Sediment Contamination Research Articles

Water and Sediments Contamination by Pesticides in Sassandra River at Guessabo Area (Central-Western of Ivory Coast)

Water and Sediments Contamination by Pesticides in Sassandra River at Guessabo Area (Central-Western of Ivory Coast)

Historical contamination with a current problem: Can mining tailings enhance coastal arsenic pollution?

The coast of Espírito Santo state (Southeast Brazil) is recognized for its environmental arsenic (As) enrichment and, over the years, mining operations have potentialized it. We aimed to evaluate the effect of Rio Doce discharge on As inputs and the role of iron ore tailings from the Fundão dam disaster in enhancing As contamination in the marine sediment. Two scenarios were evaluated: Predisaster and Postdisaster; dry and wet conditions were considered in each period. High As concentrations were found in the Predisaster (28.44 ± 13.53 µg g-1 ), but a significant increase in As was remarkable during the Postdisaster in the wet season, one year after the disaster (maximum of 58.39 µg g-1 ; geoaccumulation index (Igeo ) Class 3, moderately severe pollution). On that occasion, iron (Fe) oxy-hydroxides from tailings were remobilized from the Rio Doce channel and deposited on the continental shelf bottom. Therefore, chemical interactions among Fe, As, and carbonates were enhanced, resulting in As and Fe coprecipitation and the trapping by carbonate adsorption. Rio Doce discharge seems to be the main factor in As inputs to the inner continental shelf when flooding do not occur previously in samplings, which allows further dispersion of contaminants, although this hypothesis should be tested further. Integr Environ Assess Manag 2024;20:159-168. © 2023 SETAC.

Microplastic Contamination in Waters and Sediments in the Selorejo Reservoir, Malang Regency, East Java

Microplastics are small plastic particles under 5 mm in size that have contaminated a lot of ecosystems, both aquatic and on land. The existence of heaps of garbage and the existence of fishing activities around residential areas are some examples of anthropogenic activities that are on the edge and water bodies of the Selorejo Reservoir. This study aims to observe the contamination of various types of microplastics and their abundance in water and sediment samples taken from the Selorejo Reservoir. Sampling was carried out using the selected method (purposive sampling) at five different stations, including the Konto River inlet, Kwayangan River inlet, settlements (blendrang), tourism areas, and reservoir outlets. Each station has 3 transects (as replicates) and about 100 liters of water and 1000 grams of sediment are taken. Destruction of water and sediments uses 30% H2O2 and 30% H2SO4 acid to remove organic components that are still attached and to facilitate observation under a stereo microscope with 400X magnification. Based on the results of an analysis of the abundance of microplastics in the waters of each station, the highest abundance of microplastics was successively found in the Konto river inlet with a total abundance value of 39.27x101 particles/liter, then in the residential part (blendrang) a number of 35.34x101 particles/liter, tourist areas 33.67x101 particles/liter, outlet 30.36x101 particles/liter and Kwayangan river inlet 29.67x101 particles/liter. Meanwhile, the highest total abundance of microplastics found in sediments in the Selorejo Reservoir was found successively in the Konto river inlet with a total abundance value of 3.68 particles/gram, then in the tourist area 2.08 particles/gram, in the Kwayangan river inlet 1.56 particles/gram, in the residential part (blendrang) a number of 1.2 particles/gram and outlets 1.12 particles/gram. Each type of microplastic is then counted based on the amount found. The results of the identification of microplastic contamination in waters and sediments in the Selorejo Reservoir found several types of microplastics, namely fibers, fragments, filaments, and films. The dominating type and color of microplastic is black fiber.

Vertical and Lateral Variation of Ecological Risk Index of Heavy Metals in the Euphrates River Sediments between Heet and Fallujah, Iraq.

The heavy metals (HMs) contamination of river sediments and their ecological risks is a global environmental problem that has attracted the attention of researchers and those interested in environmental protection. The study aims to investigate the ecological hazards of some HMs in sediments of Euphrates River between the cities of Heet and Fallujah, Iraq and their lateral and vertical variations. At three depths—0-30, 30-60, and 60-90 cm—samples of sediment were collected from five sites. Atomic Absorption Flame Emission Spectrophotometer (ASC.7000) was used to measure concentration of Cd, Cr, Cu, Ni, Pb, and Zn. The ecological risk index (ErI) values of metals in Euphrates River sediment in the study area take the following descending order: Cd > Ni > Cu > Cr > Pb > Zn. The ErI levels were low for Cr, Cu, Ni, Pb and Zn and considerable ecological risk for Cd. The obtained results did not show a common lateral variation pattern of the ecological risk of the measured metals. There is a high level of risk for the measured metals at the downstream sampling sites except for the risk from Cd on the contrary. The potential ecological risk of Cd, Cr, Pb and Zn showed a similar vertical variation pattern which in turn reflects a common source or origin for these metals, while copper and nickel showed a different common distribution pattern.

