Sediment Pollution Research Articles

Occurrence and distribution of microplastics in surface sediments of a typical river with a highly eroded catchment, a case of the Yan River, a tributary of the Yellow River

Investigation of microplastic contamination in riverbed sediments can help clarify long-term microplastic pollution and establish prevention measures in watersheds. However, little research has been conducted on riverbed sediment pollution on the Loess Plateau, a highly eroded area in Northwest China. This research investigates the Yan River as a case study. The occurrence and distribution of microplastics were surveyed and analyzed to explore the microplastic pollution in the riverbed of the Loess Plateau. Microplastics were found in all sediment samples, with an abundance of 208.89–686.67 items kg−1. Polypropylene and polyethylene were the main microplastic components identified using Fourier transform infrared spectrometry and imaging systems. Particles 0.5–1.0 mm in size accounted for 38.5 % of the total microplastics in this region. The main microplastic colors were black, white, and transparent, which accounted for 40.75 %, 20.75 %, and 20.38 % of the total microplastics, respectively. There was an increasing trend in the microplastic abundance in sediments in the downstream direction that accompanied the increase in population density from 55.31 persons km−2 upstream to 230.05 persons km−2 downstream. Microplastic pollution was related to the complex geographical, semiarid monsoon climate, elevation, grassland, per capita GDP, and anthropogenic factors in the Yan River basin. The erodible loess and high-intensity rainstorm promoted severe soil erosion, which caused microplastics absorbed in the soil to migrate to the river. Poorly managed solid wastes, such as agricultural mulch, plastic bottles, and other plastic products are also sources of microplastics in the riverbed. This study further clarifies microplastic pollution in typical rivers of highly erosive areas and provides useful information for basin management.

Sediment pollution: An assessment of anthropogenic and geogenic trace element contributions along the central Algerian coast

Sediment cores from the central Algerian coast were collected to investigate the distribution, sources and risk of trace metals. The local geochemical background of metals was defined from the core S collected in an uncontaminated area of the coast. The anthropogenic inputs in Algiers Bay elevated Ag, Cd, Pb and Zn concentrations as their maximum were 3.1, 3, 2.1 and 1.8 times the background values, respectively. Meanwhile, increased contents of Arsenic (up to 21.1 mg/kg) were detected in all sites. Correlations and PCA suggest that lithogenic sources controlled metal deposition, while most sediment arsenic was agriculture-derived. Organic matter acted as a sink or source for some trace metals. According to EFs, the study area showed slight to moderate enrichment with respect to Ag, As, Pb, Cd, Zn and Cu, whereas they remained uncontaminated with Cr, V, Co and Ni. This study provides a needed baseline for future environmental investigations.

Removing Lead from Contaminated Sediment Using Indium-Based Perovskite Precursor.

Heavy metal pollution in river and lake sediments seriously damages river ecological safety and indirectly affects human health. The existing research mainly focuses on how to adsorb pollutants and repair sediment, and how the reuse of these pollutants may be a new technology to control sediment pollutants. The rapid development of perovskite solar cells in recent years has attracted a lot of attention, among which lead (Pb) halide perovskites have very excellent photoelectric performance. In this study, we propose a novel idea of introducing indium (In)-based perovskite to replace Pb (II) ions dispersed in river and lake sediment. Three sediment samples from a river in Shanghai Peace Park were collected to analyze the distribution of heavy metal Pb. We mixed the digestion solution of sediment with the prepared CH3NH3(MA)InICl2 solution and found that indium (In) in perovskite precursor solution would be gradually replaced by Pb in sediments. An in situ synchrotron radiation XRD experiment was performed to reveal the reaction mechanism of solutions and provide a good research platform for the comprehensive reuse of sediment in the future. This study provides a new method of remediation of heavy metal pollution in river and lake sediments.

