Heavy Metals In Sediment Samples Research Articles

Using Bottom Marine Sediments as Environmental Indicator State of (Tolmaitha – Toukra) Region at Eastern North Coast of Libya

This study was carried out on sediment samples collected from the region extended between Tolmaitha and Toukra towns at (Libya) North eastern coast. The study aimed to use the marine sediment as indicator pollution of the studied area. Different heavy metals of (Fe‚ Mn‚ Zn‚ Cu‚ pb‚ Cd‚ Co and Cr) beside the organic matter (O.M)‚ Total phosphorus (T.P) and total nitrogen (T.N) were determined. The results showed variations in concentrations of total phosphorus (T.P) contents and ranged between (0.0037-0.319 ppm) and (0.007-0.240 ppm) during winter and summer seasons‚ respectively. The total nitrogen contents were fluctuated in the ranges of (0.0017-0.370 ppm) and (0.014 – 710ppm) during winter and summer seasons‚ respectively. Also the results showed that the organic matter (O.M) values were ranged between (0.072-0.720%) and (0.097-0.502%) during winter and summer seasons‚ respectively. The contents of heavy metals in sediment samples during summer season were ranged as follows:(16.5 – 398.1 µg/g)¸ (10.436 – 33.879 µg/g)¸ (13.8 – 287.6 µg/g)¸ (0.78 – 31.56 µg/g)¸ (1.34 – 46.72 µg/g)¸ (2.36 – 128.76 µg/g)¸ (9.15 – 28.16 µg/g)¸ (2.17 – 323.41 µg/g) ¸ for Fe¸ Mn¸ Zn¸ Cu¸ Pb¸ Cd¸ Co¸ and Cr¸ respectively. The results showed high values of calcium in the studied sediment samples compared to the potassium and sodium contents. The results of the studied gave indication that area under investigated contain high values of heavy metals, total phosphorus and total nitrogen, this is mainly attribute to the human activities at the studied locations.

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).

Heavy Metal Pollution in a Lake: An Assessment of the Ecological Threat

The purpose of this study was to investigate and evaluate the presence of different heavy metals in sediment samples collected from water of Durgam Cheruvu . The concentrations of six heavy metals, namely arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn), were quantified using the technique of inductively coupled plasma-atomic emission spectroscopy (ICPAES). The investigation employed relative enrichment factors and prospective ecological risk indices to examine the contamination levels of heavy metals in sediment samples and evaluate their potential ecological impact on the surrounding ecosystem. The order of heavy metal sediment enrichment factors was determined to be as follows: chromium (Cr) exhibited the highest enrichment factor, followed by arsenic (As), cadmium (Cd), zinc (Zn), copper (Cu), and lead (Pb). Several potential ecological risk indices for heavy metals were identified. The order of decreasing reactivity of the elements is as follows: Cadmium (Cd) &gt; Arsenic (As) &gt; Chromium (Cr) &gt; Copper (Cu) &gt; Lead (Pb) &gt; Zinc (Zn). The prospective ecological risk indices, as determined through calculations, indicate that the lake has been low contaminated by heavy metals. Cadmium (Cd) exhibited a moderate level of potential ecological risk within the ecological environment and emerged as the primary factor contributing to the possible toxicity response indices associated with different heavy metals in Durgam cheruvu. The application of analysis of variance was employed to determine the statistical significance of the observed fluctuations in heavy metal concentrations. The analysis of mean seasonal concentrations of metals revealed statistically significant variations across different seasons and sampling sites. The pollution in Durgam Cheruvu may be attributed to industrial and anthropogenic activity. We have put up a series of techniques that can be implemented to mitigate the accumulation of heavy metals in the lake.

Risk Assessment of Heavy Metals in Sediment Samples from the Mae Chaem River, Chiang Mai, Thailand.

