The Role of Selenium in Arsenic and Cadmium Toxicity: an Updated Review of Scientific Literature

Metal exposure in the Greenlandic ACCEPT cohort: follow-up and comparison with other Arctic populations

Humans are exposed to metals through diet and lifestyle e.g. smoking. Some metals are essential for physiologically body functions, while others are non-essential and can be toxic to humans. This study follows up on metal concentrations in the Greenlandic ACCEPT birth-cohort (mothers and fathers) and compares with other Arctic populations. The data from 2019 to 2020 include blood metal concentrations, lifestyle and food frequency questionnaires from 101 mothers and 76 fathers, 24-55 years, living in Nuuk, Sisimiut, and Ilulissat. A high percentage (25-45%) exceeded international guidance values for Hg. For the mothers, the metal concentrations changed significantly from inclusion at pregnancy to this follow-up 3-5 years after birth; some increased and others decreased. Most metals differed significantly between mothers and fathers, while few also differed between residential towns. Several metals correlated significantly with marine food intake and socio-economic factors, but the direction of the correlations varied. Traditional marine food intake was associated positively with Se, As and Hg. To the best of our knowledge, this study provides the most recent data on metal exposure of both men and women in Greenland, elucidating metal exposure sources among Arctic populations, and documents the need for continuing biomonitoring to follow the exceeding of guidance values for Hg. [Figure: see text].

Therapeutic Efficacy of Selenium Pre-treatment in Mitigating Cadmium-Induced Cardiotoxicity in Zebrafish (Danio rerio)

Cardiovascular diseases are a rampant public health threat. Environmental contaminants, such as Cadmium (Cd), a toxic metal, are risk factors for cardiovascular diseases. Given that human exposure to Cd is increasing, there is a need for therapies to ameliorate Cd toxicity. Selenium (Se), an essential trace element, has been proposed to rescue the effects of Cd toxicity, with mixed effects. Se's narrow therapeutic window necessitates precise dosing to avoid toxicity. Here, we assessed the effects of various waterborne Cd and Se concentrations and sequences on cardiac function using zebrafish (Danio rerio). We showed that Cd induced pericardial edemas and modified heart rates in zebrafish larvae in a concentration-dependent manner. To identify the therapeutic range of Se for Cd-induced cardiotoxicity, zebrafish embryos were treated with 0, 10, 50, 100, 150, or 200 μg/L Se for 1-4 days prior to exposure to 2.5 and 5 μg/L Cd. We found that a 50 µg/L Se pre-treatment before 2.5 μg/L Cd, but not 5 μg/L Cd, reduced the prevalence of pericardial edemas and ameliorated Cd-induced bradycardia in zebrafish. Zebrafish exposed to 10 and 50 μg/L of Se for up to 4 days showed typical heart morphology, whereas other Se-exposed and control fish presented pericardial edemas. Longer Se pre-treatment durations led to fewer incidences of pericardial edemas. Overall, this study highlights the importance of optimizing Se concentrations and pre-treatment periods to harness its protective effects against Cd-induced cardiotoxicity. These findings provide insights into potential therapeutic strategies for reducing Cd-related cardiovascular damage in humans.

Selenate simultaneously alleviated cadmium and arsenic accumulation in rice (Oryza sativa L.) via regulating transport genes

Cadmium (Cd) and arsenic (As) have contrasting biogeochemical behaviors in paddy soil, which posed an obstacle for reducing their accumulation in rice (Oryza sativa L.) simultaneously. In this study, selenate exhibited a more effective ability than selenite on simultaneous alleviation of Cd and As accumulation in rice under Cd-As co-exposure, and the mechanisms need to be further investigated. The results showed that selenate significantly decreased the root Cd and As contents by 59%-83% and 43%-72% compared to Cd-As compound exposure, respectively. Correspondingly, it significantly down-regulated the expression of uptake-related genes OsNramp5 (87.1%) and OsLsi1 (95.5%) in rice roots. Decreases in Cd (64.5%) and As (16.2%) contents in shoots were also found after selenate addition. Moreover, selenate may promoted the reduction of As(V) to As(Ⅲ) and As(III) efflux to the external medium, resulting in decreased As accumulation and As(Ⅲ) proportion in rice shoots and roots. In addition, selenate could promote the binding of Cd (by 14%-24%) and As (by 9%-15%) in the cell wall, and significantly reduced the oxidative stress by elevating levels of antioxidant enzymes (by 10%-105%) and thiol compounds (by 6%-210%). Additionally, selenate significantly down-regulated the expression of OsNramp1 (49.3%) and OsLsi2 (82.1%) associated with Cd and As transport in rice. These findings suggest selenate has the potential to be an effective material for the simultaneous reduction of Cd and As accumulation in rice under Cd-As co-contamination.

Sodium Selenite Ameliorates Silver Nanoparticles Induced Vascular Endothelial Cytotoxic Injury by Antioxidative Properties and Suppressing Inflammation Through Activating the Nrf2 Signaling Pathway

Silver nanoparticles (AgNP) are the dominant nanomaterials in commercial products and the medical field, but the widespread occurrence of AgNP has become a global threat to human health. Growing studies indicate that AgNP exposure can induce vascular endothelial toxicity by excessive oxidative stress and inflammation, which is closely related to cardiovascular disease (CVD), but the potential intrinsic mechanism remains poorly elucidated. Thus, it has been crucial to control the toxicological effects of AgNP in order to improve their safety and increase the outcome of their applications.Multiple researches have demonstrated that sodium selenite (Se) possesses the capability to counteract the toxicity of AgNP, but the functional role of Se in AgNP-induced CVD is largely unexplored. The aim of this study was to explore the potential protective effect of Se on AgNP-induced vascular endothelial lesion and elucidate the underlying mechanisms. An in vivo model of toxicity in animals was established by the instillation of 200 µL of AgNP into the trachea of rats both with (0.2 mg/kg/day) and without Se treated. In vitro experiments, human umbilical vein endothelial cells (HUVECs) were incubated with AgNP (0.3 µg/mL ) and Se for a duration of 24 h. Utilizing transmission electron microscopy, we observed that the internalization of AgNP-induced endothelial cells was desquamated from the internal elastic lamina, the endoplasmic reticulum was dilated, and the medullary vesicle formed. Se treatment reduced the levels of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), inhibited the release of pro-inflammatory cytokines (specifically tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6), improved endothelial cell permeability, integrity, and dysfunction, and prevented damage to the aortic endothelium caused by AgNP. Importantly, we found that Se showed the capacity against AgNP with biological functions in guiding the intracellular reactive oxygen species (ROS) scavenging and meanwhile exhibiting anti-inflammation effects. Se supplementation decreased the intracellular ROS release and suppressed NOD-like receptor protein 3 (NLRP3) and nuclear factor kappa-B (NF-κB) mediated inflammation within AgNP-intoxicated rats and HUVECs. The anti-oxidant stress and anti-inflammatory effects of Se were at least partly dependent on nuclear factor erythroid 2-related factor 2 (Nrf2). Overall, our results indicated that the protectiveness of Se against AgNP-induced vascular endothelial toxicity injury was at least attributed to the inhibition of oxidative ROS and pro-inflammatory NF-κB/NLRP3 inflammasome by activating the Nrf2 and antioxidant enzyme (HO-1) signal pathway.

Selenium Improves Arsenic-Induced Male Reproductive Dysfunction by Regulating H3K14ac Level

Arsenic exposure has been known to be associated with male reproduction injury. Exploring the antidote of arsenic and ascertaining proper dose of antidote are important for detoxifying the male reproductive toxicity of arsenic. Selenium, which is essential for the male reproduction and spermatogenesis, can alleviate the toxicity of many environmental toxins, such as metals, and fluoride (F). Selenium relieves arsenic-induced reductions in spermatogenesis index and testicular function marker enzymes via promoting the antioxidative ability of rats. Our previous study has found that arsenic can induce male reproductive toxicity by affecting the level of H3K14ac in the testis, so we further investigate whether selenium can antagonize arsenic-induced male reproductive toxicity through the H3K14ac pathway and ascertain the appropriate dose of selenium. The results show that selenium intervention reduces the accumulation of arsenic in rat testis probably attributing to promote the excretion of arsenic from rat, then improves the testis injury induced by arsenic. Selenium intervention enhances sperm quality, testosterone level, and expression of steroidogenic genes by regulating H3K14ac level and expression of its associated enzymes (KAT2A, BAZ2A, and HDAC6), and thus alleviates the male reproductive toxicity of arsenic, and the proper dose of Se for mitigating arsenic male reproductive toxicity is 1 mg/kg.

The Immunomodulatory Effects of Selenium: A Journey from the Environment to the Human Immune System

Selenium (Se) is an essential nutrient that has gained attention for its impact on the human immune system. The purpose of this review is to explore Se's immunomodulatory properties and to make up-to-date information available so novel therapeutic applications may emerge. People acquire Se through dietary ingestion, supplementation, or nanoparticle applications. These forms of Se can beneficially modulate the immune system by enhancing antioxidant activity, optimizing the innate immune response, improving the adaptive immune response, and promoting healthy gut microbiota. Because of these many actions, Se supplementation can help prevent and treat pathogenic diseases, autoimmune diseases, and cancers. This review will discuss Se as a key micronutrient with versatile applications that supports disease management due to its beneficial immunomodulatory effects. Further research is warranted to determine safe dosing guidelines to avoid toxicity and refine the application of Se in medical treatments.

