Toxic Effects Of Heavy Metals Research Articles

Phospholipid scramblase 3: a latent mediator connecting mitochondria and heavy metal apoptosis.

Lead and mercury are the ubiquitous heavy metals triggering toxicity and initiating apoptosis in cells. Though the toxic effects of heavy metals on various organs are known, there is a paucity of information on the mechanisms that instigate the current study. A plausible role of phospholipid scramblase 3 (PLSCR3) in Pb2+ and Hg2+ induced apoptosis was investigated with human embryonic kidney (HEK 293) cells. After 12 h of exposure, ~30-40% of the cells were in the early stage of apoptosis with increased reactive oxygen species (ROS), decreased mitochondrial membrane potential, and increased intracellular calcium levels. Also, ~20% of the cardiolipin localized within the inner mitochondrial membrane was translocated to the outer mitochondrial membrane along with the mobilization of truncated Bid (t-Bid) to the mitochondria and cytochrome c from the mitochondria. The endogenous expression levels of PLSCR3, caspase 8, and caspase 3 were upregulated in Pb2+ and Hg2+ induced apoptosis. The activation and upregulation of PLSCR3 mediate CL translocation playing a potential role in initiating the heavy metal-induced apoptosis. Therefore, PLSCR3 could be the linker between mitochondria and heavy metal apoptosis.

Seasonal Variation and Association of Heavy Metals in the Vital Organs of Edible Fishes from the River Jhelum in Punjab, Pakistan.

The toxic effects of heavy metals are drastic, including accumulation. Fish species are important bio-indicators of heavy metal pollution in aquatic bodies. The current study aimed to assess the seasonal variation of heavy metals in the vital organs of mostly consumed fishes in River Jhelum, Pakistan. Samples of fish, including Wallago attu (Malhi), Rita rita (Khagga), and Mystus seenghala (Singhari), were collected from four different sites, i.e., Khushab, Muhammad Wala (M. Wala), 8.R.D and Rasool barrage during summer and winter seasons. Heavy metals such as iron (Fe), lead (Pb), chromium (Cr), cobalt (Co) and Cadmium (Cd) were estimated through acid digestion and spectrometric analysis. Results showed a significantly higher (P < 0.05) amount of these metals in the liver, followed by the kidneys of fish species. There were seasonal variations in the absorption of these metals as well. Cr (11.71) and Fe (58.66) were detected in higher amounts in Khagga which showed the greatest affinity for certain metals in some cases. In contrast, Singhari showed the greatest affinity to other metals in other cases. Comparative analysis revealed that there was a highly significant (P < 0.05) difference for the accumulation of almost all metals in both seasons and summer had the highest concentration of Cd, Pb, Co, Cr and Fe as compared to winter in all four sampling stations in the case of kidney and liver of all the three fishes. Elevated levels of heavy metals were detected in the summer due to increased temperature. Heavy metals found in the River Jhelum may demonstrate that metals can significantly affect the fish species.

Mitigating the negative effects of lead toxicity on Vigna mungo: The promising role of rhizobacteria

Growing Vigna mungo in soils contaminated with lead (Pb) is a major concern due to its negative impact on plant growth and development. When lead enters through food in the human body, it can be accumulated in bones, liver, and kidneys. In severe cases, lead poisoning can cause cancer, seizures, coma, and even death. To address this issue in plants, phosphate-solubilizing bacteria (PSB) have been identified as a potential solution to enhance plant growth and mitigate the harmful effects of heavy metal toxicity. However, the effectiveness of PSB can be improved by isolating and characterizing new strains over time, which will aid in developing sustainable management strategies for Pb-contaminated soils. Thus, the current study aimed to investigate the impact of Pb contamination on V. mungo growth and the potential use of newly isolated microbial strains to enhance V. mungo growth and immobilize Pb. Three levels of Pb contamination were used: control (no Pb toxicity), 125Pb (125 mg Pb/kg soil), and 250Pb (250 mg Pb/kg soil). Six different microbial strains, RP01, RP02, RP03, RP04, RP05, and RP06, were used to inoculate V. mungo seeds. The results of the experiment demonstrated that RP02 was the most effective strain in improving various growth parameters such as shoot length, root length, seedling length, fresh weight, dry weight, chlorophyll a, chlorophyll b, and total chlorophyll. While RP03 also showed significant improvement in these growth parameters, its effectiveness was not as high as RP02 in some respects. The efficacy of RP02 in alleviating Pb toxicity was further confirmed by a significant decrease in Pb concentration in the seedling, which was attributed to the production of siderophore. Therefore, it can be concluded that RP02 has the potential to improve V. mungo growth under Pb contamination. However, further field investigations are needed to confirm RP02 as the best strain for enhancing V. mungo production under Pb toxicity.

