Vanadium: a review of the reproductive and developmental toxicity

Prosthetic Metals: Release, Metabolism and Toxicity

The development of metallic joint prostheses has been ongoing for more than a century alongside advancements in hip and knee arthroplasty. Among the materials utilized, the Cobalt-Chromium-Molybdenum (Co-Cr-Mo) and Titanium-Aluminum-Vanadium (Ti-Al-V) alloys are predominant in joint prosthesis construction, predominantly due to their commendable biocompatibility, mechanical strength, and corrosion resistance. Nonetheless, over time, the physical wear, electrochemical corrosion, and inflammation induced by these alloys that occur post-implantation can cause the release of various metallic components. The released metals can then flow and metabolize in vivo, subsequently causing potential local or systemic harm. This review first details joint prosthesis development and acknowledges the release of prosthetic metals. Second, we outline the metallic concentration, biodistribution, and elimination pathways of the released prosthetic metals. Lastly, we discuss the possible organ, cellular, critical biomolecules, and significant signaling pathway toxicities and adverse effects that arise from exposure to these metals.

Testicular protective effects of hesperidin against chemical and biological toxicants

Toxic agents can adversely impact the male reproductive system mainly via activating oxidative stress affecting the seminiferous epithelia, spermatogenesis, sperms, and the testis. Toxic agents lead to the excessive generation of reactive oxygen species (ROS), such as hydroxyl radicals, hydrogen peroxide, and superoxide anions. ROS exert a cytotoxic effect and oxidative damage to nucleic acids, proteins, and membrane lipids. Hesperidin is a pharmacologically active phytoflavone abundantly occurring in citrus fruits, such as oranges and lemons. It has shown various pharmacological properties such as antioxidant, anti-inflammatory, anti-carcinogenic, analgesic, antiviral, anti-coagulant, hypolipidemic, and hypoglycemic effects. Hesperidin has been found to exert protective effects against natural and chemical toxins-induced organ toxicity. Considerable evidence has implicated the testicular protective effects of hesperidin against the toxicological properties of pharmaceutical drugs as well as biological and chemical agents, and in the present review, we discussed, for the first time, the reported studies. The resultant data indicate that hesperidin can exert testicular protective effects through antioxidant properties.

Evaluation of immunotoxicity of sodium metavanadate following drinking water exposure in female B6C3F1/N mice in a 28-day study

Sodium metavanadate (NaVO3 ) is a pentavalent vanadium compound used in the metal industry and dietary supplements; human exposure occurs through inhalation of fumes and dust and ingestion of NaVO3 -containing products. The objective of this study was to assess the potential immunotoxicity of NaVO3 . Female B6C3F1/N mice were exposed to 0-500 ppm NaVO3 in drinking water for 28 days and evaluated for effects on immune cell populations and innate, cellular-mediated, and humoral-mediated immunity. There was a decreasing trend in body weight (BW) and BW gain in NaVO3 exposed mice, with a decrease (p ≤ 0.05) in BW gain at ≥250 ppm, relative to control. Conversely, increasing trends in spleen weights and an increase (p ≤ 0.05) in the spleen:BW ratio at ≥250 ppm NaVO3 were observed. NaVO3 exposure altered antibody production against sheep red blood cells (SRBC). Antibody forming cells (AFC)/106 spleen cells exhibited a decreasing trend, with a decrease (p ≤ 0.05) at 500 ppm NaVO3 , concurrent with an increase in percent B cells. NaVO3 had no effect on the serum anti-SRBC IgM antibody titers or anti-keyhole limpet hemocyanin antibody production. Exposure to NaVO3 decreased the percentage of natural killer cells at all dose levels (p ≤ 0.05), with no effect on the lytic activity. NaVO3 altered T-cell populations at 500 ppm but had no effect on T-cell proliferative responses or the lytic activity of cytotoxic T cells. Collectively, these data indicate that NaVO3 exposure can adversely affect the immune system by inducing alterations in humoral-mediated immunity, specifically the AFC response, with no effect on cell-mediated or innate immunity.