Toxic Effects of Cadmium Exposure on Hematological and Plasma Biochemical Parameters in Fish: A Review

Cadmium (Cd) is a non-essential trace element that poses significant toxic effects on fish. This review focuses on hematological and plasma biochemical parameters as key indicators of fish health under Cd exposure. Hematological parameters, such as red blood cell (RBC) count, hemoglobin (Hb) concentration, and hematocrit (Ht), were selected for their critical role in oxygen transport and their sensitivity to Cd-induced disruptions, which often result in anemia and impaired oxygen delivery to tissues. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) provide further insights into erythropoiesis and hemoglobin synthesis, both of which are essential for assessing Cd toxicity. Plasma biochemical parameters, including calcium, magnesium, glucose, cholesterol, total protein, and liver enzymes such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP), are crucial for understanding ionic balance, metabolic regulation, and organ function, especially in fish exposed to Cd. These biomarkers offer a comprehensive view of the physiological stress and organ damage caused by Cd toxicity. This review synthesizes literature findings on the toxic effects of Cd on these parameters. It also discusses potential mitigation strategies, including dietary supplementation with antioxidants and trace elements, to counteract the harmful effects of Cd exposure.

Disrupted Prenatal Metabolism May Explain the Etiology of Suboptimal Neurodevelopment: A Focus on Phthalates and Micronutrients and their Relationship to Autism Spectrum Disorder

Pregnancy is a time of high metabolic coordination, as maternal metabolism adapts to support the growing fetus. Many of these changes are coordinated by the placenta, a critical fetal endocrine organ and the site of maternal-fetal crosstalk. Dysregulation in maternal and placental metabolism during pregnancy has been linked to adverse outcomes, including altered neurodevelopment. Autism spectrum disorder (ASD) is a neurodevelopmental disorder linked to metabolic alterations in both children and their mothers. Prenatal environmental exposures have been linked to risk of ASD through dysregulated maternal, placental, and fetal metabolism. In this review, we focus on recent studies investigating the associations between prenatal metabolism in the maternal-placental-fetal unit and the impact of prenatal environmental exposures to phthalates and micronutrients on ASD risk. By identifying the mechanisms through which phthalates and other ubiquitous endocrine disrupting chemicals influence development, and how nutritional interventions can impact those mechanisms, we can identify promising ways to prevent suboptimal neurodevelopment.

Transcriptional and biochemical changes in mouse liver following exposure to a metal/drug cocktail. Attenuating effect of a selenium-enriched diet

Real-life pollution usually involves simultaneous co-exposure to different chemicals. Metals and drugs are frequently and abundantly released into the environment, where they interact and bioaccumulate. Few studies analyze potential interactions between metals and pharmaceuticals in these mixtures, although their joint effects cannot be inferred from their individual properties. We have previously demonstrated that the mixture (PC) of the metals Cd and Hg, the metalloid As and the pharmaceuticals diclofenac (DCF) and flumequine (FLQ) impairs hepatic proteostasis. To gain a deeper vision of how PC affects mouse liver homeostasis, we evaluated here the effects of PC exposure upon some biochemical and morphometric parameters, and on the transcriptional profiles of selected group of genes. We found that exposure to PC caused oxidative damage that exceeded the antioxidant capacity of cells. The excessive oxidative stress response resulted in an overabundance of reducing equivalents, which hindered the metabolism and transport of metabolites, including cholesterol and bile acids, between organs. These processes have been linked to metabolic and inflammatory disorders, cancer, and neurodegenerative diseases. Therefore, our findings suggest that unintended exposure to mixtures of environmental pollutants may underlie the etiology of many human diseases. Fortunately, we also found that a diet enriched with selenium mitigated the harmful effects of this combination of toxicants.

Selenium restored mitophagic flux to alleviate cadmium-induced hepatotoxicity by inhibiting excessive GPER1-mediated mitophagy activation

Cadmium (Cd) is a common environmental pollutant, while selenium (Se) can ameliorate heavy metal toxicity. Consequently, this study aimed to investigate the protective effects of Se against Cd-induced hepatocyte injury and its underlying mechanisms. To achieve this, we utilized the Dongdagou-Xinglong cohort, BRL3A cell models, and a rat model exposed to Cd and/or Se. The results showed that Se counteracted liver function injury and the decrease in GPER1 levels caused by environmental Cd exposure, and various methods confirmed that Se could protect against Cd-induced hepatotoxicity both in vivo and in vitro. Mechanistically, Cd caused excessive mitophagy activation, evidenced by the colocalization of LC3B, PINK1, Parkin, P62, and TOMM20. Transfection of BRL3A cells with mt-keima adenovirus indicated that Cd inhibited autophagosome-lysosome fusion, thereby impeding mitophagic flux. Importantly, G1, a specific agonist of GPER1, mitigated Cd-induced mitophagy overactivation and hepatocyte toxicity, whereas G15 exacerbates these effects. Notably, Se supplementation attenuated Cd-induced GPER1 protein reduction and excessive mitophagy activation while facilitating autophagosome-lysosome fusion, thereby restoring mitophagic flux. In conclusion, this study proposed a novel mechanism whereby Se alleviated GPER1-mediated mitophagy and promoted autophagosome-lysosome fusion, thus restoring Cd-induced mitophagic flux damage, and preventing hepatocyte injury.

The preventive and carcinogenic effect of metals on cancer: a systematic review

BACKGROUND

Many studies have investigated the role of metals in various types of malignancies. Considering the wide range of studies conducted in this field and the achievement of different results, the presented systematic review was performed to obtain the results of investigations on the prevention and occurrence of various types of cancer associated with metal exposures.

METHODS

In this review, research was conducted in the three databases: Scopus, PubMed, and Web of Science without historical restrictions until May 31, 2024. Animal studies, books, review articles, conference papers, and letters to the editors were omitted. The special checklist of Joanna Briggs Institute (JBI) was used for the quality assessment of the articles. Finally, the findings were classified according to the effect of the metal as preventive or carcinogenic.

RESULTS

The total number of retrieved articles was 4695, and 71 eligible results were used for further investigation. In most studies, the concentration of toxic metals such as lead (Pb), chromium (Cr (VI)), arsenic (As), cadmium (Cd), and nickel (Ni) in the biological and clinical samples of cancer patients was higher than that of healthy people. In addition, the presence of essential elements, such as selenium (Se), zinc (Zn), iron (Fe), and manganese (Mn) in tolerable low concentrations was revealed to have anti-cancer properties, while exposure to high concentrations has detrimental health effects.

CONCLUSIONS

Metals have carcinogenic effects at high levels of exposure. Taking preventive measures, implementing timely screening, and reducing the emission of metal-associated pollutants can play an effective role in reducing cancer rates around the world.

A review of amendments for simultaneously reducing Cd and As availability in paddy soils and rice grain based on meta-analysis

Arsenic (As) and cadmium (Cd) accumulation in rice grains is a global food safety issue, and various methods and materials have been used to remove or reduce As and Cd in agricultural soils and rice grains. Despite the availability of synthesized materials capable of simultaneous As and Cd reduction from soil and rice grains, the contributions, efficiency, and main ingredients of the materials for As and Cd immobilization remain unclear. The present study first summarized the biogeochemistry of As and Cd in paddy soils and their transfer in the soil-food-human continuum. We also reviewed a series of reported inorganic and organic materials for simultaneous immobilization of As and Cd in paddy soils, and their reduction efficiency of As and Cd bioavailability were listed and compared. Based on the abovementioned materials, the study conducted a meta-analysis of 38 articles with 2565 observations to quantify the impacts of materials on simultaneous As and Cd reduction from soil and rice grains. Meta-analysis results showed that combining organic and inorganic amendments corresponded to effect sizes of -62.3% and -67.8% on As and Cd accumulation in rice grains, while the effect sizes on As and Cd reduction in paddy soils were -44.2% and -46.2%, respectively. Application of Fe based materials significantly (P < 0.05) reduced As (-54.2%) and Cd (-74.9%), accounting for the highest immobilization efficiency of As and Cd in rice grain among all the reviewed materials, outweighing S, Mn, P, Si, and Ca based materials. Moreover, precipitation, surface complexation, ion exchange, and electrostatic attraction mechanisms were involved in the co-immobilization tactics. The present study underlines the application of combined organic and inorganic amendments in simultaneous As and Cd immobilization. It also highlighted that employing Fe-incorporated biochar material may be a potential strategy for co-mitigating As and Cd pollution in paddy soils and accumulation in rice grains.

The Effects of Seleno-Methionine in Cadmium-Challenged Human Primary Chondrocytes

Cadmium (Cd) is a potentially toxic element able to interfere with cellular functions and lead to disease or even death. Cd accumulation has been demonstrated in cartilage, where it can induce damage in joints. The aim of this study was to evaluate the effect of CdCl2 on primary cultures of human chondrocytes and the possible protective effect of seleno-methionine (Se-Met). Human primary articular chondrocytes were cultured and treated as follows: control groups, cells challenged with 7.5 μM and 10 μM CdCl2 alone, and cells pretreated with 10 and 20 μM Se-Met and then challenged with 7.5 μM and 10 μM CdCl2. Twenty-four hours after incubation, cell viability, histological evaluation with hematoxylin-eosin stain, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were performed. Furthermore, reverse transcription-PCR was carried out to evaluate mRNA levels of BAX, BAK1, CASP-3, and CASP-9. After CdCl2 challenge at both doses, a reduced cell viability and an overexpression of BAX, BAK1, CASP-3, and CASP-9 genes, as well as a high number of TUNEL-positive cells, were demonstrated, all parameters becoming higher as the dose of CdCl2 was increased. The pretreatment with Se-Met lowered the expression of all considered genes, improved cell viability and morphological changes, and reduced the number of TUNEL-positive cells. It was concluded that Se-Met plays a protective role against CdCl2-induced structural and functional changes in chondrocytes in vitro, as it improved cell viability and showed a positive role in the context of the apoptotic pathways. It is therefore suggested that a translational, multifaceted approach, with plant-based diets, bioactive functional foods, nutraceuticals, micronutrients, and drugs, is possibly advisable in situations of environmental pollution caused by potentially toxic elements.