Pollution sources and ecological risks of potentially toxic metals in sediments from a multi-functional Hsingda Harbor in southwestern Taiwan

Sediment metal pollution was assessed in a multi-functional harbor in southwestern Taiwan, Hsingda Harbor, which was developed from a traditional fishing port. Contamination level and ecological risks were identified using multiple sediment pollution indices referenced from the total metal contents (Cu, Zn, Pb, Cr, Ni, Hg, and Ag) and their chemical partitioning factions. This study used local background, normalization with Fe content, and correlation with total organic carbon to differentiate between natural and anthropogenic sources. Results showed that fisheries-related activities and the nearby coal-fired power plant primarily contributed to potentially toxic metal pollution. Remarkably, Cu, Zn, Pb, Cr, and Hg contents in the sediments along the nearshore fishing port (77.7, 270, 50.4, 99.1, and 0.31 mg/kg) were up to 2.1–9.5 times higher the background site. Significant Cu and Pb enrichment (EF: 5.4–6.6) may be attributed to antifouling paints and coal ashes. The adjacent oyster farm sediments were enriched with Cu and Zn (EF: 2.5–4.5), potentially threatening the oyster quality and public health. Moderate–high and low ecological risks were obtained from the assessments of total metal contents (PERI: 116–340) and extractable fractions (GRI: 9.0–28.6), respectively. Using total metals and chemical partitioning data provides a better understanding of potential ecological risks in sediments. Our results provide valuable information for environmental pollution control and mitigation during harbor development and management.

Electric field-enhanced immobilization of Cd and Pb in contaminated river sediments

The immobilization of heavy metal pollutants in river and lake sediments is critical for environmental health and safety. In this study, combined electrokinetic and chemical immobilization were used to remediate Cd and Pb polluted river sediments. The effect of the concentrations of the immobilization reagents and the applied voltage were investigated. Immobilization ratios for Cd and Pb of 98.6% and 84.3%, respectively, was achieved at 7.5 V cm−1 using seven successive rounds of recycling of the immobilization solution of mixed 1.0 g L−1 CO32− and 3.0 g L−1 H2PO4− at the volume ratio of 1:9 with 100 mL immobilization solution to 100 g sediment. The enhancement effect of the electric field is mainly attributed to the increased contact between the immobilization reagents and the heavy metals due to electroosmosis. This study provides a new method for the treatment of heavy metal-polluted sediments.

Editorial: Soil and sediment pollution, processes and remediation, volume II

Editorial: Soil and sediment pollution, processes and remediation, volume II

Assessment and Spatiotemporal Variability of Heavy Metals Pollution in Water and Sediments of a Coastal Landscape at the Nile Delta

This study assessed the spatiotemporal variability and pollution grades of heavy metals in water and sediments of Bahr El-Baqar drain, Eastern Nile Delta, Egypt, by integration of geochemical analysis, metal pollution indices, correlation, and multivariate statistical analyses. Twenty samples of water and sediments were collected during 2018 and analyzed for heavy metal concentrations using ICP-OES. Heavy metal contents in the water samples followed the order: Fe > Zn > Al > Pb > Mn > Cu > Ni. The drain sediments were highly contaminated with heavy metals that followed the order: Fe > Al > Mn > V > Zn > Cu > Cr > Ba > Ni > Pb > As. Spatiotemporally, most metals in the drain sediments showed a decreasing trend from upstream (south) to downstream sites (north). Results of principal component analysis (PCA) supported those from the Pearson correlation between investigated heavy metals. In water, Mn, Ni, Pb, Zn, Cu, and Fe showed highly significant correlations. In sediments, Ba, Ni, Zn, Fe, Al, Mn, and V showed strong positive correlations indicating that these metals were derived from similar anthropogenic sources. The calculated metal pollution indices: enrichment factor (EF), contamination factor (CF), pollution load index (PLI), degree of contamination (DC), and index of geo-accumulation (Igeo) indicated high loadings of heavy metals in the drain sediments. EFs revealed low, moderate to significant enrichment, whereas CFs showed low, moderate, and considerable contamination. PLI indicated low, baseline, and progressive contamination, while DC indicated low, moderate, and considerable degree of contamination. Igeo of all investigated metals (except for As; class 1) indicated extremely contaminated sediments (class 7).

