Metal Concentrations In Sediments Research Articles

Historical gold mining increased metal(loid) concentrations in lake sediments from Nova Scotia, Canada

Historical gold mining operations between the 1860s and 1940s have left substantial quantities of arsenic- and mercury-rich tailings near abandoned mines in remote and urban areas of Nova Scotia, Canada. Large amounts of materials from the tailings have entered the surface waters of downstream aquatic ecosystems at concentrations that present a risk to benthos. We used paleolimnological approaches to examine long-term trends in sedimentary metal(loid) concentrations, assess potential sediment toxicity, and determine if geochemical recovery has occurred at four lakes located downstream of three productive gold-mining districts. During the historical mining era, sedimentary total arsenic and mercury concentrations and enrichment factors increased substantially at all downstream lakes that received inputs from tailings. Similarly, chromium, lead, and zinc concentrations increased in the sediments after mining activities began and the urbanization that followed. The calculated probable effects of concentration quotients (PEC-Qs) for sediments exceeded the probable biological effects threshold (PEC-Q > 2) during the mining era. Although sedimentary metal(loid) concentrations have decreased for most elements in recent sediments, relatively higher PEC-Q and continued exceedance of Canadian Interim Sediment Quality Guidelines suggest that complete geochemical recovery has not occurred. It is likely that surface runoff from tailing fields, urbanization, and climate-mediated changes are impacting geochemical recovery trajectories.

Pollution indicators of heavy metals in the sediments of the Lepenc river in Kosovo

The sediments of the Lepenc River in Kosovo have been investigated, by using X-ray fluorescence (XRF) technique. The concentrations of such metals as As, Ca, Cr, Cu, Fe, K, Mn, Nb, Ni, Pb, Rb, Sr, Th, Ti, V, Y, Zn and Zr were analyzed in six different locations. The most of metals analyzed had median values higher than those in European steam sediment. Basic statistics, Pearson’s correlation and cluster analysis were performed to better explain the data of metal concentrations in the river sediments. Four groups of elements were identified by cluster analysis based on their geogenic or anthropogenic origin. The sediments were mostly contaminated with potentially toxic elements (As, Cr, Cu and Ni). The contamination factors (CF) for different metals and locations ranged from 1.8 to 5.33, and the pollution load index (PLI) from 2.42 to 3.09. Nickel and chromium contributed the most to sediment pollution, and their geoaccumulation indices (Igeo) in all locations were higher than 1. The most polluted sediment samples were in two locations, in the vicinity of a nickel mine and a cement factory.

Assessment of the status of selected heavy metals in water, sediments and a fish species (Oreochromis niloticus) of commercial value in Lake Nakuru with a focus on human health risks

AbstractThe present study presents selected water quality parameters and the levels of heavy metals in water, sediments and Nile tilapia (Oreochromis niloticus) of Lake Nakuru. Nine sediments and nine water samples, as well as 30 specimens of Nile tilapia, were collected from the northern part of the lake. Physical parameters were measured in situ using multiple probes and metres. Heavy metals were analysed using an atomic absorption spectrophotometer (AAS). The pH, dissolved oxygen concentration, temperature, salinity and electrical conductivity ranged from 9.52 to 9.72, 4.58 to 8.62 mg/L, 23.40°C to 25.7°C, 2.39‰ to 2.81‰ and 4470–5226 μs/cm, respectively. Heavy metal levels (mean ± SD) were generally low in the water samples. Chromium values ranged between 7.16 and 9.19 mg/kg dw in sediment samples, and between 3.7 and 13.06 mg/kg dw in fish samples. Lead values ranged between 12.5 and 31.04 mg/kg dw in sediment samples and 4.06 and 9.95 mg/kg dw in fish samples. Arsenic values ranged between 9.5 and 21.7 mg/kg dw in sediments and below detectable limit to 2.11 mg/kg dw in fish samples. Mercury values ranged between .14 and .31 mg/kg dw in sediment samples and .12 and .35 mg/kg dw in fish samples. Cadmium was the only heavy metal concentration that was below the detection limit in the three matrices. Significant differences were observed for some heavy metal concentrations in water, sediments and fish across sites (p < .05). The levels of lead and chromium in fish were above the East African Standard, World Health Organization and European Union limits. The results of the present study recommend a possible reclassification of the lake, an immediate ban on fish harvesting and consumption from Lake Nakuru and a policy intervention on the fishery and pollution management.