Metal mixture exposures and serum lipid levels in childhood: the Rhea mother-child cohort in Greece

BACKGROUND

Growing evidence suggests that cardiovascular disease develops over the lifetime, often beginning in childhood. Metal exposures have been associated with cardiovascular disease and important risk factors, including dyslipidemia, but prior studies have largely focused on adult populations and single metal exposures.

OBJECTIVE

To investigate the individual and joint impacts of multiple metal exposures on lipid levels during childhood.

METHODS

This cross-sectional study included 291 4-year-old children from the Rhea Cohort Study in Heraklion, Greece. Seven metals (manganese, cobalt, selenium, molybdenum, cadmium, mercury, and lead) were measured in whole blood using inductively coupled plasma mass spectrometry. Serum lipid levels included total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol. To determine the joint and individual impacts of child metal exposures (log2-transformed) on lipid levels, Bayesian kernel machine regression (BKMR) was employed as the primary multi-pollutant approach. Potential effect modification by child sex and childhood environmental tobacco smoke exposure was also evaluated.

RESULTS

BKMR identified a positive association between the metal mixture and both total and LDL cholesterol. Of the seven metals examined, selenium (median 90.6 [IQR = 83.6, 96.5] µg/L) was assigned the highest posterior inclusion probability for both total and LDL cholesterol. A difference in LDL cholesterol of 8.22 mg/dL (95% CI = 1.85, 14.59) was observed when blood selenium was set to its 75th versus 25th percentile, holding all other metals at their median values. In stratified analyses, the positive association between selenium and LDL cholesterol was only observed among boys or among children exposed to environmental tobacco smoke during childhood.

IMPACT STATEMENT

Growing evidence indicates that cardiovascular events in adulthood are the consequence of the lifelong atherosclerotic process that begins in childhood. Therefore, public health interventions targeting childhood cardiovascular risk factors may have a particularly profound impact on reducing the burden of cardiovascular disease. Although growing evidence supports that both essential and nonessential metals contribute to cardiovascular disease and risk factors, such as dyslipidemia, prior studies have mainly focused on single metal exposures in adult populations. To address this research gap, the current study investigated the joint impacts of multiple metal exposures on lipid concentrations in early childhood.

Inhibitory effects of glutathione peroxidase on microbial spoilage of crayfish (Procambarus clarkii) during refrigerated storage

The variety of enzyme-based biological preservatives is limited. This study evaluated the effects of glutathione peroxidase (GSH-Px) on the quality of crayfish during refrigerated storage by measuring the pH, total volatile basic nitrogen, trimethylamine, and microbial contamination in crayfish muscle simulation system. The results revealed that 0.3% GSH-Px (CK3) not only suppressed the degradation of nitrogenous substances but also decreased the contamination levels of total viable, Enterobacteriaceae, and Pseudomonas counts (P < 0.05). Furthermore, the populations of Lactococcus, Aeromonas, and Massilia differed in the CK3 group compared to the other groups (P < 0.05) at the end of the storage (day 15). Moreover, the principal coordinate analysis showed that the colony composition of CK3 stored for 15 days was similar to that of the control group stored for 10 days. Therefore, GSH-Px exhibits antibacterial activity against Gram-negative bacteria and has good application potential in freshwater aquatic product preservation.

Assessment of the Impact of Trace Essential Metals on Cancer Development

This study examines the impact of zinc, copper, cobalt, iron, and manganese on cancer development, considering their dual roles as potential promoters or inhibitors within tumorigenesis. A comprehensive analysis of existing literature and experimental data is conducted to elucidate the intricate relationship between these trace elements and cancer progression. The findings highlight the multifaceted effects of zinc, copper, cobalt, iron, and manganese on various aspects of cancer development, including cell proliferation, angiogenesis, and metastasis. Understanding the nuanced interactions between these trace elements and cancer could offer crucial insights into tumorigenesis mechanisms and facilitate the identification of novel biomarkers and therapeutic targets for cancer prevention and treatment strategies. This research underscores the importance of considering the roles of essential trace elements in cancer biology and may ultimately contribute to advancements in precision medicine approaches for combating cancer.

The physiological levels of epigallocatechin gallate (EGCG) enhance the Cd-induced oxidative stress and apoptosis in CHO-K1 cells

Currently, the increasing pollution of the environment by heavy metals is observed, caused both by natural factors and those related to human activity. They pose a significant threat to human health and life. It is therefore important to find an effective way of protecting organisms from their adverse effects. One potential product showing a protective effect is green tea. It has been shown that EGCG, which is found in large amounts in green tea, has strong antioxidant properties and can therefore protect cells from the adverse effects of heavy metals. Therefore, the aim of the study was to investigate the effect of EGCG on cells exposed to Cd. In the study, CHO-K1 cells (Chinese hamster ovary cell line) were treated for 24 h with Cd (5 and 10 µM) and EGCG (0.5 and 1 µM) together or separately. Cell viability, ATP content, total ROS activity, mitochondrial membrane potential and apoptosis potential were determined. The results showed that, in tested concentrations, EGCG enhanced the negative effect of Cd. Further analyses are needed to determine the exact mechanism of action of EGCG due to the small number of publications on the subject and the differences in the results obtained in the research.

Arsenic and cadmium availability and its removal in paddy farming areas

Arsenic (As) and cadmium (Cd) accumulation in rice grain is a global concern threatening food security and safety to the growing population. As and Cd are toxic non-essential elements poisonous to animal and human at higher levels. Its accumulation in agro-ecosystems pose a public health risk to consumers of agro-ecosystem products. Due to their hazards, As and Cd sources should be cleared, avoiding entering plants and the human body. As and Cd removal in soils and grains in agro-ecosystems has been conducted by various materials (natural and synthesized), however, there are little documentation on their contribution on As and Cd removal or reduction in rice grains. This identified knowledge gap necessitate a systematically review to understand efficiency and mechanisms of As and Cd availability reduction and removal in paddy farming areas through utilization of various synthetic and modified materials. To achieve this, published peer reviewed articles between 2010 and 2024 were collected from various database i.e., Science Direct, Web of Science, Google Scholar, and Research Gate and analyzed its content in respect to As and Cd reduction and removal. Furthermore, collected data were re-analyzed to determine standardized mean differences (SMD) with 95% confidence intervals (CI). Based on 96 studies with 228 observations involving Fe, Ca, Si, and Se-based materials were identified, it was found that application of Fe, Ca, Si, and Se-based materials potentially reduced As and Cd in rice grains among various study sites and across studies. Among the studied materials, Fe-based materials observed to be more efficient compared to other utilized materials. However, there little or no information on performance of materials when used in combination and how they can improve crop productivity and soil health, thus requiring further studies. Thus, this study confirm Fe, Ca, Si, and Se modified materials have significant potential to reduce As and Cd availability in paddy farming areas and rice grains, thus necessary effort must be made to ensure materials access and availability for farmers utilization in paddy fields to reduce As and Cd accumulation.

Turning sublimed sulfur and bFGF into a nanocomposite to accelerate wound healing via co-activate FGFR and Hippo signaling pathway

Clinical treatment of diabetic refractory ulcers is impeded by chronic inflammation and cell dysfunction associated with wound healing. The significant clinical application of bFGF in wound healing is limited by its instability in vivo. Sulfur has been applied for the treatment of skin diseases in the clinic for antibiosis. We previously found that sulfur incorporation improves the ability of selenium nanoparticles to accelerate wound healing, yet the toxicity of selenium still poses a risk for its clinical application. To obtain materials with high pro-regeneration activity and low toxicity, we explored the mechanism by which selenium-sulfur nanoparticles aid in wound healing via RNA-Seq and designed a nanoparticle called Nano-S@bFGF, which was constructed from sulfur and bFGF. As expected, Nano-S@bFGF not only regenerated zebrafish tail fins and promoted skin wound healing but also promoted skin repair in diabetic mice with a profitable safety profile. Mechanistically, Nano-S@bFGF successfully coactivated the FGFR and Hippo signalling pathways to regulate wound healing. Briefly, the Nano-S@bFGF reported here provides an efficient and feasible method for the synthesis of bioactive nanosulfur and bFGF. In the long term, our results reinvigorated efforts to discover more peculiar unique biofunctions of sulfur and bFGF in a great variety of human diseases.

