No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Toxic effect of heavy metals on aquatic environment
Abstract
The indiscriminate discharge of industrial effluents, raw sewage wastes and other waste pollute most of the environments and affect survival and physiological activities of target organisms. Metals in particular have a tendency to accumulate and undergo food chain magnification. Heavy metals affect all groups of organisms and ecosystem processes, including microbial activities. The bioaccumulation of trace elements in living organisms and biomagnification in them describes the processes and pathways of these pollutants from one trophic level to another, exhibiting the higher bioaccumulation ability in the organisms concerned. Some of these organisms, like fishes, are consumed by human beings. They could also cause catastrophic diseases like Minamata and Itai-Itai. Remediation approaches such as excavation and land fill, thermal treatment, electroreclamation and soil capping have been proposed depending on the extension, depth and kind of contamination, but all are expensive and environmentally destructive. Hence, reduction of toxic elements in aquatic environment can be progressively monitored by currently accepted and updated methods.
© 2010 International Formulae Group. All rights reserved.
Keywords: Heavy metals, effluents, Minamata, Itai-itai, Remediation, antacids.
... The consumption of fish and crustaceans had changed drastically. To combat the overexhaustion and harvesting of such resources from the wild, aquaculture-like establishment of fishponds were considered [5][6][7][8]. Rapid urbanization, improper land use planning and pattern, fast industrial development, and human population explosion are the major activities that affect the aquatic ecosystems [9,10]. Meanwhile, in terms of the feeds used in the fishponds, tannery and poultry wastes are often used as a cheap source of fish feed globally. ...
... communication program for all stakeholders including, but not limited to fishermen, fish pond owners, farmers, industries, if any, and the general public. 6. Conduct further research on other possible contamination of heavy metals in aquatic organisms aside from crab and bangus. ...
One of the common problem in fishponds is heavy metal contamination. Though there are some heavy metal elements that are naturally occurring, but due to human activities, their concentration goes beyond what is normal. In this study, health risks analysis using Estimated Daily Intake (EDI), Total Hazard Quotient (THQ), Target Cancer Risk (TCR) were done to assess if the quantities of the heavy metals, such as: Arsenic, Cadmium, Chromium, Lead, and Mercury, impose risks to consumer. Arsenic had the highest concentration among all other heavy metals in crab aligue, having 46.83 mg/kg. The consumption of bangus meat may result in an EDI that is greater than PTDI, especially for Arsenic [15.22731-18.10317 μg kg−1 BW d−1]. Similarly, consuming crab aligue may also result to a high EDI for Arsenic [2.48197-5.27841μg kg−1 BW d−1]. THQ was also evaluated as well as the sum of individual heavy metal values which is the Hazard Index (HI) that exceeded to 1 multiple times. In terms of TCR levels, all of the heavy metals exceeded the acceptable limit for cancer risks. Shapiro-Wilk Test had shown non-normal distribution of data for EDI, THQ, and TCR. Spearman’s Correlation Test, meanwhile, suggested that there is a significant relationship between the quantities of heavy metals in bangus meat and crab aligue as well as EDI, THQ, and TCR. In general, based on the health risks assessments (EDI, THQ, and TCR), Arsenic, an established carcinogen, can be the greatest contributor in developing risks and disease, while the varying concentration of Chromium and Cadmium in the samples may also pose risks to consumers. This implies that strict management measures should be implemented to mitigate or lessen the discharge of these heavy metals in the aquatic systems.
... The heavy metal contaminants in aquatic ecosystems being in soluble or suspension form tend to settle down at the bottom and be ingested by plants and animals or absorbed by sediments (Baby et al., 2010;Opaluwa et al., 2012). In the * Corresponding author: victorpanga996@gmail.com aquatic ecosystem, 99% of the heavy metal contaminants are stored in the sediments (Shen et al., 2019). ...
... Heavy metals in the sediments cause detrimental impacts that can change the aquatic ecosystem and can reach the food chain through plants and aquatic animals (Mataba et al., 2016). Among the inhabitants of the aquatic ecosystem that are largely affected by the detrimental impacts of the heavy metal pollutants are fish (Baby et al., 2010). Generally, fish can be used to assess the environmental health of the aquatic ecosystem and bioaccumulation of heavy metals is known to depend on the nature of the aquatic environment, type of heavy metal, rate of absorption, deposition and excretion (Miri et al., 2017;Mielcarek et al., 2022). ...
Concentrations of heavy metals namely Cr, Fe, Cu, Zn, As, Cd and Pb in African Sharptooth Catfish (clarias gariepinus) and sediment from river Mtakuja Tanzania were analyzed using the Energy Dispersive X-ray Fluorescence spectrometry technique. 32 samples from fish and sediment were investigated. The results show that the concentration of heavy metals was higher in upstream areas than in the downstream area. The concentration of Fe of 428.5 mg/kg in catfish from the upstream area was about 2 times 243.8 mg/kg obtained from the same fish in the downstream area. Similar cases observed for sediments with Fe concentration of 127626.9 mg/kg from upstream that was about 6 times higher than that of 21460.3 mg/kg from downstream area. The concentration of 44.8 mg/kg for Cu in the upstream area sediment was also about 2 times higher than 23.2 mg/kg in the downstream area sediment, while for as the concentration of 13.2 mg/kg was measured in the upstream, which is which is more than 5 times 2.5 mg/kg measured in downstream. The concentration of Cr in the catfish was 17.6 mg/kg which is higher than the permissible limit values of 0.8 mg/kg set by the European Commission (EC), 0.2 mg/kg set by the Food and Agricultural Organization (FAO) and 0.15 mg/kg the World Health Organization (WHO) limit. Moreover, the concentration of Cd was 3.0 mg/kg, which is above the permissible level of 0.2 mg/kg recommended by the EC and WHO. A positive correlation exists between the Cu, Pb, Fe and Cd concentration found in sediments and fish samples. The results show that the river Mtakuja is polluted by mining waste, domestic and agrochemical activities. This suggest that, there is a need for regular monitoring of heavy metal in river Mtakuja in order to monitor and protect aquatic organisms and health of benefactors of this river.
... In this sense, marine ecosystems are one of the systems most affected by pollution because humans have used them as a dumping ground for their waste, disregarding their complexity and dynamics. Among the pollutants, the accumulation of HMs in marine ecosystems is of vital importance because they can have devastating effects on the ecological balance of the environment and biodiversity [5,6]. It would be beneficial to clarify that, among the metals, some are essential elements that play biological roles but can be toxic at high concentrations, while others are non-essential and do not have known biological functions. ...
... It would be beneficial to clarify that, among the metals, some are essential elements that play biological roles but can be toxic at high concentrations, while others are non-essential and do not have known biological functions. It is well-known that chronic HM exposure can have serious long-term health effects [5,7,8]. ...
The escalating global anthropogenic activities associated with industrial development have led to the increased introduction of heavy metals (HMs) into marine environments through effluents. This study aimed to assess the toxicity of three HMs (Cr, Cu, and Cd) on organisms spanning different trophic levels: Phaeodactylum tricornutum (a primary producer), Artemia salina (a primary consumer), and Aurelia aurita (a secondary consumer). The EC50 values obtained revealed varying relative toxicities for the tested organisms. Phaeodactylum tricornutum exhibited the highest sensitivity to Cu, followed by Cd and Cr, while Artemia salina displayed the highest sensitivity to Cr, followed by Cu and Cd. A. aurita, on the other hand, demonstrated the highest sensitivity to Cu, followed by Cr and Cd. This experimental investigation further supported previous studies that have suggested A. aurita as a suitable model organism for ecotoxicity testing. Our experiments encompassed sublethal endpoints, such as pulsation frequency, acute effects, and mortality, highlighting different levels of sensitivity among the organisms.
... Aquatic biota has been used to observe heavy metal contamination in aquatic environments for many years (Kamaruzzaman et al., 2011) and among the aquatic organisms, fishes occupy an important position in the field of aquatic toxicology (Akan et al., 2012). Resident fish have been shown in studies as good indicators of aquatic ecosystem health and environmental change, especially in the case of toxic water pollution (Baby et al., 2010;Ibemenuga, 2013). Metals tend to accumulate in fish through bio-magnification effects in the food chain and they can enter into human body and accumulate in the human tissues to pose prolonged harmfulness, which may disturb growth, development, reduce hemoglobin, create cancer, damage the body tissues and the nervous system, and in extreme case, may also cause fatality of living organisms (Latifah and Met, 2014). ...
... However, due to the harmful effects of cadmium and lead on both fish and humans, as well as the fact that any carcinogenic substance, such as Pb and Cd, carries a risk of cancer development at any dose other than zero, the discovery of cadmium and lead in fish muscle is concerning. Long-term exposure to cadmium has been linked to renal failure and obstructive lung disease, and it has also been documented to produce itaitai disease in fish eaters (Cheung et al., 2008;Baby et al., 2010). Pb has been linked to long-term neurological damage in children (hyperactivity, inability to focus, low IQ), decreased male fertility, and suppression and alteration of the manufacture of hemoglobin, which results in inadequate oxygen delivery and anemia in man (Landis and Yu, 2003;Bradl, 2005). ...
Agricultural and domestic activities around dams in Nigeria involve the use of agrochemicals and insecticides to boost production and combat insect pests respectively. The study aimed to ascertain metals contents and assess the hazards associated with heavy metals in Oreochromis niloticus in three major dams in Ekiti State. Fish samples were collected for 24 months. Metal concentrations in fish samples were determined using spectrometry. The metals concentrations in the tissues were at lower concentrations compared to the maximum acceptable limits in food by Food and Agricultural Organization (FAO) and World Health Organization (WHO). Metals accumulation pattern revealed that the accumulation of the essential metals were higher than those of the non-essential metals in the fish tissues. There were significant seasonal variations in the concentrations of metal in fish tissues within the dam and among the dams. Significant relationships existed at P < 0.05 or P < 0.01 between some of the metals and the fish body weight and body length in the different dams while in others the relationships were not significant. Human health risk assessment showed no significant non-carcinogenic adverse health risk. Carcinogenic health assessment indicates that the utilization of the species as a protein source does not currently pose public health risk to consumers. However, the discovery of cadmium and lead in fish muscle is of great concern because of their toxic effects on human. Therefore, there is a need for close monitoring of these toxic metals contamination to prevent their excessive accumulation in the human food chain.
... In addition to pesticides, there are a variety of pollutants present in aquatic ecosystems, such as potentially toxic metals. Originating from mining residues, leaching from landfills, urban runoff, and industrial waste (Gautam et al. 2014), these metals cannot be biodegraded, and bioaccumulation makes them highly hazardous (Baby et al. 2011). ...
The excessive use of pesticides in agriculture and the widespread use of metals in industrial activities and or technological applications has significantly increased the concentrations of these pollutants in both aquatic and terrestrial ecosystems worldwide, making aquatic biota increasingly vulnerable and putting many species at risk of extinction. Most aquatic habitats receive pollutants from various anthropogenic actions, leading to interactions between compounds that make them even more toxic. The aim of this study was to assess the effects of the compounds Chlorpyrifos (insecticide) and Cadmium (metal), both individually and in mixtures, on the cladocerans Ceriodaphnia rigaudi and Ceriodaphnia silvestrii. Acute toxicity tests were conducted for the compounds individually and in mixture, and an ecological risk assessment (ERA) was performed for both compounds. Acute toxicity tests with Cadmium resulted in EC50-48 h of 0.020 mg L⁻¹ for C. rigaudi and 0.026 mg L⁻¹ for C. silvestrii, while tests with Chlorpyrifos resulted in EC50-48 h of 0.047 μg L⁻¹ and 0.062 μg L⁻¹, respectively. The mixture test for C. rigaudi showed the occurrence of additive effects, while for C. silvestrii, antagonistic effects occurred depending on the dose level. The species sensitivity distribution curve for crustaceans, rotifers, amphibians, and fishes resulted in an HC5 of 3.13 and an HC50 of 124.7 mg L⁻¹ for Cadmium; an HC5 of 9.96 and an HC50 of 5.71 μg L⁻¹ for Chlorpyrifos. Regarding the ERA values, Cadmium represented a high risk, while Chlorpyrifos represented an insignificant to a high risk.