Heavy metals are significant environmental pollutants that are recognized as posing a potential health hazard to human beings. We investigated the concentrations of the heavy metals As, Cd, Cr, Cu, Ni, Pb, and Zn in surface sediments collected from the Mae Chaem River in Chiang Mai, Thailand, during the dry season in 2021. The mean concentrations of heavy metals in sediments were, in decreasing order, Zn > Cr > As > Pb > Ni > Cu > Cd. The mean values of As, Cd, Cr, and Cu were determined to be 32.5 ± 18.3, 0.33 ± 0.07, 45.8 ± 11.9, and 21.9 ± 7.42 mg Kg-1, respectively. These levels are higher than their standard levels in Thailand, namely 10.0, 0.16, 45.5, and 21.5 mg Kg-1, respectively. Principal component analysis (PCA) revealed that the primary origins of heavy metal contamination are predominantly attributed to residential settlements and agricultural areas. The hazard quotient (HQ) was used to estimate the non-carcinogenic risk of exposure to heavy-metal-bound surface sediments for both children and adults. The results showed that the HQ values for both groups were less than 1.0 (HQ < 1.0), indicating no risk. Moreover, assessment of the long-term risk for ingestion of toxic metals indicated no risk (<10-6) based on the lifetime cancer risk (LCR). However, the LCR values of As and Cr were 5.3 × 10-6 and 2.5 × 10-6, respectively, demonstrating the most elevated LCR among the hazardous metals in terms of children's exposure. Therefore, it is possible that children living in agricultural areas and participating in activities around the study area may be exposed to elevated concentrations of As and Cr.

Evaluation of the Effects of Heavy Metals on Sediments and Rainwater Samples Due to Gas Flaring in the South Eastern Nigeria

This study evaluates the concentrations of heavy metals in sediment and rainwater samples of Ibeno, south eastern Nigeria due to gas flaring. Surface sediment samples were collected randomly in six different sites during the dry season in the intertidal zone at extremely low tide from the flare point to a distance of about 250m away from the flare site. Rainwater samples were collected with the use of pre-clean basins at an open space in three selected communities of Ibeno and were transferred into different sterilized plastic rubbers with their labels. These samples were transported to the laboratory for analysis of heavy metals concentrations using a particle induced x-ray emission (PIXE) technique. Heavy metals such as Titanium (Ti), Chromium (Cr), Manganese (Mn), Iron (Fe), Copper (Cu), Zinc (Zn), Rubidium (Rb), Strontium (Sr), Zirconium (Zr) and Lead (Pb) were analyzed in sediments while Vanadium (V), Arsenic (As), Nickel (Ni), Lead (Pb), Iron (Fe), Copper (Cu), Zinc (Zn), Chromium (Cr), Manganese (Mn) and Cadmium (Cd) were obtained in rainwater. The concentrations of Iron (Fe) in sediments are higher at the study area than every other elements but Manganese (Mn) poses more negative effects than others. The four pollution indices such as enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF) and pollution load index (PLI) were employed to assess the contamination status of heavy metals in sediment samples of the study area. The results revealed the elemental trend to be in descending order in each area of this study, which followed the sequence Mn&gt; Zn&gt; Pb&gt; Cu&gt; Fe&gt; Sr&gt; Rb&gt; Cr&gt; Ti &gt;Zr, while PLI revealed the extent of pollution in each site which ranged from 1.44 to 1.94. Most of the heavy metals concentrations in sediments such as Mn, Zn, Pb, Cu and Fe were far above the permissible limits, while in rainwater samples Pb, Cd, Ni, Fe and Mn were far above the permissible limits by WHO, 2008 and NSDWQ, 2007. This revealed that the rainwater in the study area were not free from toxicity and are unfit for drinking. Analysis of multi-variant statistics such as Pearson’s correlation coefficient and cluster analysis were also applied to ascertain the relationship and sources of investigated heavy metals. Both positive and negative correlations were observed among some heavy metals at 0.01 and 0.05 levels, while the cluster analysis revealed four main clusters. The study revealed that the ecosystems in the studied areas were vulnerable to bioaccumulation of heavy metals in that soil which could be of hazard effect to the ecosystem.