형산강 하천 퇴적물 내 중금속 오염도 및 생태위해성 평가

형산강 하천 퇴적물 내 중금속 오염도 및 생태위해성 평가

A systematic review on metal contamination due to mining activities in the Amazon basin and associated environmental hazards

Metal contamination associated with mining activities has been considered one of the main environmental pollution problems in the Amazon region. Understanding the levels of metal contamination from mining activities requires a good understanding of background metal concentrations, which may vary notably according to the geology/lithology characteristics of the region, soil type, and predominant biogeochemical processes. This review assessed 50 papers and reports published between 1989 and 2020 describing environmental concentrations of different metals and metalloids (As, Hg, Mn, Fe, Cd, Cu, Cr, Pb, Ni, and Zn) in water and sediments of mining and non-mining areas in five geographic regions of the Amazon basin. Metal enrichment caused by mining activities was calculated and exposure concentrations were compared with sediment and water quality standards set for the protection of aquatic life. Significant enrichments of Cd, Cu, Cr, Fe, Hg, Mn, Ni and Zn were observed in mining areas in both sediment and water. Regarding background levels in the different geographic regions, the highest prevalence of metal enrichment (i.e., concentrations 10 to 100-fold higher than mean background values) in sediment samples was found for Fe (100% of samples), Ni (90%), and Mn (69%). For water, high prevalence of metal enrichment occurred for Zn, Mn, and Fe (100% of samples), and for Hg (86%). Hg, Fe, Pb, Cu, Cd, Ni and Zn exceeded water and/or sediment quality standards in a significant number of samples in the proximity of mining areas. This study indicates that mining activities significantly contribute to water and sediment contamination across the Amazon basin, posing hazards for freshwater ecosystems and potentially having human health implications.

Improved Calculations of Heavy Metal Toxicity Coefficients for Evaluating Potential Ecological Risk in Sediments Based on Seven Major Chinese Water Systems.

Several methods have been used to assess heavy metal contamination in sediments. However, an assessment that considers both composite heavy metal speciation and concentration is necessary to accurately study ecological risks. This study improved the potential ecological risk index method and calculated the toxicity coefficients of seven heavy metals: Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn). The newly calculated toxicity coefficients were validated by using previously published heavy metal distribution data of the Henan section of the Yellow River. The calculation procedure is based on the principle that the abundance of heavy metals in the environment and their bioavailable forms affect the toxicity of heavy metals. The toxicity coefficients for the seven heavy metals were calculated as follows: As = 10, Cd = 20, Cr = 5, Cu = 2, Ni = 5, Pb = 5, Zn = 1. Ecological risk assessment of the Henan section of the Yellow River using the improved toxicity coefficients revealed that the ecological risk of Cd and total heavy metals is higher than previous calculations, reaching the strength and moderate risk levels, respectively. The improved potential ecological risk index method is more sensitive to heavy metal pollution and thus provides a better indication of ecological risk. This is a necessary improvement to provide more accurate pollution assessments.

Level of Some Heavy Metal Contamination of Water and Sediments of River Pil-Gani Plateau State Nigeria

Level of Some Heavy Metal Contamination of Water and Sediments of River Pil-Gani Plateau State Nigeria

Probing the national development from heavy metals contamination in river sediments

Equal access to clean water for all is the 6th of the United Nations Sustainable Development Goals. River sediment is an important sink of heavy metals discharged by human activities, and also a critical risk source for drinking water safety. We compared the concentrations of heavy metals in the river sites of countries with various degrees of development, and obtained the distribution results that can fit the Environmental Kuznets Curve. The risk assessment of water sources can correlate or probe socio-economic feedback to the environment. We hope to focus on the environmental changes together with the global riverbeds, rather than just local case studies. Worryingly, humanity has not escaped the law of Environmental Kuznets Curve. There are more than 4 billion people living in the early stage of industrialization nowadays. With their increasing affluence and metal purchasing power, new heavy metal pollution problems will occur in the places with few reports. The development of the national economies, as revealed by donor-acceptor relation models in resource acting force, requires the search for innovative patterns to achieve global progress that is more equitable, efficient and sustainable.