Exposure of Reproductive-Aged Women to Multiple Metals and Its Associations with Unexplained Recurrent Miscarriage

Exposure to heavy metals exerts toxic effects on female reproduction and embryo development. This study examined the exposure of patients with unexplained recurrent miscarriage (uRM) to multiple metals and the correlations among exposures to different metals. A total of 275 participants were enrolled, including 43 healthy women without previous miscarriage (the control group) and 232 uRM women (the case group); among these uRM women, 159 had two miscarriages (2M), 42 had three miscarriages (3M) and 31 had four or more miscarriages (≥4M). A total of 22 elements were measured in serum samples via inductively coupled plasma-mass spectrometry. The levels of calcium (104.37 mg/L vs. 92.65/93.02/92.61/92.47 mg/L) and selenium (131.85 µg/L vs. 117.80/118.04/115.88/124.35 µg/L) were higher in the controls than in the total uRM group and the 2M, 3M and ≥4M subgroups. The level of vanadium was significantly lower in the controls than in the total uRM group (0.15 µg/L vs. 0.23 µg/L), and the level of lead was lower in the controls than that in the total uRM group and the 2M, 3M and ≥4M subgroups (0.01 µg/L vs. 0.28/0.18/0.63/0.34 µg/L). After adjusting for age, body mass index and education level, calcium and selenium exposure were consistently negatively associated with miscarriage, while lead exposure was positively associated with miscarriage. In addition, the correlations among exposures to different metals slightly differed between the control and uRM groups. Therefore, changes in some metal elements in the blood might be related to the risk of uRM.

In Vitro, Oral Acute, and Repeated 28-Day Oral Dose Toxicity of a Mixed-Valence Polyoxovanadate Cluster

Polyoxovanadates (POV) are a subgroup of polyoxometalates (POM), which are nanosized clusters with reported biological activities. This manuscript describes the first toxicity evaluation of a mixed-valence polyoxovanadate, pentadecavanadate, (Me4N)6[V15O36Cl], abbreviated as V15. Cytotoxicity experiments using peripheral blood mononuclear cells (PBMC), larvae of Artemia salina Leach, and in vivo oral acute and repeated 28-day doses in mice was carried out. The LC50 values in PBMC cells and A. salina were 17.5 ± 5.8 μmol L-1, and 17.9 µg L-1, respectively, which indicates high cytotoxic activity. The toxicity in mice was not observed upon acute exposure in a single dose, however, the V15 repeated 28-day oral administration demonstrated high toxicity using 25 mg/kg, 50 mg/kg and, 300 mg/kg doses. The biochemical and hematological analyses during the 28-day administration of V15 showed significant alteration of the metabolic parameters related to the kidney and liver, suggesting moderate toxicity. The V15 toxicity was attributed to the oxidative stress and lipid peroxidation, once thiobarbituric acid (TBAR) levels significantly increased in both males and females treated with high doses of the POV and also in males treated with a lower dose of the POV. This is the first study reporting a treatment-related mortality in animals acutely administrated with a mixed-valence POV, contrasting with the well-known, less toxic decavanadate. These results document the toxicity of this mixed-valence POV, which may not be suitable for biomedical applications.

Leaching of metals from red mud and toxicity in human cells in vitro

Toxicity of red mud, a waste from alumina production, was studied using human breast cancer MCF-7 cells. Culture medium was prepared by mixing water for 3 days with the red mud and removing solid particles afterwards (red mud water). Culture for 48 h of the cells in this medium in neutral pH decreased the cell viability, as analyzed by the MTT-test, and increased the formation of reactive oxygen species. Thus, neutralization does not eliminate the toxicity of red mud. In preliminary experiments, a combined effect of five metals (Cr, Li, V, Al, As) increased the formation of ROS (reactive oxygen species) statistically significantly. Each element separately did not have a similar effect. In environmental applications, red mud is likely to be used after activation. In this work, the red mud was activated using hydrochloric acid to study the physical and chemical properties before and after the treatment. Activation increased the specific surface area of red mud from 16 m2 g-1 to 148 m2 g-1, which is beneficial in many environmental applications such as in the adsorptive removal of pollutants. After activation, leaching of some elements from the red mud decreased (e.g. Al from 38.0 to 0.56 mg L-1, As from 21.0 to 2.1 μg L-1, V from 172.0 to 29.8 μg L-1) while some increased (e.g. Li from 0.04 to 2.81 mg L-1, Cr from 0.35 to 3.23 mg L-1).