Assessment of Heavy Metal Contamination in Beach Sediments of Eastern St. Martin’s Island, Bangladesh: Implications for Environmental and Human Health Risks

Heavy metal pollution in marine ecosystems is an escalating environmental concern, largely driven by anthropogenic activities, and poses potential threats to ecological health and human well-being. This study embarked on a comprehensive investigation into the concentrations of heavy metals in sediment samples and evaluated their potential ecological and health risks with a focus on Eastern St. Martin’s Island (SMI), Bangladesh. Sediment samples were meticulously collected from 12 distinct sites around the island, and the concentrations of heavy metals, including Mn, Fe, Ni, Zn, Cr, Pb, and Cu, were quantified utilizing atomic absorption spectrometry (AAS). The results revealed that the average concentrations of the metals, in descending order, were Mn (269.5 ± 33.0 mg/kg), Fe (143.8 ± 21.7 mg/kg), Ni (29.6 ± 44.0 mg/kg), Zn (27.2 ± 4.34 mg/kg), Cr (8.09 ± 1.67 mg/kg), Pb (5.88 ± 0.45 mg/kg), and Cu (3.76 ± 0.60 mg/kg). Intriguingly, the concentrations of all the measured metals were found to be within permissible limits and comparatively lower than those documented in various national and international contexts. The ecological risk assessment, based on multiple sediment quality indices such as the geoaccumulation index, contamination factor, and pollution load index, indicated a moderate risk to the aquatic ecosystem but no significant adverse impact on sediment quality. Additionally, the human health risk assessment, encompassing non-carcinogenic hazard indices for different age groups, was considerably below the threshold, signifying no immediate health risk. The total carcinogenic risk was also found to be below acceptable levels. These findings underscore the current state of heavy metal pollution in Eastern St. Martin’s Island, providing valuable insights for environmental monitoring and management. While the immediate risks were not alarming, the study highlights the imperative need for sustained monitoring and the implementation of rigorous regulations to curb heavy metal pollution in order to safeguard both ecological and human health. This warrants the development of policies that are both adaptive and preemptive to ensure the sustainable utilization and conservation of marine resources.

HEAVY METALS CONCENTRATION IN SEDIMENTS AND BIOACCUMULATIONS IN CATFISH (SILURIFORMES) AND TOMATO FRUIT (LYCOPERSIUM ESCALENTUM) FROM UNRECLAIMED MINING PITS

The study examined the levels of selected heavy metal in sediments and their bioaccumulation in catfish (Oreochromis niloticus) and Tomatos (Lycopersium escalentum) from selected unreclaimed mining pits used for irrigation and fish farming in Bukuru town, Jos south Local Government Area “L.G.A” Plateau State. Five (5) unreclaimed ponds were purposively selected; sediment, fish and tomato samples were collected from January to September, with January to March representing dry season and April to September as rainy season. Thirty-two (32) water samples were collected across the study area, while six (6) samples of fish and tomato were collected, three (3) for each season in addition to two controls sampled for different seasons. Samples were analyzed for Cd, Mn, Hg, Cu, Ni, Pb, Ur and Zn. All the heavy metal parameters except Zn, exceeded levels observed at control point as well as maximum permissible limits in the rainy season. Comparison of mean seasonal levels of heavy metals in sediment samples with control, revealed statistical difference at ρ &lt; 0.05, d = 0.007. Similar pattern was observed for the dry season at ρ &gt; 0.05, d = 0.008, an indication that the level of heavy metals presence in sediment samples from unreclaimed mining pits is statistically higher than levels at control point, irrespective of season. Similar results were obtained for Catfish in both seasons (ρ &lt; 0.05, d = 0.006 and ρ &lt; 0.05, d = 0.02) and Tomatoes (ρ &lt; 0.05, d = 0.003 and ρ &lt; 0.05, d = 0.04). These sites should be urgently reclaimed using approved reclamation techniques to eradicate the adverse health impact of consumption of the fruits, animal protein and vegetables cultivated at the sites.