Environmental hazard assessment and metal contamination in coastal sediments

In order to reduce contamination levels from diverse sources, it is important to understand the factors affecting the natural ecosystems that are impacted by coastal and marine pollution. In this study, we used GIS and remote sensing techniques to investigate and evaluate the distribution of heavy metals (Fe, Mn, Zn, Cr, Pb, Co, and Cu) in surface sediments along Tamil Nadu's East Coast (from Besant Nagar to Sathurangapattinam). The CF and Igeo of metals indicate that sediments contain no evidence of Fe, Mn, or Zn metal pollution in the sediments, with only mild contamination from Co, Cu, and Pb. In contrast, the sediment samples were found to be significantly contaminated with Cr. Heavy metal contamination occurs in the following order, according to our research: Cr > Pb > Cu > Co > Mn > Zn > Fe. Except for sites 8, 10, 11, and 13, where PLI>1 implies that there is no pollution in this area, the PLI values show that most of the locations are contaminated. The ecological risk index (ERI) values for five metals in the study areas are as follows: Cr > Pb > Cu > Mn > Zn. The sediment samples fall into the low-risk and highly polluted to dangerous sediment categories for SPI, according to the Risk index (RI). Based on the Mean Effect Range-Median Quotient (M-ERM-Q), Cu, Pb, Zn, and Cr metals in the research region have a 9–21% probability of being harmful. Statistical approaches show that the majority of heavy metals in sediments are of natural origin. The spatial distribution of heavy metals in surface sediments provides the conceptual framework for practical strategies to protect coastal areas. Many shreds of evidence indicate that anthropogenic inputs from the surrounding land area are primarily responsible for the deposition of these heavy metals in the coastal zone.

Historical trends and pollution assessment of heavy metals in core sediments from the Jiangsu offshore area, China

To assess the historical changes and pollution status of heavy metals, core sediments from the Jiangsu offshore area of China were systematically sampled and analyzed to determine the concentrations of Cu, Pb, Zn, Cr, Cd, As, Hg, Li, Ni, and Co. The stratigraphic framework of the SYS-1501 core was identified based on sedimentary structures, sedimentary facies, grain size, and comparison with seismic reflections and other well-studied cores from adjacent areas. The Pearson’s correlation coefficient, enrichment factor (EF), geoaccumulation index (Igeo), and principal component analysis (PCA) were used to distinguish the sources and assess the pollution risk of heavy metals. The results showed no elemental enrichment or contamination in the core sediments, and the high EF and Igeo values of Pb, As, Hg, and Li may be related to the selected background values of these metals. Except for Mn, all other metals and TOC exhibited similar vertical distribution patterns that were closely related to the mean grain size (Mz). Almost all the heavy metals were positively correlated with Al, Fe, and Mz, and all had high loadings on PC1, indicating that they are naturally sourced. Manganese (Mn) had a high loading on PC2, mainly representing the effect of marine authigenic elements on the sediments. Historical changes in the heavy metals in the core sediments were predominantly related to the sedimentary environment, sediment sources, and Mz.

Potentially toxic elements contamination, risk and source analysis in sediments of Beiyun River supplied with reclaimed water, China

It is unknown the contribution rate of reclaimed water recharge to the accumulation of potentially toxic elements and the key factors affecting the speciation of potentially toxic elements in highly polluted urban river and lake sediments that have been replenished with reclaimed water. This study aims to clarify the contamination, risk and source analysis of potentially toxic elements pollution in the Beiyun River, (Beijing, China) which is a heavily polluted urban river. All eight potentially toxic elements have different degrees of ecological risk. Cr and Cu pose carcinogenic and non-carcinogenic risks to adults and children, whereas Ni poses carcinogenic risks to children only. Importantly, our proposed method based on meta-database construction combined with traditional analysis can effectively quantitatively evaluate the contribution rate of reclaimed water supply to potentially toxic elements in river sediments. The contribution of the reclaimed water supply project to potentially toxic elements was as high as 67%, followed by agricultural sources (26%), and atmospheric deposition (7%). Interestingly, we also used variation partitioning analysis combined with correlation analysis to identify key factors affecting the speciation of potentially toxic elements. The cations and microbial communities in the reclaimed water had the highest individual interpretation for the exchangeable fraction (29.4%) and reducible fraction (54%), respectively. The oxidizable fraction was affected by microbial communities, cations, and nutrient ions and had the strongest synergistic effect, with a co-influence of 37.5%. The residual fraction was the most stable, and the individual contribution of the microbial communities and their variance was high (42.7%). Therefore, disentangling the mechanism of potentially toxic elements enhances the management of pollutants in the urban rivers and lake recharged by reclaimed water.