HEAVY METAL CONTAMINATION IN BOTTOM SEDIMENTS OF FIVE LARGE LAKES OF RAIPUR, CHHATTISGARH, INDIA

Entry of heavy metals into aquatic environments generally takes place due to human activities like agriculture, combustion, industrial plants, sewage and settlements. Once entered into the aquatic system the heavy metals from different sources pose risk to the aquatic ecosystem. Therefore, a detailed investigation of heavy metals (Mn, Fe, Zn, Cr, Ni, Cu, Pb, V, Co, As, Mo and Cd) concentration in the bottom sediments of five large Lakes of Raipur was carried out. The data were interpreted in terms of Geoaccumulation Index (Igeo), Enrichment factor (EF), Contamination Factor (CF), Pollution Load Index (PLI) and Modified Degree of Contamination (mCd). The study indicates that the degree of heavy metal contamination in the bottom sediments of the five large lakes of Raipur follow the order Maharaja Bandh Talab> Budha Talab > Sarju Bandh Talab > Bhaiya Taraiya Talab > Khokho Talab. Fe, Zn, Cr, Cu, Pb and Mn pose problems to the ecosystem of the Lakes. The contamination level of elements follow the order Zn>Fe>Cr>Mn>Pb. The high Fe, Cr, Cu, Zn, Pb concentrations in the sediments of Lakes are mainly caused by the use of pesticide and fertilizer in agricultural areas and runoff from settlements without sewage systems. The highly toxic heavy metals can have adverse impact on the aquatic organisms including fishes. This study warrants a detailed ecotoxicological investigation in the lakes followed by execution of Lake rejuvenation programme.

The current chemical composition of inland water bodies of the Volga-Akhtuba floodplain (Russia)

The problem of clean water is one of the most important environmental problems in the world. It is impossible to prevent the occurrence of adverse environmental situations without careful monitoring of the aquatic ecosystems state. The assessment of the current chemical composition of the Volga-Akhtuba floodplain shallow channels (Peschanyj, Dudak, and Dudachenok) in the water-bottom sediments system was carried out. Studied shallow channels dried out during the summer-autumn lowwater period for the last few decades. Studies were carried out after the clearance and ecological rehabilitation of the shallow channels. It was found that almost all the studied indicators in water samples correspond to the established quality standards. There is uneven distribution of heavy metals in the studied shallow channels. It can be caused by the influence of hydrodynamic conditions, changes in water and sediment flow, as well as local factors, including the catchment heterogeneous geology. The analysis of the metals content in bottom sediments with permissible ones made it possible to detect excess for Hg (0.18?0.75 mg/kg), Cd (1?2.12 mg/kg), Mn (370.8?493.3 mg/kg), Ni (2.6?67.9 mg/kg), Pb (14.3?22 mg/kg), Zn (75.2?147 mg/kg). The content of As (1?1.4 mg/kg) and Cu (8.54?28.7 mg/kg) in bottom sediments does not exceed the permissible concentrations. The obtained results will form the basis for a general comprehensive assessment of the clearance and ecological rehabilitation of the Volga-Akhtuba floodplain watercourses. It is necessary to continue monitoring the watercourses state and strengthen efforts to preserve the resilient ecosystem of the Volga-Akhtuba floodplain.