Mobility and bioaccessibility of arsenic (As) bound to titanium dioxide (TiO2) water treatment residuals (WTRs)

This work systematically describes arsenic mobility and potential bioaccessibility of arsenic-enriched titanium dioxide water treatment residuals (TiO₂ WTRs) by employing a suite of wet chemical experiments and spectroscopic measurements. Specifically, Environmental Protection Agency (EPA) digestion method 3051a indicated <3% of total arsenic in the solid phase was released, and arsenic assessed by EPA method 1340 for bioaccessibility was below detection limits. A novel finding is while the arsenic appeared to be stable under highly acidic digestion conditions, it is in fact highly mobile when exposed to simple phosphate solutions. On average, 55% of arsenic was extracted from all samples during a 50-day replenishment study. This was equivalent to 169 mg kg^-1 arsenic released from the solid phase. Macroscopic desorption experiments indicated arsenic likely formed inner-sphere bonds with the TiO₂ particles present in the samples. This was confirmed with X-ray absorption spectroscopy (XAS), where an interatomic distance of 3.32 Å and a coordination number (CN) of 1.79 titanium atoms were determined. This translates to a configuration of arsenic on TiO₂ surfaces as a bidentate binuclear inner-sphere complex. Thus, both macroscopic and spectroscopic data are in agreement. During incubation experiments, arsenic(V) was actively reduced to arsenic(III); the amount of arsenic(III) in solution varied from 8 to 38% of total dissolved arsenic. Lastly, elevated concentrations and mobility of vanadium in these systems merit further investigation. The high mobility of arsenic and its potential for reduction when reintroduced into the environment, particularly in agriculturally important areas, presents an important risk when waste products are not properly managed.

Major, minor and trace element concentrations in the muscle and liver of a pregnant female Pacific sharpnose shark (Rhizoprionodon longurio) and its embryos

The Pacific sharpnose shark Rhizoprionodon longurio is an abundant shark consumed by human population in Mexico. This study aimed to determine and compare the concentrations of thirteen essential elements (K, S, P, Na, Ca, Mg, Fe, Zn, Se, Cu, Mn, Cr and Co) and eleven non-essential elements (As, Sr, Cd, V, Li, U, Tl, Ag, Sn, Sb and Pb) in the muscle and liver of a pregnant female, fished near the copper mine of Santa Rosalía, and their respective embryos. Major, minor and trace (essential and non-essential) elements were transferred during gestation to embryos. All major elements analyzed had significantly higher concentrations in embryos liver than the pregnant female, except for magnesium. Higher concentrations in embryo tissues than the pregnant female tissues were found for the non-essential trace elements of strontium, lithium, thallium and silver, which indicate an easy maternal transfer of these non-essential elements.

Consequences of the exposome to gestational diabetes mellitus

The exposome is the cumulative measure of environmental influences and associated biological responses throughout the lifespan, including those from the environment, diet, behaviour, and endogenous processes. The exposome concept and the 2030 Agenda for the Sustainable Development Goals (SDGs) from the United Nations are the basis for understanding the aetiology and consequences of non-communicable diseases, including gestational diabetes mellitus (GDM). Pregnancy may be developed in an environment with adverse factors part of the immediate internal medium for fetus development and the external medium to which the pregnant woman is exposed. The placenta is the interface between maternal and fetal compartments and acts as a protective barrier or easing agent to transfer exposome from mother to fetus. Under and over-nutrition in utero, exposure to adverse environmental pollutants such as heavy metals, endocrine-disrupting chemicals, pesticides, drugs, pharmaceuticals, lifestyle, air pollutants, and tobacco smoke plays a determinant role in the development of GDM. This phenomenon is worsened by metabolic stress postnatally, such as obesity which increases the risk of GDM and other diseases. Clinical risk factors for GDM development include its aetiology. It is proposed that knowledge-based interventions to change the potential interdependent ecto-exposome and endo-exposome could avoid the occurrence and consequences of GDM.