... Among these compounds are the heavy metals from anthropogenic sources, mainly due to intense mining activity and environmental disasters, which release large amounts of chemical compounds in the aquatic environment [5,8]. Heavy metals can have a high bioaccumulation and bio magnification capacity along the food chain and accumulate in water and sediments [5,9]. In addition, they are an important protein resource and are part of human food composition, so fish represent one main sources of heavy metal intake for humans via food chain [10]. 2 The mechanisms the action of the heavy metals in organisms of the aquatic ecosystem is very broad and it is not yet clear. ...
Environmental pollution is one of today's main ecological and social concerns. Among these pollutants are the heavy metals present in the burning of fossil fuels, mining, smelting of metallic minerals, fertilizers and pesticides. Billions of tons of heavy metals are emitted every year from industrial chimneys and sewers, contaminating the hydrosphere and polluting rivers, lakes and seas. In this context, freshwater fish are the most affected due to their proximity to the source of contamination and are therefore used as bioindicators in assessing environmental impact following exposure to metals. However, our understanding of the effects of heavy metals on detoxification organs - such as the liver and gills - in freshwater fish in situ is still limited. Therefore, we conducted a systematic review to determine the main changes and mechanisms involved in morphological modifications in the liver and gills of cichlid fish following exposure to heavy metals in situ. Based on a structured search, 36 original articles were selected from the PubMed and SCOPUS databases. The selection of studies and the identification of duplicates were identified by Rayyan, and the study selection process was presented in the PRISMA statement diagram. Bias analysis was carried out using the Software Review Mananger (RevMan) 5.3, from the Cochrane Collaboration. Thirty-six studies were selected which showed negative effects attributed to environmental contamination by heavy metals, ranging from bioaccumulation to morphophysiological alterations. Almost all the heavy metals analyzed were found in the liver and gill tissues, especially cadmium, copper, lead, zinc, iron and manganese. In view of the continuous morphophysiological changes identified in the liver and gill studies, it is possible to state that bioaccumulation analyses, combined with these configurations, are emerging as crucial tools for assessing and guiding environmental monitoring. This approach aims not only to preserve but also to strengthen the integrity of the aquatic ecosystem and the ichthyofauna.
... Metal heavy cadmium can't destroy by organisms live in the environment and will accumulated to environment. Metal the weight inside waters though level relatively low, yes absorbed and accumulated in a way biological by aquatic animals and will involve in system chain food (Baby et al., 2010;Eko, 2020;Singh et al., 2022;Zhang & Reynolds, 2019). ...
Rawa Lake Taliwang is the lifeblood of the West Sumbawa Regency community. The lake is surrounded by extensive agricultural areas, making the activities of local farmers a significant contributor to the accumulation of heavy metals in the region. This study aims to determine the cadmium (Cd) content in snakehead fish (Channa striata ) and assess its suitability for consumption. Sampling was conducted using purposive sampling with direct observation at Lake Rawa Taliwang . Nets or traps were employed at two stations, with two replications at each station. Data analysis involved calculating the cadmium content in the laboratory using Atomic Absorption Spectroscopy (AAS). The results revealed that the cadmium concentration in snakehead fish from Lake Rawa Taliwang was 0.45 mg/kg (ppm). This concentration exceeds the permissible limit for metal contamination in food, as stated in BPOM Regulation Number 9 of 2022. As a result, the snakehead fish is deemed unfit for consumption.
... The average mean value of Lead (Pb) in the water sample of this study across all the stations falls above the WHO recommended level of 0.01 mg/L in all the stations. However, the value is lower than the highest level of 0.55 mg/L observed in the surface water sample investigated in Ekiti State, Nigeria, as reported by Joseph et al. 29 . The mean chromium levels found in the samples stations were higher than WHO permitted chromium level of 0.05 mg/L observed in the sample stations. ...
Background and Objective: Freshwater is one of the major natural resources used for myriad of purposes. This research was conducted to assess the presence of some pollutants in Hadejia River Jigawa State and their potential toxic effects on Oreochromis niloticus (Nile tilapia). Materials and Methods: Water and fish samples were collected fortnightly for four months, between March and June 2022, from four designated stations. The samples were analysed for heavy metal contamination, physicochemical parameters and the haematological indices of fish blood. Results: The physicochemical parameters such as temperature, pH, conductivity, dissolved oxygen, turbidity, total dissolved solids and total suspended solids were within acceptable limits, except for turbidity which exceeded the recommended level. The haematological indices indicated lower than normal packed cell volume (PCV) and varying levels of haemoglobin (Hb). The concentrations of lead (Pb), chromium (Cr), cadmium (Cd) and nickel (Ni) exceeded the permissible limits set by WHO/USEPA, while zinc and copper levels were below the permissible limits. Conclusion: These findings highlight the contamination present in the surface water and emphasize the urgency for implementing measures to control these pollutants.
... Aquatic organisms may absorb these heavy metals (Poopak et al., 2023). Subsequently, the metals accumulate in the food chain, affecting organisms from primary producers to final consumers (Baby et al., 2010;Sharma & Agrawal, 2005). However, certain heavy metals are essential in appropriate dietary quantities to facilitate essential bodily functions in the organism (Raeeszadeh et al., 2022). ...
Aquaculture, as a strategic and developmental industry, plays an important role in ensuring food security and economic stability within countries. This crucial sector faces various influences, including infectious and nutritional diseases. Certain minerals function as essential nutrients, playing a main role in processes across all aquatic animals when present in appropriate dietary proportions. Studies showed that some heavy metals serve as a catalyst for various biological functions, including the maintenance of colloidal systems, acid-base balance, bone formation, and the regulation of fundamental natural elements such as vitamins, hormones, and minerals. Fish acquire essential elements crucial for their well-being through both diet and water sources. Adequate levels of essential elements, such as iron, zinc, copper, cobalt, manganese, and selenium, in the diet contribute to enhanced growth, increased survival rates, improved disease resistance, and heightened specific immunity in fish. When incorporated in appropriate quantities, these elements play a pivotal role in disease prevention, fostering the production of high-quality fish, minimizing economic losses, and solidifying aquaculture as a robust and profitable industry. This article aims to delve into the immunological effects induced by metal elements, specifically copper (Cu), cobalt (Co), manganese (Mn), zinc (Zn), and selenium (Se), in diverse fish species. The objective is to underscore the significance of this exploration, paving the way for the development of more potent immune supplements in the future. These supplements have the potential to improve growth, fortify immune responses, and enhance resilience against diseases in various fish species.
... Metals, such as those present in iron ore tailings, are among the contaminants that can alter the dynamics of aquatic environments (Fleeger et al., 2003;Baby et al., 2010). The high toxicity of metals is due to their stability in organisms as they are not degradable (Rocha and Azevedo, 2015). ...
Here, we used distribution models to predict the size of the environmentally suitable area for shrimps of fishing interest that were impacted by the tailing plume from the collapse of the Fundão Dam, one of the largest ecological disasters ever to occur in Brazil. Species distribution models (SDMs) were generated for nine species of penaeid shrimp that occurred in the impacted region. Average temperature showed the highest percentage of contribution for SDMs. The environmental suitability of penaeids varied significantly in relation to the distance to the coast and mouth river. The area of environmental suitability of shrimps impacted by tailings plumes ranged from 27 to 47 %. Notably, three protected areas displayed suitable conditions, before the disaster, for until eight species. The results obtained by the SDMs approach provide crucial information for conservation and restoration efforts of coastal biodiversity in an impacted region with limited prior knowledge about biodiversity distribution.
... Heavy metals, including cadmium (Cd), have become a severe issue and attract expert attention because of their toxicity, accumulation, and biomagnification in living organisms, accumulating in aquatic species and entering the food chain [1]. The primary sources of metal pollution are industrial production and waste, fossil fuel combustion, mining, electroplating, dye and pigment manufacturing, and agricultural fertilizers [2]. ...
Cadmium (Cd) has become a severe issue in relatively low concentration and attracts expert attention due to its toxicity, accumulation, and biomagnification in living organisms. Cd does not have a biological role and causes serious health issues. Therefore, Cd pollutants should be reduced and removed from the environment. Microalgae have great potential for Cd absorption for waste treatment since they are more environmentally friendly than existing treatment methods and have strong metal sorption selectivity. This study evaluated the tolerance and ability of the microalga Tetratostichococcus sp. P1 to remove Cd ions under acidic conditions and reveal mechanisms based on transcriptomics analysis. The results showed that Tetratostichococcus sp. P1 had a high Cd tolerance that survived under the presence of Cd up to 100 µM, and IC50, the half-maximal inhibitory concentration value, was 57.0 μM, calculated from the change in growth rate based on the chlorophyll content. Long-term Cd exposure affected the algal morphology and photosynthetic pigments of the alga. Tetratostichococcus sp. P1 removed Cd with a maximum uptake of 1.55 mg g⁻¹ dry weight. Transcriptomic analysis revealed the upregulation of the expression of genes related to metal binding, such as metallothionein. Group A, Group B transporters and glutathione, were also found upregulated. While the downregulation of the genes were related to photosynthesis, mitochondria electron transport, ABC-2 transporter, polysaccharide metabolic process, and cell division. This research is the first study on heavy metal bioremediation using Tetratostichococcus sp. P1 and provides a new potential microalga strain for heavy metal removal in wastewater.
Abbreviations:BP: Biological process; bZIP: Basic Leucine Zipper; CC: Cellular component; ccc1: Ca (II)-sensitive cross complementary 1; Cd: Cadmium; CDF: Cation diffusion facilitator; Chl: Chlorophyll; CTR: Cu TRansporter families; DAGs: Directed acyclic graphs; DEGs: Differentially expressed genes; DVR: Divinyl chlorophyllide, an 8-vinyl-reductase; FPN: FerroportinN; FTIR: Fourier transform infrared; FTR: Fe TRansporter; GO: Gene Ontology; IC50: Growth half maximal inhibitory concentration; ICP: Inductively coupled plasma; MF: molecular function; NRAMPs: Natural resistance-associated aacrophage proteins; OD: Optical density; RPKM: Reads Per Kilobase of Exon Per Million Reads Mapped; VIT1: Vacuolar iron transporter 1 families; ZIPs: Zrt-, Irt-like proteins.
... 2 heavy metals to effluents through their various manufacturing procedures, such as tanning, dyeing, mining, battery and electronic manufacturing, and electroplating [3,4]. Electroplating is a major industrial activity that has environmental impacts and produces 29 % of hazardous and toxic wastewater [5]. ...
A R T I C L E I N F O Keywords: MOF sensor Co 2+ and Pd 2+ removal Wastewater Fluorometric method A B S T R A C T The study aimed to develop an innovative Aluminum-based sensitive sensor material, HPDTP-Al MOF sensor. The sensor was meticulously crafted through the diazotization of the NH 2-MIL53(Al) MOF and coupling it with resorcinol to develop the HPDTP-Al MOF sensor material. The performance, selectivity, and sensitivity of the developed HPDTP-Al MOF were thoroughly evaluated. It successfully detected ultra-trace concentrations of Co 2+ and Pd 2+ ions using spectrophotometric and fluorometric methods. The MOF was tested by detecting and removing Co 2+ in real electroplating wastewater samples. It was also used to recover Pd 2+ ions from electronic wastes. To comprehensively characterize the HPDTP-Al MOF sensor material, a range of techniques involving TEM, XRD, BET, SEM, and XPS were employed. These methods not only confirmed the successful synthesis of the sensor material, but also provided valuable insights into its surface and structural properties. The optimization process involved fine-tuning the conditions for Co 2+ and Pd 2+ ions detection using both colorimetric and fluo-rometric approaches. Impressively, the sensor material exhibited swift detection capabilities, achieving a stable spectroscopic signal in under 1 min. Furthermore, the study delved into the sensor material's recyclability, which exhibited promising results, enabling its efficient reuse for up to 6 cycles. The exploitation of 0.1 M HCl and 0.1 Citrate as an eluent for the regeneration of the sensor material. The sensor's real-world potential was assessed through the analysis of diverse sample types, including electroplating wastewater for the removal and detection of Co 2+ ions and the recovery of valuable Pd 2+ ions from electronic wastes. These findings unequivocally emphasize the sensor material's promise for practical applications in various real-world scenarios, especially as environmental solutions.
