Determination of toxic elements in waters and sediments from River Subin in the Ashanti Region of Ghana

Using neutron activation to assess heavy metal pollution in water and sediment along Savannah River

A comprehensive study was conducted to assess heavy elemental pollution in the Savannah River, which flows through diverse landscapes encompassing agricultural, industrial, and commercial zones in South Carolina and Georgia. The investigation focused on the impacts of various anthropogenic activities on the river, potentially harming human health and aquatic ecosystems. Thirty samples, collected from the beginning of the Savannah River at Lake Hartwell to the Savannah River estuary near the Atlantic Ocean, were analyzed using Instrumental Neutron Activation Analysis. In regions of intense industrial activities, water samples exhibited elevated concentrations of elements such as Al (0.04-1.99 mg/L), Mg (0.4-5.5 mg/L), Ba (0.08-2.8 mg/L), Zn (0.017-0.9 mg/L), Cr (0.005-1.5 mg/L), and Fe (2.8-110.13 mg/L). Similarly, sediment samples near industrial areas also exhibited enhanced concentrations of heavy elements like Cr, Zr, Rb, Co, Zn, Mg, Mn, and Al. The outcome of this study has identified a spatial trend along the Savannah River, revealing major elements responsible for pollution that could disrupt the ecological environment and potentially impact human health.

A spatiotemporal study on contamination and bioaccumulation of heavy metals in sediment and cyprinid fish (Capoeta razii) from Telar River, Iran

The concentrations of heavy metals (Cr, Cd, Ni, and Pb) were investigated in sediment and cyprinid fish (Capoeta razii) from Telar River, Iran in spring, summer, and autumn. Mean concentration of metals in fish and sediment over the seasonal sampling was as follows: Cr > Ni > Pb > Cd. Metal deposition in sediment was higher than their bioaccumulation in fish tissue. Unlike sedimentary metals, the tissue-content of Pb and Cr varied seasonally. Enrichment Factor (EF) values of Cr and Ni showed partial enrichment, implicating the role of anthropogenic inputs, while Pb was derived from natural weathering. When considering Pollution Load Index (PLI), an uneven temporal and spatial distribution of contamination was observed in sediment with moderate contamination level in spring and summer and no pollution in autumn. Tissue-contents of Pb, Cr, and Cd were below permissible limits while a higher risk level of Ni was noted for human consumption.

Eco-toxic risk assessment and source distribution of trace metals in surface sediments of the coastal and in four rivers estuary of Sarawak

Background

Trace metals pollution in the coastal and estuarine sediment could harm water quality and aquatic organisms, leading to potential long-term health risks on the environment and humans. Thus, the purpose of this study was to conduct an assessment of selected trace metals in surface sediments of the coastal and in four rivers estuary in the Sarawak State of Malaysia to investigate their distribution, environmental risk, and potential source distribution.

Results

Average concentrations of trace metals in sediment increased in the following order: Cd ˂ As ˂ Co ˂ Cu ˂ Ni ˂ Cr ˂ Zn ˂ Mn ˂ Mg ˂ Fe. The enrichment, contamination, and geo-accumulation index results showed that surface sediments were polluted with Zn and Mg. In contrast, the other metals (i.e., As, Fe, Mn, Ni, Cr, Cu, Co, and Cd) indicated background concentration to minor contamination. Generally, the pollution load index values showed that almost all the sampling sites were unpolluted with the selected trace metals. Sediment quality guidelines (SQGs) and risk indexes were employed to assess the ecotoxicological risk of trace metal contamination in the sediments. The results proved that studied trace metals are not likely to have a deleterious impact on bottom-dwelling organisms. Still, a further accumulation of trace metals such as Zn, Ni, and Cr with time may adversely affect bottom-dwelling organisms. The risk index results showed a low ecological risk to the study sites. The correlation analysis and principal component analysis indicated that nine studied trace metals have strong interrelationships, suggesting common pollution sources or similar geochemical characteristics.

Conclusions

The study highlights the need to make tremendous efforts to monitor and control trace metal pollution in the coastal and estuarine areas.