Techniques for monitoring bioavailable organic pollutants in sediment: Application of poly(methyl methacrylate) as a passive sampler

A poly(methyl methacrylate) (PMMA) passive sampler was applied to harbor sediment to examine whether the substrate could be used as a tool to measure freely dissolved concentrations of contaminants. An ex situ method required at least 1g of PMMA to detect freely dissolved polycyclic aromatic hydrocarbons (PAHs) in sediment with <100ng/g dry weight. Two weeks were sufficient to reach equilibrium under 180rpm for PAHs with a molar volume of <250cm3/mol. For the in situ method, a deployment time of four months was sufficient to measure PAHs with a molar volume up to 250cm3/mol in the sediment bed. The PMMA passive sampler could be used to measure the bioavailable fraction of PAHs in porewater, reflecting the complex properties of sediment with strong sorption such as black carbons.

Heavy metals in coastal soils and sediments of the ponds in Samara

The total contents of Mn, Cr, Ni, Cu, Zn, Pb and Cd in foreshore soils and bottom sediments of 20 ponds have been investigated for the first time in Samara by the method of spectrometry with inductively coupled plasma. It is shown that polymetallic pollution of coastal soils and bottom sediments of 16 ponds out of 20 considered is acceptable; 3 ponds, located in the 13th microdistrict (small pond) and on the Solnechnaya street (large and small ponds), are characterized by moderately hazardous pollution with heavy metals; 1 pond, located in the area of the former Hippodrome, has a high level of pollution of coastal soils. Cu, Zn and Pb should be considered to be the main elements that significantly affected the ecological state of coastal soils and bottom sediments of the studied ponds. Their content in selected samples ranged: from 0,3 to 20,3 for Cu, from 0,2 to 14,9 units for Zn, from 0,2 to 25,2 units of background concentrations to Pb. The analysis of heavy metals average levels in coastal soils and bottom sediments of Samara ponds showed, that bottom sediments were enriched with all analyzed metals except Mn in comparison with coastal soils, whereas Mn was accumulated to upper levels in coastal soils. The location of water bodies in various parts of the urban area relief caused differences between the levels of heavy metals accumulation. For instance, the coastal soils of the ponds located on the watershed between the Saratov reservoir and the Samara River accumulated heavy metals more actively than the coastal soils of the ponds on the Volga slope. The accumulation of heavy metals in bottom sediments on the watershed was more active for Mn, Cr, Zn and Cd whereas in the ponds on the Volga slope it was shown for Ni, Cu and Pb.

Monitoring of Benzo(a)pyrene Pollution of Bottom Sediments of the Lake Baikal in the Sites of Increased Anthropogenic Load over the Period from 2011 to 2021

Monitoring of Benzo(a)pyrene Pollution of Bottom Sediments of the Lake Baikal in the Sites of Increased Anthropogenic Load over the Period from 2011 to 2021

Trace metals and polycyclic aromatic hydrocarbons in the Eastern Mediterranean sediments: Concentration ranges as a tool for quality control of large data collections.

Assessing the status of marine pollution at regional and sub-regional scales requires the use of comparable and harmonized data provided by multiple institutions, located in several countries. Standardized data management and quality control are crucial for supporting a coherent evaluation of marine pollution. Taking the Eastern Mediterranean Sea as a case study, we propose an approach to improve the quality control procedures used for sediment pollution data, thus supporting a harmonized environmental assessment. The regional ranges of contaminant concentrations in sediments were identified based on an in-depth literature review, and the lowest measured concentrations were evaluated to determine the "background concentrations" of chemical substances not yet targeted in the Mediterranean Sea. In addition, to verify the suitability of the approach for validating large data collections provided by multiple sources, the determined ranges were used to validate a regional dataset available through EMODnet data infrastructure.