Metal pollution status and health risk assessment of beach sediments along the Mersin coast, Turkey

In the present study, the ecological risk assessment of metal contamination in beach sediments along the Mersin coast was determined using the metal contents of beach sediments in Mersin, Kızkalesi, Susanoğlu and Taşucu region obtained between 2006 and 2009. Furthermore, the potential health risk assessment for ingestion and dermal contact pathways of adults and children was determined. Ecological risk assessment of heavy metals showed that there is no pollution in the beach sediments for the metals Cu, Pb and Zn for the all studied coasts. However, the high ecological risk indices calculated in this study strongly suggested an apparent Cd, Cr and Ni pollution in the studied beach sediments due to natural and anthropogenic contamination. Study findings indicated the HI values were greater than 1 for the metal Cr. The TCR values were higher than 1.00E-04 for the metals Cr and Ni calculated for adults, and for the metal Cu, Cr and Ni calculated for children, respectively. All these findings showed that there is a high carcinogenic risk for adults and children resident in the Mersin province from carcinogenic Cr and Ni whilst the studied coasts have additional health risks to children from carcinogenic Cu.

THE RELATIONSHIP OF MACROZOOBENTHOS ABUNDANCE WITH OIL AND METAL CONCENTRATIONS IN SEDIMENTS AROUND COASTAL WATERS INDUSTRIAL AREA OIL CITY OF DUMAI RIAU

Some studies say the pollution level in the waters oil industry in Dumai City, Riau. The level of pollution that occurs will affect the abundance of macrozoobenthos. This research aims to know the concentration of oil and heavy metals in sediments in the waters around the area of the Dumai City oil industry, knowing the effect of oil on the abundance of macrozoobenthos. This research method includes placement of research stations, observation and sampling, TSS sample analysis method, concentration oil in sediment samples, heavy metal concentrations of Pb, Cd, and Cu at sediment samples, macrozoobenthos abundance Analysis, and data analysis. Results Research Average concentration of oil in sediments in water areas The oil industry of Dumai City, Riau, has passed the threshold that has been set determined by the Department of Water Resources Quality Assurance/Quality Control Program That is > 1000 ppm, so it can be said that station 1 up to 9 are polluted and harmful to organisms that live on the bottom those waters relationship of oil concentration, heavy metals (Pb, Cd, and Cu) moderate to weak

Техногенные шахтные воды Восточного Донбасса и их влияние на микроэлементный состав речных вод и донных отложений

The article presents the results of studies of the technogenic mine waters (TMW) effect on small river waters and sediments within Eastern Donbass. A set of typomorphic trace elements (Fe, Mn, Li, Sr) was identified in the chemical composition of TMW that reflects the regional specificity of the technogenic process of their formation. The behavior features of iron and manganese in the zone of TMW outflows appears in their rapid precipitation from the water column, and the most part of them (more than 95 % of Fe and 82 % of Mn) are deposited up to the first 500 m downstream. Meanwhile the process of lithium and strontium precipitation requires a longer period resulting in the formation of extensive hydrochemical dispersion fluxes of these elements. The mass precipitation of iron from the water column in the 500-meter range of TMW exposure and its fixation, mainly in the form of stable magnetite, contributes to an increase in metal concentrations in bottom sediments within the impact zone. In the distribution of manganese, strontium and lithium, the grain size distribution of river sediments, in particular, the amount of pelite fraction, plays a significant role, and therefore, under certain hydrological conditions, they can be actively involved in mechanical migration, forming longer lithogeochemical scattering flows in comparison with iron.