Association between Sperm Mitochondrial DNA Copy Number and Concentrations of Urinary Cadmium and Selenium

Elevated sperm mitochondrial DNA copy number (mtDNAcn) is associated with damage to sperm and poorer measures of semen quality. Exposure to cadmium (Cd) can increase oxidative stress and damage sperm mitochondria. The adverse effects of Cd can potentially be reduced by sufficient selenium (Se). The objective of this study was to examine the associations between sperm mtDNAcn and urinary concentrations of Cd and Se, as well as the Cd/Se molar ratio. Participants were recruited from patients who sought infertility treatment at two hospitals in Japan. Urine and semen specimens and self-administered questionnaires were collected on the day of recruitment. Sperm mtDNAcn was measured in extracted sperm DNA by multiplex real-time qPCR. Urinary Cd and Se concentrations were measured using inductively coupled plasma mass spectrometry, and their molar weights were calculated to obtain the Cd/Se molar ratio. Linear regression was used to estimate associations after adjusting for age, body mass index, smoking, drinking, exercise, varicocele, and hospital of recruitment. Sperm mtDNAcn showed statistically insignificant associations with creatinine-adjusted concentrations of urinary Cd (β = 0.13, 95% CI -0.18, 0.44) and Se (β = -0.09, 95% CI -0.54, 0.35), and Cd/Se molar ratio (β = 0.12, 95% CI -0.13, 0.37). The current study found no evidence of an association between mtDNAcn and urinary concentrations of Cd or Se, or the Cd/Se molar ratio.

Variability of the Ionome of Wild Boar (Sus scrofa) and Red Deer (Cervus elaphus) in a Dutch National Park, with Implications for Biomonitoring

The ionome-an important expression of the physiological state of organisms-is poorly known for mammals. The focus on particular tissues-such as liver, kidney, and bones-in biomonitoring of environmental pollution and potential deficiencies is based on widely held assumptions rather than solid knowledge of full mammalian ionomes. We examined the full ionome of Red deer (Cervus elaphus) and Wild boar (Sus scrofa), two commonly used mammals for biomonitoring, in a Dutch protected nature reserve (Veluwezoom). We used four individuals per species. We dissected 13 tissues and organs from each individuals (eight in total) of each species and measured 22 elemental concentrations in each. We assessed, for each element, how concentrations varied across tissues within and between individuals. Based on existing literature, we put our findings in the context of their function in the mammalian body. We found that the ionome was highly variable between as well as within the two species. For most elements, tissues containing the highest and lowest concentration differed between individuals. No single tissue accurately represented the accumulation of toxic elements or potential deficiencies in the bodies. Our assessment of the element's biological roles revealed a serious lack of reference values. Our findings imply that analyses of commonly used tissues in biomonitoring do not necessarily capture bioaccumulation of toxins or potential deficiencies. We recommend establishing a centralized database of mammalian ionomes to derive reference values in future. To our knowledge, our study is one of the most complete assessments of mammalian ionomes to date.

Nano-Selenium Alleviates Cd-Induced Chronic Colitis through Intestinal Flora

BACKGROUND

Cadmium (Cd) is an environmental contaminant that poses risks to human and animal health. Selenium (Se), a beneficial element, alleviates the detrimental consequences of colitis and Cd toxicity. Se is found in food products as both inorganic Se (sodium selenite) and organic Se (typically Se-enriched yeast). Nano-selenium (nano-Se; a novel form of Se produced through the bioreduction of Se species) has recently garnered considerable interest, although its effects against Cd-induced enterotoxicity are poorly understood. The aim of this study was to investigate the impact of nano-selenium on mitigating cadmium toxicity and safeguarding the integrity of the intestinal barrier.

METHODS

For a total of two cycles, we subjected 6-week-old C57 mice to chronic colitis by exposing them to Cd and nano-selenium for two weeks, followed by DSS water for one week.

RESULTS

The application of nano-selenium mitigated the intensity of colitis and alleviated inflammation in the colon. Nano-selenium enhanced the diversity of the intestinal flora, elevated the concentration of short-chain fatty acids (SCFAs) in feces, and improved the integrity of the intestinal barrier.

CONCLUSIONS

In summary, nano-Se may reduce intestinal inflammation by regulating the growth of intestinal microorganisms and protecting the intestinal barrier.

Selenosalicylate; a little-studied heavy-element analogue of the versatile thiosalicylate ligand

Selenosalicylic acid (ortho-HSeC6H4CO2H), the heavy element congener of the widely studied thiosalicylic acid, was prepared by reaction of 2-carboxybenzenediazonium chloride (HO2CC6H4N2+Cl-) with Na2Se2, followed by reduction of the resulting diselenide (SeC6H4CO2H)2 with zinc and acetic acid. The coordination chemistry of the selenosalicylate ligand towards a variety of platinum(ii), palladium(ii), nickel(ii), gold(iii), gold(i), rhodium(iii), iridium(iii) and ruthenium(ii) centres was explored. X-ray crystal structure determinations were carried out on the complexes [Pt(SeC6H4CO2)(PPh3)2], [{(p-cym)Ru(SeC6H4CO2)}2] (p-cym = η6-p-cymene, CH3C6H4CH(CH3)2), [{Cp*Rh(SeC6H4CO2)}2] (Cp* = η5-C5Me5) and [Cp*Ir(SeC6H4CO2)(PPh3)], and comparisons are made with corresponding thiosalicylate complexes. The complexes were characterised by NMR spectroscopy as well as ESI mass spectrometry, which indicated a greater propensity for fragmentation including by selenium loss, compared to the thiosalicylate analogues. Hirshfeld surface analysis to visualise and quantify intermolecular interactions revealed the dominance of H⋯H contacts in [{(p-cym)Ru(SeC6H4CO2)}2] and [Cp*Ir(SeC6H4CO2)(PPh3)].

Protective effects and mechanism of chemical- and plant-based selenocystine against cadmium-induced liver damage

Although selenium (Se) and cadmium (Cd) often coexist naturally in the soil of China, the health risks to local residents consuming Se-Cd co-enriched foods are unknown. In the present study, we investigated the effects of chemical-based selenocystine (SeCys2) on cadmium chloride-induced human hepatocarcinoma (HepG2) cell injury and plant (Cardamine hupingshanensis)-derived SeCys2 against Cd-induced liver injury in mice. We found that chemical- and plant-based SeCys2 showed protective effects against Cd-induced HepG2 cell injury and liver damage in mice, respectively. Compared with Cd intervention group, co-treatment with chemical- or plant-based SeCys2 both alleviated liver toxicity and ferroptosis by decreasing ferrous iron, acyl-CoA synthetase long-chain (ACSL) family member 4, lysophosphatidylcholine acyltransferase 3, reactive oxygen species and lipid peroxide levels, and increasing ACSL3, peroxisome proliferator-activated receptor α, solute carrier family 7 member 11 (SLC7A11) and glutathione and glutathione peroxidase 4 (GPX4) levels. In conclusion, chemical- and plant-based SeCys2 alleviated Cd-induced hepatotoxicity and ferroptosis by regulating SLC7A11/GPX4 signaling and lipid peroxidation. Our findings indicate that potential Cd toxicity from consuming foods grown in Se- and Cd-rich soils should be re-evaluated. This study offers a new perspective for the development of SeCys2-enriched agricultural products.

Pro-vegetarian dietary patterns and essential and heavy metal exposure in children of 4-5-years from the INfancia y medio Ambiente cohort (INMA)

Dietary patterns provide a comprehensive assessment of food consumption, including essential nutrients and potential exposure to environmental contaminants. While pro-vegetarian (PVG) dietary patterns have shown health benefits in adults, their effects on children are less well studied. This study aims to explore the association between children's adherence to the most common PVG dietary patterns and their exposure to metals, assessed through urine concentration. In our study, we included a population of 723 children aged 4-5-years from the INfancia y Medio Ambiente (INMA) cohort in Spain. We calculated three predefined PVG dietary patterns, namely general (gPVG), healthful (hPVG), and unhealthful (uPVG), using dietary information collected through a validated Food Frequency Questionnaire. Urinary concentrations of various essential and heavy metals (Co, Cu, Zn, Se, Mo, Pb, and Cd) were measured using mass spectrometry. Additionally, urinary arsenic speciation, including arsenobetaine (AsB), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), and inorganic arsenic (iAs), was measured. The sum of urinary MMA and iAs was used to assess iAs exposure. We estimated primary (PMI) and secondary iAs methylation (SMI) indices. To explore the association between PVG dietary patterns in quintiles and metal exposure, we utilized multiple-adjusted linear regression models and the quantile g-computation approach. Compared with the lowest quintile, participants in the highest quintile of gPVG showed a 22.7% lower urinary Co (95% confidence interval (CI): -38.7; -1.98) and a 12.6% lower Se (95%CI: -22.9; -1.00) concentrations. Second quintile of adherence to hPVG was associated with a 51.7% lower urinary iAs + MMA concentrations (95%CI: -74.3; -8.61). Second quintile of adherence to an uPVG was associated with a 13.6% lower Se levels (95%CI: -22.9; -2.95) while the third quintile to this pattern was associated with 17.5% lower Mo concentrations (95%CI: -29.5; -2.95). The fourth quintile of adherence to gPVG was associated with a 68.5% higher PMI and a 53.7% lower SMI. Our study showed that adherence to a gPVG dietary pattern in childhood may modestly reduce the intakes of some essential metals such as Co and Se. Further investigations are warranted to explore any potential health implications.

