Metal Contamination In Sediments Research Articles

The spatial distribution of benthic foraminifera in the Pearl River Estuary, South China and its environmental significance

Thirty surface sediment samples were collected from the Pearl River Estuary, South China, and benthic foraminifera were analyzed in order to understand the relationship between foraminiferal assemblages and environmental parameters. Multivariate analyses showed that the foraminferal assemblages (i.e., abundance and diversity) are correlated with the hydro-sedimentary gradients within the estuary. In addition, the dominant faunal composition seems to be largely influenced by food availability and trace metal contamination in surface sediments. A comparison with historical data from 1980s demonstrated that the foraminiferal abundance and diversity in the lower estuary have dramatically decreased over the last three decades, together with a significant shift in the dominant species. This is most likely due to the cumulative impacts of eutrophication and Cu contamination caused by human activities in the Pearl River basin. This work confirms the value of benthic foraminifera as bio-indicators in polluted estuarine environments.

A Case Study on Metal Contamination in Water and Sediment near a Coal Thermal Power Plant on the Eastern Coast of Bangladesh

This study has evaluated the potential ecological risk and human health risk for the contamination of nine elements (Cu, Cr, Mn, Zn, As, Pb, Co, Fe, and Sr) in water and sediment samples in two seasons, i.e., before and after rainy season, by calculating several pollution indices such as pollution load index (PLI), potential ecological risk (PER), and target hazard quotient (THQ). Samples were analyzed for elemental concentration using energy dispersive X-ray fluorescence (EDXRF) spectrometry. This study found that waters in the Kutubdia channel are safe and standard for aquatic organisms. In addition, the study area’s elemental concentration in water and sediments is still safe but moderately enriched with Zn and Cu. The elemental concentration in water was observed to be high in the pre-monsoon season and vice versa in the sediment study. The result also reveals no potential ecological risk (PER < 4) in the study site. However, the health risk index showed a noncarcinogenic risk (THQ > 1) for children and adults regarding the inhalation process where manganese was dominant. Apart from this, the pollution source was also identified by multivariate statistical analysis, including cluster analysis (CA) and principal component analysis (PCA)—and a natural pollution source prevalent was found.

Ecological risk assessment of trace metals in sediment from the Old Brahmaputra River in Bangladesh

ABSTRACT The assessment of trace metal contamination in river sediments is crucial for suggesting effective strategies to protect aquatic ecosystem health. In this study, six toxic trace metals (As, Cd, Cr, Hg, Ni and Pb) in the surface sediments from the Old Brahmaputra River in Bangladesh were examined to evaluate the potential ecological risks. Sediment samples were collected in September 2018 and analysed by an atomic absorption spectrometer. Mean concentrations (mg/kg dw) of trace metals were in the order of Ni (43.49) > Cr (30.25) > Pb (14.29) > As (3.74) > Hg (0.16) > Cd (0.03). Spatially the sedimentary metals did not vary significantly. Source analyses revealed anthropogenic origin for most of the metals. The contamination factor, enrichment factor and geoaccumulation index (I geo) revealed a low degree of contamination for all cases except Hg, which showed a moderate degree of contamination. According to the sediment quality guidelines and sediment screening values, only Cr, Hg and Ni were high enough to cause detrimental effects in aquatic organisms. The potential ecological risk factor (Er i ) and potential ecological risk also revealed low to moderate ecological risk. Comprehensively, the river was in the uncontaminated to moderately contaminated level with low ecological risk.

Bioaccumulation and chronic toxicity of arsenic and zinc in the aquatic oligochaetes Branchiura sowerbyi and Tubifex tubifex (Annelida, Clitellata).