Assessment of trace element pollution in Meyqan wetland sediments

Assessment of trace element pollution in Meyqan wetland sediments

Distribution, source finding, ecological hazard assessment, and water-sediment exchange rate of polychlorinated biphenyl (PCB) congeners in South Pars Industrial Zone, Iran.

South Pars Industrial Zone is located near an Assaluyeh city on the coast of the Persian Gulf and is known as the energy capital of Iran. In this study, environmental and health effects due to PCB congeners had an assessment. In this study, 10 air stations, 10 seawater, and sediments stations were systematically selected and sampled in two seasons. Air, seawater, and sediment pollution made by polychlorinated biphenyls (PCBs) were evaluated. Seawater-sediment exchange conditions using the fugacity coefficient reviewed. PCB levels in marine sediments, seawater, and air based on the analysis of the obtained data were 107.33-172.92ng/g, ND-135.68ng/L, and ND-4.4ng/m3, respectively. The highest concentration was observed in the vicinity of refineries, petrochemicals, and petroleum export facilities. These values had increased significantly compared to values of studies, conducted in similar areas. The sources were electrical wastes, storage sites, power generation units, and wastewater treatment. The ecological risk of seawater was assessed to be low to high, while sediment risks were reported with a low to moderate risk range. In 70% of the stations, the predominant transfer was from sediments to seawater; sediments were in fact the secondary source of seawater pollution. It is suggested for the area to be continuously monitored, while engineering and management measures should be adopted to improve the situation and also prevent the spread of pollution.

The environmental pollution of stream sediment in Ulutaş (Erzurum), Turkey

The environmental pollution of stream sediment in Ulutaş (Erzurum), Turkey

Assessment of trace metal pollution in the coastal sediments of Fethiye-Göcek Bay (SW Turkey) and evaluation of pollution sources

This research evaluated the trace metal pollution and the pollution sources in the coastal sediments of Fethiye-Göcek Bay by using the spatial distribution maps, correlation and statistical analysis, which were acquired from 69 sampling points. Spatial distribution maps for eleven elements (namely Al, As, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Ti, V, and Zn) revealed that there is an enrichment of the studied elements, especially near Fethiye harbor. Moreover, the contamination evaluation carried out by using different evaluation methods suggests considerable contamination of As, Co, Cr and Ni. There is a high correlation between Ni, Co, and Fe, Even the minimum Ni concentrations are 9 fold enriched relative to the Earth Crust's values. The controlling factors for element distribution in the area are both natural and anthropogenic. The natural sources are related to the weathering of the geological units and hydrothermal activity. In contrast, various anthropogenic sources include coal smoke, fuel oils used near the crowded harbors, urbanization and the increase in the population recently. When the ecological risk of these enriched elements is considered, the level of probability of toxicity comes out to be the highest, which demonstrates that the accumulation of trace metals in harbor sediments should be considered in the near future to prevent any contamination toward biota and human.

Environmental and Human Risk Assessment of Radioactive Pollution in Sediments of Northern Nile Delta, Egypt

ABSTRACT To evaluate radiation risks and the exposure to human and marine life, samples of marine sediments were taken along Mediterranean Sea Coastline and Lake Burullus, Egypt. The current study sought to evaluate the levels of 226Ra, 238U, 232Th and 40K radioactive elements in surface sediments as well as their ecological concerns and potential sources using remote sensing and GIS. The multivariate statistical analyses were done to assume the inter-relationships between the radiological indexes and concentrations. The activity of radionuclides concentrations in sediments for 226Ra, 238U, 232Th and 40K were 13.81, 9.08, 15.28 and 155.48 Bq/kg, and 7.29, 5.84, 8.2 and 136.98 Bq/Kg for Lake Burullus and Sea, respectively. It is obvious that radionuclides concentrations are more in the lake than those of the sea, due to the nature of geological and tectonic structures of the lake. The activity concentration of 226Ra didn’t exceed the world averages recorded by UNSCEAR but 40K value exceeded this limit twice. The higher levels of 226Ra were due to anthropogenic activities, Soil type and geological components which may influence the concentrations of the radionuclides. The multivariate analyses showed different trends to site 3 than other sites and different trend to 40K than other radionuclides. Partial least squares regression (PLS) analysis indicated decrease in the elements in the area of Lake Burullus and increase in the coastline of Mediterranean Sea. With the exception of 40k, all results indicated that radioactive pollution is safe and may not pose threat to human or the environment. Nevertheless, it is advised to apply cost–benefit analysis to maximize radiation protection.

