Journal articles on the topic 'Mercury as well as arsenic'

The conserved Target Of Rapamycin (TOR) growth control signaling pathway is a major regulator of genes required for protein synthesis. The ubiquitous toxic metalloid arsenic, as well as mercury and nickel, are shown here to efficiently inhibit the rapamycin-sensitive TORC1 (TOR complex 1) protein kinase. This rapid inhibition of the TORC1 kinase is demonstrated in vivo by the dephosphorylation and inactivation of its downstream effector, the yeast S6 kinase homolog Sch9. Arsenic, mercury, and nickel cause reduction of transcription of ribosome biogenesis genes, which are under the control of Sfp1, a TORC1-regulated transcriptional activator. We report that arsenic stress deactivates Sfp1 as it becomes dephosphorylated, dissociates from chromatin, and exits the nucleus. Curiously, whereas loss of SFP1 function leads to increased arsenic resistance, absence of TOR1 or SCH9 has the opposite effect suggesting that TORC1 has a role beyond down-regulation of Sfp1. Indeed, we show that arsenic activates the transcription factors Msn2 and Msn4 both of which are targets of TORC1 and protein kinase A (PKA). In contrast to TORC1, PKA activity is not repressed during acute arsenic stress. A normal level of PKA activity might serve to dampen the stress response since hyperactive Msn2 will decrease arsenic tolerance. Thus arsenic toxicity in yeast might be determined by the balance between chronic activation of general stress factors in combination with lowered TORC1 kinase activity.

This study identified the levels of arsenic, cadmium, mercury, and lead in 15 species of commonly consumed fish in Thailand (7 freshwater species, 8 marine species), as well as the risk of these toxic elements for consumers. Inductively coupled plasma mass spectrometry (ICP-MS-MS) was used to identify toxic elements, while an exposure assessment was conducted by applying consumption amounts from the national food consumption survey to the toxic element contents in the fish samples. The results showed that the fish contained arsenic ranging from less than the limit of detection (LOD) to 8.51 mg/kg fresh weight (FW), cadmium ranging from the LOD to 0.04 mg/kg FW, and mercury ranging from the limit of quantitation (LOQ) to 0.38 mg/kg FW. Lead was found in small amounts (<LOQ) when compared to the Codex and Thailand’s standards. Only grouper had a higher mercury content (0.55 mg/kg FW) than that of the Codex standard, but it was lower than the notification requirement of Thailand’s Ministry of Public Health. Based on the estimated daily intake scenario, the consumption of most fish species posed a low risk of concern in terms of cadmium and lead. A high risk of concern was found for arsenic exposure, with the exception of long, non-scaly fish (catfish and dory). Marine fish, with the exception of Indo-Pacific mackerel, also posed a high risk of mercury exposure, but only in the case of a high mercury content, high consumption, or both. For a high arsenic content with high consumption or both, children aged 0–5.9 years were at a high risk of concern. Food safety authorities should regularly monitor the levels of toxic element contamination in high-risk food products.

Non-essential metals are extremely toxic to living organisms, posing significant health risks, particularly in developing nations where they are a major contributor to illness and death. Although their toxicity is widely acknowledged, the mechanisms by which they are regulated within human cells remain incompletely understood. Specifically, the role of membrane transporters in mediating heavy metal toxicity is not well comprehended. Our study demonstrates how specific transporters can modulate the toxicity of cadmium, mercury, and the metalloid arsenic in human cells. Using CRISPR/Cas9 loss-of-function screens, we found that the multidrug resistance protein MRP1/ABCC1 provided protection against toxicity induced by arsenic and mercury. In addition, we found that SLC39A14 and SLC30A1 increased cellular sensitivity to cadmium. Using a reporter cell line to monitor cellular metal accumulation and performing a cDNA gain-of-function screen, we were able to clarify the function of SLC30A1 in controlling cadmium toxicity through the modulation of intracellular zinc levels. This transporter-wide approach provides new insights into the complex roles of membrane transporters in influencing the toxicity of arsenic, cadmium, and mercury in human cell lines.

In the current decades, the increasing presence of metallic contaminants in water for human consumption has become a major public health concern. This concern is even more pronounced in rural areas such as in the Town Halls of Agbangnizoun and Za-Kpota where the majority of households use surface water, wells and tanks to satisfy their daily drinking water needs, without any prior treatment, due to the low level of access to drinking water supplied by the State. This study aims at assessing the levels of contamination of these resources in mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (As). The mercury was determined using the cold vapor technique by the Direct Mercury Analyzer (DMA-80) while lead and cadmium were analyzed by molecular absorption spectrophotometry by the DR 3900. The Arsenic was extracted by distillation using the silver diethyldithiocarbamate method then measured by molecular spectrophotometry technique. The results show that surface waters contain great quantities of metals than well and cistern waters. Lead (220.97 ± 9.45 µg/L) and cadmium (20.13 ± 0.17 µg/L) in surface waters have levels above WHO guidelines and Bénin standards. On the other hand, there is no significant difference between the metal concentrations of well and cistern waters at the 5% threshold compared to the borehole water (witness sample). Significant correlations are established between toxic metals (Pb and Cd) and physical parameters (turbidity and suspended matters) at the threshold of 1 %. As for mercury (Hg) and arsenic (As), the concentrations are very lower than these of Cd and Pb and below the quantification limit of the device. These results confirm that the surface waters consumed by the populations of the Town Halls of Agbangnizoun and Za-Kpota do not respect drinking water standards.