Predictions of heavy metal concentrations by physiochemical water quality parameters in coastal areas of Yangtze river estuary

Due to the degradation-resistant and strong toxicity, heavy metals pose a serious threat to the safety of water environment and aquatic ecology. Rapid acquisition and prediction of heavy metal concentrations are of paramount importance for water resource management and environmental preservation. In this study, heavy metal concentrations (Cr, Ni, Cu, Pb, Zn, Cd) and physicochemical parameters of water quality including Temperature (Temp), pH, Oxygen redox potential (ORP), Dissolved oxygen (DO), Electrical conductivity (EC), Electrical resistivity (RES), Total dissolved solids (TDS), Salinity (SAL), Cyanobacteria (BGA-PE), and turbidity (NTU) were measured at seven stations in the Yangtze river estuary. Principal Component Analysis (PCA) and Spearman correlation analysis were employed to analyze the main factors and sources of heavy metals. Results of PCA revealed that the main sources of Cr, Ni, Zn, and Cd were steel industry wastewater, domestic and industrial sewage, whereas shipping and vessel emissions were typically considered sources of Pb and Cu. Spearman correlation analysis identified Temp, pH, ORP, EC, RES, TDS, and SAL as the key physicochemical parameters of water quality, exhibiting the strongest correlation with heavy metal concentrations in sediment and water samples. Based on these results, multiple linear regression as well as non-linear models (SVM and RF) were constructed for predicting heavy metal concentrations. The results showed that the results of the nonlinear model were more suitable for predicting the concentrations of most heavy metals than the linear model, with average R values of the SVM test set and RF test set being 0.83 and 0.90. The RF model showed better applicability for simulating the concentration of heavy metals along the Yangtze river estuary. It was demonstrated that non-linear research methods provided efficient and accurate predictions of heavy metal concentrations in a simple and rapid manner, thereby offering decision-making support for watershed managers.

Health Risks Associated with the Concentration of Heavy Metals in Sediment, Water, and Carp Reared in Treated Wastewater from a Slaughterhouse

The use of purified slaughterhouse wastewater in carp ponds, and the use of wastewater from the pond for the irrigation of agricultural fields, was the basis for the construction of an integrated system of agricultural production as a sustainable solution for the food and fish production industries. The negative side of such integrated production systems is the concern related to the safety of fish meat produced in such a system. The aim of this research was to determine the concentration of heavy metals and metalloids in the wastewater from the slaughterhouse, in the pond water and sediment, in the carp tissue and in the water leaving the pond, and to evaluate the effectiveness of the integrated system and the safety of the produced fish. Sampling was carried out in spring and autumn. The mean concentrations in all water samples (µg/L) were: As (12–125), Cd (0.12–4.2), Hg (1.14–14.21), Pb (<0.1–17.2), Cu (<0.1–44.6), Fe (17.02–425.2) and Zn (2.91–186.2), with the highest numbers in the wastewater, where it was above the prescribed limit values for the wastewater discharged from the slaughterhouses into natural recipients in both samplings. The efficiency of the wastewater treatment plant for heavy metals and metalloids was very high, in the range of 87% to 98%. The water from the pond corresponded to class 3 in terms of the concentration of heavy metals and metalloids both in spring and autumn, and can be used freely for breeding cyprinid fish species. The water from the irrigation canal corresponded to class 2/3 and can be used for irrigation. The mean concentrations of heavy metals and metalloids in the sediments (mg/kg) were: As (3.00–4.88), Cd (0.16–0.96), Hg (0.21–1.47), Pb (0.77–2.29), Cu (49.60–60.90), Fe (3.94–5.32) and Zn (92.8–115.20). The content of heavy metals in different organs of carp differed significantly depending on the season. The trend of heavy metal accumulation in common carp muscles in spring was: Zn > Fe > Cu > Pb > Hg > Cd > As, and in autumn: Zn > Fe > Cu > Pb > As > Cd > Hg. Metal concentrations in the examined fish samples were far below the WHO guidelines. It can be concluded that carp produced in a pond supplied with purified wastewater from the slaughterhouse industry, in terms of the concentration of residues of the tested heavy metals and metalloids, is safe for human consumption.