Oligochaetes feed on bulk sediment and penetrate the sediment through the construction of burrows, making them especially vulnerable to sediment metal contamination. However, the few oligochaete species that have been tested to date are almost exclusively temperate test species. Although the warmwater adapted species Branchiura sowerbyi has been indicated as a promising candidate for tropical sediment toxicity testing, few (especially chronic) studies have been conducted so far to confirm this. Therefore, the aim of the present study was to evaluate the bioaccumulation and chronic 28d lethal and sublethal toxicity of arsenic (As) and zinc (Zn) to both the warmwater-adapted B. sowerbyi and the coldwater-adapted oligochaete Tubifex tubifex for comparison. Arsenic was more toxic to both oligochaete species than Zn. Inter- and intra-species variability in toxicity values of the two test species and other benthic invertebrates was within an order of magnitude. However, B. sowerbyi was the most sensitive species to As even for sediment concentration (EC50: 36.6 ± 2.1 µg/g and 147.1 ± 21.7 µg/g, for B. sowerbyi and T. tubifex, respectively) and for tissue concentration (ER50: 9.2 ± 0.9 µg/g and 887.0 ± 35.0 µg/g, for B. sowerbyi and T. tubifex, respectively). Finally, the Tissue Residue-effects Approach (TRA) using Effective Tissue Residues appears to be a promising way forward in advancing in this since it considers internal body concentrations.

Ecological risk assessment of heavy metals in the sediments of a Mediterranean lagoon complex.

This study examines the heavy metal contamination in the surface sediments of six coastal lagoons in Northern Greece (Nestos River and Vistonikos complexes) in relation to particle size distribution, organic carbon, total phosphorus and total Kjeldahl nitrogen. Furthermore, the contamination degrees and the ecological risks were assessed using different indicators. The study of heavy metals in lagoon's sediments is important in evaluating natural contamination against anthropogenic impact, and consequently, providing knowledge that could lead to management measures to reduce heavy metal environmental risks. Lafri Lagoon is characterized by the highest metal levels in all elements, while Agiasma and Porto Lagos by the lowest. Comparison of metal (As, Cd, Cr, Cu, Mn, Pb, Zn and Ni) levels with Sediment Quality Guidelines showed that As and Cr were found above the toxic effect threshold values. Potential toxicity (RI) seems influenced mostly by As and Cd. CD and PLI values classified the lagoons under study as "very highly contaminated" and "polluted", respectively.

Ecological Risk Assessment of Heavy Metals in Adjoining Sediment of River Ecosystem

The present study was focused on heavy metal distribution patterns and the associated ecological risk assessment in the adjoining sediment of the Hindon River in Muzaffarnagar Region (U.P.), India. Lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), nickel (Ni), iron (Fe), aluminum (Al), sodium (Na), and potassium (K) were estimated from six sediment samples (Atali A and B, Budhana A and B, and Titavi A and B). The concentration of the heavy metals Zn, Pb, Cu, Ni, and Cd ranged from 25.5–74.7 mg kg−1, 29.8–40.6 mg kg−1, 7.0–29.2 mg kg−1, 14.7–21.8 mg kg−1, and 0.96–1.2 mg kg−1, respectively and followed the sequence Zn > Pb > Cu > Ni > Cd, while major elements followed the sequence Na > Fe > Al > K. The enrichment factor (EF) and geo-accumulation index (Igeo) revealed that Atali A showed the highest enrichment and followed the sequence Zn > Cu > Pb > Ni > Cd. Contamination factor (CF) and contamination degree (CD) depicted that all of the sites (except Titavi B) were moderately to considerably contaminated. The highest degree of contamination (CF, CD, and PLI, pollution load index) was observed at Titavi A followed by Atali A and Budhana A. Eco-toxicological risk assessment (RI) indicated that the sites were moderately contaminated, predominantly by Ni and Pb and Zn. The results revealed that the metal contamination in sediment is alarming and might pose an adverse threat to ecosystem health.