Our studies have indicated that the relative concentration of Se or Hg to As in urine and blood positively correlates with percentage of inorganic arsenic (% Inorg-As) and percentage of monomethlyarsonic acid [% MMA (V)]. We also found a negative correlation with percentage of dimethylarsinic acid [% DMA (V)] and the ratio of % DMA (V) to % MMA (V). In another study, we found that a group of proteins were significantly over expressed and conversely other groups were under-expressed in tissues in Na-As (III) treated hamsters.
 Introduction.Inorganic arsenic (Inorg-As) in drinking water.One of the largest public health problems at present is the drinking of water containing levels of Inorg-As that are known to be carcinogenic. At least 200 million people globally are at risk of dying because of arsenic (As) in their drinking water1-3. The chronic ingestion of Inorg-As can results in skin cancer, bladder cancer, lung cancer, and cancer of other organs1-3. The maximum contamination level (MCL) of U.S. drinking water for arsenic is 10 ug/L. The arsenic related public health problem in the U.S. is not at present anywhere near that of India4, Bangladesh4, and other countries5.
 Metabolism and toxicity of Inorg-As and arsenic species.Inorg-As is metabolized in the body by alternating reduction of pentavalent arsenic to trivalent form by enzymes and addition of a methyl group from S-adenosylmethionine6, 7; it is excreted mainly in urine as DMA (V)8. Inorganic arsenate [Inorg-As (V)]is biotransformed to Inorg-As (III), MMA (V), MMA (III), DMA (V), and DMA (III)6(Fig. 1). Therefore, the study of the toxicology of Inorg-As (V) involves at least these six chemical forms of arsenic. Studies reported the presence of 3+ oxidation state arsenic biotransformants [MMA (III) and DMA (III)] in human urine9and in animal tissues10. The MMA (III) and DMA (III) are more toxic than other arsenicals11, 12. In particular MMA (III) is highly toxic11, 12. In increased % MMA in urine has been recognized in arsenic toxicity13. In addition, people with a small % MMA in urine show less retention of arsenic14. Thus, the higher prevalence of toxic effects with increased % MMA in urine could be attributed to the presence of toxic MMA (III) in the tissue. Previous studies also indicated that males are more susceptible to the As related skin effects than females13, 15. A study in the U.S population reported that females excreted a lower % Inorg-As as well as % MMA, and a higher % DMA than did males16.
 Abbreviation: SAM, S-adenosyl-L-methionine; SAHC, S-adenosyl-L-homocysteine.
 Differences in susceptibility to arsenic toxicity might be manifested by differences in arsenic metabolism among people. Several factors (for examples, genetic factors, sex, duration and dosage of exposure, nutritional and dietary factors, etc.) could be influence for biotransformation of Inorg-As,6, 17 and other unknown factors may also be involved.
 The interaction between As, Se, and Hg.The toxicity of one metal or metalloid can be dramatically modulated by the interaction with other toxic and essential elements18. Arsenic and Hg are toxic elements, and Se is required to maintain good health19. But Se is also toxic at high levels20. Recent reports point out the increased risk of squamous cell carcinoma and non-melanoma skin cancer in those treated with 200 ug/day of selenium (Nutritional Prevention of Cancer Trial in the United States)21. However, it is well known that As and Se as well as Se and Hg act as antagonists22. It was also reported that Inorg-As (III) influenced the interaction between selenite and methyl mercury23. A possible molecular link between As, Se, and Hg has been proposed by Korbas et al. (2008)24. The identifying complexes between the interaction of As and Se, Se and Hg as well as As, Se, and Hg in blood of rabbit are shown in Table 1.
 Influence of Se and Hg on the metabolism of Inorg-As.The studies have reported that Se supplementation decreased the As-induced toxicity25, 26. The concentrations of urinary Se expressed as ug/L were negatively correlated with urinary % Inorg-As and positively correlated with % DMA27. The study did not address the urinary creatinine adjustment27. Other researchers suggested that Se and Hg decreased As methylation28-31(Table 2). They also suggested that the synthesis of DMA from MMA might be more susceptible to inhibition by Se (IV)29 as well as by Hg (II)30,31 compared to the production of MMA from Inorg-As (III). The inhibitory effects of Se and Hg were concentration dependent28-31.
 The literature suggests that reduced methylation capacity with increased % MMA (V), decreased % DMA (V), or decreased ratios of % DMA to % MMA in urine is positively associated with various lesions32. Lesions include skin cancer and bladder cancer32. The results were obtained from inorganic arsenic exposed subjects32. Our concern involves the combination of low arsenic (As) and high selenium (Se) ingestion. This can inhibit methylation of arsenic to take it to a toxic level in the tissue.
 Dietary sources of Se and Hg.Global selenium (Se) source are vegetables in the diet. In the United States, meat and bread are the common source. Selenium deficiency in the US is rare. The US Food and Drug Administration (FDA) has found toxic levels of Se in dietary supplements, up to 200 times greater than the amount stated on the label33. The samples contained up to 40,800 ug Se per recommended serving.
 For the general population, the most important pathway of exposure to mercury (Hg) is ingestion of methyl mercury in foods. Fish (including tuna, a food commonly eaten by children), other seafood, and marine mammals contain the highest concentrations. The FDA has set a maximum permissible level of 1 ppm of methyl mercury in the seafood34. The people also exposed mercury via amalgams35.
 Proteomic study of Inorg-As (III) injury.Proteomics is a powerful tool developed to enhance the study of complex biological system36. This technique has been extensively employed to investigate the proteome response of cells to drugs and other diseases37, 38. A proteome analysis of the Na-As (III) response in cultured lung cells found in vitro oxidative stress-induced apoptosis39. However, to our knowledge, no in vivo proteomic study of Inorg-As (III) has yet been conducted to improve our understanding of the cellular proteome response to Inorg-As (III) except our preliminary study 40.
 Preliminary Studies: Results and DiscussionThe existing data (Fig. 1) from our laboratory and others show the complex nature of Inorg-As metabolism. For many years, the major way to study, arsenic (As) metabolism was to measure InorgAs (V), Inorg-As (III), MMA (V), and DMA (V) in urine of people chronically exposed to As in their drinking water. Our investigations demonstrated for the first time that MMA (III) and DMA (III) are found in human urine9. Also we have identified MMA (III) and DMA (III) in the tissues of mice and hamsters exposed to sodium arsenate [Na-As (V)]10, 41.
 Influence of Se as well as Hg on the As methyltransferase.We have reported that Se (IV) as well as mercuric chloride (HgCl2) inhibited As (III) methyltransferase and MMA (III) methyltransferase in rabbit liver cytosol. Mercuric chloride was found to be a more potent inhibitor of MMA (III) methyltransferase than As (III) methyltransferase30. These results suggested that Se and Hg decreased arsenic methylation. The inhibitory effects of Se and Hg were concentration dependent30.
 Influence of Se and Hg in urine and blood on the percentage of urinary As metabolites.Our human studies indicated that the ratios of the concentrations of Se or Hg to As in urine and blood were positively correlated with % Inorg-As and % MMA (V). But it negatively correlated with % DMA (V) and the ratios of % DMA (V) to % MMA (V) in urine of both males and females (unpublished data) (Table 3). These results confirmed that the inhibitory effects of Se as well as Hg for the methylation of Inorg-As in humans were concentration dependent. We also found that the concentrations of Se and Hg were negatively correlated with % Inorg-As and % MMA (V). Conversely it correlated positively with % DMA (V) and the ratios of % DMA (V) to % MMA (V) in urine of both sexes (unpublished data). These correlations were not statistically significant when urinary concentrations of Se and Hg were adjusted for urinary creatinine (Table 3). Interactions of As, Se, Hg and its relationship with methylation of arsenic are summarized in Figure 2.
 Sex difference distribution of arsenic species in urine.Our results indicate that females have more methylation capacity of arsenic as compared to males. In our human studies (n= 191) in Mexico, we found that females (n= 98) had lower % MMA (p<0.001) and higher % DMA (p=0.006) when compared to males (n= 93) (Fig. 3). The means ratio of % MMA (V) to % Inorg-As and % DMA (V) to %MMA (V) were also lower (p<0.05) and higher (p<0.001), respectively in females compared to males.
 The protein expression profiles in the tissues of hamsters exposed to Na-As (III).In our preliminary studies40, hamsters were exposed to Na-As (III) (173 pg/ml as As) in their drinking water for 6 days and control hamsters were given only the water used to make the solutions for the experimental animals. After DIGE (Two-dimensional differential in gel electrophoresis) and analysis by the DeCyder software, several protein spots were found to be over-expressed (red spot) and several were under expressed (green spot) as compared to control (Figs. 4a-c). Three proteins (one was over-expressed and two were under-expressed) of each tissue (liver and urinary bladder) were identified by LC-MS/MS (liquid chromatography-tandem mass spectrometry).DIGE in combination with LC-MS/MS is a powerful tool that may help cancer investigators to understand the molecular mechanisms of cancer progression due to Inorg-As.
 Propose a new researchThese results suggested that selenium (Se) as well as mercury (Hg) may influence the methylation of Inorg-As and this influence could be dependent on the concentration of Se, Hg and/or the sex of the animal. Our study also suggested that the identification and functional assignment of the expressed proteins in the tissues of Inorg-As (III) exposed animals will be useful for understanding and helping to formulate a theory dealing with the molecular events of arsenic toxicity and carcinogenicity.Therefore, it would be very useful if we could do a research study with combination of Inorg-arsenic, Se, and Hg.
 The new research protocol could be the following:For metabolic processing, hamsters provide a good animal model. For carcinogenesis, mouse model is well accepted. The aims of this project are: 1) To map the differential distributions of arsenic (As) metabolites/species in relation to selenium (Se) and mercury (Hg) levels in male and female hamsters and 2) To chart the protein expression profile and identify the defense proteins in mice and hamsters after As injury.
 Experimental hamsters (male or female) will include four groups. The first group will be treated with Na arseniteNa-As(III), the second group with Na-As (III) and Na-selenite (Na-Se (IV)], the third group with Na As (III) and methyl mercuric chloride (MeHgCl), and the final group with Na-As (III), Na-Se (IV), and MeHgci at different levels. Urine and tissue will be collected at different time periods and measured for As species using high performance liquid chromatography/inductively coupled plasma-mass spectrometry (HPLC/ICP-MS). For proteomics, mice (male and female) and hamsters (male and female) will be exposed to Na-As (III)at different levels in tap water, and control mice and hamsters will be given only the tap water. Tissue will be harvested at different time periods. TWO dimensional differential in gel electrophoresis (2D-DIGE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) will be employed to identify the expressed protein.
 In summary, we intend to extend our findings to: 1) Differential distribution of As metabolites in kidney, liver, lung, and urinary bladder of male and female hamsters exposed to Na-As (III), and combined with Na-As (III) and Na-Se (IV) and/or MeHgCl at different levels and different time periods, 2) Show the correlation of As species distribution in the tissue and urine for both male and female hamsters treated with and without Na-Se (IV) and/or MeHgCl, and 3) Show protein expression profile and identify the defense proteins in the tissues (liver, lung, and urinary bladder epithelium) in mice after arsenic injury.
 The significance of this study: The results of which have the following significances: (A) Since Inorg-As is a human carcinogen, understanding how its metabolism is influenced by environmental factors may help understand its toxicity and carcinogenicity, (B) The interactions between arsenic (As), selenium (Se), and mercury (Hg) are of practical significance because populations in various parts of the world are simultaneously exposed to Inorg-As & Se and/or MeHg, (C) These interactions may inhibit the biotransformation of Inorg-As (III) which could increase the amount and toxicity of Inorg-As (III) and MMA (III) in the tissues, (D) Determination of arsenic species profile in the tissues after ingestion of Inorg-As (III), Se (IV), and/or MeHg+ will help understand the tissue specific influence of Se and Hg on Inorg-As (III) metabolism, (E) Correlation of arsenic species between tissue and urine might help to understand the tissue burden of arsenic species when researchers just know the distribution of arsenic species in urine, (F) The identification of the defense proteins (over-expressed and under-expressed) in the tissues of the mouse may lead to understanding the mechanisms of inorganic arsenic injury in human.
 The Superfund Basic Research Program NIEHS Grant Number ES 04940 from the National Institute of Environmental Health Sciences supported this work. Additional support for the mass spectrometry analyses was provided by grants from NIWHS ES 06694, NCI CA 023074 and the BIO5 Institute of the University of Arizona.
 Acknowledge:The Authorwantsto dedicate this paper to the memory of Dr. H. VaskenAposhian and Dr. Mary M. Aposhian who collected urine and bloodsamples from Mexican population. The work was done under Prof. H. V. Aposhian sole supervision and with his great contribution.
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 Sampayo-Reyes, A.; Zakharyan, R. A.; Healy, S. M.; Aposhian, A. V. Monomethylarsonic acid reductase and monomethylarsonou acid in hamster tissue. Chem. Res. Toxicol. 2000, 13, 1181-1186.