... solid waste disposal, industrial or domestic effluents). Heavy metals cannot be easily degraded or decomposed and they have ability of bioaccumulation once get into the ecosystem via drinkable water impairing the quality of water and subsequently human health (Baby et al., 2010;Meng et al., 2021). There are some biologically essential heavy metals which human body requires in trace amounts such as iron, cobalt, copper, zinc, molybdenum, and manganese. ...
The concentration of lead (Pb), cadmium (Cd), aluminium (Al), manganese (Mn), and iron (Fe) in spring waters in the vicinity of Kochani was investigated to ascertain the health risk exposure. Heavy metal water contamination is possible mostly due to wrongful human activities either industrially or residentially and exposure to toxic doses of heavy metals can cause acute and chronic diseases. To examine heavy metal contamination of spring waters as well as possible seasonal variations, water samples in two seasons, autumn 2021 and spring 2022 were collected. For this aim, ten locations within the area of Kochani were selected. The spring water samples were collected directly from the source or from the catchment that was made. The samples were collected in appropriate bottles, previously washed with detergent and rinsed with distilled water. The examination of heavy metals was carried out immediately after sampling using UV spectrophotometric method, with an absorption spectrum of 190-1100 nm. The results have revealed no major deviations from the maximum concentrations allowed for Pb, Cd, Al, Mn, and Fe defined within the Official Guidelines in the Republic of North Macedonia, except moderately increased levels of lead in two samples during autumn season and manganese in four samples in the spring season 2022. Key words: heavy metal levels, spring water, UV spectrophotometry, human health
... Additionally, the accumulation of heavy metals in filter-feeding organisms such as bivalve mollusks poses health risks to humans, as these creatures may be consumed by humans, introducing these contaminants into the human food web and raising significant public health concerns. In conclusion, pollution stemming from heavy metals and trace elements in marine environments has far-reaching and severe repercussions for biodiversity, the health of ecosystems, and human well-being, emphasizing the urgent need to address this issue with effective mitigation measures and environmentally sustainable management (Baby et al., 2010;Bánfalvi, 2011;Bradney et al., 2019;Murphy, 1981). The decontamination of heavy metals in marine ecosystems represents a complex and pivotal challenge from both an environmental and public health perspective. ...
... The complex organic compounds present in the wastewater, as reflected in the BOD values, emphasized the substantial organic load, which could exert oxygen demand and adversely affect aquatic ecosystems (Ngobeni et al., 2021). The detection of heavy metals such as zinc, nickel, and cadmium raised concerns about the wastewater's potential long-term environmental impact (Baby et al., 2011). These metals, even in trace amounts, could have detrimental effects on aquatic life and pose risks to ecosystem health. ...
The treatment of slaughterhouse wastewater is a complex task demanding careful consideration due to its challenging nature. Therefore, exploring more sustainable treatment methods for this particular type of wastewater is of utmost significance. This research focused on the impact of electrode materials, specifically graphite and titanium, on the efficiency of microbial fuel cells (MFCs) and electro‐Fenton systems in treating slaughterhouse wastewater. Both graphite and titanium electrodes displayed increasing current density trends, with titanium outperforming graphite. Titanium showed superior electron transfer and current generation (2.2 to 21.2 mA/m ² ), while graphite ranged from 2.4 to 18.9 mA/m ² . Titanium consistently exhibited higher power density, indicating better efficiency in converting current to power (0.059 to 22.68 mW/m ² ), compared to graphite (0.059 to 12.25 mW/m ² ) over the 48‐h period. In removal efficiency within the MFC system alone, titanium exhibited superior performance over graphite in key parameters, including zinc (45.5% vs. 37.19%), total hardness (39.32% vs. 29.4%), and nitrates (66.87% vs. 55.8%). For the electro‐Fenton system with a graphite electrode, the removal efficiency ranged from 34.1% to 87.5%, with an average efficiency of approximately 56.2%. This variability underscores fluctuations in the efficacy of the graphite electrode across diverse wastewater treatment scenarios. On the other hand, the electro‐Fenton system employing a titanium electrode showed removal efficiency values ranging from 26.53% to 89.99%, with an average efficiency of about 68.4%. The titanium electrode exhibits both a comparatively higher and more consistent removal efficiency across the evaluated scenarios. On the other hand, the integrated system achieved more than 90% removal efficiency from most of the parameters. The study underscores the intricate nature of slaughterhouse wastewater treatment, emphasizing the need for sustainable approaches.
Practitioner Points
Microbial fuel cell (MFC) and electro‐Fenton were investigated for slaughterhouse wastewater treatment.
The MFC microbial activity started to decrease after 24 h.
The integrated system achieved up to 99.8% removal efficiency (RE) for total coliform bacteria.
Up to 99.4% of RE was also achieved for total suspended solids (TSS).
The integrated system highly improved RE of the pollutants.
... Despite being responsible for "less visible pollution", they have the dangerous ability to bioaccumulate along the food chain and cause negative effects and alterations of ecosystem balance such as reduction of the growth of organisms and increase in mortality and anomalies in development (Khayatzadeh and Abbasi, 2010). It is also important to consider that they can have effects on organisms exposed to single metals or mixture of metals with consequent synergistic effects (Baby et al., 2011). ...
Sponge farming has been experimentally performed for more than 100 years, with early attempts mainly devoted for the supply of bath sponges and for ornamental purposes. During the last decades, sponge farming has been proposed to produce biomass specifically for those species from which many structurally diverse bioactive compounds were isolated, frequently present in a low concentration that limits their commercial production. This point is very important because it offers an environmental-friendly approach for the use of sponges as a source of natural compounds for pharmacological, cosmeceutical, and nutraceutical industries. In addition, sponges can have an ecological role as filter-feeding animals with a great significance in marine benthic communities. Thanks to their aquiferous system, they can filter large amounts of sea water, retaining up to 80% of suspended particles, resulting in a good system to bioremediate the marine environment from different contaminants. Remarkably, few attempts at integrating aquaculture systems were performed by combining the increase in sponge biomass and their use for bioremediation, showing impressive results and opening new possibilities in the aquaculture sector. This review concerns both in situ and lab-based aquaculture methods for the production of sponge biomass and for the sponge-related bioremediation of the marine environment focusing on microorganisms and contaminants (heavy metals, pesticides, microplastics, and others). Moreover, a first overview about integrated aquaculture combining biomass increase and bioremediation, as a challenging perspective for marine biotechnologies, is included.
... They are produced naturally, however could be released into the environment through industrial activities including metal smelting, burning of fuels, alloy processing, and mining (Lo et al., 2012). THMs can contaminate water, soil, and vegetation through surface runoff as well as agricultural and industrial effluents (Baby et al., 2010;Smitha et al., 2007). Their non-degradable nature promotes bio accumulation and environmental persistence, and they are easily deposited in human tissues through diet and water (Sonone et al., 2021). ...
Background: Toxic Heavy Metals (THMs) threaten food safety and result in human poisonings. It seems to be few studies on THMs contamination in food chain in developing countries. Current investigation determine the concentration and health risk of arsenic (As), cadmium (Cd), lead (Pb), as well as mercury (Hg) in fish and water at Nsukka, Metropolis, Enugu state, Nigeria. Methods: Forty eight samples; 24 (catfish and tilapia) fish and 24 (borehole, sachet, and bottled) water were randomly collected from two major markets and districts in Nsukka Metropolis and were evaluated for THMs using Atomic Absorption Spectrophotometer. The Estimated Daily Intake, Target Hazard Quotient, Hazard Index, and Cancer Risk (CR) were assessed as well. Results: THMs analaysis showed that As, Cd, and Hg were at 100% and Pb being at 16% in all the fish samples while 12.5% of fish of exceeded the Hg Maximum Permissible Limit (MPL) of 0.050 mg/kg, that not statistically significant (p>0.05).On the other hand, based on the analysis of all water samples, Hg and As were detected at 100% rate, Cd at 58.3% while Pb was not identified. The values above the MPL appeared to be 9 (37.5%), 2 (8.3%), and 3(12.5%) for Hg, As, and Cd, respectively in water while not statistically significant (p>0.05). The mean value of Hg (0.06425 mg/kg) in roasted fish as well as Cd (0.0065 and 0.0105) mg/ml in tap and bottled water respectively surpassed the MPL although not statistically significant (p>0.05). The Estimated Daily Intake of THMs except Cd in fish were proved to be within the Provisional Tolerable Daily Intake in contrast with As and Cd in water. CR is present both in children and adults with CR value >1. Conclusion: The finding of THMs in fish and water above the MPL is regarded as potential health risk for the consumers of such contaminated water and fish in the investigation scope.
... Accordingly, with heavy metals exposure, Nile tilapia was susceptible to Streptococcus agalactiae infection, and their survivability declined [84]. Similarly, in aquatic systems, heavy metals rapidly accumulate in fish tissues, hindering their normal physiological functions and leading to high mortalities [87,88]. In addition, Abdel-Tawwab et al. [84] found that Nile tilapia could withstand exposure to waterborn Zn regimes, showing high survival rates of 96.7% and 100.0%. ...
Background
Pollution with heavy metals (HMs) is time- and concentration-dependent. Lead and zinc pollute the aquatic environment, causing severe health issues in aquatic animals.
Materials and methods
Nile tilapia, the predominant cultured fish in Egypt, were experimentally exposed to 10% of LC50 of lead nitrate (PbNO3) and zinc sulfate (ZnSO4). Samples were collected in three different periods, 4, 6, and 8 weeks, in addition to a trial to treat the experimental fish infected with Aeromonas hydrophila, with an antibiotic (florfenicol).
Results
Liver enzymes were linearly upsurged in a time-dependent manner in response to HMs exposure. ALT was 92.1 IU/l and AST was 82.53 IU/l after eight weeks. In the eighth week of the HMs exposure, in the hepatic tissue, the levels of glutathione peroxidase (GPx), catalase (CAT), and metallothionein (MT) were increased to 117.8 U/mg prot, 72.2 U/mg prot, and 154.5 U/mg prot, respectively. On exposure to HMs, gene expressions of some cytokines were linearly downregulated in a time-dependent manner compared to the control. After four weeks of exposure to the HMs, the oxidative burst activity (OBA) of immune cells was decreased compared to the control 9.33 and 10.3 cells, respectively. Meanwhile, the serum bactericidal activity (SBA) significantly declined to 18.5% compared to the control 32.6% after eight weeks of exposure. Clinical signs of A. hydrophila infection were exaggerated in polluted fish, with a mortality rate (MR) of 100%. The re-isolation rate of A. hydrophila was decreased in fish treated with florfenicol regardless of the pollution impacts after eight weeks of HMs exposure.
Conclusion
It could be concluded that the immune suppression and oxidative stress resulting from exposure to HMs are time-dependent. Clinical signs and post-mortem lesions in polluted fish infected with A. hydrophila were prominent. Infected-Nile tilapia had weak responses to florfenicol treatment due to HMs exposure.
... Metals constitute a core group of aquatic contaminants causing cellular toxicity, mutagenicity, and carcinogenicity in animals due to their high toxicity, long persistence, and non-biodegradable nature in the food chain [17][18][19]. Fish are exposed to heavy metals in different ways, such as via the direct intake of water, ion-exchange of dissolved heavy metals through phospholipid membrane of gills, and adsorption on the surface of tissues and membrane [20,21]. Among different fish tissues, heavy metal distribution also depends upon the kind of exposure (dietary or aqueous) [22]. ...
The current study was conducted to assess the concentration of heavy metals in rohu (Labeo rohita) and common carp (Cyprinus carpio). A total of three sites namely Rawal Lake Islamabad, Head Balloki, and a private fish farm in Muridke were selected. Fish were dissected and tissues from the liver, kidneys, gills, and muscles were separated. Chemical digestion of samples was carried out with aqua regia. Three metals namely chromium (Cr), cadmium (Cd), and mercury (Hg) were detected by using atomic absorption spectroscopy in the labs of Pakistan Council of Scientific and Industrial Research (PSCIR), Lahore, Pakistan. All metals were found at a higher level in different tissues of both the fish species. The overall trend of metals in the two fish species namely rohu and carp was recorded as Hg > Cd > Cr. It was observed that the level of Hg remained very high as compared to other metals. Statistical analysis was performed using one-way ANOVA and significant differences at p < 0.001 were noticed for the metals in different organs. While, independent sample t test showed non-significant differences at p > 0.483 between the two fish species. The liver was found to have the highest metal load, followed by the kidneys and gills. The metal load was above the permissible limit set by World Health Organization (WHO). However, the heavy metals concentration in muscles was below the permissible limit. It was noticed that heavy metal contamination was higher in Rawal Lake as compared to the private fish farm. It was concluded that contaminated water bodies are affecting the exposed organisms. So, there is a need to save them from pollutants for the best survival of aquatic life.