Ecological risks of some heavy metals in sediment samples collected from downstream of the Red river

This study aimed to assess the accumulation of some heavy metals such as Cu, Pb, Cd, and Cr in the sediments collected from downstream of the Red river from the south of Hanoi city to Nam Truc district, Nam Dinh province. Besides, the geological accumulation index (Igeo) and the potential ecological risk index were calculated to understand the impact of heavy metal content in the sediments on the ecosystem. The results showed that the concentration of several metals (Cu, Pb, Cd, Cr) in 20 sediment samples was lower than the permitted values specified in Technical Regulations on sediment quality (QCVN 43:2017/BTNMT). However, according to the Canadian guidelines, the concentrations of metals in 50% of samples had a low level of effect. The potential ecological risk index of metals ranges from 1.8 to 11.6, revealing that the study area has a low-level metal risk. This data can clarify the area’s potential risk level and provide the scientific basis for recommending measures to control and reduce sources of metal pollution into the aquatic environment.

Spatial distribution and pollution assessment of heavy metals in sediments from the Brahmaputra River watershed in Bangladesh.

Spatial distribution and pollution assessment of selected heavy metals such as barium (Ba), chromium (Cr), nickel (Ni), lead (Pb), vanadium (V), arsenic (As), zinc (Zn), and copper (Cu) in sediments of the Brahmaputra River watershed in Bangladesh was investigated. The mean abundances (ppm) of heavy metals in sediment samples were in decreasing order Ba (375.60) > V (67.60) > Cr (54.10) > Zn (48.20) > Ni (22.28) > Pb (20.25) > Cu (7.59) > As (4.21). Concentrations of Pb and As in the sediments are enriched relative to the average upper continental crust composition, while Ba, V, Cr, Zn, Ni, and Cu decrease considerably. A higher concentration of Pb and Ni indicates that Brahmaputra River watershed samples receive a significant contribution from anthropogenic sources of heavy metals. Chromium displays marked positive correlation with V (r = 0.91, p = < 0.01), inferring a similar source materials input into the watershed. The geo-accumulation index (Igeo) values suggest that the sediments were uncontaminated to moderately contaminated by Ni, Zn, Pb, V, and Cr, whereas moderate to heavily contaminated by As and Cu. The contamination factor (CF) confirmed that sediments in the watershed were moderate to highly contaminated by As, Cu, and Cr. The pollution load index (PLI) values for most of the samples were over one (> 1), indicating an advanced decline in the watershed sediment quality. The overall results of a multivariate statistical analysis suggest that Ba, V, Cr, and Zn contents were all-natural sources, and Pb, Ni, As, and Cu were derived from both natural and anthropogenic sources.

Assessment of heavy metal contamination in sediment at the newly established tannery industrial Estate in Bangladesh: A case study