Department of Chemistry, Visva Bharati, Santiniketan-731 235 Coordination chemistry plays an important role In fundamental life processes. In living systems metals are strongly bound at the active sites by metallo-enzymes. It is well-known that biochemistry is the coordination chemistry of living systems.  The metal ions occurring in fresh waters and polluted waters are tied up as complexes by the naturally occurring ligands and chelating agents such as humic substances. In fresh water copper(II) is fixed as copper(II) - humic acid complex and thereby rendered non-toxic to the biota. In marine organisms, such as crab, arsenic (III) exists as the non-toxic complex, arsenobetaine and safe for human consumption. On the other hand, the inorganic forms of arsenic(III) are toxic. Elemental mercury is not very toxic but the methyl derivatives are highly toxic and responsible for all fatal cases of mercury poisoning. It is thus important to have an understanding of the chemical species of an element in the environment. This leads as to chemical speciation which is an important aspect of environmental analysis and research. The state  of art of  speciation of some important elements- copper, lead, arsenic and mercury - is critically examined

Purpose. The character and level of the statistical relationship between the content of germanium and “toxic elements” in coal seam c5 of the “Blahodatna” mine and the main features of their distribution were established for the assessment of possible environmental risks during the selective processing of coal enriched with this element. It has been proven that the correlation between germanium and all “toxic” elements is inverse and very weak. The existence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium was revealed. Methods. The research materials included analysis of 38 coal samples for germanium, beryllium, fluorine, mercury and arsenic, performed in accredited state laboratories after 1981. The content of germanium, beryllium and fluorine was determined by quantitative emission spectral analysis, mercury and arsenic – by atomic absorption analysis. The samples were taken during the work of production enterprises and research organizations with the participation of the authors, using the furrow method of sampling in mine workings and from the core of wells from 1981 to 2018. For primary processing of geochemical data, STATISTICA 13.3 and IBM SPSS Statistics 22 were used to calculate basic statistical characteristics, including mean, standard error of the mean, median, kurtosis, mode, standard deviation, variance, minimum and maximum values, coefficient of variation, and sample skewness . Frequency histograms were created for visual assessment of the studied parameters, as well as the characteristics of their distribution were determined. To achieve the objectives of the study, correlation and regression analyzes were carried out using the functions available in Micromine – the leading professional mining and geological information system for 3D modeling, statistical data processing and mining planning. Results. It was established that a general feature of the distribution of ash content, germanium, arsenic, fluorine, mercury and beryllium in the c5 coal seam of the Blahodatna mine field is their non-compliance with normal and lognormal laws and the polymodality of the distributions with a shift of the density nuclei to the left, except for beryllium and germanium. Each of the studied elements in seam c5 of the “Blahodatna” mine accumulated in several forms, which differed significantly in their genesis. At the same time, the forms of finding, which are responsible for the minimum contents, were jointly accumulated at the initial, syngenetic stage. The presence of an inverse and very weak correlation between germanium concentrations and ash content, arsenic, fluorine, and mercury contents in the c5 coal seam of the Blahodatna mine was revealed. The only element considered that forms a very weak positive correlation with germanium is beryllium. Scientific novelty of the results. The presence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the Blahodatna mine was revealed. The polymodality of the distributions was established for all the considered components, while the displacement of the density of their distribution to the left was proved, except for germanium and beryllium. It has been proven that the correlation between germanium and ash content and all “toxic” elements (except beryllium) is inverse and very weak. Practical significance of the results. Justification of the method of the most accurate assessment of the central tendency in the distribution of a sample population of concentrations of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the “Blahodatna” mine. The presence of a very weak correlation between the content of germanium and “toxic” elements makes it possible to predict the minimal nature of possible environmental risks during the selective processing of germanium-enriched coal.

Arsenic, cadmium, lead, and mercury exposures are ubiquitous. These toxic elements have no physiological benefits, engendering interest in minimizing body burden. The physiological process of sweating has long been regarded as “cleansing” and of low risk. Reports of toxicant levels in sweat were sought in Medline, Embase, Toxline, Biosis, and AMED as well as reference lists and grey literature, from inception to March 22, 2011. Of 122 records identified, 24 were included in evidence synthesis. Populations, and sweat collection methods and concentrations varied widely. In individuals with higher exposure or body burden, sweat generally exceeded plasma or urine concentrations, and dermal could match or surpass urinary daily excretion. Arsenic dermal excretion was severalfold higher in arsenic-exposed individuals than in unexposed controls. Cadmium was more concentrated in sweat than in blood plasma. Sweat lead was associated with high-molecular-weight molecules, and in an interventional study, levels were higher with endurance compared with intensive exercise. Mercury levels normalized with repeated saunas in a case report. Sweating deserves consideration for toxic element detoxification. Research including appropriately sized trials is needed to establish safe, effective therapeutic protocols.

In the assortment of pharmaceutical organizations, along with registered medicinal products (MP), there is a fairly large number of biologically active additives (BAA). In connection with the huge growth rate of the number of dietary supplements in the pharmaceutical market, testing their quality, efficacy, safety and the development of new research methods in this area is of particular importance. Objective: to determine the content of inorganic impurities (lead, cadmium, arsenic, mercury) in the selected objects. As a result of studying the assortment of dietary supplements, as well as regulatory documentation, the following objects were selected for the study: Mumie Altai "Balsam of mountains", tablets, manufacturer – LLC "Farm–product", Russia, Barnaul, dietary supplement for food – a source of humic acids, not being a medicine, were obtained through the pharmacy network. Spirulina VEL®, tablets, manufactured by LLC – "V-MIN", Russia, Moscow region, Sergiev Posad, dietary supplement for food – a source of phycocyanins and beta–carotene, not being a medicine, were obtained through the pharmacy network. Materials and methods. For the determination of lead, cadmium and arsenic, the method of atomic absorption spec-trometry was chosen by measuring the absorption of radiation at a certain wavelength corresponding to the element to be determined. To determine mercury, we used an extraction–photometric method based on the formation of a complex compound of mercury (II) –ion with dithizone and measurement of the degree of absorption of non–monochromatic light by the formed complex. Results. The content of lead–ion, cadmium–ion and mercury–ion does not exceed the maximum permissible levels for both samples in accordance with the requirements of both the Technical Regulations and XIV State Pharmacopeia, while the content of arsenic exceeds for the Mumie sample in accordance with the requirements of XIV State Pharmacopeia, but does not exceed according to the requirements of TR CU 021/2011. Conclusion. It was found that the content of heavy metals and arsenic does not exceed the permissible level in accord-ance with the requirements of the Technological Regulations of the Customs Union 021/2011 for both samples. If we compare with the requirements of General Pharmacopoeia Monograph 1.5.3.0009.15 XIV State Pharmacopeia, then there is an excess in the permissible level of arsenic in the Mumie sample.

Abstract The use of arsenic in the preservation of biological specimens was common practice prior to 1970. Because the Naturalis Center for Biodiversity (Naturalis) has extensive collections from before 1950, it was suspected that it held many contaminated specimens. In 2013, Naturalis tested 220 objects for the presence of arsenic over a period of 2 days using a handheld x-ray fluorescence analyzer, which detects arsenic, lead, mercury, and some other metals on objects. This testing provides an estimate of the prevalence of contaminated specimens, as well as a way to determine whether arsenic had spread into noncollection areas. In addition to specimens, floors, desks, keyboards, gloves, elevators, and lab coats were tested for arsenic presence and quantity. The results indicate that mounted specimens do not spread large amounts of arsenic onto the surrounding areas. However, there was sufficient contamination to warrant concern such that the arsenic-handling policy was modified to include different categories of contamination. From this framework, policy and physical changes to the building were made to minimize exposure by collections staff and visitors.

Background: Gold panning has experienced remarkable growth in recent decades in Côte d’Ivoire. This activity contributes substantially to local economies. However, the use of toxic chemicals has an impact on human health and the environment, particularly water resources. The aim of this study was to evaluate the level of contamination of drinking water by metallic trace elements, cyanide and pesticides in an area with high gold panning activity in Côte d'Ivoire. Materials and Methods: Five (5) surface water samples and 5 well water samples were collected in the area of the gold panning sites and then analyzed. The metallic trace elements were measured by atomic absorption spectrometry. Total cyanides were measured according to the NF EN ISO 14403-1 standard and the pesticides were analyzed using a UV-visible HPLC chain. Results:The average concentrations of the metallic trace elements found were 0.125; 0.002; 0.046; 0.036 and 0.009 µg/L respectively for arsenic, Cadmium, Iron, Lead and mercury in surface waters. In the well water, the concentrations of arsenic, cadmium, iron, lead and mercury were respectively 0.025; 0.001; 0.009; 0.007 and 0.002 µg/L. The average concentration of arsenic in all surface water samples and three well water samples was higher than the standard set by WHO (0.01 mg/Kg) for drinking water. Lead and mercury levels in surface water were also higher than recommended standards for drinking water. Cyanide has been found in surface and well waters at relatively low concentrations. Twenty-five pesticides belonging to the chemical families of organochlorines, organophosphates, carbamates and other compounds derived from urea and atrazine were found in the water samples analyzed. Farmer’s well water was qualitatively the most contaminated with the simultaneous presence of several pesticides. The sum of the measured pesticide concentrations for each sample complied with the recommendations for drinking water, set at 0.50 µg/L. Conclusion: Drinking water in this locality is contaminated by metallic trace elements, cyanide and pesticides. The quality of drinking water in this locality must be subject to permanent monitoring in order to protect the health of the population.