... Contamination by trace elements affects the marine organism at a cellular level and can damage the ecological balance. There are generally three ways for trace elements to enter any aquatic species, which are either by ingesting food, or through body surface, or through gills while breathing (Baby et al. 2010). These trace elements become toxic only when these gets accumulated in the soft tissues and not metabolized by the body. ...
Trace elements constitute a substantial factor in the course of life processes. Trace elements
can be found consistently in the environment. Trace elements, despite being present in exceedingly low
concentrations, are vital for life in the oceans. A multitude of definitions for the term "trace elements" have
been attributed by various scientists. However, it was termed because of their levels of concentrations
contributed to our lives and environment; a small increase or reduction in their levels of concentration may
prove toxic to the flora and fauna of the Earth, which could be due to extensive productivity and human
intervention. The main aim of the review is therefore to highlight the main concern of the effects these
trace elements carry on marine life, producing a disturbance in the biota that not only affects productivity,
and their nutrient cycle but also contributes to the marine environment. Hence, the overarching objective
of this review is to underscore the fact that trace elements continue to be contaminants of significance that
necessitate scientific scrutiny. Therefore, finding a better alternative to monitor the contamination is an
absolute necessity, considering their toxicity levels.
... Untreated wastewater from municipal, domestic sewage, and industry directly discharged into the natural water system leads to water contamination, industrial effluents, water tank leakages, dumping beside water bodies, and atmospheric deposition, which are some major sources through which these heavy metals entry into aquatic ecosystem. Electroplating is a major contributor to pollution because it releases heavy metals via water, air emissions, and solid waste in an environment that has been reported to contain high levels of heavy metals such as nickel, iron, lead, zinc, chromium, cadmium, and copper (Baby et al. 2010). Mining and ore processing are important sources of heavy metal contamination in the soil, and the recovery of ecosystems from mining operations might take decades. ...
Heavy metals are naturally present in earth’s crust, and some of them are essential to living organisms for carrying out life processes. Due to their high persistence and nonbiodegradable nature, heavy metal accumulation beyond recommended concentrations may lead to hazardous effect on various life forms and environment. Contamination of water bodies may be due to natural and anthropogenic sources. Unchecked discharge from industrial sites and agricultural runoff in to adjoining water bodies makes the water unfit for human consumption. Escalating levels of these pollutants pose a threat to aquatic life forms and surrounding environment. Heavy metals can execute various health problems that may range from mild to severe. They can be toxic to living organisms at very low levels of exposure. Excessive usage of heavy metals has raised concerns over time, and consequently, their impact on the overall environment is being studied by researchers extensively. To safeguard human health and environment, proper management and greener technologies for removal of heavy metal from water bodies is required. This chapter will discuss the source, toxicity, and permitted concentrations of some of the major heavy metals in water bodies. Remediation approaches for mitigation of these toxic compounds have also been described. Physical and chemical remediation processes for heavy metal cleanup are highly expensive and sometimes generate a significant amount of secondary pollutants; therefore, the focus has now shifted toward eco-friendly approaches such as bioremediation and phytoremediation. Further research needs to be carried out to maximize the applicability of the existing techniques and developing highly efficient technologies for heavy metal removal from water bodies.
... Pb is a nonessential toxic heavy metal that poses a high risk to human health. Pb is identified as primarily responsible for heavy metal poisoning in children 43 . Chronic exposure to Pb can lead to brain damage, kidney damage, congenital disability, autism, psychosis, paralysis and may cause death 44 . ...
Surface waterbodies being primary source of water for human consumption are being investigated for its quality globally. This study evaluated water quality in three rivers (River Nfifikh, Hassar and El Maleh) of Mohammedia prefecture, Morocco in terms of heavy metals occurrence during two seasons of winter and spring. The heavy metals analyzed were cadmium, iron, copper, zinc, and lead. Heavy metal pollution index was derived to quantify water quality and pollution. Hazard quotient and carcinogenic risk were calculated to determine possible health risk. Modelling and prediction were performed using random forest, support vector machine and artificial neural network. The heavy metal concentration was lower in the winter season than in the spring season. Heavy metal pollution index (H.P.I.) was in the range of 1.5–2 during the winter season and 2–3 during the spring season. In the Nfifikh river, Cd ²⁺ and Fe were the main polluting heavy metal. H.Q. was < 1 in all three rivers, which signified no adverse health effect from exposure to heavy metals. However, carcinogenic risk assessment revealed that 1 in every 100 people was susceptible to cancer during the life span of 70 years. Based on the control point reference, it was found that Mohammedia prefecture as river water was already contaminated before it entered the prefecture boundary. This was again validated with the water lagoon Douar El Marja which is located near the industrial zones of Mohammedia prefecture. Future studies are required to investigate pollution of rivers prior to their entry in Mohammedia prefecture to identify potential source and adopt mitigation measures accordingly.
... Although naturally present in the environment, concentrations of Metallic Trace Elements (MTE) have been increasing over the last decades, due to anthropic activities (Hama Aziz et al., 2023). Considered as indestructible (El Nemr et al., 2016), these contaminants are widely distributed in the environment and can represent risks for both ecosystems (Boyd, 2010;Baby et al., 2011) and human health (Briffa et al., 2020), even at low concentrations in some cases (e.g. lead: Pb, mercury: Hg, cadmium: Cd). ...
This study is a first assessment of Metallic Trace Elements (MTE) contamination of four lagoons in French Polynesia, chosen because their main anthropic uses are potential sources of MTE (military, agriculture, maritime). We used the giant clam Tridacna maxima as a biointegrator of fifteen MTE to assess the environmental footprint of human activities. The study of organotropism showed that not only the kidney but also the gonad and digestive system (GDS) are accumulator organs of interest for ETM biomonitoring. This result confirms that heterotrophic feeding is the pathway of ETM accumulation. Here, T. maxima appeared to be a super-accumulator of Ni (2700 ppm.dw), but also revealed at Tubuai (As, Fe, Mn) and Arutua (Cd, Zn) the environmental footprint of agricultural and maritime activities. The concentration of Cd recorded in Arutua (5 ppm.dw) both in KID and GDS, also underline the need for better control of effluents resulting from human activities.
... [4][5][6][7] Toxic heavy metals in different components of the environment are a severe threat to civilization. 8 Sources may include mining and smelting of ores, electroplating operations, fungicides and pesticides, sewage and sludge from treatment plant etc. [8][9][10][11][12] There are hundreds of sources of heavy metal pollution including industrial waste dumping, burning of fossil fuel, chlor-alkali industries, pulp and paper industries etc. [13][14][15][16][17] These metals may enter into the human body through food, water, air or absorption through the skin when they come in contact with humans in agriculture and in manufacturing, pharmaceutical, industrial or residential settings. Industrial exposure accounts for a common route of exposure for adults. ...
... Nanomaterials (NMs) are currently an intense research area, leading to a broad range of possible applications in the biomedical sector [1,2] agricultural productivity [3], water treatment and remediation [4][5][6]. Industrial waste released into water bodies contain a large amount of dyes and heavy metals which are possible reasons that adversely affect the aquatic organism and humans [7]. The toxic effluent often contains chemicals that are poorly degradable, and highly toxic due to their genotoxic, mutagenic and carcinogenic characteristics [8,9]. ...
... It also affects food production in several ways. It competes with land for food production, degrades agricultural land, pollutes water bodies (Baby et al., 2010), deleterious effects on crops and livestock, and threat to human existence. The Zamfara Pb poisoning due to mining is one sad scenario that cannot be forgotten in the history of Nigeria. ...
Global food insecurity is on the increase, and factors responsible for it are dynamic and differ from country to country. The purpose of this study was to investigate the impacts of security challenges, energy price shocks, and environmental pollution (SEE) on food production, availability, affordability, stability, utilization, and on malnutrition using information from existing literature. Information relevant to the scope of this study was sourced from local Journals, African Journal Online, Science Direct etc. The sourced information deduced that the security challenges in Nigeria had affected (though still affecting) food availability, affordability, and accessibility. While energy price shocks affects negatively, financial access to food especially among the low and medium income Nigerians living in Nigeria. Environmental pollution on the other hand impairs soil fertility and degradation, aquatic animal's extinction, and food safety. The impacts of SEE on food security are enormous and would in no doubt breed more malnutrition especially among children. Also, local, regional, and national security stability and development may be affected. We hope the government and other relevant stakeholders find information in this study impactful and useful, and enable them formulate, propagate, and put to action policies and programs that could in short time thwarts the menaces associated with SEE for a better food secured nation.
... In crustaceans, Cu is a natural component of haemocyanin, the respiratory pigment used in Oxygen transport (Taylor and Anstiss, 1999) [38] . Extensive pollution of various environments has been observed, leading to detrimental effects on the survival and physiological activities of target organisms, as indicated in an investigation conducted by B. Raj, et al, (2010) [1] . ...
Heavy metals, such as copper, are naturally occurring elements with high atomic weight and density, present in trace concentrations in various environmental matrices. However, heavy metal contamination has been on rise in India, affecting industries and agriculture. Copper is one of the most harmful heavy metals, causing adverse effects on human health and aquatic ecosystems. In particular, crustaceans, play crucial roles in aquatic environments but have not been adequately studied. This review aims to explore the impact of copper on aquatic system with special reference to crustaceans and their potential as bioindicators in aquaculture. The origin and sources of heavy metal in water, their toxicity, and effects on fishes and other aquatic organisms are also discussed. Comprehensive research on aquatic bodies and bioindicators is essential to address the challenges posed by heavy metal pollution for sustainable aquatic environments and human well-being.
... 3 Heavy metals are mainly released into the environment with the effluents of many important industries and cause severe risks to the environment and humans simultaneously. 4 Heavy metals, such as copper (Cu), manganese (Mn), lead (Pb), cadmium (Cd), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), chromium (Cr), iron (Fe), arsenic (As), silver (Ag), and platinum (Pt), are toxic and non-biodegradable and, unlike organic pollutants, accumulate in the human body causing health risks. 5,6 The tenacity and persistence in the environment make heavy metals the most serious environmental issue and require special attention. ...
The cost‐effective dual functions zeolite‐carbon composite (DFZCC) was prepared using an eco‐friendly substrate prepared from bio‐waste and an organic adhesive at intermediate conditions. The green synthesis method used in this study ensures that chemically harmless compounds are used to obtain a homogeneous distribution of zeolite over porous carbon. The greenly prepared dual‐function composite was extensively characterized using Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis, N 2 adsorption/desorption isotherms, field emission scanning electron microscope, dispersive analysis by X‐ray, and point of zero charges. DFZCC had a surface area of 248.84 m ² /g and a pore volume of 0.141 cm ³ /g. DFZCC was used in the sorption process of Zn ²⁺ ions from aqueous solutions, and it achieved higher removal (98%) at normal pH of 6.4 and temperature of 40°C. The Langmuir model was the best model for representing equilibrium data with a maximum sorption capacity of 6.711 mg/g. The kinetic studies showed that the pseudo‐second‐order model was the most appropriate model for representing experimental data. The intra‐particle diffusion kinetics demonstrated that the boundary film is the rate‐determining step in the sorption process. The sorption process of Zn ²⁺ ions by DFZCC was spontaneous and endothermic. Moreover, solidification of the spent DFZCC by kaolin successfully reduced the leaching ions to the solution after 12 weeks from exposure to a salty solution.
... They can be seriously harmed by aquatic metal contamination (Ali and US SA, 2014). Toxic metals can be ingested by fish through absorption from various source materials, including contaminants and dissolved metal substances (Baby et al., 2010). These contaminations can endanger fish and pose significant public health issues (Ali and Khan, 2019). ...
