Bioaccumulation Of Heavy Metals Research Articles

Http://jeb.co.in./journal_issues/202311_nov23/paper_12.pdf

Aim: The aim of this research was to identify a suitable lichen species as a bio-indicator for heavy metals in the Himalayan habitats. Methodology: The study was conducted in a sacred grove located in Western Nepal. The grove was situated alongside the busy Mahakali National highway. Lichen samples were collected from different areas of the grove, ranging from the edge adjacent to the highway to the center. Standard protocols were employed to identify the collected lichen species. The heavy metal content in the samples were analyzed by subjecting them to acid digestion followed by AAS estimation. Results: Three lichen species were discovered: Bulbothrix meizospora, Parmotrema tinctorum, and Pyxine berteriana. Pyxine berteriana was collected near the highway, while Bulbothrix meizospora and Parmotrema tinctorum were collected away from it. The heavy metal bioaccumulation pattern observed was as follows: Fe>Al>Mg>Zn>Cu>Pb>Mn>Ni>Cd>Cr. Notably, Pyxine berteriana exhibited the highest metal concentrations among the three species. Interpretation: Based on the findings, it can be concluded that the Physcioid lichen Pyxine berteriana is the most resilient species in the region and can serve as an appropriate bio-indicator for studying the deposition of heavy metals in the ambient air. Key words: Physcioid lichens, Pyxine berteriana, Parmotrema tinctorum, Lichens, Sacred Grove

Bioaccumulation of Heavy Metals and Hydrocarbons in Sediment, Shell and Flesh of the Faunas in Qua-Iboe River at Ibeno, Akwa Ibom State, Nigeria

Bioaccumulation of Heavy Metals and Hydrocarbons in Sediment, Shell and Flesh of the Faunas in Qua-Iboe River at Ibeno, Akwa Ibom State, Nigeria was undertaken. The faunas and sediment sample were collected from designated locations and a control location along Ikot-Ibok in dry and wet seasons using standard analytical sampling methods. The samples were analyzed for heavy metals and hydrocarbons content by atomic absorption spectrophotometer and gas chromatography respectively. pH of the samples was assessed. Transfer factor (TF) of the heavy metals between the sediment and the faunas were calculated. Regression models (linear and power equation) were developed to predict the numerical relationship between total petroleum hydrocarbon and total hydrocarbon content (TPH and THC) and heavy metals concentration in shell (predictor) of fauna in relation to their concentration in the flesh (dependent). Results obtained were subjected to statistical analysis such as coefficient of variation and mean. The concentration range of the heavy metals of both faunas and sediment was 0.001 – 86. 686 mg/kg. These value are above the World Health Organization and National Environmental Standard and Regulations Enforcement Agency (WHO/NESREA) standards (0.001 -5.0mg/kg). The coefficient of variation (C.V) had a range of 0.0152 – 193.333% which showed variation in stability of the heavy metals. Transfer factor (TF) showed that Tympanotomus fuscatus tissue bioaccumulated most heavy metals. Hydrocarbons (TPH and THC) and heavy metals concentration in the flesh of Ostreidea and Tympanomus fuscatus tissue were predicted from its shells at highly significant level (P - ≤ 0.05). This study has provided information on the levels of heavy metals and Hydrocarbons in faunas and sediment. In addition, the study has also developed models for predicting the levels of heavy metals and hydrocarbon content in the flesh from the shell of the faunas studied.