Spatial and temporal assessment of metals contamination in the surface sediments of biogenic intertidal reefs of Sabellaria alveolata (Annelida: Polychaeta) from Essaouira protected coastal area (Atlantic coast of Morocco)

In the present study, we assessed the spatial and temporal distributions of metal contents and their environmental risks in the surface sediments from Essaouira protected coastal area (Atlantic coast of Morocco). Surface sediment samples of the biogenic reefs of Sabellaria alveolata (Annelida: Polychaeta) were collected seasonally, and the fine fraction (<63μm) analysed using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). The sediment characteristics of this coastal zone were comparable to other Moroccan coastlines, and the sequence of metal concentrations decreased Al > Fe > Zn > Cr > Cu > Pb > Cd. Concentrations were lower than mean Earth crustal contents and world average background levels except for Cd. Spatial and temporal variations of metals were highly significant, and largely determined by geochemical background properties and inputs of terrigenous material except for Cd which was associated with upwelling phenomena. Comparison with sediment quality guidelines (SQGs) and ecotoxicological values indicated few exceedances with regard to most metals except for Cd, Cr and Cu. Consequently, the dredged sediment may be dumped at sea with little likelihood of adverse biological effects. However, some sediments had a moderately high Cd content, especially during summer and warrant more detailed assessment.

Assessment of metal contamination in sediments induced by small ships around lighters wharf in Southwest Korea

Assessment of metal contamination in sediments induced by small ships around lighters wharf in Southwest Korea

Heavy Metal Contamination in Sediments and Its Potential Ecological Risks in Youtefa Bay, Papua Province, Indonesia

Heavy Metal Contamination in Sediments and Its Potential Ecological Risks in Youtefa Bay, Papua Province, Indonesia

Contamination of Urban Watersheds: the Case of Arroio Moinho, Porto Alegre, Rio Grande do Sul, Brazil

This article aims to analyze the contamination of water and bottom sediment at Arroio Moinho (Mill Stream), in Porto Alegre (Rio Grande do Sul, Brazil). From two sample collections, a series of diagnostic measurements were carried out, such as: a) physical-chemical and biological analysis of the water; b) water quality index (WQI); c) metal contamination, granulometric and mineralogical analyses of the bottom sediment; d) total organic carbon (TOC); e) categorization into water quality classes; f) contamination factor (CF) and geoaccumulation index (Igeo) geoindicators; g) analysis of per capita income and population density. The analytical results of the water at the two sample locations exceeded the limits established by Class 4 (restricted use). The WQI revealed the worst level (very bad in 2012 and bad in 2018) at all sampling points. The bottom sediment analysis showed that the spring has a low fine-grained fraction content (3%) and TOC levels between 8 and 17%. However, the sediments revealed high levels of metals such as Zn and Cu and low to moderate Pb levels. These results allowed the stream to be classified as Class 3 in terms of soil quality, requiring identification of the source of the pollution and ongoing inspection to monitor contamination.

Ecological Risk Due to Heavy Metal Contamination in Sediment and Water of Natural Wetlands with Tourist Influence in the Central Region of Peru

In this study, the quality of sediment and surface water in two natural wetlands, Paca and Tragadero, in the central region of Peru was evaluated using pollution indices, including the geoaccumulation index, pollutant load index, modified pollution degree, potential ecological risk index, and site rank index, for four heavy metals. Principal component analysis was used to identify potential metal contaminant sources. The determination of Fe, Zn, Pb, and As was performed by flame atomic absorption spectrophotometry. The average concentrations of metals in the sediments of both lagoons decreased in the order Fe &gt; Zn &gt; Pb &gt; As. The analysis of the contamination indices determined that As and Pb are the elements that contribute the most to environmental degradation in both wetlands. There is a strong correlation between the values of potential ecological risk and the modified degree of contamination, revealing that the Paca wetland has a moderate degree of contamination and potential ecological risk, while Tragadero presents a high degree of contamination and considerable potential ecological risk. The application of the site rank index showed that more than 50% of the sampling sites have between high and severe contamination. The principal component analysis presented 79.2% of the total variance. Finally, the results of this study are essential in order to carry out preventive actions for environmental protection in these lake ecosystems of great importance for many activities, such as bird watching.