Marine hazardous contaminants, such as cadmium (Cd) and lead (Pb), pose significant risks to both human health and aquatic organisms. Traditional methods may not remove contaminants to safe levels, leading to the release of hazardous materials into marine environments. This research proposes polymeric membrane bioreactors as a potential solution to this problem. We determined Cd and Pb levels in three freshwater fish species (Rita, Ompok bimaculatus, and Heteropneustes fossils) from two distinctive regions (Zone 1 and Zone 2). Additionally, Cd and Pb concentrations in feeding materials, water, and sediments were analyzed to estimate daily intake and potential hazardous effects of these contaminants on the fish species. These findings underscore the need for effective regulatory measures and policies to reduce the discharge of hazardous contaminants into freshwater and marine environments, protecting both human health and the environment. Implementing polymeric membrane bioreactors in wastewater treatment and industrial facilities could mitigate the risks associated with consuming contaminated fish species. Significantly, the Cd and Pb levels in all three fish species from both fishponds exceeded the Food and Agriculture Organization's (FAO) maximum permissible limits. These findings carry important implications for policymakers, regulators, and industries, urging them to act appropriately to ensure the safety of the environment and public health. This study suggests that polymeric membrane bioreactors are a promising technological approach to address marine contamination, emphasizing their potential role in safeguarding human health and aquatic ecosystems.
... Among all pollutants heavy metals are of particular concern to the environment and no doubt anthropogenic activities are the main culprit of pollution (Briffa et al., 2020;Balali-Mood et al., 2021). Heavy metals in water are of multiple origins, either from natural sources or from anthropogenic activity such as industrial discharges, sewage discharges, mining, agriculture, marine accidents, shipping traffic, floods, and erosion (Baby et al., 2010;Mirmazloomi et al., 2015;Gheorghe et al., 2017). Some heavy metals in small quantities are essential for biological systems. ...
The present study was undertaken to investigate the antioxidant activity of vitamins C and E singly and together in modulating levels of Malondialdehyde (MDA), total protein, and glucose in different organs (gills, liver, & muscles) and plasma of common carp exposed to heavy metals (Pb, Cd, & Hg). The division of fish into two groups (control group and experimental group) was done after acclimatization. Seven days after exposure to heavy metals, the results showed a significant increase in the level of MDA in all organs of the experimental group (B) compared to those of the control group (A). Metal exposure caused a significant increase in the level of glucose in the liver and plasma (group B), while in muscles and gills, it caused a decrease in the amount of glucose (group B). Heavy metals have caused a slight decrease in total protein (gills, liver, & muscles). Seven days after exposure, the fish were split into three groups: one group was fed with vitamin C, another group with vitamin E, and the third group was fed with both vitamins (C & E). Results show that the addition of vitamins C and E as a food supplement resulted in the restitution of MDA and glucose values similar to those of the control group in all three investigated organs. But in terms of the amount of total protein, the results show that the addition of vitamins (C, E, & C+E) could not restore these values. Otherwise, in most cases, these two vitamins (C & E) administered together have shown more ameliorative effects than in the case of separate administration.
... Bioaccumulation refers to the massing of a material, particularly contamination (including pesticides or toxic metals) in a living creature over time. Such chemicals are rapidly accumulated in living beings and are difficult to digest or eliminate (Joseph et al., 2011). There are abundant freshwater resources in Gilgit Baltistan, like rivers, streams, springs, ponds, and lakes. ...
Heavy metal contamination in surface water is widespread throughout the world as a result of numerous anthropogenic activities and geo-genic mechanisms. This contamination is also affecting aquatic life, as fish have the potential to acquire heavy metals in their tissues making them vulnerable. Worldwide lakes are an important source of water for the inhabitants of the area. So, in the present study, we have focused on the Satpara Lake to check the extent of heavy metal pollution and their accumulation in fish to provide baseline data for metal pollution management. Samples were collected from three locations (inflow, center, and outflow sites) during two seasons (summer and winter). Inductively coupled plasma optical emission spectrometry (ICP-OES) was applied to analyze heavy metals concentration. Among the metals, Cd, Pb, As, and Fe revealed relatively higher concentrations. The highest concentration of heavy metal found in water and fish was of Cd, i.e., 8.87 mg L-1 and 18.19 mg L-1 in summer season, respectively. Arsenic concentration was also higher than the permissible limits in both water (0.76) and fish (1.17 mg L-1). The water quality assessment showed that in the summer season, the HPI (heavy metal pollution index) value 253.01 was more than 100, indicating the bad quality of water for drinking purposes. However, the HPI value 35.72 was less than 100 in winter. Toxicity hazard calculation of fish in summer seasons gives Hi values greater than 10.0, indicating the acute effect on human health as compared to winter.
... In this same line, earlier studies have reported that when crops are grown in soils laden with HMs, the HMs end up in edible parts of the crops [12][13][14][15]. Traces of heavy metals resulting from poor industrial waste disposal have also been reported in fish [16,17], milk [18] and in meat [19,20]. Arsenic was also reported in fodder, with highest concentrations of the element occurring in grasses growing in areas with high As deposits [21]. ...
Poor management of effluents from steel and iron industries could increase element concentrations in the environment and threaten the health of consumers of food products from these areas. The current study assessed element concentration and physicochemical properties of soils, water, and vegetation from within 200 m around three steel and iron industries. A workable grid-based sampling design guided soil and plant sampling; upstream-downstream water quality comparisons were adapted with upstream as a control sample. Analyses were conducted following procedures by USEPA method 3051A. Element concentration was in the order Mn>As>Zn>Cr>Pb. The concentrations reduced with increase in distance from the industry. There was moderate-to-strong pollution of soils for As, and transfer factor for all elements was >1. In conclusion, industrial activity might have contributed to increased element concentrations in the soils, vegetation, and water sources around the industries. Agrarian activities may only be safely carried out 151m away from the industries.
... In recent decades, worries have been raised about the increasing concentration of pollutants in freshwater sources. Heavy metals discharged from homes, factories, mines, and other human activities may have widespread impacts on aquatic ecosystems [49][50][51][52][53]. ...
A worldwide contaminant that has an impact on environment and human health is mercury (Hg). We combine knowledge of sources, dynamics of atmosphere land ocean Hg and health impacts while taking into account the effects of Hg control measures. This study's goal is to provide a thorough analysis of the Hg literature in relation to effects on wildlife especially understudied species. This article demonstrates how the context of Hg exposure in the environment plays a significant role in determining the likelihood of exposure and adverse health effects. In order to identify gaps in knowledge and plan future research necessary to conduct a thorough assessment of Hg dangers to wildlife, we give a critique of the existing state of knowledge about effects of Hg on wildlife. A wide variety of clinical manifestations can be brought on by mercury. Mercury toxicity can be difficult to diagnose although it is possible to do so with some degree of confidence. Clinical toxicity treatments with good success rates have been identified. The context of Hg exposure in the environment is an important factor that affects the likelihood of exposure and negative health outcomes, as this article reveals. The development of context-dependent assessments in the future will enable better risk estimations for both people and wildlife. This review article presents many recent works, including both original and review papers, that provide an overview of mer-cury's toxicity to humans and the environment.
For the health of humans, soil, and aquatic life, cadmium is a hazardous, non-essential metal. In the microbes of soil and soil ecology, cadmium has a deleterious impact. Additional harmful consequences of cadmium for people Cadmium causes poor bone mineralization, which raises the risk of osteoporosis and bone fractures. Furthermore, it produces bone-related nerve discomfort. The corrosive resistance of cadmium is good, and it stabilizes polyvinyl chloride. In fish, exposure to cadmium reduces growth rate and causes pathophysiological harm. Continuous exposure harms larvae and slows their rate of development. Fluid replacement, supplementary oxygen, and mechanical breathing may be helpful if cadmium toxicity develops. Gastric lavage is also helpful after exposure.
Worldwide, the harmful ion contamination of water has become a serious problem because of unregulated industry, energy production, and mining, which greatly increase the concentration of pollutants in water. The novel membranes through adsorbent self-assembly, such as protein amyloids, were explored for wastewater treatment. Herein, we report amyloid fibril (AF)-embedded bacterial cellulose nanohybrid membrane for efficient removal of heavy metal from industrial effluent. AFs are synthesized by heat treatment using bovine serum albumin and embedded with bacterial cellulose nanomembrane (BCN). The AF-embedded BCN (AF/BCN) was characterized using microscopy and spectroscopic methods. In addition, the well-ordered multi-layered AF/BCN filtration assembly was fabricated in the commercial cartridge and validated for the removal of heavy metals (Pb2+ and Hg2+) from wastewater and treatment of industrial wastewater sample containing heavy metals. Our multi-layered filtration assembly removed Hg+2 and Pb+2 with efficiency of 95 and 78.34%, respectively. A computational study using molecular docking has also been performed for the identification of metal entrapment sites. Moreover, our AF/BCN filtration assembly showed high regeneration capacity up to four cycles. The isotherm model also revealed a strong fit and good adsorption behaviour. This makes potential filtration assembly for low-cost, high-efficiency for the removal of HM from wastewater.
Artificial superhydrophobic surfaces that do not absorb water, like the lotus leaf, show tremendous promise in numerous applications. However, superhydrophobic surfaces are rarely used because of their low stability and...
Recently, the integrated different interdisciplinary studies derived the environmental solutions of the climate change impacts (e.g., cultivation, wastewater treatment, and managing groundwater resources) (Mesalhy et al. 2020, and Gobashy et al. 2021). Thus, this paper focused on the application of bioremediation to maximize the use of wastewater for new reclamation areas in the Northwest Egyptian desert (New Egyptian Delta (NED). In the NED project, the drainage water samples collected from Nile Delta drains will provide the main unconventional water resources for irrigation through the new Hammam canal. Therefore, three Pleurotus strains were grown moderately on two natural media, the first containing Salvia L. (sage) extract (MDA) and the second containing Thymus vulgaris L. (origanum thymus Kuntze, Thymus collinus Salisb) (TDA) extract replacing potato infusions in standard PDA. Pleurotus ostreatus (Jacquin; Kummer) strain records the highest growth among the three tested fungi on modified media. PO records 4.49 and 4.41 cm on (MDA) and (TDA), respectively. There is a marked decrease in the majority of heavy metal concentrations on sterile drainage water amended with PD broth and inoculated with three tested Pleurotus strains individually. At the end of the incubation period, Pleurotus ostereatus which expressed in abbreviation (PO) are more efficient in the removal of Al, Co, Cr, and Ni by 53.15, 95.87, 58.47, and 85.07%; respectively. Pleurorotus pulmonarius (Fr.) which symbolized (PP) is more potent in the removal of Cd, Si, Sn, Sr, and V by 70.37, 56.59, 41.19, 52.78, and 96.24%; respectively. Pleurotus floridanus (NZOR) which indicated as (PF) is actively over the former species in the removal of Ba, Fe, and Mo by 87.84, 46.67, and 97.34%; respectively. Cu, Mn, Pb, As, and Se could not be detected as the control sample recorded measurements below 0.009 mg L⁻¹. An unexpected increase in Zn among the different treatments was detected from 05.04 to 07.01%.
Carbon nanodots (CNDs) as an emerging and new class of nanomaterials have been widely used as sensing probes for metal cations based on fluorescence quenching. Several precursors have been utilized as starting materials for the synthesis of CNDs, either natural, artificial, or waste materials. Herein, we present a new precursor and cost-effective method to synthesize CNDs aligning with circular economy and green chemistry principles. Two classes of CNDs were obtained, starting from used (smoked) tobacco molasses, through two processes. First, extraction was directly carried out on molasses residue to isolate one class of CNDs, i.e. D-CNDs; then the residual solid was treated by chemical oxidation, yielding a different population of CNDs, named O-CNDs. Synthesized CNDs exhibited different properties in terms of size, functional groups, and optical properties. These features lead to different sensing abilities toward Fe3+ cation. O-CNDs showed better results in terms of sensitivity (0.0045 μM−1), limit of detection (LOD = 3.9 μM), and limit of quantification (LOQ = 13 μM) compared to D-CNDs (Sensitivity = 0.0029 μM−1, LOD = 7.2 μM, and LOQ = 24 μM). The quenching mechanism attained in both CNDs is due to a combined static-dynamic effect in which the static is the dominant component. Therefore, the synthesized O-CNDs could serve as promising and low-cost nanomaterials for selective sensing of Fe3+ cation in contaminated water.