Risk assessment of combined exposure to lead, cadmium, and total mercury among the elderly in Shanghai, China

Lead (Pb), cadmium (Cd) and total mercury (THg) are toxic heavy metals (THMs) that are widely present in the environment and can cause substantial health problems. However, previous risk assessment studies have rarely focused on the elderly population and have usually targeted a single heavy metal, which might underestimate the long-term accumulative and synergistic effects of THMs in humans. Based on the food frequency questionnaire and inductively coupled plasma mass spectrometry, this study assessed external and internal exposures to Pb, Cd and THg in 1747 elderly people in Shanghai. Probabilistic risk assessment with the relative potential factor (RPF) model was used to assess the neurotoxicity and nephrotoxicity risks of combined THMs exposures. The mean external exposures of Pb, Cd and THg in Shanghai elderly were 46.8, 27.2 and 4.9 μg/day, respectively. Plant-based foods are the main source of Pb and THg exposure, while Cd is mainly from animal-based foods. The mean concentrations of Pb, Cd and THg were 23.3, 1.1 and 2.3 μg/L in the whole blood, and 6.2, 1.0 and 2.0 μg/L in the morning urine, respectively. Combined exposure to THMs leading to 10.0 % and 7.1 % of Shanghai elderly at risk of neurotoxicity and nephrotoxicity. The results of this study have important implications for understanding the profiles of Pb, Cd and THg exposure in the elderly living in Shanghai and provide data support for risk assessment and control of nephrotoxicity and neurotoxicity from combined THMs exposure in the elderly.

Effects of different concentrations of biochar amendments and Pb toxicity on rhizosphere soil characteristics and bacterial community of red clover (Trifolium pretense L.).

Amending soil with biochar can reduce the toxic effects of heavy metals (HM) on plants and the soil. However, the effects of different concentrations of biochar on the properties and microbial activities in lead (Pb)-contaminated soils are unclear. In this study, two Pb concentrations were set (low, 1000 mg/kg; high, 5000 mg/kg), and five corn straw biochar (CSB) concentrations (0, 2.5, 5, 10 and 15%) were used to determine the response of the growth and rhizosphere of red clover (Trifolium pretense L.) (in terms of soil properties and bacteria) to CSB and Pb application. The results showed that 5% CSB better alleviated the toxicity of Pb on the shoot length of red clover, the biomass increased by 74.55 and 197.76% respectively and reduced the enrichment factor (BCF) and transport factor (TF) of red clover. Pb toxicity reduced soil nutrients, catalase (CAT), acid phosphatase (ACP) and urease activity, while the addition of CSB increased soil pH, soil organic matter (SOM) content and soil enzyme activity. 16S rDNA amplicon sequencing analysis showed that Pb toxicity reduced the diversity of rhizosphere bacteria in red clover and reduced the relative abundance of plant growth-promoting rhizobacteria such as Gemmatimonas, Devosia and Bryobacter. Spearman correlation analysis showed that the addition of alkaline CSB restored the relative abundance of rhizobacteria positively correlated with pH, such as Chitinophaga, Sphingomonas, Devosia and Pseudomonas, and thus restored the rhizosphere soil environment. This study demonstrates that 5% CSB can better alleviate the toxicity of Pb to red clover and soil. We also provide a theoretical basis for the subsequent use of beneficial bacteria to regulate the repair efficiency of red clover.