Synergistic Interactions in Enzyme Activities During Vermiremediation of Heavy Metals (HMs) Polluted Soil: Elucidating the Impact of Eudrilus eugeniae

ABSTRACT The vermiremediation potential of Eudrilus eugeniae was assessed in heavy metals (HMs) contaminated soil in a microcosm experiment. In detail, efficacy of E. eugeniae was investigated in terms of reduction in HMs content, enhancement in the soil enzyme activities, synergistic correlation between the HMs and enzyme activities and bioaccumulation of HMs in the earthworm’s biomass. Moreover, a seed germination assay was also conducted to assess the HMs toxicity in soil after remediation. The results showed that Eudrilus eugeniae was capable of decreasing the Cu, Zn, Mn, Cr, and Ni contents in the soil by 17.56–26.30% after 90 days of experimental trial. Introduction of E. eugeniae increased cellulase, amylase, polyphenol oxidase, peroxidase, urease, dehydrogenase, and catalase activities by 30.3–80.95% compared to controls. Earthworm addition led to a 12.98% increase in G-Mean and 2.89% increase in T-QSI values, indicating significant soil health improvement. PCA revealed the negative impact of HMs on synergistic enzyme activities during vermiremediation. HMs content in earthworm biomass increased 13-fold. Seed germination assay confirmed HMs reduction by the end of the experiment. Thus, this study demonstrated the interconnected changes in the soil enzyme activities during vermiremediation of HMs from crude oil polluted soil.

Bioaccumulation and Mobility of Heavy Metals in the Soil-Plant System and Health Risk Assessment of Vegetables Irrigated by Wastewater

Accumulation of heavy metals in soil and vegetables is presently a challenging environmental concern worldwide. The present study was designed to elucidate heavy metals contamination of vegetables irrigated with domestic wastewater and associated health risks. The study area comprises three zones: Kot Addu, Alipur, and Muzaffargarh. A total of 153 samples of wastewater, topsoil, and vegetables were analyzed for physicochemical parameters and concentration levels of eight metal elements (Cu, Fe, Zn, Mn, Pb, Cd, Ni, and Cr) determined through analytical procedures. The outcome of the present investigation reveals that heavy metal concentrations in wastewater, soil, and vegetables irrigated with wastewater were slightly higher than the WHO-suggested limit. The heavy metals concentration observed in vegetables irrigated with wastewater can be ranked in order of Ni > Mn > Cr > Pb > Cu > Fe > Zn > Cd. Transfer factor (TF), daily ingestion of metals (DIM), and health risk index (HRI) were calculated. Spinach exhibited higher values of transfer factor than cabbage, cauliflower, and radish, which were followed by tinda and carrot. Minimum values of HRI were observed for Cr (0.0109) in almost all of the vegetables ingested by adults and children. Cabbage exhibited higher values of HRI for Pb (4.0656) in adults, followed by cadmium (HRI = 2.993). Minimum values of HRI were calculated for Cd (0.0115; child). Cauliflower exhibited higher values of HRI (5.2768) for Pb in children. Pb, HRI values (4.5902) were observed in adults living in Kot Addu. The results exhibited similar trends of HRI in adults and children living in Muzaffargarh and Alipur.

Biochemical responses of freshwater microalgae Chlorella sorokiniana to combined exposure of Zn(Ⅱ) and estrone with simultaneous pollutants removal

With the development of livestock industry, contaminants such as divalent zinc ions (Zn (Ⅱ)) and estrone are often simultaneously detected in livestock wastewater. Nevertheless, the combined toxicity of these two pollutants on microalgae is still unclear. Moreover, microalgae have the potential for biosorption and bioaccumulation of heavy metals and organic compounds. Thus, this study investigated the joint effects of Zn (Ⅱ) and estrone on microalgae Chlorella sorokiniana, in terms of growth, photosynthetic activity and biomolecules, as well as pollutants removal by algae. Interestingly, a low Zn (Ⅱ) concentration promoted C. sorokiniana growth and photosynthetic activity, while the high concentration experienced inhibition. As the increase of estrone concentration, chlorophyll a content increased continuously to resist the environmental stress. Concurrently, the secretion of extracellular polysaccharides and proteins by algae increased with exposure to Zn (Ⅱ) and estrone, reducing toxicity of pollutants to microalgae. Reactive oxygen species and superoxide dismutase activity increased as the increase of pollutant concentration after 96 h cultivation, but high pollutant concentrations resulted in damage of cells, as proved by increased MDA content. Additionally, C. sorokiniana displayed remarkable removal efficiency for Zn (Ⅱ) and estrone, reaching up to 86.14% and 84.96% respectively. The study provides insights into the biochemical responses of microalgae to pollutants and highlights the potential of microalgae in pollutants removal.