The concentration of potentially hazardous elements (PHEs) in drinking water and non-carcinogenic risk assessment: A case study in Bandar Abbas, Iran

In this study, concentration of potentially hazardous elements (PHEs) including slice (Si), strontium (Sr), aluminum (Al), Fluoride (F), Iron (Fe), Zinc (Zn), Barium (Ba), Lead (Pb), Lithium (Li), Vanadium (V), selenium (Se), Chrome (Cr), Arsenic (As) and Uranium (U) in tap drinking water (n = 40) and filtration plant (n = 22) in Bandar Abbas city between March to July 2020 were analyzed. Analysis of PHEs ions was conducted by inductively coupled plasma mass spectrometry (ICP-MS). Also, concentration of F was measured by SPADNS Method. The non-carcinogenic risk in the exposed population (adult and children) were estimated. Concentration of PHEs between tap drinking water and filtration plant was compared using T statistical test. In addition, association among PHEs in tap drinking water and water filtration plant using Pearson correlation coefficient. The rank order of PHEs in tap drinking water was Si (6356.25 μg/l) > Sr (3980 μg/l) > Al (115.42 μg/l) > Fe (30.00 μg/l) > Zn (14.59 μg/l) > Ba (13.91 μg/l) > Pb (13.01 μg/l) > Li (11.60 μg/l) > V (4.43 μg/l) > Se (4.17 μg/l) > Cr (2.51 μg/l) > As (2.00 μg/l) > U (0.65 μg/l) > F (0.31 μg/l) and also in filtration plant was Si (1825.00 μg/l) > Sr (539.00 μg/l) > Fe (45.00 μg/l) > Al (26.00 μg/l) > Zn (8.08 μg/l) > Ba (2.24 μg/l) > Se (1.36 μg/l)> Pb(1.28 μg/l) > Li (1.26 μg/l) > Cr (1.17 μg/l) > F (0.66 μg/l) > V (0.61 μg/l) > As (LOD < ) ~ U (LOD <). The most of PHEs in tap drinking water was considerable different with filtration plant (p value < 0.05) therefore the chemical quality of tap drinking water should be more attention. The results of non-carcinogenic risk assessment revealed that TTHQ in the adults and children due to drinking tap water content of PHEs was 2.59E-3 and 6.05E-3 and filtration plant was 8.88E-04 and 2.07E-03, respectively. Therefore, TTHQ in adults and children was lower than 1; therefore, consumers are in the safe range due to drinking tap water and water filtration plant content of PHEs.

Ionomic Approaches for Discovery of Novel Stress-Resilient Genes in Plants

Plants, being sessile, face an array of biotic and abiotic stresses in their lifespan that endanger their survival. Hence, optimized uptake of mineral nutrients creates potential new routes for enhancing plant health and stress resilience. Recently, minerals (both essential and non-essential) have been identified as key players in plant stress biology, owing to their multifaceted functions. However, a realistic understanding of the relationship between different ions and stresses is lacking. In this context, ionomics will provide new platforms for not only understanding the function of the plant ionome during stresses but also identifying the genes and regulatory pathways related to mineral accumulation, transportation, and involvement in different molecular mechanisms under normal or stress conditions. This article provides a general overview of ionomics and the integration of high-throughput ionomic approaches with other "omics" tools. Integrated omics analysis is highly suitable for identification of the genes for various traits that confer biotic and abiotic stress tolerance. Moreover, ionomics advances being used to identify loci using qualitative trait loci and genome-wide association analysis of element uptake and transport within plant tissues, as well as genetic variation within species, are discussed. Furthermore, recent developments in ionomics for the discovery of stress-tolerant genes in plants have also been addressed; these can be used to produce more robust crops with a high nutritional value for sustainable agriculture.

Distribution and potential ecological risk assessment of trace elements in the stream water and sediments from Lanmuchang area, southwest Guizhou, China

Trace elements contamination in sediment is regarded as the global crisis with a large share in developing countries like China. Water and sediment samples were collected during (2016) from Qingshui Stream and analyzed for major physicochemical properties and trace elements by using ICP-MS. Our result of sediments showed that studied trace elements (except Pb, Cd, Co) had a concentration higher than Chinese sediment guideline as well as stream water data for studied trace elements (except Cr, Pb, Cd, Cu, and Zn) had a higher concentration than the maximum permissible safe limit of WHO. Contamination factor (CF) confirmed a moderate to high contamination in the sediment samples due to As and Tl, respectively. The values of pollution load index (PLI) were found above one (> 1), describing the progressive sediment quality decline. Pearson correlation showed that there was a significant positive association between Tl and As (r = 0.725, p < 0.05) in sediment samples. Results revealed that water-rock interaction, weathering of Tl sulfide mineralization, and hydrogeological conditions were major sources of stream water and sediments contamination in the study area. This experimental study contributes to a better understanding of the geochemistry and prevention of trace element contamination in sediments from Lanmuchang area.