Background
Red meat from livestock is an excellent source of high-quality protein, vitamins, and minerals.
Objective
This meta-analysis aimed to investigate the levels of two of the most toxic heavy metals; lead (Pb) and cadmium (Cd) in meat and edible offal (liver and kidney) of livestock (sheep, buffalo, and cow) in Iran with assessing their health risk of developing cancer.
Methods
A systematic search was conducted covering ISI Web of Science, PubMed, and Google Scholar. Finally, data from 4 articles including 624 samples were analysed
Results
Pooled results show that the mean concentrations of Pb and Cd were 0.18 mg/kg and 0.13 mg/kg respectively which were both higher than their eligible maximum limits by FAO/WHO. The Estimated Daily Intake (EDI) of Pb and Cd in meat, liver, and kidney for adults and children was lower than the Total Daily Intake (TDI) limits. The consumers' non-carcinogenic risk (THQ) for meat consumption was generally safe in terms of Cd and Pb in all cities except for Pb in Hamadan which was greater than one (unsafe) for both adults and children. Carcinogenic Risk (CR) for meat consumption was generally safe or within the acceptable range in terms of Cd and Pb in all cities except for Pb in Hamadan which had a Pb-CR greater than safe/permissible level for children.
Conclusion
It can be concluded that the dangerous levels of CR and THQ of meat in terms of Pb in Hamadan warrant concern and further study.
Bu çalışmada, modern davul setlerinde yaygın olarak kullanılan sentetik davul derileri, yapısal farklılıklar açısından incelenmiştir. Sentetik davul derileri, yapısal olarak temelde tek kat ve çift kat olmak üzere iki ana kategoriye ayrılmaktadır. Bu çalışma, bu temel fiziksel yapısal farklılıkların tınısal etkilerini, STFT (Short-Time Fourier Transform) ve Welch yöntemleri kullanılarak analiz etmeyi amaçlamaktadır. Yapılan tınısal analizler sonucunda, tek kat ve çift kat sentetik davul derileri arasındaki bu temel fiziksel yapısal farklılıkların ses üzerindeki etkileri sistematik bir şekilde ortaya konulmuştur. Bu bulgular, davul sesi kalitesi ve performansı üzerine önemli etkileri olan yapısal özelliklerin daha derinlemesine anlaşılmasına katkı sağlamaktadır.
Coastal marine waters in the Gulf of Guinea are severely affected by heavy metal pollution, particularly from small scale mining activities around major rivers feeding estuaries in the Region. However, the potential impact of these environmental stressor on the productivity of planktonic organisms remain unknown. We quantified survival, reproduction and faecal pellet production rate of calanoid copepods – Temora stylifera and Centropages velificatus, commonly found in coastal marine waters of the Gulf of Guinea – after culturing in seawater containing cadmium (proxy for toxic metals) at five concentrations (0.0, 0.05, 2, 20, 200 and 200 + µg.L− 1) for 24 h. Increasing exposure to cadmium resulted in reduced survival and egg production, in general agreement with reports on species from other large marine ecosystems. Acute toxicity (expressed as 24-hour LC50) of the metal was positively related to the size (dry weight) of the copepods, with increased severity in C. velificatus. We estimate that the maximum cadmium concentration (3–5 µg.L− 1) currently prescribed for coastal marine waters in West Africa is higher (≥ 40%) than the concentration (0.36–1.20 µg.L− 1) that triggers the acute toxicity of the metal. We therefore recommend a review of the water quality criteria for managing coastal marine ecosystems of the Region.
Heavy metals are metallic elements with a high density compared to water that are found in trace amounts in a variety of matrices. Mercury poisoning can cause brain damage, skin damage, and increase risk of cancer development. Mercury-poisoned animals cannot produce meat, liver, or kidneys fit for human consumption. Heavy metals can cause cell dysfunction and toxicity by attaching to protein sites and displacing the original metals from their native binding sites. Reducing input/output ratio of heavy metals in animals should be the main objective of effective solutions. Electro-remediation involves running an electric current through liquid manure to cause metal ions to precipitate on an electrode.
The chapter describes the occurrence, exposure and harmful effects of heavy metals on human health and aquatic environment. This chapter also discusses their metabolic element, primary entry points, and the relative size of such instances. Eventually, heavy metals put the living things under a lot of stress, which raises mortality. As a result, this study comments on and clarifies how heavy metal exposure to aquatic food affects human health risks. In many places of the world, the main instances are mostly associated with the negative effects of mercury, lead, arsenic and other heavy metals on human health. Last but not least, remediation is advised to bring about stability in aquatic ecosystems and human health.
Recently the integrated different interdisciplinary studies derived the environmental solutions of the climate change impacts (e.g., cultivation, wastewater treatment, managing groundwater resources). Thus, this paper focused on the application of bioremediation to maximize the use of wastewater for new reclamation areas in the Northwest Egyptian desert (New Egyptian Delta (NED). In NED project, the drainage water samples collected from Nile Delta drains will provide the main unconventional water resources for irrigation through the new Hammam canal.
Therefore, three Pleurotus isolates were grown moderately on two natural media, the first containing Salvia extract (MDA) and the second containing Thymus (TDA) extract replacing potato infusions in standard PDA. Pleurotus ostreatus (P.O) isolate records the highest growth among the 3 tested fungi on modified media. PO records 4.49 and 4.41 cm on (MDA) and (TDA); respectively. There is a marked decrease in the majority of heavy metals concentrations on sterile drainage water amended with liquid PDA broth and inoculated with three tested Pleurotus isolates individually. At the end of the incubation period, Pleurotus ostereatus are more efficient in the removal of Al, Co, Cr, Ni by 53.15, 95.87, 58.47, 85.07%; respectively. Pleurorotus pulmonarius (P.P) is more potent in the removal of Cd, Si, Sn, Sr, and V by 70.37, 56.59, 41.19, 52.78, 96.24%; respectively. Pleurotus floridanus (P.F) is actively over the former species in the removal of Ba, Fe, Mo by 87.84, 46.67, 97.34%; respectively. Cu, Mn, Pb, As, Se couldn’t be detected as the control sample recorded measurements below 0.009 mg L⁻¹. Unexpected increase in Zn among the different treatments was detected from 05.04% to 07.01%.
Objective.
—To describe trends in blood lead levels for the US population and selected population subgroups during the time period between 1976 and 1991.
To describe trends in blood lead levels for the US population and selected population subgroups during the time period between 1976 and 1991.
Two nationally representative cross-sectional surveys and one cross-sectional survey representing Mexican Americans in the southwestern United States.
Participants in two national surveys that included blood lead measurements: the second National Health and Nutrition Examination Survey, 1976 to 1980 (n = 9832), and phase 1 of the third National Health and Nutrition Examination Survey, 1988 to 1991 (n = 12,119). Also, Mexican Americans participating in the Hispanic Health and Nutrition Examination Survey, 1982 to 1984 (n = 5682).
The mean blood lead level of persons aged 1 to 74 years dropped 78%, from 0.62 to 0.14 mumol/L (12.8 to 2.8 micrograms/dL). Mean blood lead levels of children aged 1 to 5 years declined 77% (0.66 to 0.15 mumol/L [13.7 to 3.2 micrograms/dL]) for non-Hispanic white children and 72% (0.97 to 0.27 mumol/L [20.2 to 5.6 micrograms/dL]) for non-Hispanic black children. The prevalence of blood lead levels 0.48 mumol/L (10 micrograms/dL) or greater for children aged 1 to 5 years declined from 85.0% to 5.5% for non-Hispanic white children and from 97.7% to 20.6% for non-Hispanic black children. Similar declines were found in population subgroups defined by age, sex, race/ethnicity, income level, and urban status. Mexican Americans also showed similar declines in blood lead levels of a slightly smaller magnitude over a shorter time.
The results demonstrate a substantial decline in blood lead levels of the entire US population and within selected subgroups of the population. The major cause of the observed decline in blood lead levels is most likely the removal of 99.8% of lead from gasoline and the removal of lead from soldered cans. Although these data indicate major progress in reducing lead exposure, they also show that the same sociodemographic factors continue to be associated with higher blood lead levels, including younger age, male sex, non-Hispanic black race/ethnicity, and low income level. Future efforts to remove other lead sources (eg, paint, dust, and soil) are needed but will be more difficult than removing lead from gasoline and soldered cans.
To determine mean blood lead levels and their sociodemographic correlates in the US population.
Nationally representative cross-sectional health examination survey that included measurements of venous blood lead.
A total of 13,201 persons aged 1 year and older examined during phase 1 of the third National Health and Nutrition Examination Survey (1988 to 1991).
The overall mean blood lead level for the US population was 0.14 mumol/L (2.8 micrograms/dL). Blood lead levels were consistently higher for younger children than for older children, for older adults than for younger adults, for males than for females, for blacks than for whites, and for central-city residents than for non-central-city residents. Other correlates of higher blood lead levels included low income, low educational attainment, and residence in the Northeast region of the United States. National estimates for children 1 to 5 years of age indicate that 8.9%, or approximately 1.7 million children, have blood lead levels 0.48 mumol/L (10 micrograms/dL) or greater. These levels are high enough to be of health concern under 1991 Centers for Disease Control and Prevention guidelines.
The low overall mean blood lead levels demonstrate a major public health success in primary prevention efforts. However, exposure to lead at levels that may adversely affect the health of children remains a problem especially for those who are minority, urban, and from low-income families. Strategies to identify the most vulnerable risk groups are necessary to further reduce lead exposure in the United States.
The literature on the speciation of arsenic (As) in seafoods was critically reviewed. Most research has been directed toward fresh seafood products with few papers dealing with As speciation in manufactured seafoods. Predictions concerning As species made on the basis of fresh seafood products cannot be extrapolated to manufactured seafoods. Therefore, due to the numerous species of As, the scarcity of data concerning their presence in foods, the transformations each species may undergo during industrial processing and cooking, and the lack of legislation on permitted As levels in seafood products, As species in manufactured seafood products need to be determined and quantified.
Levels of Zn, Cu, Cd, As, and Pb in the kidney, Liver, Gills and Heart of African cat fish (Clarias gariepinus) from the Ogun River in Ogun State located close to six major industries in the South Western part of Nigeria, were determined using Bulk Scientific Atomic Absorption Spectrophotometer. Fishes were also collected from Government owned fish farm in Agodi, Ibadan which was considered a reference site. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione (GSH) concentration and malondialdehyde (MDA) formation were also determined. The trend of accumulation of the metals in the organs is as follows: Heart - Zn > Cu > Pb > As > Cd; Gills - Zn > Cu > Pb > Cd > As; Kidney - Zn > Cu > Pb > As > Cd; Liver -Zn > Cu > Pb > As > Cd. The order of concentration of the metals in the organs is as follows: Arsenite - Kidney > Liver > Gills > Heart; Zinc - Gills > Liver > Kidney > Heart; Lead- Liver > Kidney > Gills > Heart; Copper- Kidney > Liver > Gills > Heart; Cadmium > Liver > Gills > Kidney > Heart. The levels of heavy metals ranged between 0.25-8.96 ppm in the heart, 0.69- 19.05 ppm in the kidneys, 2.10-19.75 ppm in the liver and 1.95-20.35 ppm in the gills. SOD activity increased by 61% in the liver, 50% in the kidney and in the heart by 28 % while a significant decrease (44%) was observed in the gill of Clarias gariepinus from Ogun river compared to that Agodi fish farm (P
This article describes the health effects of the two principal forms of mercury to which humans are exposed, namely mercury vapor and methylmercury compounds. Mercury vapor is the monatomic gas that vaporizes from liquid metallic mercury. It has a long history of human exposure dating back to ancient times. The earliest life forms on this planet may have received substantial exposure and developed defense mechanisms that we inherit to this day. Severe forms of poisoning from inhalation of mercury vapor are now rare. More commonly observed in occupational exposures are subtle neurobehavioral effects and preclinical changes in biochemical markers of kidney function.