Assessment of heavy metals bioaccumulation in Silver Birch (Betula pendula Roth) from an AMD active, abandoned gold mine waste.

Acid mine drainage (AMD) is generally outlined as one of the largest environmental concerns, characterized by very low pH value of mine waste, heavy metals and high sulphate content. This extremely hostile environment reduces plant ability to develop and grow. Present study focuses on a silver birch (Betula pendula Roth), a pioneer species that grows on an extremely hostile gold mine waste, to investigate the bioaccumulation of rare metals (thallium (Tl) and indium (In)), as well as nine other more common heavy metals (bismuth (Bi), cadmium (Cd), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), silver (Ag) and zinc (Zn)), and to asses phytoextraction and phytostabilization potential of silver birch. Additionally, parameters determining AMD process and overall contamination (pH, electrical conductivity (EC), sulphates (SO42-), arsenic (As), iron (Fe), oxidation-reduction potential (ORP), turbidity, dissolved oxygen (DO), total dissolved solids (TDS), acidity, hardness, X-ray diffraction (XRD) and radioactivity) were determined in mine waste and drainage water samples. To assess the heavy metals bioaccumulation and mine waste status, statistical geochemical indices were determined: bioaccumulation factor (BCF), pollution load index (PLI), geochemical abundance index (GAI) and exposure index (EI). The results show that silver birch bioaccumulates the essential elements Cu, Ni, Mn and Zn, and the nonessential elements Tl (average BCF = 24.99), In (average BC = 23.01) and Pb (average BCF = 0.84). Investigated mine waste was enriched by Bi, Ag and Cd according to positive values of GAI index. Present research provides a novel insight into bioaccumulation of nonessential heavy metals in silver birches who grow on the extremely hostile mine waste, and they exhibit significant phytoremediation potential.

Estimating biomass of woody plants that grow in the different As-contaminated techno-soils in the ore-bearing provinces of Eastern Germany

Establishing the role of woody species as an instrument for heavy metal bioaccumulation is a relevant issue today in the context of the development of the phytoremediation system. The article presents the results of studies on the influence of different Arsenic (As) concentrations in soil on the development of aboveground biomass in Betula pendula Roth. and Populus tremula L. stands under conditions of reclamation plantings. The studies were conducted in 30 locations of birch and poplar tree plantations within the ore-producing regions of Saxony (Eastern Germany) in soil with different levels of As contamination. The highest As content was noted in the technosoil of the Davidschacht site, where the metalloid content was 229.3 times greater compared with a value in a conditionally uncontaminated area (Großschirma). The values of leaf area index and aboveground biomass obtained in field measurements were presented. The aboveground biomass values in the investigated plantations ranged from 189.9 ±10.16 to 201.8 ± 19.09 t/ha, and leaf area index values ranged from 1.74 ± 0.29 to 2.05 ± 0.16 m2/m2. Sentinel-2A multispectral images were processed for the construction of a map of the aboveground biomass distribution within the region under study. The values of the spectral indices for leaf area index were obtained with subsequent construction of the regression dependence of the aboveground biomass in the plantings on this indicator. The RMSE value for the developed model of the dependence of aboveground biomass on the leaf area index was 17.84 t/ha, which could be considered as satisfactory and can serve as a basis for practical application of the model developed. The inverse trend in relation to locations with different levels of soil contamination with As was determined for the aboveground biomass indicator. Within the region under study, the highest value of aboveground biomass in the stands was found for the area with the lowest As level. The results showed that the correlation coefficient between the highest of the optimal spectral indices, the leaf area index, and the aboveground biomass in B. pendula and P. tremula plantings was statistically significant and approached the value of 0.7. The results presented can become a theoretical basis for monitoring the accumulation of aboveground biomass of tree stands in areas with different levels of soil contamination with As. In perspective, the presented model of biomass estimation based on spectral technologies can serve as an application basis for rapid assessment of the growth and development parameters of forest stands in As-contaminated areas.