Ionomic Variation Among Tissues in Fallow Deer (Dama dama) by Sex and Age

(1) In mammals, the mineral nutrient and trace elemental composition of the body - the ionome - differs among individuals. It has been hypothesized that these differences may be related to age and sex, both for ecotoxic and essential elements. (2) We investigated whether and how intraspecific ionomic variation is related to age and sex in Fallow deer (Dama dama). We tested the predictions that concentrations of ecotoxic elements increase with age, that ionomic variation is lower among young individuals than among older individuals, and that reproductive females (does) have the lowest concentrations of essential elements. (3) Culled animals of different sex and age were obtained from a single protected area. The animals were dissected to collect 13 tissues, and concentrations of 22 different elements were measured in a sample of each tissue. (4) We described substantial ionomic variation between individuals. Some of this variation was related to age and sex, as predicted. Based on the limited existing knowledge on chemical element allocation and metabolism in the body, sex-related differences were more difficult to interpret than age-related differences. Since reference values are absent, we could not judge about the consequences of the elemental values that we found. (5) More extensive ionomic surveys, based on a wide range of elements and tissues, are needed to enlarge the understanding of within-species ionomic variation and potential biological, ecological, and metabolic consequences.

Screening the critical protein subnetwork to delineate potential mechanisms and protective agents associated with arsenic-induced cutaneous squamous cell carcinoma: A toxicogenomic study

Recent studies show that complex mechanisms are involved in arsenic-induced malignant transformation of cells. This study aimed to decipher molecular mechanisms associated with arsenic-induced cutaneous squamous cell carcinoma (cSCC) and suggest potential protective factors. RNA-seq-based differentially expressed genes between arsenic-exposed human keratinocytes (HaCaT) and controls were used to construct a protein-protein interaction (PPI) network and discover critical subnetwork-based mechanisms. Protective compounds against arsenic toxicity were determined and their target interactions in the core sub-network were identified by the comparative toxicogenomic database (CTD). The binding affinity between the effective factor and target was calculated by molecular docking. A total of 15 key proteins were screened out as critical arsenic-responsive subnetwork (FN1, IL-1A, CCN2, PECAM1, FGF5, EDN1, FGF1, PXDN, DNAJB9, XBP1, ERN1, PDIA4, DNAJB11, FOS, PDIA6) and 7 effective protective agents were identified (folic acid, quercetin, zinc, acetylcysteine, methionine, catechin, selenium). The GeneMANIA predicted detailed interactions of the subnetwork and revealed terms related to unfolded protein response as the main processes. FN1, IL1A and CCN2, as top significant genes, had good docking affinity with folic acid and quercetin, as selected key compounds. Integration of gene expression and protein-protein interaction related to arsenic exposure in cSCC explored the potential mechanisms and protective agents.

Selenium Deficiency Causes Iron Death and Inflammatory Injury Through Oxidative Stress in the Mice Gastric Mucosa

Selenium (Se) is a trace element essential for the maintenance of normal physiological functions in living organisms. Oxidative stress is a state in which there is an imbalance between oxidative and antioxidant effects in the body. A deficiency of Se can make the body more inclined to oxidation, which can induce related diseases. The aim of this experimental study was to investigate the mechanisms by which Se deficiency affects the digestive system through oxidation. The results showed that Se deficiency treatment led to a decrease in the levels of GPX4 and antioxidant enzymes and an increase in the levels of ROS, MDA, and lipid peroxide (LPO) in the gastric mucosa. Oxidative stress was activated. Triple stimulation of ROS, Fe2+, and LPO induced iron death. The TLR4/NF-κB signaling pathway was activated, inducing an inflammatory response. The expression of the BCL family and caspase family genes was increased, leading to apoptotic cell death. Meanwhile, the RIP3/MLKL signaling pathway was activated, leading to cell necrosis. Taken together, Se deficiency can induce iron death through oxidative stress. Meanwhile, the production of large amounts of ROS activated the TLR4/NF-κB signaling pathway, leading to apoptosis and necrosis of the gastric mucosa.

Unravelling the in vitro and in vivo potential of selenium nanoparticles in Alzheimer's disease: A bioanalytical review

Alzheimer's disease (AD) is a devastating neurodegenerative disorder characterized by progressive cognitive decline and the accumulation of beta-amyloid plaques and tau tangles in the brain. Current therapies have limited efficacy, prompting the search for novel treatments. Selenium nanoparticles (SeNPs) have emerged as promising candidates for AD therapy due to their unique physicochemical properties and potential therapeutic effects. This review provides an overview of SeNPs and their potential application in AD treatment, as well as the main bioanalytical techniques applied in this field. SeNPs possess antioxidant and anti-inflammatory properties, making them potential candidates to combat the oxidative stress and neuroinflammation associated with AD. Moreover, SeNPs have shown the ability to cross the blood-brain barrier (BBB), allowing them to target brain regions affected by AD pathology. Various methods for synthesizing SeNPs are explored, including chemical, physical and biological synthesis approaches. Based on the employment of algae, yeast, fungi, and plants, green methods offer a promising and biocompatible alternative for SeNPs production. In vitro studies have demonstrated the potential of SeNPs in reducing beta-amyloid aggregation and inhibiting tau hyperphosphorylation, providing evidence of their neuroprotective effects on neuronal cells. In vivo studies using transgenic mouse models and AD-induced symptoms have shown promising results, with SeNPs treatment leading to cognitive improvements and reduced amyloid plaque burden in the hippocampus. Looking ahead, future trends in SeNPs research involve developing innovative brain delivery strategies to enhance their therapeutic potential, exploring alternative animal models to complement traditional mouse studies, and investigating multi-targeted SeNPs formulations to address multiple aspects of AD pathology. Overall, SeNPs represent a promising avenue for AD treatment, and further research in this field may pave the way for effective and much-needed therapeutic interventions for individuals affected by this debilitating disease.

Effects of selenium on biogeochemical cycles of cadmium in rice from flooded paddy soil systems in the alluvial Indus Valley of Pakistan

This study delves into the pollution status, assesses the effects of Se on Cd biogeochemical pathways, and explores their interactions in nutrient-rich paddy soil-rice ecosystems through 500 soil-rice samples in Pakistan. The results showed that 99.6 % and 12.8 % of soil samples exceeded the World Health Organization (WHO) allowable Se and Cd levels (7 and 0.35 mg/kg). In comparison, 23 % and 6 % of the grain samples exceeded WHO's allowable Se and Cd levels (0.3 and 0.2 mg/kg), respectively. Geographically Weighted Regression (GWR) model results further revealed spatial nonstationarity, confirming diverse associations between dependent variables (Se and Cd in rice grain) and independent variables from paddy soil and plant tissues (root and shoot), such as Soil Organic Matter (SOM), pH, Se, and Cd concentrations. High Se:Cd molar ratios (>1) and a negative correlation (r = -0.16, p < 0.01) between the Cd translocation factor (Cd in rice grain/Cd in root) and Se in roots suggest that increased root Se levels inhibit the transfer of Cd from roots to grains. The inverse correlation between Se and Cd in paddy grains was further characterized as Se deficiency, no risk, high Cd risk, Se risk, Cd risk, and Se-Cd co-exposure risk. There was no apparent risk for human co-consumption in 42.6 % of grain samples with moderate Se and low Cd. The remaining categories indicate differing degrees of risk. In the study area, 31 % and 20 % of grain samples with low Se and Cd indicate Se deficiency and risk, respectively. High Se and low Cd levels in rice samples suggest a potential hazard for severe Se exposure due to frequent rice consumption. This study not only systematically evaluates the pollution status of paddy-soil systems in Pakistan but also provides a reference to thoroughly contemplate the development of a scientific approach for evaluating human risks and the potential dangers associated with paddy soils and rice, specifically in regions characterized by low Se and low Cd concentrations, as well as those with moderate Se and high Cd concentrations. SYNOPSIS: This study is significant for understanding the effects of Se on Cd geochemical cycles and their interactions in paddy soil systems in Pakistan.

Selenium attenuated food borne cadmium-induced intestinal inflammation in red swamp crayfish (Procambarus clarkii) via regulating PI3K/Akt/NF-κB pathway

Selenium (Se), an indispensable micronutrient for living organisms, has been extensively studied for its heavy metal-detoxifying properties in diverse biological systems and tissues. Nevertheless, it is not entirely certain whether Se can effectively protect against Cadmium (Cd)-induced gut inflammation, especially in aquatic animals. In this study, we employed various approaches, including transcriptome profiling, histological examinations, assessment of antioxidant enzyme activities, and analysis of gut microbiota composition to investigate the effects on crayfish growth and intestinal health after exposure to dietary Cd (15 mg kg-1 diet) and Se (15 mg kg-1 diet) individually or in combination for 8 weeks. The results revealed that dietary Cd exposure resulted in reduced body weight and survival rates, along with an increased occurrence of intestinal inflammation. Nevertheless, Se supplementation proved effective in mitigating the adverse effects of Cd on growth and gut health. Se exhibited a remarkable ability to counteract the disruption of gut antioxidant abilities induced by dietary Cd, as evidenced by the observed increases in ROS and MDA contents, decrease in GSH levels, and inhibition of antioxidative enzyme activities. At the concentration of 6 mg kg-1 in the diet, Se was found beneficial for maintaining gut microbiota richness and diversity. Among them, Flavobacterium, Thermomonas, and Chloronema displayed a weak negative correlation with the rate of gut inflammation. Meanwhile, the levels of short chain fatty acids (SCFAs), including acetic acid (AA) and butanoic acid (BA), showed a significant increase in the Se-Cd group compared to the Cd-only group. Furthermore, transcriptome analysis exhibited significant responses of the PI3K/Akt and NF-κB pathways following crayfish exposure to dietary Se and Cd, either separately or in combination. In short, this study provides a new evidence regarding the molecular mechanisms through which Se could regulate the PI3K/Akt and NF-κB pathways, either directly or indirectly via ROS and SCFAs, thereby alleviating Cd-induced gut inflammation in crayfish.