The distribution of metal and petroleum-derived contaminants within sediments around oil and gas infrastructure in the Gippsland Basin, Australia

As oil and gas infrastructure comes to the end of its working life, a decommissioning decision must be made: should the infrastructure be abandoned in situ, repurposed, partially removed, or fully removed? Environmental contaminants around oil and gas infrastructure could influence these decisions because contaminants in sediments could degrade the value of the infrastructure as habitat, enter the seafood supply if the area is re-opened for commercial and/or recreational fishing, or be made biologically available as sediment is resuspended when the structures are moved. An initial risk hypothesis, however, may postulate that these concerns are only relevant if contaminant concentrations are above screening values that predict the possibility of environmental harm or contaminant bioaccumulation. To determine whether a substantive contaminants-based risk assessment is needed for infrastructure in the Gippsland Basin (South-eastern Australia), we measured the concentration of metals and polycyclic aromatic hydrocarbons (PAHs) in benthic sediments collected around eight platforms earmarked for decommissioning. The measurements were compared to preset screening values and to background contaminant concentrations in reference sites. Lead (Pb), zinc (Zn), PAHs and other contaminants were occasionally measured at concentrations that exceeded reference values, most often within 150 m of the platforms. The exceedance of a few screening values by contaminants at some platforms indicates that these platforms require further analysis to determine the contaminant risks associated with any decommissioning option.

Spatio-temporal variation and hazard assessment of potentially toxic metal element contamination in sediments and water before and after a water-level fluctuation cycle in the Three Gorges Reservoir, Wanzhou, China.

Previous investigations on heavy metals in the water-sediment compartment focused on their spatial distribution, and the influence of sediment pH and organic matter (OM) on metal environmental occurrences. However, there are limited studies on the effects of physicochemical properties on the migration and transformation of heavy metals in the water-sediment compartments. This study investigated the relationship between the physicochemical properties of sediments and the distribution and chemical speciation of heavy metals, and the potential environmental risk of heavy metals in water and sediment using Risk Assessment Code (RAC) values and the Tessier five-step extraction method. Adsorption and desorption experiments showed that the sediment had weak adsorption and the strongest desorption capacity for Cd. Results of the pH, OM, surface element content, and X-ray diffraction (XRD) patterns suggested that cadmium (Cd) was more likely to partition into the water phase from the sediment during the flooding and water storage periods. When pH was 7-8 and OM content was 3.6-5.9%, the sediment-water distribution coefficient of Cd was low due to its large ionic radius, and the surface adsorption sites were saturated by other elements. These studies can provide a theoretical basis for the management and pollution control of the Three Gorges Reservoir.

Assessment of heavy metal contamination in the surface sediments of the Vedaranyam coast, Southern India

The marine sediments of the Vedaranyam coast were examined for their heavy metal contamination largely contributed by natural and anthropogenic activities. Sediment samples were collected and assessed for metals such as chromium (Cr), copper (Cu), manganese (Mn), iron (Fe), Nickel (Ni), zinc (Zn), and cobalt (Co). The individual toxic risk index (TRIi) of metals in this study is significantly variable for Cr (0.88–1.10), Cu (1.78–2.73), Zn (2.33–4.81) and Ni (1.10–4.62). TRIi in the sediments is below 5 for Cr, Cu, Zn, and Ni suggesting the absence of any toxic risk in the aquatic life. To assess the natural and anthropogenic contamination as well as to know the sediment quality, various indices such as the geo-accumulation index, enrichment factor, pollution load index, and contamination factor were computed. The enrichment factor result shows that the heavy metals are primarily from anthropogenic sources. There is a high positive correlation among the heavy metals, indicating a similar origin.