Bioaccumulation of heavy metals in water and organs of Tilapia brevimanus and Euthynnus alletteratus from a coaster water in southwestern Nigeria

The bioaccumulation of some heavy metals in coaster waters directly affects the ecosystem and human beings. Thus, the objectives of this study are to evaluate the interaction between fish and coastal water and assess the long-term implications of human consumption of some major organs obtained from Tilapia brevimanus and Euthynnus alletteratus. The study determined the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), and lead (Pb) in twenty coaster water samples collected from two points and in the muscle, gills, and intestine of ten pieces of Tilapia brevimanus and ten pieces of Euthynnus alletteratus using a Perkin Elmer Model 306 Atomic Absorption Spectrometer. Furthermore, the accumulation of these metals and the assessment of the long-term implications of human consumption of the designated organs of the two species types were performed. The statistical significance level of the obtained results was determined using the T-test analysis tool, which revealed that the distribution of the metals varies in different organs of the fish species. The levels of pollutants were higher in Tilapia brevimanus organs than in Euthynnus alletteratus. The contents of As, Cd, Cr, and Pb in the gills were higher than those in the muscle. Also, the metal pollution index in the organs followed the order of intestine > gills > muscle for both Tilapia brevimanus and Euthynnus alletteratus, posing serious health risks.

Microbial Strategies for Heavy Metal Removal from Industrial Wastewater

The contamination of industrial wastewater with heavy metals poses a severe environmental and public health concern. Traditional methods of heavy metal removal often prove costly and environmentally unsustainable. In this context, microbial strategies have emerged as a promising and eco-friendly approach for effective heavy metal remediation from industrial wastewater. Microorganisms, including bacteria, fungi, and algae, have developed various mechanisms to withstand and sequester heavy metals from their surroundings. This review explores the diverse microbial strategies employed in heavy metal removal, encompassing biosorption, bioaccumulation, bioprecipitation, and bioleaching. These strategies exploit microbial cell surfaces, extracellular polymeric substances, and intracellular compartments to immobilize, transform, or release heavy metals. Moreover, recent advancements in genetic engineering and biotechnology have enabled the development of tailored microbial strains with enhanced metal-removal capabilities. The application of these engineered microbes, as well as naturally occurring strains, in bioremediation processes is discussed. This review also delves into the factors influencing microbial metal removal efficiency, such as pH, temperature, metal concentration, and co-existing contaminants. Additionally, the potential drawbacks and limitations of microbial strategies, including biomass disposal and long-term performance, are addressed. As heavy metal pollution continues to be a pressing global issue, understanding and harnessing microbial strategies for heavy metal removal from industrial wastewater holds significant promise for sustainable and cost-effective remediation practices. Integrating microbial processes into existing treatment methods can offer innovative solutions to mitigate the environmental impact of heavy metal contamination, thereby safeguarding ecosystems and public health

Heavy metals in wetlands of southwestern India: from sediments through invertebrates to migratory shorebirds