A Feasibility Study on the Recall of Metallophilic Fungi from Fe(III)-Contaminated Soil and Evaluating Their Mycoremediation Capacity: Experimental and Theoretical Study

Mycoremediation is one of the most attractive, eco-friendly, and sustainable methods to mitigate the toxic effects of heavy metals. This study aimed to determine the mycoremediation capacity of metallophilic fungi isolated from heavy-metal-contaminated soil containing a high Fe(III) concentration (118.40 mg/kg). Four common fungal strains were isolated, including Curvularia lunata, Fusarium equiseti, Penicillium pinophilum, and Trichoderma harzianum. These fungal strains were exposed to gradually increasing concentrations of Fe(III) of 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000 mg/L. Sophisticated techniques and tests were employed to investigate the mycoremediation capability, including tolerance index (TI), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and adsorption isotherm. Furthermore, the impacts of initial concentration, pH, and temperature on the Fe(III) removal (%) and uptake capacity (mg/g) of the studied samples were investigated. The results were validated by statistical analysis using one-way ANOVA. It was found that the Fe(III) uptake with different ratios triggered alterations in the Fe(III) tolerance (TI) morphological (SEM), chemical (FTIR), and adsorption capacity properties. The highest Fe(III) tolerance for all studied fungal strains was achieved at 100 mg/L. Moreover, the optimum conditions of Fe(III) removal (%) for all studied fungal strains were within pH 7 and 28 °C, with similar performance at the initial Fe(III) concentration ranging from 50-200 mg/L. At the same time, the maximum Fe(III) uptake was achieved at pH 7, 20 °C, and 200 mg/L. Compared to other strains, the Fe(III) tolerance of T. harzianum was rise in the Fe(III) concentration. The Fe(III) uptake reaction was corroborated by best fitting with the Langmuir model, achieving optimum adsorption capacities of 61.34, 62.90, 63.30, and 72.46 mg/g for C.lunata, F. equiseti, P. pinophilum, T. harzianum, respectively. It can be deduced that the addressed fungi species can be applied in mycoremediation according to the utilized Fe(III) concentrations with more superiority for live T. harzianum.

Early immune response of neuronal cells (U87) to heavy metal Cd or Pb exposure.

Heavy metals such as lead (Pb) and cadmium (Cd) exist as particulate matter (PM) in the air and can cause biological damage to cells, animals, and humans. However, the mechanism underlying the toxic effects of heavy metals on nerve cells has not yet been completely identified. Glioma is the most common and fatal tumor in the central nervous system; the U87 human glioblastoma cell line is commonly used when researching brain cancer, including aggressive malignant gliomas. Therefore, in this study, cell viability, cytotoxicity, and interleukin-6 (IL-6) levels were analyzed to confirm the effect of Cd and Pb exposure on U87 cells. On confirming the absence of significant effects on cell viability at low concentrations of heavy metals, Cd and Pb exposure had no effect on lactic acid dehydrogenase (LDH) activity at the concentrations (1 μg/L, 30 μg/L, and 1 mg/L) used in this study, and there was a remarkable effect of Cd and Pb exposure on the inflammatory response of these cells. Our findings provide a basis for future research elucidating the effects of heavy metal exposure on cellular pathology. Systematic studies with higher heavy metal concentrations and precision are warranted to deepen our understanding of the relationship between heavy metal exposure and neuronal responses.

Contamination, ecological, and health risk assessment of heavy metals and organophosphorus pesticides in single, double, and ratoon cropping of rice: a case study in Mazandaran, North of Iran.