Distribution, enrichment, and source identification of selected heavy metals in surface sediments of the Siran River, Mansehra, Pakistan

To assess the trace metal pollution in the Siran River, sediments were collected from 12 sites, from the left and right banks of the river in 2013. The concentrations, accumulation, distribution pattern, and pollution status of heavy metals in sediments were investigated using geoaccumulation index (I geo) and enrichment factor (EF). The toxic risk of heavy metals was assessed using interim sediment quality guidelines (ISQGs), portable effect level (PEL), threshold effect level (TEL), and toxic effect threshold (TET). I geo and EF values showed that sediments were loaded with Ni, Cd, Pb, and Co and no obvious variations were found among the left and right banks of the river. The EF and I geo values were found in order of Co > Pb > Ni > As > Cd > Cu > Zn > Fe and Cd > Co > Pb > Ni > As > Fe > Zn > Cu > Mn, respectively. Furthermore, multivariate statistical analysis like inter-metal correlation, cluster analysis (CA), and principal component analysis (PCA) results revealed that geogenic and anthropogenic activities were major sources of sediment contamination in the study area. These results indicated that more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution.

Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana-Part 2: Natural Sciences Review

This paper is one of three synthesis documents produced via an integrated assessment (IA) that aims to increase understanding of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities surrounding ASGM, an integrated assessment (IA) framework was utilized to analyze socio-economic, health, and environmental data, and co-develop evidence-based responses with stakeholders. This paper focuses on the causes, status, trends, and consequences of ecological issues related to ASGM activity in Ghana. It reviews dozens of studies and thousands of samples to document evidence of heavy metals contamination in ecological media across Ghana. Soil and water mercury concentrations were generally lower than guideline values, but sediment mercury concentrations surpassed guideline values in 64% of samples. Arsenic, cadmium, and lead exceeded guideline values in 67%, 17%, and 24% of water samples, respectively. Other water quality parameters near ASGM sites show impairment, with some samples exceeding guidelines for acidity, turbidity, and nitrates. Additional ASGM-related stressors on environmental quality and ecosystem services include deforestation, land degradation, biodiversity loss, legacy contamination, and potential linkages to climate change. Though more research is needed to further elucidate the long-term impacts of ASGM on the environment, the plausible consequences of ecological damages should guide policies and actions to address the unique challenges posed by ASGM.

A Systematic Review of Heavy Metals of Anthropogenic Origin in Environmental Media and Biota in the Context of Gold Mining in Ghana

Heavy metal accumulation in the food chain is an issue of global concern because it eventually leads to toxic effects on humans through the water we drink, contaminated soils, crops, and animals. Reports of toxicant levels in environmental media (air, water, and soil) and biota in Ghana were sought in SCOPUS, PubMed, MEDLINE, and EMBASE. Of 1004 bibliographic records identified, 54 studies were included in evidence synthesis. A disproportionately large number of papers (about 80%) focused exclusively on environmental media. Papers focusing on biomonitoring and human health were relatively few. Studies reported a high degree of spatial variability for the concentrations of 8 metals in groundwater. Generally, heavy metal concentrations in soil reported by the studies reviewed were higher than metal concentrations in riverine sediments. Urine and hair were the most common biological markers of heavy metal exposure used by the studies reviewed unlike nails, which were sparingly used. By and large, published results on the levels of heavy metals in goldmine and non-mine workers yielded contradictory results. Mostly, concentrations of heavy metals reported by the studies reviewed for nails were higher than for hair. A high degree of variability in the heavy metal concentrations in human subjects in the studies reviewed is likely due to heterogeneity in physiological states, excretion profiles, and body burdens of individuals. These, in turn, may be a product of genetic polymorphisms influencing detoxification efficiency.