Heavy metal pollution in Indian wetlands is rising due to industrial, agricultural and urban development activities. Shorebirds occupy upper trophic levels and are therefore especially vulnerable to heavy metal pollution. We evaluated the concentration of heavy metals (zinc, copper, cobalt, chromium, lead and cadmium) in 22 common species of migrant shorebirds (220 shorebird dropping samples) with diverse foraging behaviors, in their different prey (55 prey samples) and in the sediments (90 sediment samples) in different habitat types (mudflats, mangroves and sand beaches) between 2019 and 2021. Further, we analyzed a total of 10 biofilm samples from mudflats and mangroves. We detected relatively low concentrations of heavy metals in the sediments (Zn concentration range: 9.11–40.91 mg/kg; Cu: 5.74–21.38 mg/kg; Co: 2.00–4.04 mg/kg; Cr: 4.05–41.03 mg/kg; Pb: 1.02–7.19 mg/kg; Cd: 0.56–4.35 mg/kg). However, we measured relatively high concentrations of heavy metals in invertebrate prey species (Zn concentration range: 84.72–224.74 mg/kg; Cu: 26.63–170.36 mg/kg; Co: 13.98–14.42 mg/kg; Cr: 14.78–98.16 mg/kg; Pb: 18.95–157.29 mg/kg; Cd: 9.33–60.56 mg/kg). In addition, we found high concentrations of heavy metals in shorebird droppings (Zn concentration range: 41.33–58.8 mg/kg; Cu: 31.42–52.11 mg/kg; Co: 36.34–55.68 mg/kg; Cr: 52.3–68.21 mg/kg; Pb: 25.94–43.13 mg/kg; Cd: 5.53–16.4 mg/kg). It is evident that concentration of heavy metals increased successively moving from sediment to prey to shorebird species, likely through trophic transfer. The biofilm samples contained very high concentrations of Cr, Pb and Cd (22.64, 28.09 and 18.46 mg/kg respectively) which could be harmful to biofilm grazing shorebirds. Since bioaccumulation of heavy metals entail risks in living species, we suggest that increasing concentrations may detrimentally affect physiological processes in invertebrates and shorebirds. There is an urgent need to identify the sources of pollution and to reduce the discharge of heavy metals and other pollutants into coastal and inland wetlands.

Analyzing Cadmium and Nickel Levels in Labeo Rohita, Catla Catla, and Cirrihinus Mrigala From Local Fish Markets in Lahore, Pakistan

Thirty-six (36) fish samples were collected from the different local fish markets of Lahore city to check the bioaccumulation of heavy metals. The mean Cd concentration ranged from (32.33 – 39.69ug/kg), (23.26 – 35.45ug/kg), (35.37 -45.06ug/kg) in gills (28.99- 38.17ug/kg), (21.74– 30.07ug/kg), (33.92 – 43.61ug/kg) in muscles (26.12– 35.56ug/kg), (18,87– 31.32ug/kg), (31.05 – 41.01ug/kg) in liver of Labeo rohita, Catla catla and Cirrihinus mrigala respectively. The mean Ni concentration ranged from (44.93 – 52.86ug/kg), (45.65 – 52.86ug/kg), (52.30 -61.14ug/kg) in gills (43.48- 51.41ug/kg), (44.20– 54.62ug/kg), (50.86 – 59.69ug/kg) in muscles (40.48 – 48.81ug/kg), (41.56 – 48.81ug/kg), (48.21 – 57.08ug/kg) in liver of Labeo rohita, Catla catla and Cirrihinus mrigala respectively. The comparison between sampling markets revealed no significant difference among them and the results between fish species shows highest concentration of Ni (55.26ppb) in Cirrhina mrigala. The accumulation pattern of all the heavy metals in different organs of all the studied fish species was significantly lower (p<0.05) as compared to admissible concentration reported by WHO. Therefore, the fish of these areas do not pose serious threat to human health upon consumption.

Lichen diversity and bioaccumulation of heavy metals in northern Tunisia: a study to evaluate environmental pollution

Lichen diversity and bioaccumulation of heavy metals in northern Tunisia: a study to evaluate environmental pollution

Health Risk Assessment of Heavy Metals in Imported Frozen Fish Sold in ‎Damaturu and Maiduguri Fish Markets, Nigeria