Background: Environmental exposures to heavy metals/metalloids such as arsenic, cadmium, and mercury have been implicated in adverse cardiovascular health outcomes. Using data from the All of Us research program, we investigated the associations between these metals/metalloids and six cardiovascular-related biomarkers: systolic blood pressure (SBP), HDL cholesterol, LDL cholesterol, C-reactive protein (CRP), total cholesterol, and triglycerides. Methods: This study explored the relationship between outcome cardiovascular variables (SBP, CRP, LDL, HDL, triglycerides, and total cholesterol) and predictor metal/metalloid variables (cadmium, mercury, and arsenic) among 136 participants (53.4 percent women). We initially conducted linear regression to determine the association between variables of interest. Bayesian Kernel Machine Regression (BKMR) analysis was subsequently performed to capture potential non-linear relationships, as well as interactions among metal/metalloid exposures. In the BKMR analysis, posterior inclusion probabilities (PIPs) quantified the contribution of each metal/metalloid to the outcomes, with higher PIP values indicating a greater likelihood of a specific exposure being a key predictor for a given cardiovascular biomarker. Within the BKMR framework, univariate, bivariate, and overall exposure–response analyses provided insights into the individual and combined effects of metal/metalloid exposures. These analyses identified the factors with the strongest associations and highlighted interactions between exposures. Results: In this study, the average age of male participants was 58.2 years, while female participants had an average age of 55.6 years. The study population included 104 individuals identifying as White (mean age: 57.5 years), 10 as Black or African American (mean age: 63.2 years), 7 as Hispanic (mean age: 48.2), 3 as Asian (mean age: 49.7 years), and 12 as Other race (mean age: 48.8 years). In our study, men exhibited higher levels of SBP, triglycerides, mercury, and arsenic, while women had higher levels of CRP, LDL cholesterol, HDL cholesterol, total cholesterol, and cadmium. Black people exhibited higher levels and greater variability in markers of cardiovascular risk and inflammation (e.g., blood pressure and CRP), Asians consistently showed the lowest levels across most biomarkers, while White people, Hispanics, and the “Other” group demonstrated moderate levels with some variability. In linear regression, we identified significant positive associations between mercury and HDL cholesterol, arsenic and triglycerides, and arsenic and total cholesterol. In BKMR analysis, PIP results revealed that mercury had the highest predictive contribution for SBP, HDL cholesterol, and triglycerides; cadmium for CRP; and arsenic for LDL and total cholesterol. Univariate and bivariate exposure–response analyses in BKMR demonstrated non-linear exposure–response patterns, including U-shaped and inverted U-shaped patterns for cadmium, particularly CRP and total cholesterol. Traditional linear regression techniques would have missed these patterns. Conclusion: Our study results highlight the influence of environmental metal/metalloid exposures on cardiovascular biomarkers, providing evidence of non-linear and interactive effects that warrant further investigation to understand their role in cardiovascular disease risk better.

The metalloid arsenic (As) and the metals lead (Pb) and mercury (Hg), which together we call the “Toxic Triad”, are among the pollutants of greatest global concern, harming the health of millions of people and contributing to biodiversity loss. The widespread distribution of As, Pb and Hg facilitates the exposure of humans and other species to these elements simultaneously, potentially amplifying their individual toxic effects. While As, Pb and Hg are well established as toxic elements, the mechanisms by which they interact with genetic material and impact the health of various species remain incompletely understood. This is particularly true regarding the combined effects of these three elements. In this context, the objective of this work was to perform a toxicogenomic analysis of As, Pb and Hg to highlight multiple aspects of element-gene interactions, in addition to revisiting information on the genotoxicity and carcinogenicity of the Toxic Triad. By using The Comparative Toxicogenomics Database, it was possible to identify that As interacts with 7666 genes across various species, while Pb influences 3525 genes, and Hg affects 692 genes. Removing duplicate gene names, the three elements interact with 9763 genes across multiple species. Considering the top-20 As/Pb/Hg-interacting genes, catalase (CAT), NFE2 like bZIP transcription factor 2 (NFE2L2), caspase 3 (CASP3), heme oxygenase (HMOX1), tumor necrosis factor (TNF), NAD(P)H quinone dehydrogenase 1 (NQO1) and interleukin 6 (IL6) were the most frequently observed. In total, 172 genes have the potential to interact with the three elements. Gene ontology analysis based on those genes evidenced that the Toxic Triad affects several cellular compartments and molecular functions, highlighting its effect on stimulation of toxic stress mechanisms. These 172 genes are also associated with various diseases, especially those of the urogenital tract, as well as being related to biological pathways involved in infectious diseases caused by viruses, bacteria and parasites. Arsenic was the element with the best-substantiated genotoxic and carcinogenic activity. This article details, through a toxicogenomic approach, the genetic bases that underlie the toxic effects of As, Pb and Hg.

Chemical compounds such as arsenic, mercury and organochlorine pesticides have been extensively used as preventive and curative conservation treatments for cultural and biological collections to protect them from pest and mold infestations. Most of the aforementioned compounds have been classified as carcinogenic, mutagenic and teratogenic and represent a health risk for members of staff exposed to contaminated objects. The present study addresses the internal exposure of 28 museum employees in Museum für Naturkunde Berlin by measuring arsenic species and mercury in urine as well as hexachlorocyclohexane isomers (α-HCH, β-HCH, γ-HCH), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (4,4′-DDT) and its main metabolite, dichlorodiphenyldichloroethylene (4,4′-DDE), and pentachlorophenol (PCP) in blood serum. This study was carried out in order to assess the internal exposure of Natural History Museum staff members to toxic metals and organochlorine pesticides. During a working week, two blood samples and five urine samples were taken from each participant, involving 8 women and 20 men. Information about work activity and exposure related factors such as dust development through work, use of personal protective equipment, as well as a nutrition diary were obtained through a questionnaire. Information on fish and seafood intakes as well as amalgam fillings was also available. The results of the study showed that the museum staff members had quantified concentrations of arsenic (median of 6.4 μg/l; maximum of 339 μg/l), mercury (median of 0.20 μg/l; max of 2.6 μg/l), β-HCH (median of 0.12 μg/l; max of 0.39 μg/l) and 4,4′-DDT (median of 0.050 μg/l; max of 0.82 μg/l). Despite that all the concentrations were below the established reference values, multivariate regression models were able to show that museum staff members are currently exposed to the aforementioned compounds while handling museum objects. To validate our findings, further studies are required.

Looking at the global scenario, it has been found that a huge perccntage of population around the globe consider groundwater as their main source for drinking. But unfortunately, this main source is being heavily exposed to various heavy metals like mercury, cadmium, arsenic making it unfit for consumption, ultimately posing threat to human health out there. Although groundwater is considered as safe, but high concentrations of heavy metals like arsenic (As) (above the permissible limit) in ground water can pose risk to human health. Toxicity level of inorganic arsenic is more than the organic one. Arsenic contamination is having a worldwide effect. Arsenic is found to be carcinogcnic in nature, genotoxic as well as cytotoxic. Prolonged exposure to arsenic causes various health hazards like arsenicosis, skin cancer, pigmentation, neurobehavioral effects, impaired intellect and various other chronic illness. Creating awareness and providing proper medical care still remains a big challenge. The biomarkers of arsenic exposure include nails, hair, urine and blood sample. This paper provides an overall overview of ground water arsenic contamination, its health hazards, its toxicity and metabolism in human body. The paper also reviews various analytical techniques that are being used to detect arsenic, the collective steps required to eradicate this global problem and provide high quality safe drinking water for the future generations to come.

Potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs) frequently coexist in soils near industrial areas and sometimes in environmental compartments directly linked to feed (forage) and food (milk) production. However, the distribution of these pollutants along the dairy farm production chain is unclear. Here, we analyzed soil, forage, and milk samples from 16 livestock farms in Spain: several PTEs and PAHs were quantified. Farms were compared in terms of whether they were close to (<5 km) or far away from (>5 km) industrial areas. The results showed that PTEs and PAHs were enriched in the soils and forages from farms close to industrial areas, but not in the milk. In the soil, the maximum concentrations of PTEs reached 141, 46.1, 3.67, 6.11, and 138 mg kg−1 for chromium, arsenic, cadmium, mercury, and lead, respectively, while fluoranthene (172.8 µg kg−1) and benzo(b)fluoranthene (177.4 µg kg−1) were the most abundant PAHs. Principal component analysis of the soil PTEs suggested common pollution sources for iron, arsenic, and lead. In the forage, the maximum contents of chromium, arsenic, cadmium, mercury, and lead were 32.8, 7.87, 1.31, 0.47, and 7.85 mg kg−1, respectively. The PAH found in the highest concentration in the feed forage was pyrene (120 µg kg−1). In the milk, the maximum PTE levels were much lower than in the soil or the feed forages: 74.1, 16.1, 0.12, 0.28, and 2.7 µg kg−1 for chromium, arsenic, cadmium, mercury, and lead, respectively. Neither of the two milk samples exceeded the 20 µg kg−1 limit for lead set in EU 1881/2006. Pyrene was the most abundant PAH found in the milk (39.4 µg kg−1), while high molecular weight PAHs were not detected. For PTEs, the results showed that soil–forage transfer factors were higher than forage–milk ratios. Our results suggest that soils and forages around farms near industries, as well as the milk produced from those farms, have generally low levels of PTE and PAH contaminants.