Ameliorative Effects of Zn and Se Supplementation on Heavy Metal Mixture Burden via Increased Renal Metal Excretion and Restoration of Redoxo-Inflammatory Alterations

Heavy metals (HM)in the environment have provoked global attention because of its deleterious effects. This study evaluated the protection offered by Zn or Se or both against HMM-induced alterations in the kidney. Male Sprague Dawley rats were distributed into 5 groups of 7 rats each. Group I served as normal control with unrestricted access to food and water. Group II received Cd, Pb, and As (HMM) per oral daily for 60 days while groups III and IV received HMM in addition to Zn and Se respectively for 60 days. Group V received both Zn and Se in addition to HMM for 60 days. Metal accumulation in feces was assayed at days 0, 30, and 60 while accumulation in the kidney and kidney weight were measured at day 60. Kidney function tests, NO, MDA, SOD, catalase, GSH, GPx, NO, IL-6, NF-Κb, TNFα, caspase 3, and histology were assessed. There is a significant increase in urea, creatinine, and bicarbonate ions while potassium ions decreased. There was significant increase in renal function biomarkers, MDA, NO, NF-Κb, TNFα, caspase 3, and IL-6 while SOD, catalase, GSH, and GPx decrease. Administration of HMM distorted the integrity of the rat kidney, and co-treatment with Zn or Se or both offered reasonable protection suggesting that Zn or Se could be used as an antidot against the deleterious effects of these metals.

Selenium and zinc supplementation mitigates metals-(loids) mixture- mediated cardiopulmonary toxicity via attenuation of antioxidant, anti-inflammatory and antiapoptotic mechanisms in female Sprague Dawley rats

This study evaluated the cardiopulmonary protective effects of essential elements (Zn and Se) against heavy metals mixture (HMM) exposure. Twenty five female Sprague Dawley albino rats, divided in to five groups: controls were orally treated only with distilled water; next, group 2 was exposed to HMM with the following concentrations: 20 mg/kg of Pb body weight, 0.40 mg/kg of Hg, 0.56 mg/kg of Mn, and 35 mg/kg of Al. Groups 3, 4 and 5 were exposed to HMM and co-treated with zinc chloride (ZnCl2; 0.80 mg/kg), sodium selenite (Na2SeO3;1.50 mg/kg) and both zinc chloride and sodium selenite, respectively. The experiment lasted for 60 days. Afterwards animals were sacrificed, and we conduced biochemical and histopathological examination of the heart and lungs. HMM only exposed animals had an increased levels of malondialdehyde (MDA) and nitric oxide (NO), increased IL-6 and TNF-α, attenuated SOD, GPx, CAT and GSH and caspase 3 in the heart and lungs. HMM affected NF-kB and Nrf2 in the heart muscle with histomorphological alterations. Zn and Se attenuated adverse effects of HMM exposure. Essential element supplementation ameliorated heavy metal cardiopulmonary intoxication in rats.

Ultrasensitive Cd2+ detection based on biomimetic magneto-Au nano-urchin SERS chip fabricated using a 3D printed magnetic mold

Cadmium is a representative carcinogenic heavy metal. Because of the long biological half-life of cadmium, it is critical to prevent and detect cadmium inflow into the body. In this study, we developed the biomimetic magneto-gold nano-urchin (MGNU)-based surface-enhanced Raman scattering (SERS) chip for ultrasensitive detection of cadmium. The MGNU SERS chip was facilely fabricated using three-dimensional (3D) printed magnetic molds. The 3D printed magnetic molds were designed for contributing to (1) making hydrophobic/hydrophilic areas and (2) magnetic SERS enhancement by attracting the MGNUs. To validate the performance of the MGNU SERS chip, we conducted electromagnetic simulations and measurements of SERS efficiencies. Consequently, we detected cadmium ions up to 1.33 pM in distilled water. Moreover, we succeeded to detect cadmium ions in the real environmental samples up to 2.76 pM in the tap water and 14.21 pM in the human blood plasma, respectively. The MGNU SERS chip is a powerful SERS substrate that can be used in various spectrometer-based sensing platforms.

A systematic review and meta-analysis of validated analytical techniques for the determination of total selenium in foods and beverages

The intricate balance between the beneficial and harmful effects of selenium (Se) intake means that its quantification in food needs to be done correctly. Therefore, in this review, we systematized 105 articles to identify the most studied methodologies, analytical techniques, and food matrices. Among the analytical techniques employed, inductively coupled plasma mass spectrometry (ICP-MS) (n = 29) emerged as the most commonly used method. The most prevalent hydrolysis methodology to digest Se in food matrices involved the use of nitric acid combined with ultrasound, which improved both the yield and digestion time. Optimal recovery values were achieved when total Se quantification accounted for the sum of Se(IV) and Se(VI) (94.4-99.4%) and for SeCys (88-96.5%). These findings are relevant for advancing methodological approaches, and their results emphasize the importance of developing alternative, faster, and lower-cost protocols for Se quantification in foods and beverages.

Efficient and safe use of a slow-release Mn material for three sequential crops of rice in Cd-contaminated paddy soils

Traditional passivators reduce the effectiveness of Cd by ion exchange, chemisorption, and complexation in soil. However, traditional passivators have defects such as easy aging and poor durability, which not only reduce the treatment efficiency but also increase the risk of primary soil environmental pollution. For this reason, considering that Mn and Cd have physiological antagonism in rice, sepiolite-supported manganese ferrite (SMF) was prepared in this study to improve passivation persistence. The passivation mechanism, effect and duration of SMF were explored. The results showed that SMF has a dense and small pore structure and that the surface is rough, which provides abundant adsorption sites for Cd2+ adsorption. When the SMF adsorbs Cd2+, ions or functional groups in the material, such as MnOOH*, will exchange with Cd2+ to form Cd(OH)2 and other internal complexes. Indoor pure soil cultivation experiments showed that 0.1 % SMF can reduce the effective Cd content of soil by 41.32 %, demonstrating the efficiency of SMF. The three-crop rice experiments in pots showed that SMF could increase soil pH and continuously increase the content of available Mn in soil. Increasing the content of available Mn reduces the ability of rice to absorb Cd. In addition, the three-cropping rice experiments also indicated that the passivation effect of SMF materials on Cd-contaminated paddy fields was long-lasting and stable and that SMF is a more efficient and safe Cd passivation agent.

Factors by which global warming worsens allergic disease

Increased use of fossil fuels has led to global warming with concomitant increases in the severity and frequency of extreme weather events such as wildfires and sand and dust storms. These changes have led to increases in air pollutants such as particulate matter and greenhouse gases. Global warming is also associated with increases in pollen season length and pollen concentration. Particulate matter, greenhouse gases, and pollen synergistically increase the incidence and severity of allergic diseases. Other indirect factors such as droughts, flooding, thunderstorms, heat waves, water pollution, human migration, deforestation, loss of green space, and decreasing biodiversity (including microbial diversity) also affect the incidence and severity of allergic disease. Global warming and extreme weather events are expected to increase in the coming decades, and further increases in allergic diseases are expected, exacerbating the already high health care burden associated with these diseases. There is an urgent need to mitigate and adapt to the effects of climate change to improve human health. Human health and planetary health are connected and the concept of One Health, which is an integrated, unifying approach to balance and optimize the health of people, animals, and the environment needs to be emphasized. Clinicians are trusted members of the community, and they need to take a strong leadership role in educating patients on climate change and its adverse effects on human health. They also need to advocate for policy changes that decrease the use of fossil fuels and increase biodiversity and green space to enable a healthier and more sustainable future.

A Clinical Perspective on Arsenic Exposure and Development of Atherosclerotic Cardiovascular Disease

Cardiovascular risk has traditionally been defined by modifiable and non-modifiable risk factors, such as tobacco use, hyperlipidemia, and family history. However, chemicals and pollutants may also play a role in cardiovascular disease (CVD) risk. Arsenic is a naturally occurring element that is widely distributed in the Earth's crust. Inorganic arsenic (iAs) has been implicated in the pathogenesis of atherosclerosis, with chronic high-dose exposure to iAs (> 100 µg/L) being linked to CVD; however, whether low-to-moderate dose exposures of iAs (< 100 µg/L) are associated with the development of CVD is unclear. Due to limitations of the existing literature, it is difficult to define a threshold for iAs toxicity. Studies demonstrate that the effect of iAs on CVD is far more complex with influences from several factors, including diet, genetics, metabolism, and traditional risk factors such as hypertension and smoking. In this article, we review the existing data of low-to-moderate dose iAs exposure and its effect on CVD, along with highlighting the potential mechanisms of action.

A combination of selenium and Bacillus subtilis improves the quality and flavor of meat and slaughter performance of broilers

This study aimed to investigate the effects of the combination of selenium and Bacillus subtilis (Se-BS) on the quality and flavor of meat and slaughter performance of broilers. A total of 240 one-day-old Arbor Acres broilers were randomly allotted to four treatments of a basal diet supplemented with no selenium (control), sodium selenite (SS), BS, or Se-BS and raised for 42 days. Compared with the control group, Se-BS significantly increased the carcass weight, the half-eviscerated weight, the completely eviscerated weight, the carcass rate, and redness in broiler muscles; improved the antioxidant state by increasing glutathione peroxidase (GPx) and glutathione S-transferase activities, the total antioxidant capacity, and GPx-1 and thioredoxin reductase 1 messenger RNA (mRNA) levels; promoted biological activity by increasing the contents of glutamate, phenylalanine, lysine, and tyrosine; and increased Se and five types of nitrogenous volatile substances in muscles. On the other hand, Se-BS treatment decreased the shear force, drip loss, and the malondialdehyde, glutathione, and lead contents in muscles. Se-BS exerted a better effect on slaughter performance, the physicochemical quality of meat, the redox status, the amino acid contents, the trace element contents, and volatile substances compared with SS and BS. In conclusion, Se-BS had a positive effect on the quality and flavor of meat and slaughter performance of broilers, suggesting that Se-BS may be a beneficial feed additive.