Heavy metals bioaccumulation in fish constitute an issue of public health concerns. This study aimed to evaluate the levels of Cadmium (Cd) and Lead (Pb) in the head and muscle tissues of imported frozen fish as well as health risk to man. A total of 30 frozen fish were sampled from different fish markets in Damaturu and Maiduguri in Yobe and Borno States, Nigeria respectively. Heavy metal concentrations were determined by atomic absorption spectrophotometer. The highest mean concentration levels (0.60 ± 0.32 mg/kg and 0.06 ± 0.10 mg/kg) of Pb and Cd were found in the head and the lowest (0.09 ± 0.02 and 0.01 ± 0.00) in the muscle tissues respectively. The mean concentration levels of Pb (0.60 ± 0.32 mg/kg) and Cd (0.06 ± 0.10 mg/kg) in fish markets A and D exceed the maximum allowable limits of 0.50 mg/kg and 0.05 mg/kg respectively. Fish markets had statistically significant (p< 0.05) effect on the concentration levels of Pb among the sampled fish. The assessment of potential health risk; estimated daily intake, the target cancer rate, target hazard quotient and hazard index values obtained were below the threshold, indicating consumption of head and muscle of imported frozen fish sold in the study areas is safe and hazardless. However, because of their non-degradable nature and tendency to accumulate in tissues and organs, we recommended that heavy metals contamination in imported frozen fish should be monitored regularly, and packages should contain concentration labels before releasing it into the market value chain.

Growth retardation and suppression of ubiquitin-dependent catabolic processes in the brackish water clam Corbicula japonica in response to salinity changes and bioaccumulation of toxic heavy metals

The brackish water clam (Corbicula japonica) is constantly exposed to stressful salinity gradients and high levels of heavy metals in the freshwater-saltwater interface of estuary environments, which are introduced from upstream regions and land. To identify the key molecular pathways involved in the response to salinity changes and heavy metal bioaccumulation, we obtained the transcriptomes of C. japonica inhabiting different salinities and heavy metal distributions in Gwangyang Bay (Korea) using RNA sequencing. Among a total of 404,486 assembled unigenes, 5534 differentially expressed genes were identified in C. japonica inhabiting different conditions, 1549 of which were significantly upregulated and 1355 were significantly downregulated. Correlation analyses revealed distinct gene expression patterns between the low and high conditions of salinity and heavy metal bioaccumulation. Functional annotation revealed significant downregulation of genes involved in “ubiquitin-dependent protein catabolic process,” “tricarboxylic acid cycle,” and “intracellular protein transport” in C. japonica from the high condition compared to the low condition. Transcription and translation pathways were significantly enriched in the high condition. Additionally, upon comparison of the low and high conditions by qRT-PCR and proteasome enzyme activity analyses, our findings demonstrated that environmental stress could suppress the ubiquitin-proteasome complex (UPC). Additionally, transcriptomic changes under high salinity stress conditions may be related to an increase in cellular protection by defense enzymes, which leads to more energy being required and a disruption of energy homeostasis. Ultimately, this could cause growth retardation in the clam C. japonica. In summary, this study provides the first evidence of UPC suppression induced by a combination of high salinity and heavy metal bioaccumulation stress in C. japonica, which could compromise the survival and growth of estuarine bivalves.

A comprehensive health risk assessment associated with bioaccumulation of heavy metals and nutrients in selected macrophytes of Loktak Lake, Manipur, India.

The Loktak Lake, a Ramsar site in Northeast India, is known for its rich biodiversity that includes a variety of macrophyte species, most of which have not been studied for their phytoremediation capacities and potential toxicity via consumption of the edible species. Therefore, a comprehensive assessment was conducted to evaluate the accumulation of selected heavy metals and nutrients in 10 dominant macrophyte species growing in Loktak Lake and to assess the potential health risks associated with consumption of the edible plants. The concentrations of nutrients such as total phosphorus (TP), total nitrogen (TN), potassium (K), calcium (Ca), magnesium (Mg), and heavy metals such as copper (Cu), manganese (Mn), zinc (Zn), and iron (Fe) were found to be in the order of plant > sediment > water. The bioaccumulation factors (BAFs) revealed high efficiency of most plants to accumulate heavy metals and nutrients in their tissues from the lake water and sediments, indicating their potential to be used as phytoremediators. Translocation factors (TFs) were also estimated to determine the efficiency of the plants to translocate elements from root to shoot. Colocasia esculenta and Polygonum perfoliatum exhibited the highest BAF values, whereas Colocasia esculenta, Hedychium flavum, Phragmites karka, and Oenanthe javanica exhibited the highest TF values for most elements. Target hazard quotients (THQs) revealed potential health risks associated with one or more heavy metals in the plants, except for Zn, whose THQ values were below the level of concern in all the edible plant species. The hazard index (HI) signifying potential non-carcinogenic health risk from the combined effects of all the heavy metals was highest for Polygonum perfoliatum, indicating a potentially higher risk to health if this edible macrophyte is regularly consumed in higher quantities and may pose long-term health effects to the exposed population.