It is well known that the progressive acidification of the lakes in Canada as well as United States and Scandinavia, has reduced drammatically the fish production in these natural areas. This phenomenon, due to acid rain, could lead to very low pH values ranging between 4.5 and 4.0. Similar decrease in pH (4.7) has been found in several rivers of Nova Scotia, once teeming with salmon, and in other remote areas of Muskoka (Ontario). Moreover, water acidification may occur even in spring, when a large amount of acid water reaches the lakes after the melting of the snow. The pH then drops to 5.5, which is particularly harmful to small fish.
Hg has been measured using ultraclean procedures in snow deposited in central Greenland from 1949 to 1989. Concentrations range from ≤0.05 to 2.0 pg/g (mean : 0.43 pg/g), i.e. values which are orders of magnitude lower than those obtained in earlier studies. It indicates that earlier data were plagued by major contamination problems. Combined estimated contributions from natural Hg sources cannot explain Hg concentrations observed in the snow. It suggests that Hg deposition to the Greenland ice sheet is now significantly influenced by anthropogenic inputs from North America, Asia and Europe linked especially to coal burning and solid waste incineration. Although our data suggest that Hg concentrations were higher in snow dated from the late 1940s to the mid 1960s than in more recent snow, further studies are needed to clearly assess Hg temporal trends.
1.1. The injection of adrenaline or dibutyril cyclic AMP to rainbow trout, Salmo gairdneri was followed by an increase in blood glucose and lactate.2.2. The injection of glucagon was followed by hyperglycemia without increase in blood lactate.3.3. None of these treatments produced significant alterations in liver glycogen.4.4. The simultaneous injection of dibutyril cyclic AMP and α-cyano-hydroxy-cinnamate resulted in a substantially smaller increase in blood glucose concentration than the injection of dibutyril cyclic AMP alone.5.5. These results show that hyperglycemia was due to gluconeogenesis under these circumstances, confirming the key role of this process in the trout.
A cohort of 1022 consecutive singleton births was generated during 1986–1987 in the Faroe Islands. Increased methylmercury exposure from maternal consumption of pilot whale meat was indicated by mercury concentrations in cord blood and maternal hair. At approximately 7 years of age, 917 of the children underwent detailed neurobehavioral examination. Neuropsychological tests included Finger Tapping; Hand–Eye Coordination; reaction time on a Continuous Performance Test; Wechsler Intelligence Scale for Children—Revised Digit Spans, Similarities, and Block Designs; Bender Visual Motor Gestalt Test; Boston Naming Test; and California Verbal Learning Test (Children). Clinical examination and neurophysiological testing did not reveal any clear-cut mercury-related abnormalities. However, mercury-related neuropsychological dysfunctions were most pronounced in the domains of language, attention, and memory, and to a lesser extent in visuospatial and motor functions. These associations remained after adjustment for covariates and after exclusion of children with maternal hair mercury concentrations above 10 μg/g (50 nmol/g). The effects on brain function associated with prenatal methylmercury exposure therefore appear widespread, and early dysfunction is detectable at exposure levels currently considered safe.
The objective of this study was to characterize the metal binding of the external gill surface in an attempt to interrelate metal chemistry, gill surface binding activity, and possibly metal toxicity. Individual gill arches from adult rainbow trout (Oncorhynchus mykiss) were exposed to various concentrations of either 140La, 45Ca, 109Cd, or 64Cu. The apparent dissociation constant (KD) and capacity (Bmax) of the external gill surface for the metals was calculated using Scatchard plot analysis. Half-saturation time (t1/2) and binding cooperativity (Hn) were also determined. The KD for gill metal binding ranged from 0.31 ± 0.02 mM for La3+ (high affinity) to 4.3 ± 0.04 mM for Cu2+ (low affinity). The gill binding affinity for Ca2+ was threefold lower than for La3+, but was similar to that for Cd2+. The gills had the lowest affinity for Cu2+, almost 14 times lower than that for La3+. Bmax for La3+ was found to be significantly lower than for any other metal (0.14 ± 0.001 μmol∙g−1), while nearly seven times as much Cu2+ was accumulated by the gills compared with La3+, The Ca2+ and Cd2+Bmax estimates were intermediate.
Fish and zooplankton were simultaneously exposed to trace, 1, and 5 μg Hg/L. In fish and zooplankton, pathological effects appeared to coincide with saturation of metallothionein and "spillover" of Hg into the high molecular weight protein (enzyme-containing) pool. Coincidental with increases of Hg in tissue were decreases of Cu and Zn. Pathological effects of Hg are explained in terms of tertiary and quaternary structural changes in metalloenzymes resulting from replacement of Cu and Zn by Hg. Decreases in tissue Cu and Zn with increasing Hg concentration are discussed as an intracellular displacement of Cu and Zn by Hg and as duodenal and cellular exclusion processes. Key words: CEPEX, Oncorhynchus keta, zooplankton, mercury, copper, zinc, metallothionein, enzymes, metal tolerance
It is proposed that the term ‘heavy metals’ be abandoned in favour of a classification which separates metal ions into class A (oxygen-seeking), class B (nitrogen/sulphur-seeking) and borderline (or intermediate). A survey of the co-ordination chemistry of metal ions in biological systems (mostly X-ray crystallographic data) demonstrates the potential for grouping metal ions according to their binding preferences (i.e. whether they seek out O-, N- or S-containing ligands). This classification is related to atomic properties and the solution chemistry of metal ions. A convenient graphical display of the metals in each of the three categories is achieved by a plot of a covalent-bonding index versus an ionic-bonding index. A review of the roles of metal ions in biological systems demonstrates the potential of the proposed classification for interpreting the biochemical basis for metal-ion toxicity and its use in the rational selection of metal ions in toxicity studies.
1. We have assessed, using current literature, the respiratory consequences of water-borne heavy metal exposure in crustaceans and molluscs.2. We suggest that in lethal and sub-lethal concentrations the essential metals Cu and Zn act on the respiratory system primarily by disrupting gill function which results in the development of internal hypoxia, although reparation can be accomplished even at “high” sub-lethal concentrations.3. The more toxic xenobiotes such as Hg (and perhaps to a lesser extent Cd) may interfere with the respiratory system at every level of organisation including cellular respiration itself.
Proton uptake by intact algal cells was found to consist of two processes: (1) a fast (<4 s) surface reaction and (2) a slow (2 h) diffusion of protons into cells. A pH titration technique measured only the rapid surface reaction that forms negative sites at higher pH. Adsorption of alkali, alkaline earth, and transition metal ions on algae was quantitatively represented by the Langmuir adsorption isotherm with its two parameters γ(m), the maximum amount of metal adsorbed, and K, the equilibrium constant taken as a measure of bond strength. Variations of these parameters with pH and type of metal indicate that metals adsorb to algal surfaces by electrostatic attraction to negative sites, such as carboxylate anions of poly(galaturonic acid) (pectin), as previously suggested.
This broad-scale investigation provides an overview of trace metal concentration and distribution within sediments in the subtropical setting of Moreton Bay on the eastern Australian coast. Samples of sediment in one-metre long PVC cores were collected from the intertidal zone of the western shoreline of the Bay and within its main estuaries. The material is typically silty sand along the Bay shoreline, becoming more clayey within the estuaries.
Downcore pH is typically between 7.0 and 8.0, with layers in some cores of pH 6.0 to 7.0. Locally, pH can fall below 5.0 due to pyrite oxidation or exceed 8.0 due to the presence of shell fragments.
A comparison with results of similar studies in other highly populated centres in Australia shows that overall the Moreton Bay area sediments have relatively low metal content. Typically, concentrations are two to three times higher in fine-grained, estuarine sediments than in sandy material along the Bay shoreline. Compared with Australian and New Zealand Environment and Conservation Council Guidelines for metal concentrations in sediments, the elements most commonly elevated and warranting further assessment are Ni, Hg, Pb, Zn, and occasionally Cd, As and Cr. The highest metal concentrations are found in estuaries, close to more populated or industrialised areas, notably along the Brisbane River.
Overall, the distribution of metals in unconsolidated material is controlled by (a) the heavy metal affinity for Fe- and Mn-rich oxidised sediments, (b) grain size, (c) background concentrations in local rocks, and (d) conditions of weathering and deposition. For example, natural elevation of Fe occurs in marine sediments adjacent to areas of Tertiary basalts and this has produced a relative increase in a number of trace metals in those sediments.
Typically, trace metals correlate well with Al, and with Fe and Mn oxyhydroxides. The results of this study show that in the western Moreton Bay region, natural controls have the major influence over metal distribution; although urban and industrial inputs exist, for much of the area they are secondary. The main sources of introduced trace metals are presumed to be light industry (such as maritime and port facilities, petroleum refineries and storage, manufacturing and chemical processes), landfills, agriculture and intensive fertilising (for example, golf courses) as well as the composite effect of urban centres. Overall, higher concentrations of metals are closely related to intense development. If specific locations are targeted for focussed sampling, elevated concentrations of metals are likely to be found locally.
The binding affinity of winter flounder plasma proteins for zinc was determined by equilibrium dialysis. The relationship between the percentage of zinc bound and the total zinc present in the system produced a curved line. A Rosenthal type plot indicated that there was more than one binding system for zinc present. The association constant computed from the first slope, 107–108, compared with that of mammalian serum albumin. It required twice the normal total plasma zinc concentration to saturate the higher affinity binding system.All of the plasma zinc could be removed by dialyzing with 10−2M histidine.The specificity of the plasma proteins for binding zinc was studied by introducing the following cations: Cu2+, Cd2+, Ca2+, Mg2+, Co2+, Mn2+, Hg2+, Fe2+, Cr2+, and Ni2+. Only Cu2+ competed significantly with the binding of zinc to the plasma. This competitive effect was diminished in the presence of Tris buffer.Studies in the presence of EDTA indicated that the EDTA had a greater effect on the zinc binding than would be predicted from its theoretical binding capacity for zinc.
1. The bioconcentration of atrazine, zinc and iron in the blood of Tilapia sparrmanii has been determined separately in each of six exposure groups. 2. An increased bioconcentration of atrazine in the blood occurred with an increased exposure concentration. 3. With exposure to zinc, there was a gradual decrease in bioconcentration of zinc in the blood of T. sparrmanii with an increased concentration in the water. 4. A similar tendency was observed during iron exposure, except that the decrease in bioconcentration was not significant.
1. Channel catfish (Ictalurus punctatus) have a remarkably high concentration of zinc (Zn) in their blood serum, about 20 micrograms/ml. However, compared to mammals, the concentrations of Zn in their tissues are not remarkable. The serum Zn is dialyzable against a solution containing 1 mM EDTA. 2. Following separation of serum proteins by gel-filtration most of the Zn was recovered in a fraction with the same peak volume of elution for the Zn and protein concentrations and having a molecular weight similar to bovine serum albumin. 3. Binding of Zn to such sites was not changed by Cu2+, Cd2+, Ca2+, or La3+. N-ethylemaleimide (NEM) appeared to decrease binding slightly. 4. Equilibrium dialysis with a Scatchard plot analysis of these data suggested that a single set of binding sites was present on the protein(s) with KD of 2 x 10(-5) M. There were binding sites for 35 x 10(-8) M Zn/mg protein. 5. Parallel equilibrium dialysis measurements using human, rabbit and chicken albumins indicated that the catfish serum protein(s) had a much higher affinity and binding capacity for Zn than the albumins in these species. 6. The catfish Zn serum-binding protein may be an albumin. The possible physiological significance of such a serum protein in freshwater fish is discussed.
The direct effects of epinephrine and norepinephrine (NE) on lipid mobilization were studied in coho salmon liver slices incubated in vitro. Fatty acid (FA) release from liver slices was measured continuously by pH-stat titration. The pH-stat assay system was validated by simultaneous colorimetric measurement of FA and glycerol release. Liver slices incubated in a glucose-free, low buffering capacity medium and stimulated with NE (10(-6) M) exhibited a one proton (titrimetric) to one FA (colorimetric) release profile. Under similar conditions, NE administration also stimulated glycerol release, in the expected three FA (colorimetric) to one glycerol (colorimetric) ratio. NE stimulated FA release from liver slices in a dose-dependent manner; epinephrine did not have a lipolytic effect. The beta-agonist isoproterenol stimulated FA release, whereas alpha-agonists had no effect. Furthermore, the beta-antagonist propranolol inhibited both NE- and beta-agonist-stimulated FA release. Liver triacylglycerol lipase activity was also stimulated by NE. Propranolol inhibited NE-stimulated lipase activity. These results establish the presence of hormone-sensitive lipase in salmon liver and suggest that NE-stimulated lipid mobilization in salmon liver is mediated through beta-adrenergic pathways.
