore, our results can be useful as a baseline data for government bodies to adopt corrective measure on the issues related to heavy metal pollution in the Bernam River in the future. [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 present study was conducted along three major highways namely State Highway (SH49), National Highway (NH66 and 45A) connecting Puducherry (India) for assessing heavy metals and total petroleum hydrocarbon contamination from surface soils in close proximity at a depth of 0-15 cm into automobile repair workshops and agricultural fields located beside the highways. Contamination levels of copper, lead, zinc, manganese, cadmium and chromium were assessed in the surface sediments soil on the basis of geoaccumulation index, contamination factors and spatial variability. The results revealed that sampling sites in the proximity to automobile workshops were moderately to considerably pollution impacted as compared to soil from agricultural fields along highways suggesting a direct influence of anthropogenic activities on levels of contamination. The concentration of heavy metals in the surface soil of automobile workshops close to NH66 ranged between 143.07 and 319.28 mg kg copper; 68.72-396.41 mg kg lead; 162.42-284.91 mg kg zinc; 212.72-401.33 mg kg manganese; 0.12-15.41 mg kg chromium; and 0.73-1.06 mg kg cadmium in dry soil. However, in agricultural fields, the concentrations varied between 33.68 and 66.62 mg kg copper; 27.22-73.66 mg kg lead; 26.24-75.59 mg kg zinc; 137.88-242.07 mg kg manganese; 0-0.21 mg kg chromium; and 1.04-1.58 mg kg cadmium. Total petroleum hydrocarbon concentration near automobile workshops ranged between 90.72 and 121.79 mg kg in contrast to 44.94-83.4 mg kg in agricultural fields. Total petroleum hydrocarbon concentration indicated strong positive correlation with zinc ( r = 0.811), copper ( r = 0.761); lead ( r = 0.642), Mn ( r = 0.571), chromium ( r = 0.530) and strong negative correlation with cadmium ( r = −0.765) at 0.05 significance level. Pearson correlation indicated a strong association of total petroleum hydrocarbon with copper, lead and zinc suggesting that the metal contaminants from roadside surface soil had emanated from a common source. [ABSTRACT FROM AUTHOR]

Fifty four sediment samples representing pre and post-monsoon seasons were collected along a transect from off Kochi, lying between the latitudes 9°57′59.5″-9°54′30.4″ and longitudes 76°11′7.04″-75°38′50.3″ of the South eastern Arabian Sea. The present study investigates the levels of trace metals (Zn, Cd, Pb, Cu, Fe, Ni, Mn, Co and Cr), total organic carbon (TOC), total inorganic carbon (TIC), elemental composition and grain size to assess the extent of environmental pollution and to discuss the distribution of these trace metals in the surficial sediments. Sediment pollution assessment was done using the Contamination factor (C.F), Geoaccumulation Index (Igeo), Enrichment Factor (EF), and Pollution Load Index (PLI). The majority of trace metals analysed in this study exhibited the highest concentrations at stations 1, 2 and 3 where the land-based anthropogenic input was found to be maximum. • This study assessed spatial and temporal variation of trace metals, TOC, TIC, elemental composition and grain size in off Kochi sediments. • The majority of trace metals in this study exhibited the highest concentrations at stations 1, 2 and 3 where the land-based anthropogenic input was maximum. • According to the contamination factor, the coastal environment was moderately polluted with Ni, Cr and Zn. • The results draw special attention to Cochin, the second biggest industrial city along the west coast of India. [ABSTRACT FROM AUTHOR]