Total and Bioaccesible Metal Concentrations in Surficial Sediment Affected by a Mining Spill: Case of Sonora River, Northwest of Mexico

ABSTRACT Metals and metalloids are persistent contaminants that are associated with many anthropogenic activities and mining in particular. On August 6, 2014, approximately 40,000 m3 of toxic acid mining waste was spilled from the Buena Vista del Cobre Copper Mine. The spill affected 220 km of the Sonora River Basin (SRB) over a surface area of ~ 30,000 km2. This study evaluated the total and bioaccessible concentrations of six metals and their enrichment in surficial sediments in spill and no-spill sites in the SRB. All metal concentrations showed significant seasonal and spatial variation (p < .05) in surficial sediments, with a general distribution of Al > Fe > Mn > Zn > Cu > Pb. The total and bioaccessible concentrations of the elements in this study were similar between spill and no-spill sites. Variations in element levels were associated with re-suspension and advection related with rain run-off, and the element concentrations were associated with the high natural concentrations in surficial sediments found throughout the SRB (considering the predominant soil types). The enrichment factor (EF) indicated minor to moderate-severe enrichment of Fe and Mn, minor to severe enrichment of Pb and Zn, and moderate-severe to very severe enrichment of Cu. The bioaccessible percentages of metals with respect to the total concentrations varied from 0.23 to 69.9%. The Sediment Quality Guidelines criteria indicated that adverse effects on biota that are mainly due to Cu levels are potentially present. Chronic exposure to metals may produce intermediate and long-term effects on the metabolic responses of biota.

Heavy Metals Assessment and Health Risk to Consumers of Two Commercial Fish Species from Polyculture Fishponds in El-Sharkia and Kafr El-Sheikh, Egypt: Physiological and Biochemical Study

Metal pollution is a major environmental concern worldwide, especially in Egypt. The aquaculture industry uses widespread artificial feeds to stimulate fish production, leading to metal accumulation in the aquatic environment. Heavy metal concentrations (HMCs) in sediments, water, and tissues were studied to study the effect of pollution levels on heamatological, and biochemical, immunological aspects of farmed fish as well as on human health. Results declared that the HMC levels in the water and sediment were significantly different between El-Sharkia and Kafr El-Sheikh fishponds (T-test, p < 0.05). This was supported by the metal pollution index in the water and sediment, indicating that El-Sharkia fishponds (ES fishponds) were more contaminated than Kafr El-Sheikh fishponds (KES fishponds). Also, HMCs in fish tissues were significantly increased in fish cultivated in ES fishponds than in KES fishponds. Haematological, immunological, and biochemical alterations of Bolti (Oreochromis niloticus) and Topara (Chelon ramada) fish were significantly different within the different fish species as well as the different fishponds. From the human health perspective, the THQ-HMC and HI-HMC associated with the consumption of muscle suggest a safe non-carcinogenic risk to human health. In contrast, cadmium poses a cancer risk to children who consume the muscular tissue of Bolti fish from ES fishponds, which should be regarded as a warning sign based on data indices and a human health perspective. In order to minimise HMC pollution in the aquaculture sector, it is advisable to take possible assessments and carry out continuous monitoring considering international WHO/FAO assessments.

Water and Sediment Chemistry as Drivers of Macroinvertebrates and Fish Assemblages in Littoral Zones of Subtropical Reservoirs

Reservoirs are human-made ecosystems with diverse purposes that benefit humans both directly and indirectly. They however cause changes in geomorphological processes such as sediment cycling and influence the composition and structure of aquatic biota. This study aimed to identify water and sediment quality parameters as drivers of macroinvertebrates and fish communities during the cool-dry and hot-wet seasons in the littoral zones of three subtropical reservoirs (Albasini, Thathe and Nandoni). Macroinvertebrates and fish were collected from three sites (n = 3 from each site) in each reservoir. A total of 501 and 359 macroinvertebrates and fish individuals were collected throughout the sampling period, respectively. The present study employed a two-way ANOVA in conjunction with redundancy analysis (RDA) to assess the relationships that exist between water and sediment variables, macroinvertebrates diversity and species abundances across seasons. Based on the two-way ANOVA model, significant differences were observed across reservoirs for evenness, Simpson’s diversity, and total abundance, while seasonal differences were observed for most metrics, with exception for evenness. The RDA results identified four water variables (i.e., water temperature, oxidation–reduction potential, pH and conductivity) and one sediment metal (Mg) as the most important parameters in driving the fish community structure. Field observations and metal results attest that the Nandoni reservoir shows high concentrations of metals in sediments as compared to other reservoirs, suggesting that anthropogenic activities such as car washing, brick making, recreation, fishing, wastewater treatment work and landfill site may be the major contributor of metals to the Nandoni reservoir, which accumulate in the littoral zones. Findings of this study highlight the need to analyze reservoir ecological conditions at several scales. The study of macroinvertebrates and fish, water, and sediment chemistry in the littoral zone laid the groundwork for proposing measures for conserving aquatic ecosystems.