The impact of contaminated leachate on groundwater from landfills is well known, but the specific effects on bacterial consortia are less well-studied. Bacterial communities in a landfill and an urban site located in Suzhou, China, were studied using Illumina high-throughput sequencing. A total of 153 944 good-quality reads were produced and sequences assigned to 6388 operational taxonomic units. Bacterial consortia consisted of up to 16 phyla, including Proteobacteria (31.9%–94.9% at landfill, 25.1%–43.3% at urban sites), Actinobacteria (0%–28.7% at landfill, 9.9%–34.3% at urban sites), Bacteroidetes (1.4%–25.6% at landfill, 5.6%–7.8% at urban sites), Chloroflexi (0.4%–26.5% at urban sites only), and unclassified bacteria. Pseudomonas was the dominant (67%–93%) genus in landfill leachate. Arsenic concentrations in landfill raw leachate (RL) (1.11 × 103 μg/L) and fresh leachate (FL2) (1.78 × 103 μg/L) and mercury concentrations in RL (10.9 μg/L) and FL2 (7.37 μg/L) exceeded Chinese State Environmental Protection Administration standards for leachate in landfills. The Shannon diversity index and Chao1 richness estimate showed RL and FL2 lacked richness and diversity when compared with other samples. This is consistent with stresses imposed by elevated arsenic and mercury and has implications for ecological site remediation by bioremediation or natural attenuation.

Purpose. To establish the nature and level of the statistical relationship between the concentrations of germanium and "toxic elements" in coal seam c5 of the "Blagodatna" mine and the main features of their distribution to assess possible environmental risks during the selective processing of coal enriched with this element. Methodology. The factual basis of the work was the results of 58 determinations of the spectral emission analysis of germanium, beryllium, fluorine, mercury and arsenic. To calculate basic statistical characteristics, all geochemical data were processed using STATISTICA 13.3 and IBM SPSS Statistics 22 programs.Construction of frequency histograms of germanium concentrations and coal seam thickness was performed, as well as determination of their distribution characteristics. Correlation and regression analyzes were performed using methods available in Micromine, one of the leading professional mining and geological information systems for 3D modeling, statistical data processing and mine planning. Findigs. The existence of an inverse and very weak correlation between the concentrations of germanium and the content of beryllium, fluorine, mercury and arsenic in coal seam c5 of the "Blagodatna" mine was established, which makes it possible to predict the minimal nature of possible environmental risks during the selective processing of germanium-enriched coal. All studied elements accumulated in several forms, which differed significantly in their genesis.Each of the elements that were studied in seam c5 of the "Blagodatna" mine accumulated in several forms, which differed significantly in their genesis. At the same time, the forms of their occurrence, which are responsible for the minimum contents, were jointly accumulated at the syngenetic stage. Scientific novelty. The existence of genetically different forms of germanium, arsenic, fluorine, mercury and beryllium in the coal seam was revealed. For all considered elements, the polymodality of the distributions was established with the same displacement of the distribution density to the left. It has been proven that the correlation between Ge and all "toxic" elements is inverse and very weak. Practical significance. A substantiated method of the most correct assessment of the central tendency of the distribution of a sample population of concentrations of germanium, arsenic, fluorine, mercury and beryllium in coal seam c5 of the "Blagodatna" mine.The presence of a very weak negative correlation between Ge content and toxic elements makes it possible to predict the minimal nature of possible environmental risks during the selective processing of Ge-enriched coal.

In this study, Skin-lightening creams commonly sold in Mbarara municipality were analyzed for chemical parameters (pH, thermal stability and fatty substance content), total hydroquinone, Lead, Mercury, and Arsenic contents. Total heavy metal content was determined by atomic absorption spectrophotometry. The levels of hydroquinone were determined using High Performance liquid chromatography (HPLC). All the creams showed detectable mean levels of mercury, ranging from 0.07±0.01ppm to 0.33±0.01ppm. Only 26.31% of the creams showed detectable levels of lead and 15.79% creams recorded detectable levels of arsenic. The mean levels of hydroquinone ranged from 0.54±0.02% to 4.47±0.02%. All the creams passed the thermal stability and fatty substance content tests. However, all the creams had very low pH values below the recommended 4.5- 8.5 pH ranges by Uganda National Bureau of Standards (UNBS). The levels of mercury, arsenic and lead in the samples were less than the UNBS, European Union and US Food and Drug Administration’s acceptable limits. Only 84.2% of the cream samples analyzed contained hydroquinone levels higher than the recommended WHO limit of 2%. The use of such creams may lead to serious health hazards. While the low concentrations of heavy metals detected in the cream samples analyzed do not pose any potential risk to consumers, repeated application of these creams may cause a cumulative effect over prolonged exposure. The low pH values may cause skin irritations. Therefore, the community needs to be sensitized on the implications of using skin lightening creams and UNBS should conduct periodic analysis to ascertain the levels of hydroquinone, heavy metals, and chemical requirements of skin lightening creams sold in Uganda as well as encourage manufacturers to state the exact bleaching agents in their creams.

Background: The World Health Organization's designation of Corona Virus Disease - 2019 (COVID-19) as a global pandemic in 2020 shocked the world. There is no known treatment for the virus, although the FDA has licensed several vaccines for its prevention; thus, desperation within society has resulted in a growing use of medicinal plant-based therapies, such as Azadirachta indica, Zingiber officinale, Allium sativum, Nigella sativa, and, Vernonia amygdalina among others, that have been claimed to alleviate COVID-19 symptoms. Aim: the study assessed the health risk of some heavy metals associated with the consumption of Z. officinale rhizome in some selected Local Government Areas of Akwa Ibom (Southern Nigeria) and Enugu (Eastern Nigeria) States, where consumption was increased significantly due to COVID-19 pandemic. Method: Atomic absorption spectroscopy was used to quantify the amount of heavy metals in Zingiber officinale following standard digestion procedures. Health Risk Assessment was conducted using Estimated Daily Intake, Target Hazard Quotient, Hazard Index, Carcinogenic Risk as well overall statistical analysis, to ascertain the long-term health potential risk of consuming Zingiber officinale herbal supplements. Result: The mean concentration of arsenic, cadmium, and lead in Z. officinale rhizome ranges from 0.001 to 0.942 mg/kg, 3.403 to 4.386 mg/kg, and 0.002 to 0.244 mg/kg, respectively, while that of mercury, and nickel all locations was 0.001 mg/kg, and 1.377 to 3.100 mg/kg, respectively. Conclusion: All heavy metals but arsenic and mercury were higher in concentration than the prescribed limit, hence possess are potential risks among these locations in the future. The hazard quotient (HQ) values of all heavy metals were <1 in all the samples, thus relatively safe to consume the plant but with caution to checkmate arsenic or mercury poisoning.

Water contamination with heavy metals is increased due to environmental contaminants. Arsenic, cadmium, mercury, and lead are well-known toxic heavy metals for humans. Lactobacillus acidophilus is an ideal absorbent for the removal of metals from drinking water. In this study, the ability of treated and untreated L. acidophilus ATCC 4356 to remove four heavy metals, simultaneously, from multi-metallic contaminated water in 24 h was investigated. In addition, the stability of the bacteria–metal complexes was evaluated in simulated gastrointestinal tract conditions. According to the results, untreated L. acidophilus could remove 99.01% and 92.35% of mercury and lead in water, respectively (initial concentration of 700 µg.L−1; inoculum size of 2.6×1012 CFU.mL−1; pH 4; 37°C; 24 h), whereas removal of arsenic and cadmium, under the same conditions, was 91.28% and 61.91% by heat and NaOH treated cells, respectively. In the digest condition, the complexes of bacteria-metal were reversible and the bond stability of untreated bacteria–Hg complexes was stronger than other complexes. The results suggest that treated or untreated L. acidophilus ATCC 4356 cells have the potential to adsorb heavy metals in contaminated water.

Diabetes Mellitus (DM) is a condition of hyperglycemia due to defects of insulin secretion and/or insulin action. Toxic metals such as lead, nickel, cadmium, arsenic and mercury have been identified which accumulate in various biological samples from T2D (type 2 diabetes) patients through environmental pollution and food chain. Present study will elucidate the toxicological effects of mercury (II) chloride in the pancreatic islets and liver tissues of rat which leads to dysfunction and degeneration of pancreatic islets and liver. Photomicrograph of histology of treated pancreas exhibited the disruption of islets, disorientation of cells and disruption of connective tissue septa. In mercury (II) chloride treated group pancreatic cells were found to be pyknotic and cellular death was confirmed by membrane rupture and necrosis. Alteration of blood glucose levels were observed by glucose tolerance test. The liver sections of rats treated with mercury (II) chloride showed modification in the structure of this organ. Treated liver showed lower periodic acid/Schiff response. In this study, changes in the architecture of pancreatic islets as well as liver may be the reason behind diabetes.

In order to evaluate the safety of selected commercial spices brands, concentration of lead, mercury and arsenic, as well as moisture and mineral contents were analyzed in samples of dried black and white pepper powders, black, white and green peppercorns, black cumin seeds and ginger powder. Lead (Pb), mercury (Hg) and arsenic (As) concentrations in spice samples purchased from local markets in Belgrade were determined, after a microwave digestion of the samples, by atomic absorption spectrometry (AAS), using the graphite furnace AAS technique (Pb), cold vapor AAS technique (Hg) and hydride generation AAS technique (As). Trace levels of Pb, Hg and As in the selected dried spices samples were in the range 0.10 ppm - 0.79 ppm, 0.01 ppm - 0.10 ppm and 0.01 ppm - 0.51 ppm, respectively. The maximum Pb concentration was determined in the sample of ginger and it was 0.79 ppm, the maximum concentration of Hg was 0.10 ppm, determined in green peppercorns samples, while the maximum concentration of As in powdered black pepper sample was 0.51 ppm. The moisture and mineral contents in the different analyzed spices were in the range 1.70-13.10% and 3.40-6.50%, respectively. According to the obtained results, the concentrations of the analyzed toxic elements, as well as the moisture and mineral content in selected spices, were below the maximum permissible limits declared by the national legislations deemed safe for human consumption.