Mechanical Properties of Ti-Nb-Cu Alloys for Dental Machining Applications

Titanium has excellent biocompatibility and good corrosion resistance and is extensively used in dental implants and denture bases. However, pure titanium lacks the strength for use in dental prostheses that require relatively high strength. We developed 15 different types of Ti-Nb-Cu alloys and investigated their alloy phases and mechanical properties, including tensile and yield strength, elongation after fracture, and Vickers hardness. The alloy phases of Ti-8%Nb-2%Cu and Ti-13%Nb-2%Cu were α + β, while those of Ti-5%Nb-5%Cu and Ti-10%Nb-5%Cu were α + Ti₂Cu. The tensile strength and hardness of these alloys were significantly higher than those of titanium; however, their elongation was less. In particular, the yield strength of these alloys was more than twice that of titanium. These differences in mechanical properties are attributable to solid-solution strengthening and precipitation strengthening. Other compositions with an alloy phase of α + β + Ti₂Cu or β + Ti₂Cu had high hardness but not high strength. These results suggest that the Ti-8%Nb-2%Cu, Ti-5%Nb-5%Cu, Ti-13%Nb-2%Cu, and Ti-10%Nb-5%Cu alloys can be applied to dental prostheses, which are subject to very high forces from accessories such as long-span bridges, clasps, implant-retained superstructures, and narrow-diameter implants.

Vanadium pentoxide induced oxidative stress and cellular senescence in human lung fibroblasts

Both environmental exposure to vanadium pentoxide (V2O5, V+5 for its ionic counterparts) and fibroblast senescence are associated with pulmonary fibrosis, but whether V+5 causes fibroblast senescence remains unknown. We found in a dose-response study that 2-40 μM V+5 caused human lung fibroblasts (HLF) senescence with increased senescence-associated β-galactosidase activity and p16 expression, while cell death occurred at higher concentration (LC50, 82 μM V+5). Notably, measures of reactive oxygen species (ROS) production with fluorescence probes showed no association of ROS with V+5-dependent senescence. Preloading catalase (polyethylene-conjugated), a H2O2 scavenger, did not alleviate the cellular senescence induced by V+5. Analyses of the cellular glutathione (GSH) system showed that V+5 oxidized GSH, increased GSH biosynthesis, stimulated cellular GSH efflux and increased protein S-glutathionylation, and addition of N-acetyl cysteine inhibited V+5-elevated p16 expression, suggesting that thiol oxidation mediates V+5-caused senescence. Moreover, strong correlations between GSSG/GSH redox potential (Eh), protein S-glutathionylation, and cellular senescence (R2 > 0.99, p < 0.05) were present in V+5-treated cells. Studies with cell-free and enzyme-free solutions showed that V+5 directly oxidized GSH with formation of V+4 and GSSG in the absence of O2. Analyses of V+5 and V+4 in HLF and culture media showed that V+5 was reduced to V+4 in cells and that a stable V+4/V+5 ratio was rapidly achieved in extracellular media, indicating ongoing release of V+4 and reoxidation to V+5. Together, the results show that V+5-dependent fibroblast senescence is associated with a cellular/extracellular redox cycling mechanism involving the GSH system and occurring under conditions that do not cause cell death. These results establish a mechanism by which environmental vanadium from food, dietary supplements or drinking water, can cause or contribute to lung fibrosis in the absence of high-level occupational exposures and cytotoxic cell death.

Effect of Ultrasonic Surface Mechanical Attrition Treatment-Induced Nanograins on the Mechanical Properties and Biocompatibility of Pure Titanium

Commercially pure titanium (Ti) is widely used in bio-implants due to its high corrosion resistance. However, Ti exhibits marginally low mechanical and tribological properties, which limit its applications in some orthopedic implants. In this work, the Ti samples were subjected to ultrasonic surface mechanical attrition treatment (SMAT) for various durations to improve their surface properties such as hardness, strength and surface energy. SMAT-induced grain refinement was analyzed using optical, scanning electron and atomic force microscopy techniques. A Vickers hardness test was performed to determine the through-thickness hardness. Mechanical testing was carried out to measure the yield strength, ultimate tensile strength and ductility of the specimens. Corrosion tests were performed on a Gamry Potentiostat. The surface energy of SMAT-modified samples was calculated using the Owens–Wendt method. It was observed that SMAT reduced the average grain size from 50 μm to as low as 100 nm. The grain refinement and the corresponding grain boundary density led to a significant improvement in mechanical properties and biocompatibility in terms of increased hardness, yield and tensile strengths, surface energy, corrosion rate and hydrophilicity.