The seasonal assessment of heavy metals pollution in water, sediments, and fish of grey mullet, red seabream, and sardine from the Mediterranean coast, Damietta, North Egypt

The current study investigated the deposit of heavy metals, including copper (Cu), zinc (Zn), cadmium (Cd), manganese (Mn), lead (Pb), chromium (Cr), and iron (Fe) in grey mullet (Mugil cephalus), red seabream (Pagrus pagrus), and sardine (Sardinella aruita) over winter and spring seasons 2022 at the Damietta port, a marine port constructed in 1982 on the north coast of Egypt, and the surrounding region. Water, sediment, and fish samples were collected from four sites near Damietta port throughout the spring and winter of 2022 to evaluate the amount of heavy metal in water, sediment, muscles, and fish liver. Heavy metal concentrations significantly differed across organs; however, their levels in liver tissues exceeded those in muscle tissues. It was noted that M. cephalus had the highest concentrations of heavy metals compared with other fish species. Heavy metals accumulation in fish organs was in the following order: Fe > Zn > Mn > Pb >Cu > Ni > Cd > Cr. During winter season, metals levels in water samples were in the following sequence: Fe > Ni > Zn > Cd > Cr > Pb > Cu > Mn, meanwhile in spring season, the order was as follows: Ni > Pb > Fe > Cr > Zn > Cd > Cu > Mn. During the winter time, the order of metals levels in sediment samples was Zn > Fe > Mn > Cu > Pb > Ni > Cd > Cr, but in the springtime, it was Zn > Fe > Mn > Cu > Ni > Pb > Cd > Cr. Finally, the human risk assessment concluded that grey mullet, red seabream, and sardine in Damietta port and neighboring regions are safe for human feeding and that various wastes may be disposed of securely, avoiding the buildup of heavy metals.

Sediment and interstitial water heavy metals in mangrove restoration wetland and preliminary exploration of microplastics in interstitial water

Compared with heavy metals in sediments, those in interstitial water can act as better indicators of bioavailability. Based on different planting densities, the distribution and risk of heavy metals (Zn, Cu, Ni, Cd) in the sediments and interstitial waters of “Kandelia obovata - Rhizophora stylosa - Bruguiera gymnorhiza” in a mangrove wetland restoration were studied, and the identification and analysis of microplastics in interstitial water were preliminarily explored. The results showed that the spatial distribution of heavy metals in sediments and interstitial waters in mangrove restoration wetlands varied greatly and was primarily affected by planting density and sediment properties. The geo-accumulation index, potential ecological risk index of a single trace metal, and comprehensive potential ecological risk index indicated that the level of Cd pollution in sediments was high. The results of the interstitial water criteria toxicity unit (IWCTU) and Nemerow index (NI) showed that the pollution level of heavy metals in interstitial water was generally high. Among them, the IWCTU values of Cu and Zn were>1, whereas the average value of the NI reached 2.67, which exerted adverse effects on the survival and growth of environmental organisms. In addition, the types and abundance distribution characteristics of microplastics in the interstitial waters of mangrove restoration wetlands were explored. The abundance of microplastics in the interstitial waters of the entire study area was 306.7–553.3 L-1. Moreover, different planting densities of mangroves could substantially affect the abundance distribution of microplastics, and the maximum value appeared when the planting density was 0.5 × 0.5 m. Polyethylene (49 %), polypropylene (21 %) and polyethylene terephthalate (11 %) were the most common and main microplastics in interstitial water. Scanning electron microscopy/energy-dispersive X-ray spectroscopy analysis showed that interstitial water microplastics had characteristics similar to those of sediment microplastics, such as fracture, tear, sag, and material adhesion, and the surface of the interstitial water microplastics could absorb a large amount of metal elements.