Environmental contamination by heavy metals is a significant global concern due to its adverse impacts on human, animal, and ecosystem health. Heavy metals such as lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As) are particularly worrying because of their persistence in the environment and toxic potential. These metals can be found in water bodies, affecting the quality of drinking water and aquatic ecosystems. Exposure to these metals through water can cause acute and chronic poisoning, damage to kidneys, liver, and nervous system, and increase the risk of cancer. Homeopathic medicines have great potential for treating intoxications and have been demonstrated clinically; however, other medicines still need to be tested. Zebrafish (Danio rerio) is used to study the toxicity of hazardous chemicals, including the assessment of impacts on reproductive, cardiovascular, and neural development, making it a relevant model to explore the efficacy and safety of homeopathic treatments. Studies on arsenate, mercury, and lead intoxication using the aquatic model have shown that homeopathic medicines (Arsenicum album, Mercurius solubilis, and Plumbum metallicum) reduced anxiety as well as physical and neurological effects caused by fish intoxication. The advantages of using Zebrafish as a research model include small size and low maintenance cost, rapid development, high fecundity, and external reproduction, as well as sequenced genome and genetic similarity to humans. This makes Danio rerio a model used worldwide.

The purpose of research is the ecological assessment of the impact of flood sedimentation on arable land of the Oka River floodplain agrolandscape. Research on studying the arrival of pollutants in the flood sediments on arable land floodplain agrolandscape was conducted in 2022-2023 on a stationary observation site of 16 ha, located 2 km from the northeastern administrative boundary of Ryazan Ryazan region (left bank of the central part of the Oka River floodplain near the village of Shumash). Studying sediment load was carried out by sampling sediments with the help of pile plastic mats imitating the top soil cover (mat area 0.14 m2) installed in advance in the control points (before the beginning of spring flooding). During the experiment, the value of sediment load was established, the content of pollutants in flood sediments in comparison with the underlying soil was studied, the degree of contamination of sediments with heavy metals and arsenic was assessed, and the structure of the influx of the studied chemical elements into the agrolandscape with flood sediments was analyzed. Of the pollutants considered, cadmium is more actively concentrated in flood sediments of the stationary observation site, followed by mercury, zinc, nickel, arsenic, manganese, lead, and copper and chromium less actively. The input of gross forms of heavy metals amounted to: copper - 260.5 g/ha; zinc - 1468.0 g/ha, lead - 255.8 g/ha; cadmium - 108.1 g/ha; nickel - 499.2 g/ha; chromium - 508.6 g/kg; mercury - 0.6 g/ha; arsenic - 115.6 g/ha; manganese - 8907.6 g/ha. The arrival of pollutants in the process of sedimentogenesis on the territory of agrolandscape in the floodplain of the Oka River indicates the need to organize and conduct environmental monitoring of the content of heavy metals and arsenic in flood sediments and underlying soil, as well as preventive measures to improve its buffer properties.

The purpose of the research was an environmental assessment of the impact of flood sedimentation on the arable alluvial soil of the floodplain during the spring flood of the river Oka. An experiment to study the supply of heavy metals and arsenic along with flood sediments to arable lands in the flooded part of the river floodplain Oka was carried out in 2023 on an area of 20 hectares located 2 km north of the border of Ryazan. The study of sediment load on the experimental site was carried out using sediment traps installed in advance on the soil surface, located at a distance of 0.45 km from each other. During the experiment, the level of the sediment load was established, the content of pollutants in flood sediments was studied in comparison with the underlying soil, the degree of contamination of sediments with heavy metals and arsenic was assessed and the structure of the flow of the studied chemical elements into the agricultural landscape with flood sediments was analyzed. Of the pollutants considered, cadmium is the most concentrated in flood sediments at the stationary observation site, followed by mercury, zinc, nickel, manganese, lead, and arsenic with a significant lag, and copper and chromium are concentrated less actively. The intake of gross forms of heavy metals was: manganese – 8793.4 g/ha; zinc – 1435.28 g/ha; chromium – 539 g/ha; nickel – 523.6 g/ha; copper – 280.28 g/ha; lead – 238.7 g/ha; cadmium – 112.42 g/ha; arsenic – 87.93 g/ha; mercury – 0.65 g/ha. The revealed tendency of contamination with heavy metals and arsenic in the process of sedimentogenes is on the territory of the floodplain agricultural landscape of the river Oka conditions the need to develop comprehensive preventive and rehabilitation measures that include a selective selection of crops that do not accumulate heavy metals, as well as the use of organomineral ameliorants. At the same time, it is recommended to conduct agroecological monitoring of the studied agricultural landscape based on studying the cycles of migration of heavy metals.

Abstract A simple, automated wet digestion procedure was developed for the quantitative determination by atomic absorption spectroscopy (AAS) of arsenic, cadmium, copper, mercury, lead, selenium, and zinc in animal tissue. A commercial digestion block system with automated temperature programming was used. Recoveries of all elements from spiked bovine liver and kidney samples exceed 95%. The analytical results obtained for samples of NBS Bovine Liver (No. 1577a) agree well with certified values. The procedure is safe and requires minimum analyst time.

The quality of coastal waters in Niger delta have increasingly and adversely impacted by varieties of contaminants occasioned by environmental degradation and aquatic perturbation posed by petroleum exploration activities. This tends to undermine nutritional and health benefits derived from consumption of shellfish harvested from these waters. This study investigated tissue burden, hazard indices and human health risks associated with toxic element contaminants in bivalve shellfish harvested from coastal waters of Niger delta. Four species of bivalve shellfish; bloody cockle (Anadara senilis), donax clam (Donax rugosus), knife clam (Tagelus adansonaii) and mangrove oyster (Crassosstra gasar) collected from four locations were assessed for levels of toxic element contaminants as well as hazard indices and human health risk associated with their consumption. The tissue burden of toxic element contaminants was determined using atomic absorption spectrometer while United State Environmental Protection Agency (US EPA) method was employed to estimate hazard indices and human health risk. Results indicated lead concentrations were within the 1.5mg/kg acceptable limits while levels of cadmium, arsenic and mercury were higher than FAO limits of 0.5, 0, 0.5 mg/kg respectively. The estimated human health risk indicated non-carcinogenic values and hazard indices higher than threshold value of one for cadmium, total arsenic and methyl mercury while values for inorganic arsenic at some locations were higher than stipulated one in one million (1.0x10-6) chances. This implies that toxic elements apart from lead in bivalves shellfish from these locations can induce potential deleterious health effects at consumption of 48g/day of bivalve shellfish.

The biochemical transformation of mercury, tin, arsenic and bismuth through formation of volatile alkylated species performs a fundamental role in determining the environmental processing of these elements. While the toxicity of inorganic forms of most of these compounds are well documented (e.g., arsenic, mercury) and some of them are of relatively low toxicity (e.g., tin, bismuth), the more lipid-soluble organometals can be highly toxic. In the present study we investigated the cyto- and genotoxicity of five volatile metal(loid) compounds: trimethylbismuth, dimethylarsenic iodide, trimethylarsine, tetramethyltin, and dimethylmercury. As far as we know, this is the first study investigating the toxicity of volatile metal(loid) compoundsin vitro. Our results showed that dimethylmercury was most toxic to all three used cell lines (CHO-9 cells, CaCo, Hep-G2) followed by dimethylarsenic iodide. Tetramethyltin was the least toxic compound; however, the toxicity was also dependend upon the cell type. Human colon cells (CaCo) were most susceptible to the toxicity of the volatile compounds compared to the other cell lines. We conclude from our study that volatile metal(loid) compounds can be toxic to mammalian cells already at very low concentrations but the toxicity depends upon the metal(loid) species and the exposed cell type.

Central Russia is traditionally the most important area of crop production and agriculture. The purpose of this study was the ecological and hygienic study of the accumulation of heavy metals and arsenic, as well as biologically active substances in the aboveground part of bitter wormwood (Artemisia absinthium L.), harvested in urbocenoses of Central Russia. Under the conditions of the experiment, more than 50 samples of the aboveground part of bitter wormwood prepared in the territories of the Voronezh region, which are different in terms of anthropogenic impact, from a typical region of central Russia, were analyzed for the content of heavy metals and arsenic, as well as flavonoids, extractive substances and essential oils. The presence of physiological barriers that prevent the accumulation of an excess of a number of toxic elements (lead, cadmium, mercury, arsenic, cobalt, nickel, chromium) in the plant was revealed. The aerial part of the wormwood is bitter with significant accumulated quantities of copper and zinc. The peculiarities of accumulation of heavy metals should be taken into account when planning places for harvesting bitter wormwood and assessing the quality of raw materials. It was revealed that the accumulation of bitter flavonoids and extractive substances extracted with 70% ethyl alcohol in the aerial part of wormwood is slightly influenced by the toxic elements determined; for all heavy metals and arsenic, a negative effect on the content of essential oils was noted.