This study investigated the contamination and health risk assessment of heavy metals and organophosphorus pesticides in single, double, and ratoon cropping of rice in Mazandaran province, north of Iran. A total of 17 sampling locations in rice farms were selected and soil and rice samples were collected from farms in 5 counties of Mazandaran. Soil and rice samples were then transferred to the lab for further analysis. The concentration of pesticides and heavy metals was then analyzed using gas chromatography-mass spectrometry (GC-MS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Mercury was analyzed using a Leco mercury analyzer. Target hazard quotient (THQ), total target hazard quotient (TTHQ), carcinogenic risk (CR), and total carcinogenic risk (TCR) in children and adults were used. Potential ecological risk also was used to test the possible hazards of heavy metals to the environment. Heavy metals concentration in rice and soil samples in different farming steps revealed different levels. THQ showed no considerable risk in consuming contaminated rice to adults and children considered, while TTHQ revealed potential non-carcinogenic risks. Ni had the most carcinogenic risks to target human groups, and TCR showed carcinogenicity for carcinogenic heavy metals in all stations. Findings showed no ecological risks of metals to the environment. In conclusion, rice farmers in Mazandaran use the lands multiple times during the year to increase the performance, function, quality, and quantity of rice, but the possible toxic effects of heavy metals and pesticides on consumers and the environment should not be overlooked.

Mn/Al-layered Double Oxide-loaded Biochar Reduced the Toxic Effects of Heavy Metals on Ryegrass in Soil

The combined pollution of heavy metal Cu and Cd in soil induced by the e-waste dismantling process has become a severe problem. To deal with this issue, crab shell biochar (BC) and Mn/Al-layered double oxide-loaded crab shell biochar (LDO/BC) were prepared using coprecipitation and co-pyrolysis of discarded crab shells and manganese aluminum salt. The experimental results showed that not only were the soil pH, available phosphorus, available potassium, and soil enzymatic activity enhanced, but the contents of DTPA-Cu and DTPA-Cd in the soil were also reduced after remediation by BC and LDO/BC. Microbial community analysis indicated that BC-1% could promote the relative abundance of Gemmatimonadota and Acidobacteriota; meanwhile, LDO/BC-1% could promote the relative abundance of Proteobacteria, which could reduce the accumulation of Cd in plants. Ryegrass was planted for further investigating the toxic effect of heavy metals in soil after remediation. The results demonstrated that after remediating with BC-5% and LDO/BC-1%, ryegrass grew more vigorously and with a lower content of the heavy metals Cu and Cd in the plants than that of CK, and the germination rate increased by 29% and 60%, respectively. Further, LDO/BC-1% had a more excellent remediation performance than that of the other groups, and the Mn in LDO/BC could reduce the content of heavy metal Cd adsorbed by ryegrass in soil.

Effects of microplastic combined with Cr(III) on apoptosis and energy pathway of coral endosymbiont.

The combined effect of polyethylene (PE) microplastics and chromium (Cr(III)) on the scleractinian coral Acropora pruinosa (A. pruinosa) was investigated. The endpoints analysed in this study included the endosymbiont density, the chlorophyll a + c content, and the activity of enzymes involved in apoptosis (caspase-1, caspase-3), glycolysis (lactate dehydrogenase, LDH), the pentose phosphate pathway (glucose-6-phosphate dehydrogenase, G6PDH) and electron transfer coenzyme (nicotinamide adenine dinucleotide, NAD+/NADH). During the 7-day exposure to PE and Cr(III) stress, the endosymbiont density and chlorophyll content decreased gradually. The caspase-1 and caspase-3 activities increased in the high-concentration Cr(III) exposure group. Furthermore, the LDH and G6PDH activities decreased significantly, and the NAD+/NADH was decreased significantly. In summary, the results showed that PE and Cr(III) stress inhibited the endosymbiont energy metabolism enzymes and further led to endosymbiont apoptosis in coral. In addition, under exposure to the combination of stressors, when the concentration of Cr(III) remained at 1 × 10-2mg/L, the toxic effects of heavy metals on the endosymbiont were temporarily relieved with elevated PE concentrations. In contrast, when coral polyps were exposed to 5mg/L PE and increasing Cr(III) concentrations, their metabolic activities were seriously disturbed, which increased the burden of energy consumption. In the short term, the toxic effect of Cr(III) was more obvious than that of PE because Cr(III) exposure leads to endosymbiont apoptosis and irreversible damage. This is the first study to provide insights into the combined effect of microplastic and Cr(III) stress on the apoptosis and energy pathways of coral endosymbionts. This study suggested that microplastics combined with Cr(III) are an important factor affecting the apoptosis and energy metabolism of endosymbionts, accelerating the collapse of the balance between the coral host and symbiotic endosymbiont.