The chemical characterization and its relationship with heavy metals contamination in surface sediment of Marchica Mediterranean Lagoon (North of Morocco).

The sediments were studied according to the granulometric characteristics, the geochemical analyses of the sediments (organic matter (OM), carbonate, and pH), the analyses of heavy metals (HM) characteristics, and their contamination status in the ecological system and the mineralogical analysis of the sediments at 8 sites spread over the Marchica lagoon (NE-Morocco). Our results showed that the opening of the new wide and deep pass affected the spatial distributions of the metals, which were closely related to fine fraction and sediment OM concentration. In the north and southeast lagoon zones presented low concentrations of the HM, fine particles (clay), OM, whereas the south and the center of the lagoon were heavily loaded with HM and OM, corresponding to the trapping zones by fine particles. The results of mineralogy analyses have revealed the predominance of non-clay minerals such as quartz and calcite, and for the clay fractions of sediments showed that they are formed of illite, kaolinite, smectite, and chlorite in highly variable proportions; illite was the most dominant clay in the north-western Marchica lagoon sediments. Therefore, the HMs are fixed by clay colloids having a high cation exchange capacity with smectite-chlorite-kaolinite assembly.

Trace Metal Contamination of Bottom Sediments: A Review of Assessment Measures and Geochemical Background Determination Methods

This paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination of the assessment measures. Geochemical and ecotoxicological classifications are presented that may prove useful for sediment evaluation. Among the geochemical indices, several individual pollution indices (CF, Igeo, EF, Pi (SPI), PTT), complex pollution indices (PLI, Cdeg, mCdeg, Pisum, PIAvg, PIaAvg, PIN, PIProd, PIapProd, PIvectorM, PINemerow, IntPI, MPI), and geochemical classifications are compared. The ecotoxicological assessment includes an overview of Sediment Quality Guidelines (SQG) and classifications introduced nationally (as LAWA or modified LAWA). The ecotoxicological indices presented in this review cover individual (ERi) and complex indices (CSI, SPI, RAC, PERI, MERMQ). Biomonitoring of contaminated sites based on plant bioindicators is extensively explored as an indirect method for evaluating pollution sites. The most commonly used indices in the reviewed papers were Igeo, EF, and CF. Many authors referred to ecotoxicological assessment via SQG. Moreover, PERI, which includes the toxic response index, was just as popular. The most recognised bioindicators include the Phragmites and Salix species. Phragmites can be considered for Fe, Cu, Cd, and Ni bioindication in sites, while Salix hybrid cultivars such as Klara may be considered for phytostabilisation and rhizofiltration due to higher Cu, Zn, and Ni accumulation in roots. Vetiveria zizanoides demonstrated resistance to As stress and feasibility for the remediation of As. Moreover, bioindicators offer a feasible tool for recovering valuable elements for the development of a circular economy (e.g., rare earth elements).

Contamination and ecological risk of heavy metals in Al-Uqair coastal sediments, Saudi Arabia

The level of heavy metal contamination and ecological risk, as well as the sources of contamination, of 35 sediments from the Al-Uqair coast, Saudi Arabia, were determined via inductively coupled plasma mass spectrometry. The average concentrations (dry weight) were highest for Fe (8091.51 μg/g), followed by Al (1816.60), As (14.99), Cu (11.27), Zn (7.62), Pb (3.88), Mn (3.82), Cr (3.67), Hg (2.40), Se (0.68), Ni (0.57), Cd (0.07), and Sb (0.06). The average TOC and heavy metal values, except Hg and As, were much lower than many coastal sediments elsewhere. The sediments had moderate-to-high heavy metal pollution, especially with high Hg contamination and substantial Se and As enrichment. Moreover, the sediments were at a high ecological risk for Hg, As, and Cd, moderate risk for Cu, and no-to-low risk for Pb, Zn, Ni, Cr, and Sb. Hg, Cd, Cr, As, Se, Cu, Sb, Pb, Ni, and Zn were likely from lithogenic and anthropogenic sources, including rock weathering, agricultural runoff, and untreated domestic sewage. However, Al, Fe, and Mn were naturally derived.