Vanadium(IV) oxide affects embryonic development in mice

Vanadium(V) and vanadium(IV) are the predominant redox forms present in the environment, and epidemiological studies have reported that prenatal vanadium exposure is associated with restricted fetal growth and adverse birth outcomes. However, data about the toxic effects of vanadium(IV) oxide (V₂ O₄ ) on the development of mammals are still limited. Therefore, in this work, 4.7, 9.4, or 18.7 mg/kg body weight/injection/day V₂ O₄ was administered through an intraperitoneal (ip) injection to pregnant mice from gestational days 6 to 16. The results showed that V₂ O₄ produced maternal and embryo-fetal toxicity and external abnormalities in the offspring, such as malrotated and malpositioned hind limbs, hematomas and head injuries. Moreover, the skeletons of the fetuses presented reduced ossification of the cranial bones, including the frontal and parietal bones, corresponding to head injuries observed in the external assessment of the fetuses. These results demonstrate that administration of V₂ O₄ to pregnant females in the organogenesis period adversely affects embryonic development.

What to Expect When Expecting in Lab: A Review of Unique Risks and Resources for Pregnant Researchers in the Chemical Laboratory

Pregnancy presents a unique risk to chemical researchers due to their occupational exposures to chemical, equipment, and physical hazards in chemical research laboratories across science, engineering, and technology disciplines. Understanding “risk” as a function of hazard, exposure, and vulnerability, this review aims to critically examine the state of the science for the risks and associated recommendations (or lack thereof) for pregnant researchers in chemical laboratories (labs). Commonly encountered hazards for pregnant lab workers include chemical hazards (organic solvents, heavy metals, engineered nanomaterials, and endocrine disruptors), radiation hazards (ionizing radiation producing equipment and materials and nonionizing radiation producing equipment), and other hazards related to the lab environment (excessive noise, excessive heat, psychosocial stress, strenuous physical work, and/or abnormal working hours). Lab relevant doses and routes of exposure in the chemical lab environment along with literature and governmental recommendations or resources for exposure mitigation are critically assessed. The specific windows of vulnerability based on stage of pregnancy are described for each hazard, if available. Finally, policy gaps for further scientific research are detailed to enhance future guidance to protect pregnant lab workers.

Ion release behavior of vanadium-doped mesoporous bioactive glass particles and the effect of the released ions on osteogenic differentiation of BMSCs via the FAK/MAPK signaling pathway

Vanadium is an important trace element in bone and is involved in bone metabolism, bone formation, and bone growth, but the roles of various vanadium ions, especially of pentavalent vanadium, in bone tissue regenerative repair have been underestimated and even misinterpreted for a long time. The main purposes of this study are to investigate the release profile of Si, Ca, P, and V ions from vanadium doped mesoporous bioactive glass (V-MBG) particles and to explore the effect of pentavalent vanadium ions on proliferation and osteogenic differentiation of BMSCs as well as the corresponding osteogenic signaling pathway. On the basis of preparations of V-MBG particles with different pentavalent vanadium contents, the ion release behavior from V-MBG in distilled water and simulated body fluid was systemically investigated. Furthermore, the cytocompatibility and osteogenic effect of V-MBG extracts were studied in rBMSCs, and the related molecular mechanisms were preliminarily discussed. The results of dissolution experiments showed that the V ionic concentration exhibited a burst increase and then a sustained slow increase in the two media. The resultant V ions from 1.0V-MBG, 4.0V-MBG and 10.0V-MBG at 21 days were about 1.1, 5.8, and 12.5 mg L^-1 in water, respectively, and 1.6, 4.8 and 12.8 mg L^-1 in SBF, respectively. The release behaviors of Si, Ca, P, and V ions were evidently affected by high contents of incorporated vanadium. The cellular results indicated that compared to the control and MBG groups, the V(V) ions in V-MBG extracts at about 19.4 μM markedly promoted the proliferation, the gene and protein expression of BMP-2 and COL-I, and the ALP activity of rBMSCs in non-osteoinductive media, but insignificantly stimulated the OCN protein synthesis. More deeply, V(V) ions at about 19.4 μM significantly upregulated the gene and protein expressions of Itga 2b, FAK, and pERK1/2, demonstrating that V(V) ions could regulate osteogenic differentiation of rBMSCs through the activation of the Itga 2b-FAK-MAPK (pERK1/2) signaling pathway. The in vivo results further confirmed that V-MBG induced and promoted new bone formation in the defect area compared to the PGC and PGC/V-M0 groups. These results would contribute to modify the perception about the biocompatibility and osteogenic promotion of pentavalent vanadium at an appropriate concentration.