Evaluation of Heavy Metal Pollutants of Water on Fish Health and its Impact on Human Health

This review provides a summary of the toxic effects of heavy metals on fish. In the aquatic environment, these metals are important pollutants and are found in all ecosystems and are found in large quantities. Some heavy metals such as Cadmium, iron, copper, zinc and lead have the advantage of accumulating in tissues and poisoning fish. These minerals can effectively affect biological processes, fish reproduction, impair the immune system, and cause pathological changes. Therefore, heavy metals play an important role as a vital predictor of pollutants affecting the health and life of fish environments. These minerals cause organ damage even at low levels of exposure, so they have recently been classified as carcinogens. For all the above-mentioned reasons, this review has been written to contribute to the role of heavy metals in the environment, the toxic mechanism, the toxic effects on fish and the health of the human consumption of fish. Also, this article reviews the Histopathological change and biomarkers when exposed to heavy metal contamination.

Toxic Effects of Heavy Metals in Water

Several severe diseases have been influenced by the poisonous effects of heavy metals in water. Samples from afreshwater source and a water source running through an industrial town are taken to assess the rising quantities ofthese heavy metals. To determine if the concentration has increased over time, data from the same water source iscompared to data collected in 2009. The industrial workers were also surveyed via questionnaire to learn how thiswater is affecting them. Simple preventive measuresare included along with a variety of cutting-edge techniquesto eliminate hazardous metals from water.

A mini-review on innovative strategies for simultaneous microbial bioremediation of toxic heavy metals and dyes from wastewater.

Bioremediation of heavy metals and dyes is one of the emerging techniques globally as it is evident from the numerous publications made by various research groups. Biofilm-assisted bioremediation is one of the trending approaches as it facilitates negatively charged extracellular polymeric substances which makes the bacteria resistant to the toxic chemicals. Genetic engineering of microbes will make them unique in the bioremediation process. This mini-review concentrates on source and toxic effects of heavy metals and dyes on aqueous and living beings. Further, the genetic improvement strategies for effective bioremediation are described. However, the gap between practicability and real-time applicability needs to test with real-time wastewater in the industrial scale.

Assisted Phytostabilization of Mine-Tailings with Prosopis laevigata (Fabaceae) and Biochar.

Phytoremediation is a cost-effective technique to remediate heavy metal (HM) polluted sites. However, the toxic effects of HM can limit plant establishment and development, reducing phytoremediation effectiveness. Therefore, the addition of organic amendments to mine wastes, such as biochar, improves the establishment of plants and reduces the bioavailability of toxic HM and its subsequent absorption by plants. Prosopis laevigata can establish naturally in mine tailings and accumulate different HM; however, these individuals show morphological and genetic damage. In this study, the effect of biochar on HM bioaccumulation in roots and aerial tissues, HM translocation, morphological characters and plant growth were evaluated, after three and six months of exposure. Plants grown on mine tailings with biochar presented significantly higher values for most of the evaluated characters, in respect to plants that grew on mine tailing substrate. Biochar addition reduced the bioaccumulation and translocation of Cu, Pb, and Cd, while it favored the translocation of essential metals such as Fe and Mn. The addition of biochar from agro-industrial residues to mine tailings improves the establishment of plants with potential to phytoextract and phytostabilize metals from polluted soils. Using biochar and heavy metal accumulating plants constitutes an assisted phytostabilization strategy with great potential for HM polluted sites such as Cd and Pb.