This research work was focused to evaluate the concentration of heavy metals ( i.e. , Cr, Pb, Mn, Cu and Fe) in sediment samples collected from the Dhaleshwari River near the area of a newly established tannery industrial estate, Savar, Bangladesh. The heavy metals in sediment samples were ascertained by the atomic absorption spectrophotometer (AAS). This study revealed that the metal concentration for chromium (Cr), lead (Pb), manganese (Mn), copper (Cu) and iron (Fe) were found to be 14.8–748 (186 ± 241) mg/kg, 2.38–21.1 (8.78 ± 6.15) mg/kg, 1.59–6.29 (3.12 ± 1.38) mg/kg, 0.36–4.75 (1.76 ± 1.47) mg/kg and 3.87–154 (42.7 ± 49.1) mg/kg (dry wt) respectively. The concentration of heavy metals in sediment samples descends with the following order: Cr > Fe > Pb > Mn > Cu. Sediment contamination was assessed on the basis of geo-accumulation index ( I geo ), contamination factor ( CF ) and pollution load index ( PLI ). The average I geo values for Cr, Pb, Mn, Cu and Fe were found to be (−0.44 ± 1.87), (−2.18 ± 1.20), (−8.80 ± 0.63), (−5.80 ± 1.36) and (1.59 ± 1.87) respectively. The I geo values values of Cr and Fe for some sampling stations were found to be higher. The PLI value for all the sample stations (S1-S8) were 0.58, 0.66, 0.71, 0.69, 0.88, 0.86, 0.83 and 0.83 correspondingly. The CF values for Cr and Fe in some stations was observed at moderate, considerate and high contamination level. The spatial distribution of heavy metals in the study area was presented by interpolation technique. The results of spatial distribution pattern showed that the high concentrated zones of Cr was found at the dumping zone (~S5) of the leather industrial city. On the other hand, the spatial distribution pattern for the studied metals (Pb, Mn, Cu and Fe) showed that the maximum metals concentrations were found in the southeastern part, which was nearby effluent dumping zone. The ecological risk assessment in sediment samples revealed that there is no significant risk observed by the metal( oid )s at this moment. Considering Cr concentration, the modified hazard quotient ( mHQ ) showed that about 75% of the samples were low to severely polluted by Cr, while 25% of the samples were extremely polluted by Cr as well as mHQ ≤ 3.5. Based on PMF analysis, two potential sources of heavy metals were identified in the study region: first, biochemical and leather tanning industries (Cr); second, the mixed effect of geogenic sources and atmospheric deposition and traffic emission (Fe and Pb). • The conc. for Cr, Pb, Mn, Cu and Fe in sediment samples were determined by AAS. • The concentration of heavy metals in sediment descends Cr > Fe > Pb > Mn > Cu • Spatial distribution pattern showed that the high Cr conc was found at the dumping zone • There is no significant ecological risk was observed by the metal( oid )s in the study area. • PMF analysis revealed two potential sources of heavy metals in the study region

Potential Ecological Impacts of Heavy Metals in Sediments of Industrially Contaminated Perennial Drain of India.

Globally, heavy metal contamination of natural waterways and surrounding environments due to anthropogenic activities has become a grave cause of concern. Therefore, the present study was conducted to analyze the ecological risk posed by heavy metals in sediment samples (N = 24) collected from different depths of Budha Nalah drain located in Ludhiana (Punjab, India). The concentration of As, Cd, Cr, Cu, Ni, Pb and Zn were found to be above the maximum permissible limits for metals in soils and sediments, which was attributed to anthropogenic activities (industrialization, urbanization and agriculture). The values observed for Contamination Factor, Enrichment Factor and Pollution Load Index revealed that sediment samples were highly contaminated by As, Cd, Cr and Pb. The ecological Risk Index (range: 212-1566) and Modified Risk Index (range: 2793-12,182) values indicated that high concentrations of metals (especially As, Cd, Cr and Pb) posed severe ecological risks in the areas around the drain.

Health risk assessment of heavy metals contamination in sediments of the River Nile, Damietta Branch using Mathematical Models