We have measured fluorine concentration in samples taken from humans, such as sweat, saliva, snivel and tear in addition to hair, nail and urine, together with those of other elements by means of a three-detector measuring system. Fluorine has been known as one of the most toxic elements as well as arsenic, lead, mercury and cadmium which contaminate environment over the wide area. This system allowed us to discuss about fluorine concentration related to other elements'. A standard-free method established by us has been applied to quantitative analyses of these samples. By means of these methods, quantitative analysis becomes possible for samples of less than 1mg or 1μl and it is quite suited to tear, snivel and sweat. As one of the conclusion, sweat, snivel and tear give useful information in addition to the samples which have been traditionally analyzed. It is found that titanium concentration in a body is well estimated by analyses of sweat, snivel and saliva, arsenic concentration can be estimated by sweat analysis in addition to urine analysis, and nickel is well evaluated by sweat and tear. In this way, it is required to estimate elemental concentration in a human body by measuring various clinical samples. Especially, correlation between fluorine and arsenic is found in a few bio-medical samples.

Water pollution caused by mining activity presents significant environmental and public health challenges. Open-pit mining, acid mine drainage (AMD), and heavy metals such as arsenic, mercury, lead, and cadmium threaten local ecosystems and populations. Open-pit mining, acid mine drainage (AMD), and heavy metals such as arsenic, mercury, lead, and cadmium threaten local ecosystems and tribal populations. Hydrogeochemical analysis reveals pH levels of 7.1 to 7.9 and total dissolved solids (TDS) up to 437 mg/L, TDS, turbidity, and SO42− exceeded the Bureau of Indian Standards (BIS) drinking acceptable limits and suggested that water is unsuitable for direct consumption with pollution sources including mining discharge (22.4%) and ash dumping (41.3%). Biotechnological solutions show promise for mitigating mining pollution. Desulfovibrio desulfuricans and Acidithiobacillus ferrooxidans detoxify AMD by neutralizing acidity and removing metals like cadmium and lead. Bacillus cereus combined with biochar efficiently removes arsenic, cadmium, and chromium without harming aquatic life or crops. Systematic water sampling analyzed pH, turbidity, and heavy metals using advanced spectroscopy techniques. Insights from mines highlight microbial diversity in methane wells, dominated by Methanobacteria for hydrogenotrophic methanogenesis, and Roseomonas and Methylobacterium in marginal wells aiding methane utilization. This study aims to identify specific pollutants affecting water quality near mining areas and explore sustainable microbial treatments for detoxification. Evaluating health risks from long-term exposure to toxic metals will address knowledge gaps and guide actionable recommendations for improving water quality, safeguarding public health, and promoting sustainable mining practices in the region.

A hypersaline protected wetland in the UAE was assessed from February to April of 2021 for parameters such as temperature, pH, COD, total dissolved solids, ORP, electrical conductivity, total and E. coli, salinity, turbidity, chloride, ammonia, nitrate, total nitrogen, phosphorus, and heavy metals to assess its current status. Wasit Nature Reserve’s salinity values ranged between 17.1 and 64.78 psu, while D.O values ranged between 6.3 and 8.41 ppm. The values for nitrate were between 50.70 and 57.6 ppm, while the values for chloride were between 12,642.0 and 37,244.0 ppm. Results for heavy metals showed that Iron and Aluminum were the highest concentrations in sediments, with an average of 5599.3 mg/kg and 3171.1 mg/kg, respectively. Mercury and arsenic reported the lowest concentrations, with an average of 0.0 mg/kg and 2.4 mg/kg, respectively. Hazard quotient values were 2239.72 mg/kg for iron, 0 mg/kg for mercury, and 0.05 mg/kg for arsenic, indicating that iron levels are considered hazardous and water-quality indicators concluded high pollution levels. The results indicate that the hypersaline nature of the wetland contributes to the deviation from the permissible limits, as demonstrated by the calculated “poor“water-quality index and “highly polluted” water-pollution index. Due to their ecological relevance, wetlands in the region could serve as indicators of ecological well-being, highlighting the need for regular monitoring and evaluation.

The article presents the results of an ecological and hygienic study of the accumulation of heavy metals and arsenic, as well as biologically active substances in nettles of dioecious leaves harvested in urbanized areas of central Russia, experiencing various anthropogenic impacts. More than 50 samples of nettles of dioecious leaves collected in various territories of the Voronezh region, as a typical region of central Russia, were analyzed for the content of heavy metals and arsenic, as well as the sum of oxycinnamic acids in terms of chlorogenic acid. All test samples were found to meet the requirements of regulatory documentation. Nettles dioecious leaves limitedly accumulate toxic elements such as lead, cadmium, mercury, arsenic, cobalt, nickel, chromium. Nettles dioecious leaves are able to selectively concentrate copper and zinc. The peculiarities of accumulation of toxic elements from nettle soils by dioecious leaves should be taken into account when planning places for harvesting medicinal plant raw materials and assessing its quality. The content of the sum of oxycinnamic acids in samples of nettle leaves collected in some urbocenoses of the Voronezh region is on average 1.5–2 times higher than in samples of natural biocenoses of protected areas. It result of a complex toxic effect on the plant organism, for example, near large roads, industrial enterprises, it is possible to reduce the biosynthesis of hydroxy-cinnamic acids in nettles of dioecious leaves. The calculated values of the correlation coefficients showed that lead, arsenic, nickel, cobalt have a moderate negative effect on the accumulation of oxycinnamic acids.

One of the common problem in fishponds is heavy metal contamination. Though there are some heavy metal elements that are naturally occurring, but due to human activities, their concentration goes beyond what is normal. In this study, health risks analysis using Estimated Daily Intake (EDI), Total Hazard Quotient (THQ), Target Cancer Risk (TCR) were done to assess if the quantities of the heavy metals, such as: Arsenic, Cadmium, Chromium, Lead, and Mercury, impose risks to consumer. Arsenic had the highest concentration among all other heavy metals in crab aligue, having 46.83 mg/kg. The consumption of bangus meat may result in an EDI that is greater than PTDI, especially for Arsenic [15.22731-18.10317 μg kg−1 BW d−1]. Similarly, consuming crab aligue may also result to a high EDI for Arsenic [2.48197-5.27841μg kg−1 BW d−1]. THQ was also evaluated as well as the sum of individual heavy metal values which is the Hazard Index (HI) that exceeded to 1 multiple times. In terms of TCR levels, all of the heavy metals exceeded the acceptable limit for cancer risks. Shapiro-Wilk Test had shown non-normal distribution of data for EDI, THQ, and TCR. Spearman’s Correlation Test, meanwhile, suggested that there is a significant relationship between the quantities of heavy metals in bangus meat and crab aligue as well as EDI, THQ, and TCR. In general, based on the health risks assessments (EDI, THQ, and TCR), Arsenic, an established carcinogen, can be the greatest contributor in developing risks and disease, while the varying concentration of Chromium and Cadmium in the samples may also pose risks to consumers. This implies that strict management measures should be implemented to mitigate or lessen the discharge of these heavy metals in the aquatic systems.

ABSTRACT This study aimed to investigate the levels of heavy metals in surface and groundwater sources within the vicinity of a gold mine in Iran, as well as to evaluate the associated health and carcinogenic risks. A total of 45 water samples were collected from the mine effluent, the downstream of a river receiving the effluent of the mine, and downstream water resources. Subsequent to laboratory digestion of the samples, arsenic levels were determined using atomic fluorescence spectrophotometry, while other heavy metals were quantified using inductively coupled plasma mass spectrometry (ICP-MS). Data analysis was conducted utilizing IBM SPSS software (Version 22). The health risks and carcinogenic potentials associated with arsenic, lead, cadmium, chromium, cobalt, manganese, mercury, nickel, copper, and zinc were assessed for both pediatric and adult populations. The findings revealed that, in most instances, heavy metal concentrations exceeded the recommended standards for drinking water quality. Furthermore, the health and carcinogenic risks posed to both children and adults were found to surpass the maximum acceptable levels.

Increasing soil pollution all over the world has instigated global concerns as enormous quantities of toxic chemicals and heavy metals like cadmium, lead, mercury, petrochemicals, insecticides, polycyclic aromatic hydrocarbons (PAHs) and chlorophenols are finding their way into the environment, affecting the land and soil, causing soil pollution and thus posing a threat and menace to health and well- being of people and ecosystem. The ubiquitous dissemination, low bioavailability, high perseverance of contaminants like poly-hydrocarbon and metals in soil have the potentially destructive effects to human health, envisages to study the biodegradation of PAHs (polycyclic aromatic hydrocarbons) and PACs (polycyclic aromatic compounds). The diversity of micro-organisms that diminish the PAHs/PACs can be utilized in the advancement of bioremediation techniques. The role of metal-tolerant, (PAH)-degrading bacteria helps in the biodegradation of organic compounds at miscellaneous polluted sites. The isolation of (PAHs)-degrading bacteria from contaminated soil samples collected from garages and petrol pumps of Delhi and NCR region was carried out in the present study. Also, the bacterial samples were tested for the tolerance towards 4 heavy metals- arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg). Morphological studies and biochemical tests were conducted to find the genera of the bacterial samples. The study indicates that hydrocarbons were degraded by the isolates P1, P2, P4, P5, P5*, G1, G3. These isolates were also found to be tolerant at a high concentration of metals (Arsenic, Cadmium, Mercury, and Lead) as minimum inhibitory concentration (MIC) was also calculated. Antibiotic susceptibility of the isolates was tested against various antibiotics. Thus the study suggests that the isolates identified as Pseudomonas aeruginosa, Acinetobacter baumanii, and Klebsiella pneumoniae are not only PAH-degrading but metal-tolerant and antibiotic-resistant too and are of immense potential for bioremediation of contaminated soils.