Effect of heavy metal toxicity on Zooplankton population based on dyes and printing industries in Jodhpur (Rajasthan)

Effect of heavy metal toxicity on Zooplankton population based on dyes and printing industries in Jodhpur (Rajasthan)

Toxic effect of heavy metals on ovarian deformities, apoptotic changes, oxidative stress, and steroid hormones in rainbow trout

BackgroundAs is well known, the pollution in the aquatic environment in which fish grow has a direct impact on aquaculture practices. Pollution in aquatic systems because of multiple adverse effects on fish metabolic processes, especially the reproductive systems. AimThe goal of this study was to assess the severity of pollution impact in two different hatcheries, Verinag hatchery, Site 1 (S1) and Panzath hatchery, Site 2 (S2) in Anantnag region, using histopathological, ultrastructural, oxidative stress, genotoxic, and hormonal analysis in rainbow trout gonad (ovary).M&M: Fish were collected between May 2018 and April 2019 from two locations, Verinag hatchery (S1) and Panzath hatchery (S2), which were affected by heavy metals. ResultsThe histological and ultrastructural examination of rainbow trout ovaries from the Verinag hatchery (S1) revealed normal structure in growing oocytes in rainbow trout at various stages based on morphological features while the fish ovaries in the Panzath hatchery (S2) showed various deformities and irregularly shaped oocytes. The surfaces of some of these oocytes were wrinkled, rough, or distorted. Apoptotic studies revealed that the frequency of apoptotic cells collected from S2 water was significantly increased in ovarian cells (P < 0.05). The activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were found to be increased in fish collected from S1 but decreased in fish collected from S2. In S2 caught fish, malondialdehyde (MDA) levels were found to increase gradually, and the degree of heavy metal stress was positively correlated (p < 0.05). The comet assay was used to determine the induction of DNA damage in ovarian cells. The induction of DNA damage was found to be significantly higher (p < 0.05) in S2 fish specimens compared to fish from S1. On comparing the DNA damage of the rainbow trout from the two sampling sites, it was revealed that the fish is much more sensitive to aquatic contaminants. Regarding steroid hormones, higher levels of progesterone and estrogen were reported in the fish samples collected from S1 as compared to S2 captured fish. ConclusionIn conclusion, the comparative study of fish from two different sites viz. Verinag hatchery (S1) and Panzath hatchery (S2) revealed that S2 sampled fish suffered more heavy metal damage, including cellular deformities, apoptosis, oxidative damage, and altered steroid hormones.

The potential of terminalia catappa treat to inflammation on morphological erythrocyte of pangasius hypophthalmus poisoned with lead (pb)

This reseach concentrated on exploring the deformed erythrocytes morphology due to the effects of heavy metal toxicity and the size of erythrocytes when treated with almond leaves (Terminalia Catappa) on Pangasius Hypophthalmus. The fishes were fed with food mixed with almond leaves extract with concentrations of 0.3ml, 0.6ml, and 0.9ml in 7 days. After that, lead is contaminated with an amount of 1.0mg/l for all 3 treatments to evaluate the ability to treat inflammation in catfish contaminated with lead. The results when feeding fishes with almond leaves extract shown that the size of the area and circumference of erythrocytes increased, showing the ability to treat inflammation in Pangasius of almond leaves extract.

Indispensable role of melatonin, a scavenger of reactive oxygen species (ROS), in the protective effect of Akkermansia muciniphila in cadmium-induced intestinal mucosal damage.