Ecotoxicological risk assessment of metalloid contamination in the sediment and benthic fauna of a tropical lotic freshwater ecosystem in Southern Nigeria

The increasing exposure of freshwater bodies to pollutants and the bioaccumulation of heavy metals in body parts of aquatic organisms has raised concerns on the ecotoxicological and human health risk. This study evaluated the potential ecological and human health risk of heavy metal pollution in sediment and benthic fauna (Caridina africana) of the Osse River, Edo State, Nigeria. Using requisite equipment, samples of water sediment and C. africana were collected at designated stations from September 2015 to February 2017. Heavy metal concentrations in samples were determined using atomic absorption spectrophotometer. Result showed heavy metal contamination with concentration profiles of Fe > Zn > Mn > Cu > Ni > Pb > Cr > Cd > V in sediments and Fe > Zn > Mn > Cu > Ni > Cr > Pb > Cd > V in C. africana. The potential ecological risk index (PERI) values classified stations 1, 2 and 4 as of low ecological risk (PERI ≤ 150), while station 3 (PERI ≤ 300) was classified as of moderate ecological risk. Human health risk assessment for heavy metals in C. africana indicated significant non-carcinogenic health risk (HI > 1), and high carcinogenic risk to human health. The consumption of the contaminated C. africana, which is harvested in commercial quantities, portends health risk to the general public. There is need for urgent action in the abatement and regulation of identified anthropogenic activities responsible for the release of these heavy metals into the Osse River.

Human Health Risk Assessment for Exposure to Heavy Metals via Dietary Intake of Rainbow Trout in the Influence Area of a Smelting Facility Located in Peru.

Abandoned mining-metallurgical sites can significantly impact the environment and human health by accumulating heavy metals in aquatic ecosystems. The water in the sub-basin near an abandoned smelting facility in the city of La Oroya, Peru, is primarily used for pisciculture. The objective of this study was to assess the risk to human health from exposure to heavy metals via dietary intake of rainbow trout (Oncorhynchus mykiss) in the influence area of a smelting facility located in the central Andean region of Peru. The bioconcentration factor, biosediment accumulation factor, and consumption risks were evaluated using the Monte Carlo method. The results showed that the concentrations of elements (Zn > Pb > Cu > As) in rainbow trout muscle did not exceed the maximum limit (ML). However, the water significantly exceeded the ML for Pb in all sectors and As in the lower and middle parts of the river. The concentration of Pb in sediments also significantly exceeded the ML in the upper and lower parts of the river. Consequently, rainbow trout consumption in the study area presents risks to human health due to the bioaccumulation of heavy metals, with a 1.27% carcinogenic risk in samples from the lower part of the river.

Assessment of Heavy Metal Bioaccumulation in Freshwater Fish Species: Implications for Ecosystem Health and Human Well-being