Toxic metals in cyanobacterial mat of Big Lachman Lake, James Ross Island, Antarctica.

The northern part of James Ross Island is the largest deglaciated area in the Antarctic Peninsula region with a unique ecosystem created during the Late Glacial. This research aims to evaluate the degree of contamination of the locality with toxic metals (As, Hg, Cd, and Pb) through bioindicators in the aquatic environment-colonies of cyanobacteria and algae. For this purpose, bottom lake sediments of Big Lachman Lake were studied for contents of Fe, As, Hg, Cd, Pb, Cr, Co, Ni, Cu, and Zn, as well as samples of cyanobacterial mat, in which Fe, As, Hg, Cd, and Pb were determined. Metal contents were determined by means of inductively coupled plasma optical emission spectrometry and atomic absorption spectrometry. The contents of metals in sediments did not differ from the usual values in the area of the Antarctic Peninsula. The bioaccumulation of metals in cyanobacterial mat was evaluated by calculating enrichment factors (the calculation to Fe as a reference element). According to this method, moderate pollution of Big Lachman Lake was confirmed for Hg and Cd.

Heavy metal concentrations in surface waters of Hurghada and environs, Red Sea Coast, Egypt, and their correlation with sediment distribution

This study investigates the properties and chemistry of surface water in Hurghada and its adjacent areas, with a focus on assessing the potential impact of human activities on water quality by measuring the concentrations of heavy metals in surface water samples. A total of fifty-nine surface water samples were collected and analyzed for various heavy metals, including manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg), and lead (Pb) using the AAS technique.The results indicate that at the Desert Rose Resort transect, the average total concentrations of heavy metals were within the following ranges: Fe (average of 26.96 μg/L), Cu (average of 0.61 μg/L), Zn (average of 6.31 μg/L), and Pb (average of 0.75 μg/L). Conversely, at the Abu-Shaar transect, Ni (0.87 μg/L) and Cd (average of 0.02 μg/L) were the dominant heavy metals, while Mn exhibited the highest mean value (1.80 μg/L) at the El-Samaka Village transect. Notably, Hg was not detected in any of the samples within the study areas.Comparative analysis of heavy metal concentrations in Hurghada's surface waters with data from the Red Sea coast and other global regions reveals that the study areas maintain heavy metal concentrations well below the maximum permissible values for the marine environment. These findings suggest that human activities have not significantly impacted heavy metal levels in the region's surface waters.Additionally, statistical assessments, such as correlation coefficients (r), were employed to explore the relationships between heavy metal concentrations in water and sediment. These relationships provide valuable insights into the dynamic balance of elements within the sediment and their potential direct or indirect transfer into the water.