The gastrointestinal tract is the main target of cadmium toxicity. However, whether Akkermansia muciniphila (A. muciniphila), which has been reported to be the next generation of promising probiotics, can alleviate cadmium-induced intestinal damage has not been investigated. In this study, we found that compared to the cadmium exposure group, mice gavaged with A. muciniphila showed less severe intestinal mucosal damage, with improved bodyweight, colon length, a decline in inflammation, and significantly increased glutathione and goblet cell numbers. Meanwhile, melatonin was interestingly found to be strikingly increased after A. muciniphila treatment. We then demonstrated that melatonin also could ameliorate the intestinal mucosal damage caused by cadmium through scavenging reactive oxygen species (ROS) and increasing the number of goblet cells. Furthermore, mice treated with inhibitors had a low level of melatonin and could not reproduce the beneficial effects of the A. muciniphila. Our results implied that the regulation of melatonin production by A. muciniphila is associated with an increase in enterochromaffin cells number, which determine melatonin secretion. This study indicated that the A. muciniphila-melatonin axis reduces cadmium-induced damage by increasing the goblet cells and scavenging the ROS, which may guide the prevention of the toxic effects of heavy metals.

Assessment of the Toxic Effects of Heavy Metals on Waterbirds and Their Prey Species in Freshwater Habitats.

Waterbirds may be a good indicator of harmful metal levels in aquatic environments. Waterbirds' organs and tissues were tested for the presence of pollutants, such as metals. However, very few reports describe the use of bird feathers and their prey in metal analysis. In the present research, seven metals were measured in the tissue, kidney, liver, and feathers of the Indian pond heron, the black-crowned night heron, and their prey species, including crabs, prawns, molluscs, and fishes from a freshwater lake. Metals were examined using an ECIL-4141-double beam atomic absorption spectrophotometer (DB-AAS). Metal concentrations differed considerably in the tissue, kidney, liver, and feathers of the Indian pond heron and black-crowned night heron (p &lt; 0.001). Indeed, this research discovered a good correlation between the metals of prey species and the tissues, kidneys, liver, and feathers of waterbirds that were tested. The regression model explained that the Cyprinus carpio influence the accumulation of metals about 98.2% in tissues, Macrobrachium rosenbergii and Cyprinus carpio around 86.3% in the kidney, the Labeo rohita almost 47.2% in the liver and Labeo rohita nearly 93.2% on the feathers of the Indian pond heron. On the other hand, the Mystus vittatus, Cyprinus carpio, Labeo rohita influence about 98.8% in tissue, the Claris batrachus and Tilapia mossambica around 93.3% in kidney, the Mystus vittatus, Cyprinus carpio, about 93.2% in liver and the freshwater crab (Travancoriana schirnerae), freshwater prawn (Macrobrachium rosenbergii) and a fish (Cyprinus carpio) nearly 93.2% in feathers in the black-crowned night heron. This research evaluated metals in the dead carcasses of waterbirds, a non-invasive biomonitoring technique for pollution. Overall, the investigation revealed that the lake is severely contaminated with metals. Therefore, the management and protection of aquatic habitats, particularly freshwater lakes, should be enhanced to rescue wild species that rely on aquatic ecosystems and to ensure that people have access to clean drinking water.

Chronic Exposure to Heavy Metals Declines Sperm Quality and Damages Tissue Architecture

This study aimed to assess the toxic effects of heavy metals in adult male rats after chronic exposure in early life stages. Juvenile male Wistar rats were kept in constant supply of drinking water having heavy metal salts such as Sodium Arsenite, Cadmium Chloride and Lead Acetate of dose 100 times higher than Maximum Contamination Limit (MCL; laid done by US EPA, 2009) for 3 months along with control rats with a supply of heavy metal free water. The result showed decreased sperm count and increase in abnormal sperm in all treated cases. Histopathology showed that testes and liver tissues of treated rats were severely damaged. Thus, this study showed that chronic exposure to heavy metals such as Arsenic, Cadmium and Lead in juvenile period may result in reduced reproductive capacity at later stage of life.