Zostera noltei response to transplantation into historically Hg-contaminated sediments (A mesocosm experiment): Growth, bioaccumulation and photosynthetic performance

The present study aimed to evaluate the effectiveness of seagrass recolonization as a nature-based solution for the recovery of a coastal area historically contaminated by mercury (Laranjo Bay, Ria de Aveiro, Portugal). A mesocosm approach was employed to assess the resistance of Zostera noltei to transplantation into contaminated sediments collected in-situ (0.5–20 mg kg−1 Hg). At each sampling time (15, 30, 60, 120 and 210 days), the resistance of transplanted Z. noltei was evaluated through growth parameters (biomass and coverage area), photosynthetic performance and elemental composition. Although some significant differences (p ≤ 0.05) were observed between treatments, essentially associated with the elemental composition of plant tissues, the most relevant variations were associated with seasonality. Overall, plants were found to not be affected by sediment contamination, under the tested concentrations, suggesting that recolonization with Z. noltei can be an effective restoration strategy for historically contaminated coastal areas.

Microplastic Contamination in the Coastal Environment: A Case Study from the Mae Klong Estuary, Samut Songkhram

The mangrove sediment from the Mae Klong River (MK) and Klong Khon Canal (KK) revealed the microplastics contamination in the Mae Klong Estuary environment. Microplastic analyses were analyzed by using ZnCl2 density separation and H2O2 digestion process. The average concentrations of microplastic was 580 and 1690 items kg-1 dry weight in the samples from MK and KK. MK sediment contained more coarse grain than KK sediment. The lower microplastic concentration in MK was mainly related to the runoff through the sea. In contrast, the abundant microplastic in KK was possibly caused by the low transportation energy of sediment in the tidal flat that associated with deposition of fine grain. In addition, the microplastics were mainly polyester fiber originating from laundry processes or transport from the vicinity. The contamination in mangrove sediment in this study may encourage communities and the government to be more aware of waste management.

Distribution, characterization and contamination risk assessment of microplastics in the sediment from the world's top sediment-laden estuary

Microplastics (MPs) have gained a serious attention as an emerging contaminant throughout the world because of their persistence and possible risks to aquatic ecosystems and human well-being. However, knowledge on MPs contamination from sub-tropical coastal systems is limited, and no study has been conducted on the MPs contamination in sediment from one of the highest sediment-laden estuaries, Meghna River, in the world. This is the first study to examine the quantity, morpho-chemical characteristics and contamination risk level of MPs from this large scale river. MPs were extracted from the sediment samples of 10 stations along the banks of the estuary by density separation, and then characterized using a stereomicroscope and Fourier Transform Infrared (FTIR) spectroscopy. The incidence of MPs varied from 12.5 to 55 item/kg dry sediment with an average of 28.67 ± 10.80 item/kg. The majority (78.5%) of the MPs were under 0.5 mm in size, with fibers being the most (74.1%) prevalent MPs type. Polypropylene (PP) was found to be the predominant polymer (53.4%), followed by polyethylene (PE, 20%), polystyrene (PS, 13.3%), and polyvinyl chloride (PVC, 13.3%). The highest occurrence of PP indicted the MPs in the estuary might be originated from clothing and dying industries, fishing nets, food packages, and pulp industries. The sampling stations were contaminated with MPs as shown by the contamination factor (CF) values and pollutant load index (PLI), both of which were >1. This study exposed new insights on the status of MPs in the sediments of the Meghna River, laying the groundwork for future research. The findings will contribute to estimate the global share of MPs to the marine environment.

Spatial and seasonal use of biomarkers in dreissenids: implications for biomonitoring.

In addition to pollution, organisms are exposed to natural variations of the biotic and abiotic factors of their environment. A battery of sub-cellular biomarkers has been measured seasonally in several populations of both Dreissena polymorpha and Dreissena rostriformis bugensis. To observe and understand the variability associated with biomarker responses, water physicochemistry, sediment contamination, and internal concentrations of contaminants in soft tissues were also considered. Results evidenced seasonal, inter-specific, and inter-populational variability of the measured responses, highlighting the needs (1) to acquire long-term data on the studied populations and (2) to incorporate environmental parameters and contamination in the interpretation of biological responses. From a biomonitoring perspective, significant relationships were identified between biomarkers, internal concentrations of contaminants in soft tissues, and sediment contamination in D. r. bugensis and, to a lesser extent, in D. polymorpha. The detailed interpretation of each biomarker of the battery measured is complex, but a global analysis of all biomarkers at once allows to obtain this signature of the contamination of the studied sites.

Heavy Metal Contamination and Potential Ecological Risk Assessment in Sediments of Lake Bafa (Turkey)

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