This study was conducted to evaluate heavy metals pollution in sediments of the Nile River- Damietta Branch using mathematical models of heavy metal indices (enrichment factor (EF), contamination factor (CF), pollution load index (PLI), degree of contamination (DC) and geo-accumulation index (Igeo)). The results showed that the concentrations of heavy metals in sediment samples, followed the order of Fe> Zn> Pb> Co> Ni> Cu> Mg. The EF for each heavy metal element was calculated relative to the background values after normalization with the Fe element. According to the mean values of EFs, the descending order of heavy metals enrichment in the sediments was: Cd >Fe> Pb > Co > Zn > Ni > Cu (greater to lower). Cd was considered to poses significant to very high enrichment along with the different stations along the study area. In addition, it recorded very high contamination (7.41±0.71) and Igeo mean value (6.50 ± 1.32) along the study area. PLI values varied between 0.813 and 2.331 along the study area with a mean value of 1.338 ± 0.477. This result showed a considerable degree of contamination (mean value =16.442 ± 7.136) along the branch. However, stations 3, 5, 9 and 10 recorded a very high degree of contamination with values (30.901, 33.867, 56.932 and 48.536), respectively. HI values of heavy metal order was: Cd (239.63) > Pb (72.65) > Co (34.732) > Ni (14.457) > Zn (5.952) > Cu (4.719) > Fe (2.896). With respect to human health, Ni, Pb, Cd, Fe, Zn, Cu, and Co were identified as potential contaminants. whereas, Pb, Cd and Cu are classified as non-carcinogenic by Agency for Toxic Substances and Disease Registry.

Temporal variations of heavy metals in sediment, soil and dust particulates across the rock quarrying districts of the Oban Massif, Southeastern Nigeria

Concentrations and distribution trends of selected heavy metals (Fe, Mn, Cu, Pb, Zn, Cd, Cr, Ni and As) in sediment samples, soil and dust particulates across the rock quarrying districts of the Precambrian basement Oban Massif, southeastern Nigeria were determined. The quarrying district was zoned into A comprises of quarries with operational histories of more than twenty years and B which were of younger age. Calculations from data sets gave information on metal enrichment factor, contamination factor, geo-accumulation index and pollution load index. Results revealed the trend: Fe > Mn > Zn > Ni > Cu > Pb > Cd > Cr > As in zone A and Fe > Mn > Zn > Ni > Cu > Cd > Cr > Pb > As for zone B. Contamination factors of heavy metals in samples across the two zones were generally low. Enrichment factor indicates mostly deficient to minimal enrichment. However a few localized samples indicate moderate, significant and extremely high enrichments in Pb, Zn and Ni. Pollution load index (PLI) of the heavy metals in sediment samples, soil and dust particulates from both zones indicates no pollution. Geo-accumulation index (Igeo) of metals across zones is largely of the unpolluted category. The observed values of heavy metal contamination in sediment, soil and dust particulates as well as their enrichment, PLI and Igeo were generally higher in the older than the younger quarrying zones of western Oban Massif.

Influence of watershed on the accumulation of heavy metals in sediments of urban rivers under tropical conditions: Case of N’djili and Lukaya rivers in Kinshasa Democratic Republic of the Congo

• Level of heavy metals in sediments from two river receiving systems was examined. • High concentration of Cr, Cu, Zn, As, Pb and Hg was observed in all studied sediments. • Correlation between parameters indicates the eventual common source of contamination. • High level of heavy metals can affect water quality and increase human health risks. The contamination of freshwater resource by heavy metals is still a major environmental and human health concern globally. The release of these contaminants into the aquatic environment can lead to the pollution of water resources and generate risks for aquatic living organisms and human health. The sediments can act as reservoir for heavy metals, thereby they are used to assess the pollution status of the rivers. In the present investigation, surface sediments collected from two urban rivers named, N’djili and Lukaya draining through the city of Kinshasa, Democratic Republic of the Congo were characterized for grain size, organic matter (OM) and heavy metals. Additionally, Sediment Quality Guidelines for the protection of aquatic life (SQGs), enrichment factor (EF) and geoaccumulation index (Igeo) were performed to determine the river pollution status. The results highlight high concentrations of heavy metals in sediment samples mainly from N’djili River, reaching the values (mg kg −1 ) of 180.3 (Cu), 451.5 (Zn), 185.8 (Pb) and 4.1 (Hg). These values exceed the SQGs. Based on EF and Igeo values, the sediments from the two rivers have severe enrichment and polluted with Cu, Zn and Pb, and moderate enrichment of Cr and As. In general, the positive correlation was observed between some heavy metals and OM suggesting that these contaminants could have originated from common sources with a similar transport pathway. Based on the SQGs, EF and Igeo, N’djili River is considered as highly polluted with heavy metals indicating environmental and human health potential risks. The results of this study clearly indicate that the pollution of urban rivers in developing countries can be explained by several anthropogenic activities such as urban runoff, uncontrolled landfills in riverbanks, untreated wastewater from densely populated areas, anarchic commercial and industrial settlements, and heavy road traffic. The approaches used in this study represent a useful tool to assess the river sediment quality of urban river which can be applied to similar environment.