Effect of a tropical cyclone on the distribution of heavy metals in the marine sediments off Kameswaram, Southeast coast of India

Cyclones and heavy rainfalls are the main reasons for incessant environmental aggravation in the coastal regions and the distribution of pollutants from the contaminated terrestrial areas to the offshore regions. Twenty-five surface sediment samples were collected off Kameswaram, SE coast of India, and assessed for their geochemical and sedimentological characteristics post Cyclone Gaja. Sediment texture and various geochemical analyses were carried out to assess the metal distribution in the study area. Environmental impacts caused by heavy metal contamination in the marine sediments were assessed using different sediment pollution indices and it was found that metals such as Cu, Zn, Ni, and Co were moderately contaminated. Fe and Cr were uncontaminated to moderately contaminated, and Mn fall under the uncontaminated category. Multivariate statistical analyses revealed that the enrichment of organic-rich mud helps in entrapping the heavy metals, thus polluting the environment. Moreover, these metals were mainly derived from anthropogenic activities.

Time-series monitoring and ecological risk assessment of heavy metal pollution in Mahanadi estuary, east coast of India

Mahanadi estuary is situated in the eastern part of India with several industries along its bank, which makes the system highly vulnerable to different types of pollutants. To assess the coastal pollution due to possible heavy metal contamination in the surface sediment of the estuary, seasonal observations (pre-monsoon, post-monsoon, and winter) were made from a time-series monitoring station near the estuary mouth. The study showed that the average concentrations of nine heavy metals were in the order of Fe> Pb> Cr >Zn >Co> Cu> Ni> Cd> Hg in both pre-monsoon and post-monsoon, whereas in winter their order was Fe >Pb >Cr> Zn> Ni> Cu> Co> Cd> Hg. The one-way ANOVA of metal concentrations shows significant seasonal variations (p<0.01) except for Hg, Cu, Zn, and Fe. The high concentration of metals in post-monsoon and winter indicated seasonal influences of potential sources in the upstream. The concentrations of Cd, Pb, Co, Ni, Zn, and Hg showed prominent tidal variation, and Cd concentration was high only in ebb tide in both pre-monsoon and post-monsoon. The pollution indices — Enrichment Factor (EF), Geo-accumulation Index (Igeo), and Pollution Load Index (PLI) along with Potential Ecological Risk Assessment (PERI) were used for the environmental assessment of Mahanadi estuary sediment collected during pre-monsoon, post-monsoon, and winter season. The high EF of Pb and Cd shows contamination of sediments by these metals from external sources such as industrial and other anthropogenic activities. Pollution indices showed that the sediment of the Mahanadi estuary is not contaminated with respect to metals except Cd. Numerical Sediment Quality Guidelines, applied to assess adverse biological effects of these metals, suggested possibilities of occasional biological effect due to Cd.

The mussel caging approach in the assessment of trace metal contamination in southern Mediterranean coastal waters: a multi-biomarker study.

In the framework of the biomonitoring programme of the Gulf of Annaba (north-eastern Algeria), this study aims to assess the health status of the Gulf by transplanting the brown mussel Perna perna (Linnaeus 1758) for 12 weeks (June 2017-August 2017) at three sites. The concentrations of copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) and as well as a battery of enzymatic and non-enzymatic biomarkers were measured in mussels before and after the transplantation period. Furthermore, analysis of trace metals was performed on the surface layer of the sediment of all the sites. A significant increase in the Cu and Pb concentrations in the mussel dry tissues was observed after the transplantation period and followed the order of metal contamination of the surface layer sediments, indicating a relationship between the bioaccumulation of metals and their bioavailability at each site. Unlike those of Cu and Pb, Cd and Zn concentrations did not reach significant levels of bioaccumulation at any of the three study sites. The biomarker response results were complementary to the measured metal concentrations in the mussel tissues and were associated with the metal accumulation index. Metal bioaccumulation in mussels and supporting biomarker response results identified the most important pollution point sources in the area.