Seasonal variability in trace metal concentrations in sediment samples from the Puducherry and Cuddalore coasts of Tamil Nadu, India

The Puducherry-Cuddalore coastal region was chosen for research because these two cities receive the majority of their anthropogenic inputs from the Ponnaiyar and Gadilam rivers, which supply domestic, industrial, fishing port, and agricultural inputs. In southern Tamil Nadu, the Ponnaiyar and Gadilam rivers, as well as other minor rivers, combine and discharge into the southeastern Indian Ocean. Some studies have been carried out to investigate the impact of anthropogenic, industrial, and other influences on surface sediment samples along Tamil Nadu's south-east coast, from Puducherry to Cuddalore. A detailed assessment of these findings is explained in this research. Geochemistry and geology, as well as alterations in sediments, have all been widely researched. Heavy metals were absorbed by alluvial sands, silts, clays, and organic matter, which is also an indication of pollution in the environment. As a result, the metal content in pre-monsoon sediments is lower in Puducherry coastal areas than in Cuddalore coastal areas. Because of a rise in clay composition, higher trace metals were detected in post-monsoon sediments than in pre-monsoon sediments. Contamination levels in Puducherry and Cuddalore coastal areas were moderate to high in post-monsoon than pre-monsoon periods, with the exception of Cr, which significantly above the range of widespread pollution in post-monsoon periods. Sediments sampled from Puducherry and Cuddalore offshore were found to have moderate to considerable contamination. With the notable exception of lead, most elements of trace metal levels in sediments indicate relatively low levels of pollution. Among the consequences discussed in the report's findings are alterations in post-monsoon hydrodynamic processes and environmental health of the marine ecosystem.

Distribution and Concentration of Pb, Cd, and Hg Metals Due to Land Use Influence on Sediment in Malili River, East Luwu Regency

This research was conducted in the waters of Malili River, East Luwu Regency, with 4 observation points in Malili River East Luwu Regency, namely: (a) Southeast Sulawesi Sub Das (Point 1) namely Pongkeru village bridge, Coordinate point 12126.69’8°” E; (b) Larona Sub Das Karebbe basin bridge (Point 2), Coordinate point 12115.09’9°” E; (c) The meeting point of Larona sub-dash and Pongkeru sub-dash (Point 3), coordinate point 12159.64’8°” E; (d) Upper Malili River, Malili village, Malili bridge (Point 4), Coordinate point 12147.20’5°” E. Metal concentration and distribution were analyzed descriptively with the help of images (maps), graphs, and tables. Differences in Pb, Cd, and Hg metal concentrations in sediments between point locations were tested using analysis of variance (ANOVA) through the SPSS version 22 program. The relation between grain size, organic matter, and Pb, Cd, and Hg metal concentrations was tested using linear correlation. The results showed that the sediment content of Pb and Cd metal concentrations at each point location did not exceed NOAA (1999) quality standards. In the sediment, Hg metal concentration exceeds the quality standards of NOAA (1999) at each point, namely point 1. Pongkeru 0.590 μg.g-1, point 2. Karebbe 0.229 μg.g-1, point 3. Kawasule 0.514 μg.g-1 and point 4. Malili 0.358 μg.g-1. The relation between sediment size and Pb, Cd, and Hg metal concentrations at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment. It may be due to other factors, such as the source of heavy metal pollutants in each different point location. The relation between organic matter and the concentration of Pb, Cd, and Hg metals at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment because it may be due to other factors, such as different sources of heavy metal pollutants in each point location.

Assessment of some heavy metal content in sediments of a mangrove swamp, niger delta, nigeria using applicable ecological risk indices