Environmental Hazards of Boron and Vanadium Nanoparticles in the Terrestrial Ecosystem-A Case Study with Enchytraeus crypticus

From the start of the 21st century, nanoecotoxicological research has been growing in fast steps due to the need to evaluate the safety of the increasing use of engineered nanomaterials. Boron (B) and vanadium (V) nanoparticles (NPs) generated by anthropogenic activities are subsequently released in the environment; therefore, organisms can be continuously exposed to these NPs for short or long periods. However, the short and long-term effects of BNPs and VNPs on soil organisms are unknown. This work aimed to recognize and describe their potential toxicological effects on the model species Enchytraeus crypticus, assessing survival and reproduction, through a longer-term exposure (56 days (d)-OECD test extension of 28 d), and avoidance behavior, through a short-term exposure (48 hours (h)). After 28 d, BNPs did not induce a significant effect on E. crypticus survival, whereas they decreased the organisms' reproduction at 500 mg/kg. From 10 to 500 mg/kg, VNPs decreased the E. crypticus survival and/or reproduction. After 56 d, 100 to 500 mg/kg BNPs and 50 to 500 mg/kg VNPs, decreased the reproduction output of E. crypticus. The estimated Effect Concentrations (EC_x) based on reproduction, for BNPs, were lower at 56 d compared with 28 d; for VNPs, an opposite pattern was found: EC_x 28 d < EC_x 56 d. BNPs did not induce an avoidance behavior, but organisms avoided the soil contaminated with 10 mg VNPs/kg. The tested NPs showed different E. crypticus apical effects at 28 d from the ones detected at 56 d, dependent on the type of NPs (B vs. V). In general, VNPs showed to be more toxic than BNPs. However, the effects of VNPs were alleviated during the time of exposure, contrarily to BNPs (which became more toxic with extended duration). The present study adds important information about NPs toxicity with ecological significance (at the population level). Including long-term effects, the obtained results contributes to the improvement of NPs risk assessment.

Ameliorative effects of the aqueous extract of Khaya anthotheca (Welw.) C.DC (Meliaceae) in vanadium induced anxiety, memory loss and pathologies in the brain and ovary of mice

ETHNOPHARMACOLOGICAL RELEVANCE

Ethnobotanical enquiries have revealed that Khaya anthotheca (Welw.) C.DC (Meliaceae) has anxiolytic properties and is used to alleviate vaginal dryness in postmenopausal women in Cameroon. The aim of this study was to evaluate the ameliorative effects of the aqueous extract of K. anthotheca in vanadium induced anxiety, memory loss and pathologies in the brain and ovary of mice.

MATERIAL AND METHODS

Forty neonatal female mice were used in this study. All animals received vanadium (3 mg/kg BW/72 h, by lactation and i.p.) for 20 weeks except the Control group. At 16 weeks old, mice were divided into 5 groups (n = 8): Control group received distilled water; V-group received vanadium (V) (3 mg/kg BW every 72 h i.p.), V + Vit E group received vitamin E (500 mg/kg BW/72 h) and vanadium (V) (3 mg/kg BW/72 h i.p, simultaneously). V + KA 125 and V + KA 250 groups received K. anthotheca extract at the doses of 125 and 250 mg/kg BW/day respectively and vanadium (V) (3 mg/kg BW/72 h i.p, simultaneously).The treatment was done per os at 10 mL/kg of volume of administration for 4 weeks. To evalute anxiolytic effects and spatial working memory improved by the extract in mice, the elevated open space test and Y maze test were used respectively. After sacrifice, brains were harvested and pathologies were assessed using cresyl violet stainning and immunohistochemistry (GFAP, Iba-1 and MBP), while pathologies in the ovaries were assessed using immunohistochemistry (Collagen type 1) and H&E stainning.