In rat jejunal mucosa cells, Cd bound to the outside of the brush border can be distinguished from internalized Cd by its reaction with extracellular chelators; internalized Cd is only released after destruction of the cell. Similar results have been obtained with rabbit erythrocytes and resealed ghost cells. A temperature-dependent process carries Cd from the EDTA-sensitive into the EDTA-insensitive compartment. In enteric cells, only 1/3 of the external binding sites permit subsequent internalization. EDTA does not remove Hg from cell ligands, but internalized Hg can be distinguished from externally bound Hg with the help of dimercaptopropanol; internalization of Hg bound to active membrane sites must be relatively rapid. Internalization of Cd and Hg by ghost cells and by isolated membrane vesicles, as described elsewhere, suggests that the process is independent of pinocytosis. The results therefore support a previously suggested model describing the movements of non-essential and poisonous metals across cell membranes in terms of a non-specific binding step, followed by what may represent the activity of mobile carriers.
Cutaneous mercury granulomas are rarely encountered. Clinically they pose difficulty in diagnosis when there is no clear history of penetrating injury by objects containing metallic mercury. Histologic, chemical, and scanning electron microscopic studies of such cutaneous lesions were performed on four cases from the Armed Forces Institute of Pathology files. Reported cases from the literature were reviewed. Metallic mercury in tissue sections appears as dark, opaque globules, usually spherical in shape and of varying sizes and numbers. A zone of collagen necrosis often surrounds the mercury globules. A granulomatous foreign body-giant cell reaction and a mixed inflammatory cellular infiltrate composed of neutrophils, lymphocytes, histiocytes, plasma cells, and occasional eosinophils are usually present. Epidermal and dermal necrosis, with or without ulceration or pseudoepitheliomatous hyperplasia, is also a common finding. The gold lysis test and energy-dispersive x-ray analysis confirmed the presence of metallic mercury in the tissue. Following cutaneous injury from mercury, systemic toxicity may develop and death may even occur. An approach to clinical management is discussed.
The chemical contamination of foods via industrial activity is varied and widespread with regard to both chemical and occurrence. Such contamination can arise by accident, by intent from regular ongoing industrial activity, and even from subsequent use of manufactured products themselves. The key factors in assessing whether a problem exists within a particular country are recognition and awareness that a problem can exist and the capability to define the extent and severity of the problem. Both factors are heavily dependent on the availability of well-equipped food control laboratories staffed by dedicated and competent personnel. In some situations the analytical techniques required are 'state of the art' involving sophisticated and expensive separations and determinations with extensive quality control procedures. In others, the techniques are much less complicated. In both, however, the production of valid data is paramount. To illustrate some of these differences in approach, details of ongoing Canadian programmes on polychlorinated dibenzo-dioxins and -furans in effluents from pulp and paper mills and on the migration of chemicals from packaging materials are presented.
New Delhi--A potentially devastating health crisis is quietly unfolding in West Bengal, India, where high levels of arsenic have leached into well water and have put more than a million Indians at risk. The immense scale of the human tragedy has begun to attract the attention of scientists from around the world, who see in this grim event an unprecedented chance to learn more about the health effects of arsenic, a known carcinogen. “We're talking about numbers [of arsenic-poisoning victims] that have never been seen before in the world,” says University of California, Berkeley, epidemiologist Allan Smith.
The purpose of this study was to determine the relationships of lead content in the human tooth with the prevalence of caries, dental plaque, pH of saliva, levels of Salivalis lactobacilli (SL) and Mutans streptococci (MS), degree of dental abrasion, tooth colour and toothbrushing frequency. A total of 220 teeth (one per person) were analysed using a microwave oven digestion procedure and lead content was measured by atomic absorption spectrometry. Tooth lead content followed a logarithmic-normal distribution and it increased with the prevalence of caries. Tooth lead concentrations were positively correlated with all the considered dental health factors except the pH of saliva, for which there was a significant negative correlation. Coloured teeth and teeth subject to abrasion showed the highest lead content. The highest number of colonies of SL and MS in saliva paralleled the highest lead tooth levels. Teeth obtained from irregular brushers presented higher tooth lead contents than subjects with a regular toothbrushing frequency. Multiple logistic regression analysis showed a significant association between tooth lead levels and dental plaque surface, Salivalis lactobacilli number, dental abrasion and dental colour. We conclude that accumulation of lead in teeth is associated with those dental health factors.
Injury and poisoning from metallic mercury has become a rare event. Review of the literature and a case report of pediatric metallic mercury injury are presented.
A case report.
The Emergency Department at St. Louis Children's Hospital.
A 15-year-old boy.
None.
None.
The 15-year-old boy fell on a broken mercury thermometer. A subcutaneous abscess formed on his left forearm during the next five days. He had no signs or symptoms of mercury toxicity. His wound was debrided in the operating room and healed completely after several months.
This case shows elemental mercury from a thermometer as a potential, if unusual, source of mercury toxicity.
The focus of the present study was on the relationship between Hong Kong male subfertility and fish consumption. Mercury concentrations found in the hair of 159 Hong Kong males aged 25-72 (mean age = 37 years) was positively correlated with age and was significantly higher in Hong Kong subjects than in European and Finnish subjects (1.2 and 2.1 ppm, respectively). Mercury in the hair of 117 subfertile Hong Kong males (4.5 ppm, P < 0.05) was significantly higher than mercury levels found in hair collected from 42 fertile Hong Kong males (3.9 ppm). Subfertile males had approx. 40% more mercury in their hair than fertile males of similar age. Although there were only 35 female subjects, they had significantly lower levels of hair mercury than males in similar age groups. Overall, males had mercury levels that were 60% higher than females. Hair samples collected from 16 vegetarians living in Hong Kong (vegans that had consumed no fish, shellfish or meat for at least the last 5 years) had very low levels of mercury. Their mean hair mercury concentration was only 0.38 ppm.
The average person in Hong Kong consumes fish or shellfish four or more times a week averaging about 60 Kg of fish per year. Even though the mean mercury level in store-bought Hong Kong fish was only 0.12 mg/kg, corroborating evidence is presented from numerous studies to support the view that mercury bioaccumulates. By the time a typical Hong Kong male reaches 30 years of age he will have accumulated approximately 4 mg/kg mercury in his hair. By age 60, his hair mercury levels will have increased to about 7.5 mg/kg.
The effect of growth and physical condition on the level of heavy metals accumulated in the organs of common bream (Abramis brama L.) populating Lake Balaton was investigated on samples collected in October 1999 and May 2000 from two well-separable sites regarding their trophic state and pollution impact (western and eastern basins). The average metal concentrations in the organs of fish varied in the following ranges: Cd, 0.39-1.98; Cu, 1.73-57.3; Hg, 0.02-0.13; Pb, 0.39-3.15; and Zn, 12.7-159.3 microg/g dry weight. The highest Cd, Cu, Pb and Zn concentrations were detected in the gill and liver of fish, whereas the highest Hg concentrations were measured in the muscle. The maximum metal concentrations in the muscle of bream were on average below the maximum permissible levels for human consumption. Significant positive correlation was found among the heavy metal load of bream and their instantaneous growth rate; hardly any connection was observed related to the physical condition of samples. The relatively low metal concentrations of the ambient water and their poor correlation with the heavy metal load of bream, indicates that for the mature stages of this fish species the metal uptake from food is predominant, and thus the heavy metal load of fish reflect more the pollution state of the sediment and its biota, rather than that of the ambient water.
Japan experienced a very rapid industrialization and economic growth in the era of income doubling in 1960s and at the same time Japan experienced very severe damage from various types of environmental pollution. In this paper, historical development of population, GNP, energy consumption with classification of petroleum, coal and electric power, and CO2 emission are introduced as basic background data on Japanese development. The tragic experience of Minamata disease and Itai-itai disease caused by methyl mercury and cadmium, respectively, are introduced. In two tables, historical development of water pollution and air pollution are summarized. Regarding solid wastes management, the total mass balance in Japan and recent development in legislation framework for enhancement of recycling of wastes are introduced briefly.
Twentieth Century Atmospheric Metal Fluxes into Central Park Lake
- S N Chilrud
- Bopp
- Simpson
- Ross
- Shuster
- Da Chaky
- Walsh
- Choy
- Tolley
- Yarma
Chilrud SN, RF Bopp, HJ Simpson, JM Ross,
EL Shuster, DA Chaky, DC Walsh, CC
Choy, LR Tolley, A Yarma. 1999.
"Twentieth Century Atmospheric Metal
Fluxes into Central Park Lake, New York
City". Environmental Science and
Technology, 33(5): 657-662.
Heavy metal poisoning. Gale Encyclopedia of Alternative Medicine
- D Dupler
Dupler D. 2001. Heavy metal poisoning. Gale
Encyclopedia of Alternative Medicine.
Farmington Hills, MI: Gale Group.
Human Physiology and Mechanisms of Disease. WB Saunders Company: Philadelphia
- A C Guyton
Guyton AC.1982. Human Physiology and
Mechanisms of Disease. WB Saunders
Company: Philadelphia; 279-283.
Nutritional state modulates hormonemediated hepatic glycogenolysis in chinook salmon (Oncorhynchus tshawytscha)
- M Klee
- C Eilerson
- Sheridan Ma
Klee M, Eilerson C, Sheridan Ma. 1990.
Nutritional state modulates hormonemediated hepatic glycogenolysis in
chinook
salmon
(Oncorhynchus
tshawytscha). J. Exp. Zool., 254: 202-207.
Environmental Pollution, Neurotoxicity and Criminal Violence
- R Masters
Masters R. 1998. Environmental Pollution,
Neurotoxicity and Criminal Violence. In
J. Environmental Toxicology, Rose (ed).
Gordon and Breach: London.
Distribution of Cd, Zn and Cu in liver and gills of the eel Anguilla anguilla with special reference to metallothioneins
- F Noel-Lambot
- C Gierday
- A Disteche
Noel-Lambot F, Gierday C, Disteche A. 1978.
Distribution of Cd, Zn and Cu in liver and
gills of the eel Anguilla anguilla with
special reference to metallothioneins.
The science of the total environment, Alison. In Lead Blights the Future of Africa's Children, Motluk (ed)
- J Nriagu
Nriagu J, et al. 1996. The science of the total
environment, Alison. In Lead Blights the
Future of Africa's Children, Motluk (ed).
New Scientist, p. 6.
Safety and Health Topics: Toxic Metals. U.S. Dept. of Labor, Occupational Safety and Health (OSHA)
- Osha
Osha. 2004. Safety and Health Topics: Toxic
Metals.
U.S.
Dept.
of
Labor,
Occupational Safety and Health (OSHA)
[accessed July 3, 2006].
Pickering AD .1993. Endocrine-induced pathology in stressed salmonid fish
- Pearce Fred
Pearce Fred. 1997c. Mercurial storms rage in
the Arctic. New Scientist, 21 June, p.17.
Pickering AD.1993. Endocrine-induced
pathology in stressed salmonid fish. Fish.
Res., 17: 35-50.
Metal-gill surface interactions in Rainbow Trout (Onchorhynchus mykiss)
- Reid Sd
Reid Sd. 1990. Metal-gill surface interactions
in Rainbow Trout (Onchorhynchus
mykiss).
PhD
Thesis,
McMaster
University, Hamilton. Canada.
Metal toxicity in children
- J R Roberts
Roberts JR.1999. Metal toxicity in children. In
Training
Manual
on
Pediatric
Environmental Health. Emeryville CA:
Children's Environmental Health.
- B Vole
Vole B, sky. 1986. Biosorbent Materials,
Biotechnoi. Bioeng Symp., 16: 121-126.
CNN Environment. WHO: Geneva
- J Zarrella
Zarrella J. 1998. CNN Environment. WHO:
Geneva.
- Ieh
IEH. 1998. Institute of Environment and
Health at Leicester University. Report:
Recent UK Blood Lead Surveys. ISBN 1
899110 13 5.