Sediments can act as pollutant sinks and a source of pollution in aquatic environments. The surface sediments of the Isaka–Bundu tidal swamp, Niger Delta was assessed for heavy metal content using standard methods and assessment indices. The study was carried out in three stations between January and June 2022. Five heavy metals (lead, copper, cadmium, nickel and zinc) were evaluated while eight assessment indices (Contamination Factor - CF, degree of contamination - DC, Ecological Risk - Er, Potential Ecological Risk - PERI, Pollution Load Index - PLI, Enrichment Factor - EF, Geo-accumulation Index - Igeo and Quantification of Contamination -QoC) were applied. Results showed that cadmium and copper exceeded permissible limits while lead, zinc and nickel were within limits. Stations 1 and 3 recorded significantly higher values indicating anthropogenic influence. The dominant anthropogenic activities observed in the area include maritime and dockyard activities and artisanal crude oil refinery. The assessment indices showed that the sediments were at various levels of heavy metal pollution mainly influenced by copper and cadmium viz: CF: Cu (considerable degree) and Cd (very high degree), DC (very high degree), Er: Cd (high ecological risk) and Cu (very high ecological risk), PERI (significant high ecological risk), PLI (very high level pollution), EF: Pb, Zn, Cu (Station 1) and all Cd (extremely high enrichment), Igeo: Cd (extremely polluted) and QoC: Cu and Cd (anthropogenic source). The sediments were highly polluted with toxic metals, which is detrimental to humans and aquatic biota.Keywords: Heavy metal; Indices; Mangrove; Niger Delta; Sediment.

Comparison of leaching behaviour of heavy metals from sediments sampled in sewer systems - environmental and public health aspect.

The article analyzes the content of heavy metals and standard physical as well as chemical pollution indicators in different types of sediments from stormwater, combined sewer and sanitary sewer systems. Nickel, lead, chromium, copper, zinc and cadmium, as well as standard physical and chemical pollution indicators, were determined in sewage sediments. Aqueous extracts of sediments samples, taken from storm water sewer inlet sediments traps, storm sewers, sanitary sewers and combined sewers, were prepared in accordance with PN-EN 12457-2:2006. After mineralization, the concentrations of the metals: nickel, lead, chromium, copper, zinc and cadmium in the extracts were determined using the inductively coupled plasma emission spectroscopy technique. The results were analyzed with a non-metric multidimensional scaling algorithm. The heavy metal content was variable depending on the sediments collection site. The heavy metals nickel, lead, chromium, copper, zinc and cadmium were found in the sediments from stormwater inlets, storm sewer and sanitary sewer channels, with variability in the concentration of individual metals. The sediments from the flushing of sanitary sewers and combined sewers did not contain cadmium. The content of heavy metals in sediments varied depending on the sampling location and type of sewer system, indicating the need for detailed monitoring to identify the sources of emissions. Sediments from stormwater sewers have higher concentrations of heavy metals, with those from sewer inlets showing zinc concentrations exceeding regulatory limits, highlighting the variability and potential environmental impact of different sewer systems.

Assessment of heavy metal content and ecological risk in offshore surface sediments of the Northern Persian Gulf: Implications for environmental management

Offshore surface sediment samples from fifty-five stations in the northern parts of the Persian Gulf and the Strait of Hormuz were examined to evaluate the content and ecological risk of heavy metals. The physicochemical characteristics of both surface water and deep water were measured using probes and CTD. To determine the source of pollution and assess the ecological risk, various indicators were used, including contamination factor (CF), contamination degree (CD), enrichment factor (EF), pollution load index (PLI), and risk index (RI). The average concentrations of heavy metals in sediment samples were Fe: 1.4 (0.2–2.7%), Cr: 72.9 (8−127), Ni: 59.8 (14−113), V: 43.4 (7−77), Zn: 35.7 (3−58), Cu: 17.5 (2−29), Pb: 12.1 (5−48), Co: 9.4 (1−17), As: 3.9 (1.7–7.2) ppm. Ni and Cr concentrations in almost all Persian Gulf stations especially in shallower parts were higher than their threshold effect level, while Pb, As, Zn, and Cu concentrations were below the threshold values in all stations. The results revealed that EF for all investigated metals in all stations was less than 1.5, which indicates that the studied region had low enrichment and the origin of the heavy metals is natural. However, human activities have contributed to Ni enrichment in the Jask and Bandar Abbas coasts. CD values varied between 11.7 and 14.6, exhibiting the range of moderate pollution to lowest possible pollution category. The PLI for all samples was in the range of 1.2–2.2, which demonstrates advanced pollution load. RI (=∑Eij) varied between 34 and 89, indicating a low ecological risk (IR<110).