Assessment of Heavy Metal Pollution Levels in Sediments and of Ecological Risk by Quality Indices, Applying a Case Study: The Lower Danube River, Romania

It is a well–known fact that heavy metal pollution in sediments causes serious problems not only in the Danube basin, but also in the large and small adjacent river streams. A suitable method for assessing the level of heavy metals and their toxicity in sediments is the calculation of pollution indices. The present research aims to assess heavy metal pollution in the Lower Danube surface sediments collected along the Danube course (between 180 and 60 km) up to the point where the Danube River flows into the Danube Delta Biosphere Reserve (a United Nations Educational, Scientific and Cultural Organization—UNESCO, protected area). In addition, this monitored area is one of the largest European hydrographic basins. Five heavy metals (Cd, Ni, Zn, Pb, Cu) were analyzed in two different seasons, i.e., the autumn of 2018 and the spring of 2019, using the Inductively Coupled Plasma Mass Spectrometry (ICP– MS) technique. Our assessment of heavy metal pollution revealed two correlated aspects: 1. a determination of the potential risks of heavy metals in sediments by calculating the Potential Ecological Risk Index (RI), and 2. an evaluation of the influence of anthropogenic activities on the level of heavy metal contamination in the surface sediments, using three specific pollution indices, namely, the Geo–Accumulation Index (Igeo), the Contamination Factor (CF), and the Pollution Load Index (PLI). The results of this pioneering research activity in the region highlighted the presence of moderate metal (Ni and Cd) pollution and a low potential ecological risk for the aquatic environment.

Assessment of Heavy Metal Contamination in Sediments of the Shitalakhya River, Bangladesh

Sediment samples collected from the river Shitalakhya, Bangladesh, were analyzed using atomic absorption spectroscopy (AAS) to investigate site-to-site (spatial) and seasonal (i.e., dry, premonsoon, post-monsoon) variation of Cr, Mn, Ni, Cu and Zn. The mean concentrations of Cr, Mn, Ni, Cu and Zn were 22.37 ± 6.09, 612.59 ± 160.08, 54.11 ± 11.21, 50.36 ± 9.40 and 103.62 ± 62.74 mg/kg in the dry, 31.58 ± 5.22, 569.71 ± 112.16, 58.35 ± 7.82, 49.93 ± 17.36 and 110.88 ± 95.83 mg/kg in the pre-monsoon and 18.09± 6.32, 567.02 ± 115.55, 50.89 ± 6.58, 39.75 ± 4.56 and 55.22 ± 11.33 mg/kg in the post-monsoon, respectively. Based on the metals’ concentrations, no considerable difference was observed among the three seasons, but the concentrations were slightly elevated in the dry and pre-monsoon compared to that in the post-monsoon with respect to site-to-site variation. Among the metals examined, concentrations of Ni and Cu were elevated because of the use of oxides of these heavy metals as catalysts in the ammonia plant. The following statistical indices i.e., Pearson correlation matrix, geo-accumulation index (Igeo), contamination factor (Cf), degree of contamination (Cd), pollution load index (PLI) and ecological risk potential (RI) factors were taken into account to assess the heavy metals contamination of the sediments. According to the values of the statistical indices for Cr, Mn, Ni, Cu and Zn, it is concluded that the study area was with low contamination while concentrations of Ni and Cu were higher than the Threshold Effect Level (TEL) and Toxicity Reference Value (TRV) values suggesting unsafe to use the sediments for vegetation and other uses.

Assessment of metal enrichment and contamination in surface sediment of Mandovi estuary, Goa, West coast of India

Assessment of metal enrichment and contamination in surface sediment of Mandovi estuary, Goa, West coast of India