Cadmium-induced oxidative stress tolerance in cadmium resistant Aspergillus foetidus: its possible role in cadmium bioremediation

Toxic effects of cadmium (Cd) were examined on a cadmium-resistant strain of Aspergillus foetidus isolated from wastewater. The Cd removal potential was analyzed. The results indicated that the strain could tolerate up to 25 mM and 63 mM Cd in liquid and solid Czapek-Dox media, respectively. It efficiently removed Cd from liquid growth media and industrial wastewater by mycelial biosorption. The strain produced oxalic acid for the purpose of Cd bioleaching as confirmed by the presence of cadmium oxalate crystals on the mycelial surface. Intracellular proline contents and the antioxidative enzyme activities increased up to a certain level to detoxify the overproduced free radicals. These data indicate that the strain has inherent mechanisms to grow in Cd contaminated environment, tolerate high Cd doses and high Cd uptake potential which are pre-requisite for acting as a suitable candidate for Cd bioremediation.

Enrichment and geo-accumulation of heavy metals and risk assessment of sediments of the Kurang Nallah--feeding tributary of the Rawal Lake Reservoir, Pakistan

Heavy metal concentrations in sediments of the Kurang stream: a principal feeding tributary of the Rawal Lake Reservoir were investigated using enrichment factor (EF), geoaccumulation index (Igeo) and metal pollution index (MPI) to determine metal accumulation, distribution and its pollution status. Sediment samples were collected from twenty one sites during two year monitoring in pre- and post-monsoon seasons (2007-2008). Heavy metal toxicity risk was assessed using Sediment Quality Guidelines (SQGs), effect range low/effect range median values (ERL/ERM), and threshold effect level/probable effect level (TEL/PEL). Greater mean concentrations of Ni, Mn and Pb were recorded in post-monsoon season whereas metal accumulation pattern in pre-monsoon season followed the order: Zn>Mn>Ni>Cr>Co>Cd>Pb>Cu>Li. Enrichment factor (EF) and geoaccumulation (Igeo) values showed that sediments were loaded with Cd, Zn, Ni and Mn. Comparison with uncontaminated background values showed higher concentrations of Cd, Zn and Ni than respective average shale values. Concentrations of Ni and Zn were above ERL values; however, Ni concentration exceeded the ERM values. Sediment contamination was attributed to anthropogenic and natural processes. The results can be used for effective management of fresh water hilly streams of Pakistan.

Distribution and source analysis of aluminum in rivers near Xi'an City, China

To study the status and source of aluminum (Al) contamination, a total of 21 sampling sites along six rivers near Xi'an City (Shaanxi province, China) were investigated during 2008-2010. The results indicated that the average concentration of total Al (Al(t)) in the six rivers increased by 1.6 times from 2008 to 2010. The spatial distribution of Al(t) concentrations in the rivers near Xi'an City was significantly different, ranged from 367 μg/L (Bahe River) to 1,978 μg/L (Taiping River). The Al(t) concentration was highest near an industrial area for pulp and paper-making (2,773 μg/L), where the Al level greatly exceeded the water quality criteria of both the USA (Criterion Continuous Concentration, 87 μg/L) and Canada (100 μg/L). The average concentration of inorganic monometric aluminum (Al(im)) was 72 μg/L which would pose threats to fishes and other aquatic lives in the rivers. The concentrations of exchangeable Al (Al(ex)) in the sediment of the Taiping River sampled were relatively high, making it to be an alternative explanation of increasing Al concentrations in the rivers near Xi'an City. Furthermore, an increasing Al level has been detected in the upstream watershed near Xi'an City in recent years, which might indicate another notable pollution source of Al.

Water quality associated public health risk in Bo, Sierra Leone

Human health depends on reliable access to safe drinking water, but in many developing countries only a limited number of wells and boreholes are available. Many of these water resources are contaminated with biological or chemical pollutants. The goal of this study was to examine water access and quality in urban Bo, Sierra Leone. A health census and community mapping project in one neighborhood in Bo identified the 36 water sources used by the community. A water sample was taken from each water source and tested for a variety of microbiological and physicochemical substances. Only 38.9% of the water sources met World Health Organization (WHO) microbial safety requirements based on fecal coliform levels. Physiochemical analysis indicated that the majority (91.7%) of the water sources met the requirements set by the WHO. In combination, 25% of these water resources met safe drinking water criteria. No variables associated with wells were statistically significant predictors of contamination. This study indicated that fecal contamination is the greatest health risk associated with drinking water. There is a need to raise hygiene awareness and implement inexpensive methods to reduce fecal contamination and improve drinking water safety in Bo, Sierra Leone.