This research article investigates the bioaccumulation of heavy metals in freshwater fish species from Tekrial Lake, Kamareddy, Thimmakpally Lake, Kamareddy, and Sriram Sagar Project, Nizamabad. The study focuses on Labeo rohita, Catla catla, and Channa punctata as model species to assess the effects of heavy metals, namely zinc(Zn), lead(Pb), ferrous(Fe), and manganese(Mg) on their vital organs including liver, gills, and muscles. Several experiments were conducted to evaluate the levels of heavy metal accumulation in fish tissues using advanced analytical techniques (Atomic Absorption Spectrometer(AAS),Inductively Coupled Plasma Mass Spectrometry). The results indicate a concerning presence of these heavy metals in the examined fish species, suggesting a potential threat to the aquatic ecosystem and human health through fish consumption. Furthermore, this study proposes effective methods to alleviate heavy metal contamination in freshwater fish. The recommended approaches include ion exchange, adsorption, reverse osmosis, and solvent extraction methods. These techniques show promising potential in removing heavy metals from fish tissues and restoring the ecological balance of freshwater ecosystems. Overall, this research sheds light on the alarming bioaccumulation of heavy metals in freshwater fish and emphasizes the detrimental effects on organ function. The proposed remediation strategies provide practical solutions for the mitigation of heavy metal pollution, ensuring sustainable aquatic environments and safeguarding human well-being.

Heavy metals in five commonly consumed fish species from River Swat, Pakistan, and their implications for human health using multiple risk assessment approaches

This study analyzed the levels of heavy metals bioaccumulation in commonly consumed riverine fish species, including G. cavia, T. macrolepis, G. gotyla, S. plagiostomus, and M. armatus from River Swat in Pakistan, and quantify their potential risk to children and adults in general and fisherfolk communities using multiple pollution and risk assessment approaches. The highest metal detected by inductive coupled plasma mass spectrometry (ICP-MS) was Zn, which ranged from 49.61 to 116.83 mg/kg, followed by Fe (19.25–101.33 mg/kg) > Mn (5.25–40.35 mg/kg) > Cr (3.05–14.59 mg/kg) > Ni (4.26–11.80 mg/kg) > Al (1.59–12.25 mg/kg) > Cu (1.24–8.59 mg/kg) > Pb (0.29–1.95 mg/kg) > Co (0.08–0.46 mg/kg) > Cd (0.01–0.29 mg/kg), demonstrating consistent fluctuation with the safe recommendations of global regulatory bodies. The average bioaccumulation factor (BAF) values in the examined fish species were high (BAF > 5000) for Pb, Zn, Mn, Cu, Cr, Ni, and Cd, bioaccumulate (1000 > BAF < 5000) for Co, and probable accumulative (BAF <1000) for Fe, and Al, while the overall ∑heavy metals pollution index (MPI) values were greater than one (MPI > 1) indicating sever heavy metals toxicity in G. cavia, followed by S. plagiostomus, M. armatus, G. gotyla, and T. macrolepis. The multivariate Pearson's correlation analysis identified the correlation coefficients between heavy metal pairs (NiCr, CuCr, PbCr, AlCo, CuNi, and PbNi), the hierarchical cluster analysis (CA) determined the origin by categorizing heavy metal accumulation into Cluster-A, Cluster-B, and Cluster-C, and the principal component analysis (PCA) discerned nearby weathering, mining, industrial, municipal, and agricultural activities as the potential sources of heavy metals bioaccumulation in riverine fish. As per human risk perspective, S.plagiostomus contributed significantly to the estimated daily intake (EDI) of heavy metals, followed by G.cavia > M.armatus > G.gotyla > T.macrolepis in dependent children and adults of the fisherfolk followed by the general population. The non-carcinogenic target hazard quotient (THQ) and hazard index (HI) values for heavy metal intake through fish exposure were < 1, while the carcinogenic risk (CR) for individual metal intake and the total carcinogenic risk (TCR) for cumulative Cr, Cd, and Pb intake were within the risk threshold of 10−6–10−4, suggesting an acceptable to high non-carcinogenic and carcinogenic risk for both children and adults in the fisherfolk, followed by the general population.

Cement dust inhalation induces hepato-renal dysfunction via tissue heavy metal bioaccumulation, histopathological and biochemical mechanisms

Cement dust inhalation induces hepato-renal dysfunction via tissue heavy metal bioaccumulation, histopathological and biochemical mechanisms