Selenium nanoparticles: Enhanced nutrition and beyond

Selenium is a trace nutrient that has both nutritional and nutraceutical functions, whereas narrow nutritional range of selenium intake limits its use. Selenium nanoparticles (SeNPs) are less toxic and more bioavailable than traditional forms of selenium, suggesting that SeNPs have the potential to replace traditional selenium in food industries and/or biomedical fields. From the perspective of how SeNPs can be applied in health area, this review comprehensively discusses SeNPs in terms of its preparation, nutritional aspect, detoxification effect of heavy metals, nutraceutical functions and anti-pathogenic microorganism effects. By physical, chemical, or biological methods, inorganic selenium can be transformed into SeNPs which have increased stability and bioavailability as well as low toxicity. SeNPs are more effective than traditional selenium form in synthesizing selenoproteins like glutathione peroxidases. SeNPs can reshape the digestive system to facilitate digestion and absorption of nutrients. SeNPs have shown excellent potential to adjunctively treat cancer patients, enhance immune system, control diabetes, and prevent rheumatoid arthritis. Additionally, SeNPs have good microbial anti-pathogenic effects and can be used with other antimicrobial agents to fight against pathogenic bacteria, fungi, or viruses. Development of novel SeNPs with enhanced functions can greatly benefit the food-, nutraceutical-, and biomedical industries.

Ecotoxicology applied to conservation: Potential negative metal and metalloid contamination effects on the homeostatic balance of the critically endangered Brazilian guitarfish, Pseudobatos horkelii (Elasmobranchii: Rhinobatidae)

Metal contamination poses a significant threat to elasmobranchs, underscoring the need for targeted conservation approaches. The critically endangered Brazilian guitarfish, Pseudobatos horkelii, confronts an array of challenges, notably overexploitation, putting its survival at risk. Our study investigated the potential toxicity arising from arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) contamination across various adult guitarfish tissues from southeastern Brazil. Serological stress indicators, nutritional metabolites, and creatinine, an organ function marker, were also assessed, and Selenium (Se) levels were also investigated for possible protective effects. Our investigation unveiled significant correlations between metal concentrations and the determined physiological markers, shedding light on potential adverse effects. Remarkably, six correlations were indicative of how Hg and Pb negatively impact hepatic metabolite assimilation, while As was shown to influence renal phosphorus dynamics, Cd to affect rectal gland phosphorus regulation, and Pb to influence creatinine production in muscle tissue. Furthermore, Se demonstrated protective properties against Cd, Hg, and Pb, suggesting a role in alleviating the toxicity of these elements. Despite probable protective Se influences, the detected elemental interactions still suggest potential for organ impairment. These findings gain heightened significance within the context of the cumulative stressors faced by the Brazilian guitarfish, with metal contamination exhibiting the capacity to erode this species resilience against both anthropogenic and environmental pressures, thereby disrupting systemic equilibrium and jeopardizing wild populations. By investigating the intricate balance between metal accumulation and physiological consequences, our study contributes with crucial insights into potential conservation strategy formulations towards pollution for this critically endangered elasmobranch species.

Toxic Kidney Damage in Rats Following Subchronic Intraperitoneal Exposure to Element Oxide Nanoparticles

Chronic diseases of the urogenital tract, such as bladder cancer, prostate cancer, reproductive disorders, and nephropathies, can develop under the effects of chemical hazards in the working environment. In this respect, nanosized particles generated as by-products in many industrial processes seem to be particularly dangerous to organs such as the testes and the kidneys. Nephrotoxicity of element oxide particles has been studied in animal experiments with repeated intraperitoneal injections of Al2O3, TiO2, SiO2, PbO, CdO, CuO, and SeO nanoparticles (NPs) in total doses ranging from 4.5 to 45 mg/kg body weight of rats. NPs were synthesized by laser ablation. After cessation of exposure, we measured kidney weight and analyzed selected biochemical parameters in blood and urine, characterizing the state of the excretory system. We also examined histological sections of kidneys and estimated proportions of different cells in imprint smears of this organ. All element oxide NPs under investigation demonstrated a nephrotoxic effect following subchronic exposure. Following the exposure to SeO and SiO2 NPs, we observed a decrease in serum creatinine and urea, respectively. Exposure to Al2O3 NPs caused an increase in urinary creatinine and urea, while changes in total protein were controversial, as it increased under the effect of Al2O3 NPs and was reduced after exposure to CuO NPs. Histomorphological changes in kidneys are associated with desquamation of the epithelium (following the exposure to all NPs except those of Al2O3 and SiO2) and loss of the brush border (following the exposure to all NPs, except those of Al2O3, TiO2, and SiO2). The cytomorphological evaluation showed greater destruction of proximal sections of renal tubules. Compared to the controls, we observed statistically significant alterations in 42.1% (8 of 19) of parameters following the exposure to PbO, CuO, and SeO NPs in 21.1% (4 of 19)-following that, to CdO and Al2O3 NPs-and in 15.8% (3 of 19) and 10.5% (2 of 19) of indicators, following the exposure to TiO2 and SiO2 nanoparticles, respectively. Histomorphological changes in kidneys are associated with desquamation of epithelium and loss of the brush border. The cytomorphological evaluation showed greater destruction of proximal sections of renal tubules. The severity of cyto- and histological structural changes in kidneys depends on the chemical nature of NPs. These alterations are not always consistent with biochemical ones, thus impeding early clinical diagnosis of renal damage. Unambiguous ranking of the NPs examined by the degree of their nephrotoxicity is difficult. Additional studies are necessary to establish key indicators of the nephrotoxic effect, which can facilitate early diagnosis of occupational and nonoccupational nephropathies.

Urinary arsenic and spontaneous pregnancy loss - a hypothesis-generating case-control investigation in western Romania

Arsenic occurs as a natural contaminant of drinking water supplies in arsenic endemic areas, posing a threat to public health. Our aim was to evaluate the relationship between urinary arsenic concentrations and spontaneous pregnancy loss in a population with low-moderate level drinking water arsenic exposure (mostly <10 μg/L). We enrolled 150 women with incident spontaneous pregnancy losses and 150 controls with ongoing pregnancies matched by gestational age. We measured arsenic species in urine using high performance liquid chromatography paired to inductively coupled plasma mass spectrometry. Urinary arsenic was not related to spontaneous pregnancy loss in conditional logistic regression models adjusted for confounding factors. However, a 10 μg/L increase in urinary arsenic (III + V) salt concentrations was associated with 8.00-fold (95% CI: 0.68, 3.35 × 105) greater odds of spontaneous loss among women using prenatal vitamins in an interaction model (P for interaction = 0.07), although the effect estimate was imprecise. In an additional interaction model, prenatal vitamin use was associated with lower odds of loss (OR = 0.30; 95% CI: 0.13, 0.66), although the association was diminished in the presence of a 10 μg/L increase in urinary inorganic arsenic (OR = 0.44; 95% CI: 0.70, 3.22). Total urinary arsenic was associated with 1.48-fold (95% CI: 0.20, 11.35) greater odds for loss among women with urinary cotinine >50 μg/L in another interaction model (P for interaction = 0.07). These results suggest a potential modest increase in the odds of pregnancy loss associated with increased total urinary arsenic among women smoking during pregnancy (urinary cotinine >50 μg/L). Prenatal vitamin use may act as a protective factor for arsenic exposure associated pregnancy loss, but appears to be less protective with increasing urinary inorganic arsenic concentrations.

Selenium alleviates cadmium-induced oxidative stress, endoplasmic reticulum stress, and apoptosis in L8824 cells

Cadmium (Cd) is a toxic pollutant in industrial production that induces organ damage and apoptosis, While, selenium (Se) has the biological function of antagonizing Cd toxicity. Hence, to gain further insight into the protective mechanisms of selenium against Cd-induced damage in Ctenopharyngodon idella liver (L8824) cells, L8824 were exposed to 5 μM, 15 μM, 25 μM cadmium chloride for 24 h after pre-incubation with 25 μM sodium selenite for 9 h. Cell proliferation and morphological changes, the levels of reactive oxygen species (ROS) and antioxidant enzyme activity, mitochondrial membrane potential (MMP), endoplasmic reticulum stress (ERS)-related pathway genes expression, intracellular calcium levels and apoptosis were assessed to explore the protective effect of selenium in Cd-induced L8824 cell damage. The results showed that Cd caused decreased cell viability, ROS accumulation, reduced activity of antioxidant enzymes (SOD, CAT GPx and T-AOC) and apoptosis in L8824 cells. The incubation of Se prominently ameliorated cell proliferation, activated the Keap1-Nrf2 pathway, and restored antioxidant enzyme activity. Furthermore, the expression of grp78, perk, eif-2α, atf4, chop bax, jnk, caspase-3 and caspase-9 was significantly upregulated after Cd exposure, while the expression of bcl-2 was significantly downregulated. Se supplementation alleviated Cd-induced ERS and apoptosis. Moreover, Cd-induced elevation of intracellular Ca2+ levels were alleviated by dantrolene and 2-APB, suggesting that intracellular calcium disorders were caused by Ca2+ released by RyR and IP3R-mediated ER. The results of this study suggested that Cd could induce oxidative stress, ERS, mitochondrial damage and evoke apoptosis, whereas Se had protective effects in preventing Cd induced damage by inhibiting ERS, maintaining intracellular calcium homeostasis, enhancing the antioxidant capacity of L8824 cells and downregulating the Keap1/Nrf2 pathway.