Physicochemical Characterization of Mining Waste from the Betare-Oya Gold Area (East Cameroon) and an Adsorption Test by Sabga Smectite (North-West Cameroon).

This paper, firstly, characterizes the mining waste of the Betare-Oya gold area (East Cameroon). Surface waters are sampled and characterized physically (pH, electrical conductivity, turbidity, and suspended solids) and chemically by the determination of trace metals (Cu, Zn, Ni, Mn, Fe, Cr, As, and Pb). The concentrations of heavy metals in sediment samples are determined by X-ray Fluorescence Spectrometry (XRF) analysis. The statistical analysis tool is used to determine the existing correlation between the different physicochemical parameters. Secondly, an adsorption test for heavy metals determined is carried out on smectic clay of Sabga (North-West Cameroon) at ambient temperature. The results of physicochemical characterization of water samples reveal that waters of this gold mining zone are slightly acidic to neutral (6.3 pH < 7.1), mineralized (18.54 EC < 43 μs.cm−1), turbid (60 SS < 237.67 NTU), and polluted by suspended solids (50.5 < SS < 666.6 mg L−1).The determination of heavy metals in water samples shows that manganese, iron, arsenic, and lead concentrations are above the World Health Organization (WHO) limits. This indicates pollution. High concentrations of heavy metals as Cu, Ni, Mn, Fe, and Cr are observed in sediment samples. The correlation analysis indicates high correlations between turbidity and suspended solids; cadmium and lead in water samples; and copper and iron in sediment samples. The adsorption test reveals that the maximum percentage removal is 60, 89, 55, −89.74, and 100% for Cu, Zn, Mn, Fe, and Pb, respectively, after adding 0.5 g of Sabga smectic clay. This clay has a good potential adsorption of lead, zinc, manganese, and copper. However, the operating conditions favored desorption of iron.

Assessment of heavy metal pollution in coastal sediments of the western Caspian Sea.

The distribution of heavy metals in sediment samples from the western Caspian Sea coast (near industrial region, Sangachal Terminal) was investigated to obtain information about heavy metal pollution. Forty-three surface sediment samples were collected and analyzed for heavy metals (As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V, and Zn) using an Agilent 7700x inductively coupled plasma - mass spectrometer system. Hg concentrations were detected by cold vapor atomic absorption spectrometry using Varian SpectrAA 220FS + VGA-77 system. The average concentrations of these heavy metals at the same sampling locations followed the order of Fe > Mn > Ba > Zn > Cr > Ni > Cu > As > Pb > Co > Se > Mo > Cd > Hg. Single element pollution index values including geo-accumulation index (Igeo), contamination factor (Cf), and enrichment factor (Ef) were used to evaluate contamination with heavy metals in sediment samples. Three integrated indexes were used for assessing the degree of pollution: degree of contamination (DC), pollution load index (PLI), and ecological risk index (RI).