Statistical evaluation of environmental contamination, distribution and source assessment of heavy metals (aluminum, arsenic, cadmium, and mercury) in some lagoons and an estuary along the coastal belt of Ghana

An environmental pollution investigation was carried out to determine the concentrations of aluminum (Al), arsenic (As), cadmium (Cd), and mercury (Hg) (heavy metals) in the surface water and river water bed sediments of lagoons and estuaries along the coastal belt of Ghana. The study assessed the environmental pollution situation and evaluated their sources and distribution of these metals. The total concentrations of Al, As, Cd, and Hg were determined by the neutron activation analysis technique. Water and sediment samples were collected from the Benya, Fosu, and Narkwa lagoons in the Central Region and from the Pra estuary in the western part of Ghana. Some indices, such as contamination factor, pollution-load index, contamination degree, and geoaccumulation index, were used to assess eco-environmental quality of the sampling sites. The analysis indicated that the Fosu lagoon was fairly polluted with Cd. The investigation indicated a highly localized distribution pattern closely associated with the two pollution sources (garbage/solid waste dumps and industrial activities) along the coastal belt. The resulting environmental deterioration required a concerted evaluative effort by all stakeholders.

Effect of agrochemical use on the drinking water quality of Agogo, a tomato growing community in Ashanti Akim, Ghana

The effect of agrochemical use in agricultural activities on the drinking water quality of ground and surface water within Agogo, a prominent tomato growing area in the Ashanti region of Ghana was assessed by monitoring physicochemical parameters, trace metals and microbial quality of two water sources. Levels of contamination were greater in surface water than groundwater. Trace metal levels (mg/L) were 1.40, 0.12, 0.08 and 0.18 in surface water and 0.08, 0.10, 0.05 and 0.08 in groundwater for Fe, Pb, Zn and Cd, respectively. Lead and Cd in surface and groundwater exceeded USEPA maximum acceptable levels (MCLs) for drinking water. Bacterial indicator numbers (geometric means/100 mL) in surface water varied from 9.35 x 10⁵ to 1.57 x 10¹¹ for total coliforms, 4.15 x 10⁴ to 2.10 x 10⁷ for faecal coliforms and 2.80 x 10 to 3.25 x 10² for enterococci, but none was found in groundwater.

Assessment of heavy metal concentration in the Khoshk River water and sediment, Shiraz, Southwest Iran

Heavy metal contents and contamination characteristics of the water and sediment of the Khoshk River, Shiraz, Southwest Iran were investigated. The abundance of heavy metals decreases as Zn > Mn > Cr > Ni >Pb > Cu > Cd in water samples and Mn > Cr > Pb > Ni > Zn > Cu > Cd in sediments, respectively. Based on the enrichment factor and geoaccumulation index values, sediments were loaded with Cr, Zn, Pb, Cu, and Cd. Pearson correlation matrix as well as cluster and principal components analyses and analysis of variance were implemented on data from sampling sites. Based on the locations of sampling sites in clusters and variable concentrations at these stations, it was concluded that municipal, industrial, and domestic discharges in the Shiraz urban area strongly affected heavy metals concentrations in the Khoshk River water and sediment. Results obtained from principal components analysis of sediment samples showed that the high concentration of Ni was mainly from natural origin, related to the composition of parent rocks, while the elevated values of Cr, Zn, Pb, Cd, and Cu were due to anthropogenic activities.

The relationship between trace elements in fish otoliths of wild carp and hydrochemical conditions

The trace element composition of the fish otolith is an indicator of biomineralization. In contrast to other skeletal tissue, the otolith retains its entire original structure and does not absorb any elements after the fish dies. Because otoliths in carp degrade very slowly in the dead body, the information it provides on the environment is retained, even in fossil form. Here, we report our analysis of the trace elements in otoliths of carp and of the water in Donghu Lake and Longhupao Lake, Heilongjiang province, China, where the fish lived. The results revealed that the trace elements found in the carp otoliths were clearly correlated with those found in these water bodies. There were high concentrations of Au, Ba, K, Sr and Zn in both the water and otoliths; in contrast there were high levels of As, Na and Se in water, but low concentrations in otoliths. These results indicate that an analysis of the otoliths of carps provides an accurate procedure for studying the surrounding hydrochemistry conditions. The interaction of the elements during deposition was also studied. The correlation coefficients of 13 trace elements identified in the otoliths in both lakes were calculated.