The paper examined the concentrations of heavy metals and microbial parameters in groundwater and were compared to World Health Organisation (WHO)guidelines and National Standard for Drinking Water Quality standard. A total of 800 boreholes and wells water samples were purposefully and systematically collected in the metropolis and subjected to laboratory analysis where mean concentration values of Cadmium, Chromium, Zinc, Iron, Lead, Mercury, Arsenic, Copper, Manganese, Total Coliform count and Escherichia coli were determined in line with APHA 1998 standard procedures. The T- test statistical analysis, p<0.05 results showed that there were high and low significant variations between the concentrations values of heavy metals with WHO and NSDWQ permissible limits especially during wet season while microbial parameters only showed high significant variations except Zinc, Mercury, and Arsenic recorded no significant differences. The study therefore drew inference that wastewater and geomorphic processes contribute significantly to groundwater contaminations in the metropolis and recommends public education and enlightenment, strong legislation, provision of standard water treatment plants, adoption sustainable environmental concepts, attitudinal change, good drainage system should strictly be adhered to in order to harness good drinkable water potentials.

The Chauvai Hg-Sb deposit is a striking example of combining two contrasting types of mineralization in space: mercury-antimony and gold ones. The article studies the spatial-temporal and genetic relationships of goldore and mercury-antimony mineralization based on a complex of both traditional geological and mineralogicalgeochemical methods, as well as modern instrumental methods for analyzing the mineral composition. Two types of ores with clear structural confinedness have been found at the deposit: a) mercury-antimonic (cinnabarantimonite) ores, associated with jasperoid breccias and manifested exclusively along the tectonic contact of limestone of the Alai section and terrigenous rocks of the Tolubai Formation, and b) gold- sulphide (arsenopyritepyritic) ores, localized in slightly modified carbonate-terrigenous rocks of the Tolubai Formation, overlying the plane of tectonic contact. Ore formation occurred during the following stages: in the late diagenetic, without interruption passing into the catagenetic-hydrothermal, characterized by the formation of gold mineralization, and then in the later hydrothermal-telethermal, characterized by the development of Hg-Sb mineralization. It is established that the main carrying agent of invisible gold (“invisible gold”) in ores is framboidal and idiomorphic pyrite and, especially, its high-arsenic varieties. A set of conducted studies has shown that the gold ore and mercury-antimony mineralization is broken in time and is genetically associated with various hydrothermalmetasomatic processes, and the Chauvai deposit can be classified as a Carlin-like type.

In the United States (U.S.), up to 14% of the population depend on private wells as their primary drinking water source. The U.S. government does not regulate contaminants in private wells. The goals of this study were to investigate the quality of drinking water from unregulated private wells within one mile (1.6 kilometers) of an effluent-dominated river in the arid Southwest, determine differences in contaminant levels between wet and dry seasons, and identify contributions from human sources by specifically measuring man-made organic contaminants (perfluorooctanoic acid (PFOA), perfluorooctane sulfate (PFOS), and sucralose). Samples were collected during two dry seasons and two wet seasons over the course of two years and analyzed for microbial (Escherichia coli), inorganic (arsenic, cadmium, chromium, copper, lead, mercury, nitrate), and synthetic organic (PFOA, PFOS, and sucralose) contaminants. Arsenic, nitrate, and Escherichia coli concentrations exceeded their respective regulatory levels of 0.01 mg/L, 10 mg/L, and 1 colony forming unit (CFU)/100 mL, respectively. The measured concentrations of PFOA and PFOS exceeded the respective Public Health Advisory level. Arsenic, PFOA, PFOS, and sucralose were significantly higher during the dry seasons, whereas E. coli was higher during the wet seasons. While some contaminants were correlated (e.g., As and Hg ρ = 0.87; PFOA and PFOS ρ = 0.45), the lack of correlation between different contaminant types indicates that they may arise from different sources. Multi-faceted interventions are needed to reduce exposure to drinking water above health-based guidelines.

Определено содержание тяжелых металлов: ртути, кадмия, железа, свинца и мышьяка в различных частях плодовых тел ксилотрофных грибов: Pholiota squarrosa , Kuehneromyces mutabilis , Flammulina velutipes , Pleurotus pulmonarius . Содержание тяжелых металлов определяли методом абсорбционной спектроскопии до и после экстракции водой на атомно-абсорбционном спектрометре с электротермическим распылением. Большинство исследованных грибов не соответствуют требованиям санитарных правил по содержанию мышьяка и кадмия. Содержание свинца оказалось высоким только в P. pulmonarius и шляпках K. mutabilis . Кроме того, K. mutabilis содержит большое количество ртути. Во всех исследованных грибах преобладают железо и свинец, мышьяка больше у K. mutabilis , P. pulmonarius и F. velutipes , кадмия больше у P. squarrosa . Плодовые тела K. mutabilis содержат больше тяжелых металлов. Плодовые тела F. velutipes содержат меньше тяжелых металлов, за исключением кадмия. Элементы, по-видимому, поступают из древесного субстрата, накапливаются в мицелии и потом попадают в плодовые тела. В большинстве случаев в шляпках тяжелых металлов больше, чем в ножках, что объясняется сходством транспорта контаминантов с транспортом необходимых элементов в шляпки. Способность элементов извлекаться водой из плодовых тел грибов зависит от элемента и от части плодового тела. Ртуть плохо извлекается горячей водой из плодовых тел грибов. Свинец не извлекается водой из F. velutipes , но хорошо извлекается из других грибов. Кадмий не извлекается из шляпок К. mutabilis и ножек Р. squarrosa ; железо и мышьяк хорошо извлекаются. The content of heavy metals: mercury, cadmium, iron, lead and arsenic was determined: in various parts of xylotrophic mushrooms fruit bodies: Pholiota squarrosa , Kuehneromyces mutabilis , Flammulina velutipes , Pleurotus pulmonarius . The content of heavy metals was determined by absorption spectroscopy before and after extraction with water an atomic absorption spectrometer with electrothermal atomization. Most of the studied mushrooms do not meet the requirements of sanitary rules for the content of arsenic and cadmium. The lead content was found to be high only in the P. pulmonarius and caps of K. mutabilis . Also, K. mutabilis is high in mercury. Iron and lead predominate in all studied mushrooms, arsenic is higher in K. mutabilis and F. velutipes , and cadmium is higher in P. squarrosa . Thefruit bodies of K. mutabilis contain more heavy metals. The fruit bodies ofF. velutipes contain less heavy metals except for cadmium. Elements, apparently, come from the wood substrate, accumulate in the mycelium and then enter the fruiting bodies. In most cases, there are more heavy metals in the caps than in the stems, which is explained by the similarity of the transport of contaminants with the transport of the necessary elements into the caps. The ability of elements to be extracted by water from the fruiting bodies of mushrooms depends on the element and on the fruiting body part. Mercury is poorly extracted with hot water from the fruiting bodies of mushrooms. Lead is not extracted by water from F. velutipes, but is well extracted from other mushrooms. Cadmium is not extracted from the caps ofK. mutabilis and the stems of P. squarrosa; iron and arsenic are generally well extracted.

The paper addresses the study of the chemical composition of paste used in 26 fragments of sphero-conical vessels from the CC dig of the Bolgar settlement. Complex analytical studies, including optical and electron microscopy, mass spectrometry and emission spectral analysis, were carried out to identify the possible functional purpose of the vessels, as well as to identify potential raw material sources. Areas in the vicinity of the Bolgar settlement were identified, where the composition of the clay is similar to the composition of the ceramic paste. The peculiarity of “mercury — arsenic” ratio in the ceramic clay allowed to make an assumption about their original alchemical nature.

AbstractThree media (sediment, surface water, and dragonfly larvae tissue) were collected from wetlands surrounding an industrial effluent treatment facility prior to closure. Samples were analyzed for metals, total mercury, and polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) concentrations. Sediment and surface water concentrations were compared to provincial and federal guidelines, as well as reference wetland concentrations. Exceedances of arsenic, cadmium, chromium, copper, zinc, and PCDD/PCDF guidelines were found in deeper areas of wetlands historically contaminated from effluent, as well as wetlands exposed to current effluent inputs. Composite Libellulidae samples were collected from wetlands, and comparisons were made to reference tissue concentrations + 20%. Elevated As, Cu and Pb tissue concentrations were measured at two site wetlands, but total mercury (THg) and PCDD/PCDF reference tissue concentrations were higher than wetlands near the effluent treatment facility. Spearman rho tests identified a significant correlation between sediment and tissue Pb concentrations and between surface water and sediment THg concentrations. Results suggest relatively low ecological risk to macroinvertebrates within wetlands near the effluent treatment facility from current effluent inputs, and highlight strengths and weaknesses of federal and provincial guidelines.

A growing body of research has begun to link exposure to environmental contaminants, such as heavy metals, with a variety of negative health outcomes. In this paper, we sought to review the current research describing the impact of certain common contaminant metals on cardiovascular (CV) health. We reviewed ten metals: lead, barium, nickel, chromium, cadmium, arsenic, mercury, selenium, zinc, and copper. After a literature review, we briefly summarized the routes of environmental exposure, pathophysiological mechanisms, CV health impacts, and exposure prevention and/or mitigation strategies for each metal. The resulting article discloses a broad spectrum of pathological significance, from relatively benign substances with little to no described effects on CV health, such as chromium and selenium, to substances with a wide-ranging and relatively severe spectrum of CV pathologies, such as arsenic, cadmium, and lead. It is our hope that this article will provide clinicians with a practical overview of the impact of these common environmental contaminants on CV health as well as highlight areas that require further investigation to better understand how these metals impact the incidence and progression of CV diseases.