Determination of some Heavy metals in Sediment samples collected from Elabedia Traditional Gold Mining area – Sudan

Determination of some Heavy metals in Sediment samples collected from Elabedia Traditional Gold Mining area – Sudan

Sources and ecological assessment of heavy metal contamination in the surface sediment in Honghai Bay

The sources and ecological environment of heavy metal contamination in the surface sediment of the Honghai Bay were studied, and the contents of seven heavy metals in sediment samples from 20 sampling stations were analysed. Principal Component Analysis (PCA) showed that the contribution rates of the first and second principal component was 60.41% and 16.48%, respectively. The study showed that the major sources of heavy metal contamination were industrial wastewater and municipal wastewater. Combined with the results of correlation analysis between heavy metals and TOC, it was found that Cu, Pb, Zn, Cr and As had a certain degree of homology. The contribution rate of each pollutant variable calculated by PCA method was used to determine the marine sediment pollution index (MSPI) to evaluate the contamination level of heavy metal, and the potential adverse effects of heavy metal contamination on the ecological environment were evaluated by the mean sediment guideline quotient (SQG-Q). The results showed that the sediment conditions were average (MSPI: 40.30-57.92), and the potential adverse biological effects had reached a moderate level (SQG-Q: 0.10-0.21). Heavy metal contamination level of the study area was moderate.

Seasonal Variation of Metallic Contamination of Water and Sediments in Navigation Canal and Industrial Zone South Port Said, Egypt

In the present study, water and sediment samples were collected from Navigation Canal and from Industrial Zone South Port Said to assess heavy metals contamination. It was shown that, the highest mean concentration of heavy metals in water samples was observed in summer, and the lowest mean was observed in winter. It has been made evident that the industrialization in Industrial Zone South Port Said was responsible for the present deteriorating conditions. However, it was shown that, the highest mean concentration of heavy metals in sediment samples was observed in winter, and the lowest mean was observed in summer. Pollution status was evaluated using some indices: geo-accumulation index (Igeo), contamination factor (CF), pollution load index (PLI) and ecological risk index (RI). Based on Igeo, all metal values were unpolluted. On the basis of the values of CF, sediments are high in winter and low in summer. Metals concentrations were in the following order: Ni &gt; Fe &gt; Mn &gt; Pb &gt; Cu &gt; Zn &gt; Co &gt; Cd. According to CF classification, Ni contamination was considerable. RI of winter season can be classified as moderate pollution. No pollution was classified for PLI in all seasons. The decrease in PLI and RI values were indicated dilution and dispersion of metal content with increasing distance from source areas. It is suggested that PLI can give an indication about the trend spatially and temporarily. In addition, it also provides significant data and advice to the policy and decision makers on the contamination degree of the area.

Status of Heavy Metals in Water and Sediments of Canals and Rivers around the Dhaka City of Bangladesh and their Subsequent Transfer to Crops

The study was carried out to observe the present status of heavy metals in water, sediment, soil and plant in the Tejgaon-Rampura-Shitalakhya water channel and the adjacent areas of the Dhaka city as well as to evaluate the heavy metal transfer in the water-soil-plant systems. Water, sediment, soil and plant samples were analyzed to know about lead, cadmium, copper and zinc contents. The findings show that heavy metal concentrations in water, sediment, soil and plant in the study area had the trend: Tejgaon Khal>Rampura canal>Shitalakhya river. Different water quality parameters such as pH, DO, BOD, COD, TDS, and NH3 shows that most of the values are higher than the DoE (Bangladesh) recommended irrigation water standards. The heavy metal concentrations in water varies and are well below the recommended values except for Cd and the trend follow the order Pb>Cd>Zn>Cu. The concentrations of the investigated heavy metals in sediment samples are found higher than the USEPA recommended sediment standards and follow the trend Zn>Cu>Pb>Cd. Similar trends are observed for the heavy metals in soil. The accumulation of heavy metals in plants followed the trend Zn>Pb>Cu>Cd in the Tejgaon and Rampura area while the trend are Zn>Cu>Pb>Cd in plants from Shitalakhya. In most of the cases the results of the tested parameters shows significant variations (at 1% level) from Tejgaon river samples with others.