A critical analysis of sources, pollution, and remediation of selenium, an emerging contaminant

Selenium (Se) is an essential metalloid and is categorized as emerging anthropogenic contaminant released to the environment. The rise of Se release into the environment has raised concern about its bioaccumulation, toxicity, and potential to cause serious damages to aquatic and terrestrial ecosystem. Therefore, it is extremely important to monitor Se level in environment on a regular basis. Understanding Se release, anthropogenic sources, and environmental behavior is critical for developing an effective Se containment strategy. The ongoing efforts of Se remediation have mostly emphasized monitoring and remediation as an independent topics of research. However, our paper has integrated both by explaining the attributes of monitoring on effective scale followed by a candid review of widespread technological options available with specific focus on Se removal from environmental media. Another novel approach demonstrated in the article is the presentation of an overwhelming evidence of limitations that various researchers are confronted with to overcome achieving effective remediation. Furthermore, we followed a holistic approach to discuss ways to remediate Se for cleaner environment especially related to introducing weak magnetic field for ZVI reactivity enhancement. We linked this phenomenal process to electrokinetics and presented convincing facts in support of Se remediation, which has led to emerge 'membrane technology', as another viable option for remediation. Hence, an interesting, innovative and future oriented review is presented, which will undoubtedly seek attention from global researchers.

Toxicological mechanism of cadmium in the clam Ruditapes philippinarum using combined ionomic, metabolomic and transcriptomic analyses

Cadmium (Cd) contamination in marine environment poses great risks to the organisms due to its potential adverse effects. In the present study, the toxicological effects and mechanisms of Cd at environmentally relevant concentrations (5 and 50 μg/L) on clam Ruditapes philippinarum after 21 days were investigated by combined ionomic, metabolomic, and transcriptomic analyses. Results showed that the uptake of Cd significantly decreased the concentrations of Cu, Zn, Sr, Se, and Mo in the whole soft tissue from 50 μg/L Cd-treated clams. Significantly negative correlations were observed between Cd and essential elements (Zn, Sr, Se, and Mo). Altered essential elements homeostasis was associated with the gene regulation of transport and detoxification, including ATP-binding cassette protein subfamily B member 1 (ABCB1) and metallothioneins (MT). The crucial contribution of Se to Cd detoxification was also found in clams. Additionally, gene set enrichment analysis showed that Cd could interfere with proteolysis by peptidases and decrease the translation efficiency at 50 μg/L. Cd inhibited lipid metabolism in clams and increased energy demand by up-regulating glycolysis and TCA cycle. Osmotic pressure was regulated by free amino acids, including alanine, glutamate, taurine, and homarine. Meanwhile, significant alterations of some differentially expressed genes, such as dopamine-β-hydroxylase (DBH), neuroligin (NLGN), NOTCH 1, and chondroitin sulfate proteoglycan 1 (CSPG1) were observed in clams, which implied potential interference with synaptic transmission. Overall, through integrating multiple omics, this study provided new insights into the toxicological mechanisms of Cd, particularly in those mediated by dysregulation of essential element homeostasis.

Determinants of oxidative stress among indigenous populations in Northern Laos: Trace element exposures and dietary patterns

OBJECTIVES

To investigate determinants of oxidative stress in an indigenous population, we examined associations of trace element exposures and dietary patterns with three oxidative stress-related biomarkers among indigenous populations in Northern Laos.

METHODS

This cross-sectional study included 341 adults from three villages with different levels of modernization. We used three oxidative stress-related biomarkers: urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostane concentrations, which were measured using liquid chromatography-tandem mass spectrometry, and blood telomere lengths, which were measured using a quantitative polymerase chain reaction method. We used multilevel analysis to examine associations of urinary arsenic, cadmium, and selenium concentrations, their interaction terms, and wild-plant-food scores (principal component scores calculated from food consumption frequencies) with oxidative stress-related biomarkers.

RESULTS

Urinary arsenic and cadmium concentrations were positively associated with urinary 8-isoprostane concentrations. Urinary selenium concentrations were positively associated with urinary 8-OHdG concentrations. Interaction terms ([arsenic or cadmium] × selenium) showed negative associations with urinary 8-OHdG and 8-isoprostane concentrations, respectively. Urinary cadmium concentrations were negatively associated with telomere lengths. Wild-plant-food scores did not exhibit associations with oxidative stress-related biomarkers.

CONCLUSION

Our findings imply that exposure to arsenic and cadmium is associated with greater oxidative lipid damage, whereas selenium may attenuate arsenic-induced oxidative DNA damage and cadmium-induced oxidative lipid damage. Cadmium exposure may accelerate telomere attrition. Trace element exposure may be a determinant of oxidative stress among indigenous populations in Northern Laos.

Morphological and Physiological Indicators and Transcriptome Analyses Reveal the Mechanism of Selenium Multilevel Mitigation of Cadmium Damage in Brassica juncea

Cadmium (Cd) is a common agricultural soil pollutant, which does serious harm to the environment and the human body. In this study, Brassica juncea was treated with different concentrations of CdCl₂ and Na₂SeO₃. Then, physiological indexes and transcriptome were measured to reveal the mechanisms by which Se reduces the inhibition and toxicity of Cd in B. juncea. The results showed that Se alleviated the inhibitive Cd effects on seedling biomass, root length, and chlorophyll, and promoted the adsorption of Cd by pectin and lignin in the root cell wall (CW). Se also alleviated the oxidative stress induced by Cd, and reduced the content of MDA in cells. As a result, SeCys and SeMet alleviated the transport of Cd to the shoots. Transcriptome data showed that the bivalent cation transporter MPP and ABCC subfamily participated in the separation of Cd in vacuoles, CAL1 was related to the chelation of Cd in the cytoplasm of cells, and ZIP transporter 4 reduced the transport of Cd to the shoots. These results indicated that Se alleviated the damage of Cd in plants and decreased its transport to the shoots by improving the antioxidant system, enhancing the ability of the CW to adsorb Cd, reducing the activity of Cd transporters, and chelating Cd.

Quantum dots are time bomb: Multiscale toxicological study

The use of quantum dots has spread widely into many applications. Works on the study of quantum dots on living organisms have had conflicting results on toxicity. There are no full-scale long-term toxicological studies with multiple administration of quantum dots. Understanding the toxicity of quantum dots is still limited. Here we present data on the effects of quantum dots on animals. In this work for the first time, it is shown that at a single administration of quantum dots in the body they have moderate species-specific toxicity, but repeated administration of quantum dots for 14 days even in the amount of 0.5 mg/kg leads to a delayed not completely irreversible hematotoxic effect, delayed irreversible disorders of barrier function of the liver, irreversible nephrotoxic effect, and to pathological changes in the thymus, kidneys and spleen. Administration of quantum dots in the amount of 2.5 mg/kg for 14 days leads to irreversible changes in the lungs, liver, spleen, kidneys and thyroid gland. This phenomenon is based on immunological reactions. On the one hand, these data confirm that quantum dots at a single administration can show relatively low toxicity. On the other hand, they cause to a delayed irreversible organ and tissue damage when repeatedly administered to the body even in small quantities. This study demonstrates that quantum dots are not as low in toxicity as previously thought to be and pose a serious risk when entering living organisms. Detecting and treating poisoning using standard methods of diagnosis and treatment of heavy metal poisoning may not be effective. This study demonstrates that toxic effects of quantum dots on a living body are quite complex and cannot be generalized based on previously reported assumptions.

Selenium and mercury concentrations, Se:Hg molar ratios and their effect on the antioxidant system in wild mammals

The aim of this study was to a) evaluate the concentration of Se and Hg and their relationship in the tissues of 4 species of wild mammals, including Se:Hg molar ratios, and b) evaluate the effect of the analysed elements and their mutual proportions expressed as Se:Hg molar ratio, on the antioxidant system in the tissues of the tested animals. The study was performed on 31 animals belonging to four species: wild boar, red fox, roe deer, brown hare. Determination of Hg in liver, kidney and muscle of animals was performed using an AMA 254 mercury analyser. Total Se concentrations were determined using the spectrofluorometric method. In omnivores demonstrated higher Se concentrations in all analysed organs compared to the herbivores. The highest concentration of Hg was found in the kidneys of the tested animals, and the lowest in the muscles. High and moderate correlation between Se and Hg was observed in the liver of omnivorous, while in herbivores this correlation was weak. In all analysed samples, the Se:Hg molar ratios were above 1 (min: liver 5.9, max: kidney 110). Generally, the highest Se:Hg ratio values were found in kidney and the lowest in liver of tested animals. No significant correlation was found between GPx, GST and SOD activity and Se or Hg concentration in analysed organs. But it was observed that Se:Hg molar was negatively correlated with CAT activity in the most samples. The obtained results may suggest that omnivorous animals demonstrate greater Hg sequestration in the liver than herbivores, which has been proposed as one of the mechanisms of Se antagonistic action towards Hg. The ratio between Se and Hg, rather than the concentration of these elements in organs, affected the antioxidant status in the animal organism, specifically the CAT activity.