Distribution pattern and ecological risk assessment of heavy metals and PAHs in sediments of the entrance of Musa estuary, Persian Gulf to establish desalination plant

Musa estuary is a critical channel in northwest of Persian Gulf. The aim of present study was to assess the distribution pattern and ecological risk of heavy metals and PAHs in sediments of this estuary to evaluate the possibility of the establishment of desalination plant in this area. To this end, polycyclic aromatic hydrocarbon (PAH) and heavy metal pollution in surface sediments of Musa estuary from 12 stations was evaluated, and the potential sources of pollution and their ecological risks were investigated. The conductivity, temperature, and depth data from the sampling area were also reported. Twenty-two metals including aluminum (Al), Magnesium (Mg), Iron (Fe), Titanium (Ti), Manganese (Mn), Barium (Ba), Chromium (Cr), Vanadium (V), Nickel (Ni), Zirconium (Zr), Zinc (Zn), Copper (Cu), Lead (Pb), Arsenic (As), Cobalt (Co), Uranium (U), Caesium (Cs), Molybdenum (Mo), Beryllium (Be), Tin (Sn), Cadmium (Cd), and Thallium (Tl) were analyzed using Inductively Coupled Plasma Mass Spectrophotometer (ICP-MS), and PAHs were determined by GC/MS instrument. Results indicated that most of the stations were moderately polluted regarding Cr and Ni. Average concentrations of As, Cr, and Ni in most of sediments were higher than their threshold effect levels throughout sampling area. Enrichment factor based on average element levels demonstrated that elements in studied area originated from natural sources. In addition, results indicated low to moderate PAH pollution levels in sediment samples; the source of pollution was estimated to be pyrolitic. In general, results demonstrated that PAHs and heavy metals pose no threat regarding adverse biological effects, and the studied area has enough potential for accepting development projects related to desalination plants.

Elevated Urbanization-Driven Plant Accumulation of Metal(loid)s Including Arsenic Species and Assessment of the Kłodnica River Sediment Contamination

The impact of water and bottom sediment pollution of a river subjected to a strong industrial anthropogenic pressure of metal(loid) (including arsenic and its species) accumulation in riverbank plants such as Solidago virgaurea L., Phragmites L. and Urtica dioica L. was investigated. The high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) technique was used to study organic and inorganic arsenic species in selected plants and their response to heavy metal and arsenic contamination. The modified BCR extraction results showed that arsenic was mainly bound to the mobile reducible and organic-sulfide fractions in the Kłodnica River bottom sediments. Research has shown that the bottom sediments of the Kłodnica River are contaminated with metals, including Pb, Zn, Ni, As, and among arsenic species, the As(V) form dominated quantitatively, with its highest concentration being 49.3 mg kg−1 and the organic species occurred extremely rarely. The highest concentration of arsenic, among the tested plants, occurred in Phragmites communis L. The evaluation of the bottom sediment pollution was performed using Sb/As factor, geoaccumulation index (Igeo), enrichment factor (EF) and pollution load index (PLI). The ability of the plant to assimilate metals from the substrate was studied by calculation of the bioaccumulation factor (BAF). Values of the Igeo change in a wide range from class 1 (uncontaminated to moderately polluted for Cu and Zn) at the first sampling point, to 5 (highly to extremely polluted for Ba and Fe) at the K4 sampling point. The Igeo results show an increase in the contamination with elements toward the runoff of the Kłodnica River.