RESULTS

Results in the three sessions of elevated open space test showed that vanadium exposure resulted in a significant (p < 0.05; p < 0.01) increase of the latency of first entry in the slopes and a significant (p < 0.05; p < 0.01; p < 0.001) decrease of the time spent and number of entries in the slopes however, Khaya anthotheca treatment induced a significant (p < 0.05; p < 0.01) decrease of the latency of first entry in the slopes and a significant (p < 0.05; p < 0.01) increase of the time spent and number of entries in the slopes. In the Y maze test, vanadium exposure resulted in a significant decrease (p < 0.01) in the percentage of correct alternation, K. anthotheca extract at the dose of 250 mg/kg BW however induced a significant (p < 0.05) increase of this percentage of correct spontaneous alternation. In the brain, degeneration induced by vanadium exposure was marked by an increase of GFAP-immunoreactive cells, microgliosis and demyelination. The treatment with Khaya anthotheca extract at the dose of 250 mg/kg BW resulted in the preservation of cellular integrity in the same anatomical regions with reduced astroglial and microglial activation and prevented demyelination. In addition, vanadium exposure decreased Collagen type 1 expression in the ovaries and induced a deterioration of tertiary follicle. Khaya anthotheca treatment at the dose of 250 mg/kg BW induced an increase of expression of Collagen type 1 and alleviated deterioration of the microarchitecture of tertiary follicle induced by vanadium.

CONCLUSION

These effects induced by K. anthotheca extract could justify the traditional use of this plant in Cameroonian traditional medicine to manage anxiety. Therefore, to minimise vanadium induced toxicity, the plant should be given more emphasis as a candidate in developing a modern phytodrug.

Associations of prenatal exposure to vanadium with early-childhood growth: A prospective prenatal cohort study

Prenatal vanadium exposure is reported to be associated with restricted fetal growth and adverse birth outcomes. However, trimester-specific vanadium exposure in relation to early-childhood growth still remains unclear. A total of 1873 Chinese mother-infant pairs from whom a complete series of maternal urinary samples were collected over three stages of pregnancy were included from 2014 to 2016. The urinary concentrations of vanadium were analyzed. Children's anthropometric parameters were measured at birth, 6, 12 and 24 months. In boys, each doubling increase in vanadium concentrations at middle pregnancy was inversely associated with weight-for-length [- 9.07% (-17.21%, -0.93%)] and BMI z-score [- 9.66% (-18.05%, -1.28%)] at 24 months. Moreover, vanadium exposure at late pregnancy was negatively associated with weight [- 9.85% (-16.42%, -3.28%)], weight-for-length [- 11.00% (-18.40%, -3.60%)], and BMI z-scores [- 11.05% (-18.67%, -3.42%)] at 24 months in boys. However, the negative associations were not observed in girls, and we found evidence for sex difference (FDR p for interaction=0.01, 0.01 and 0.03 for weight, weight-for-length and BMI z-scores, respectively). Prenatal vanadium exposure may have an adverse effect on early-childhood growth, and the middle and late pregnancy could be windows of vulnerability for the adverse effects of vanadium exposure on growth development.

VV Reduction by Polaromonas spp. in Vanadium Mine Tailings

Vanadium (V) is an important metal with critical industrial and medical applications. Elevated V contamination, however, can be a threat to the environment and human health. Microorganisms can reduce the more toxic and mobile V^V to the less toxic and immobile V^IV, which could be a detoxification and energy metabolism strategy adopted by V-reducing bacteria (VRB). The limited understanding of microbial responses to V contamination and the mechanisms for V^V reduction, however, hamper our capability to attenuate V contamination. This study focused on determining the microbial responses to elevated V concentration and the mechanisms of V^V reduction in V tailings. The bacterial communities were characterized and compared between the V tailings and the less contaminated adjacent mineral soils. Further, V^V-reducing enrichments indicated that bacteria associated with Polaromonas, a genus belonging to the family Burkholderiaceae, were potentially responsible for V^V reduction. Retrieved metagenome-assembled genomes (MAGs) suggested that the Polaromonas spp. encoded genes (cymA, omcA, and narG) were responsible for V^V reduction. Additionally, Polaromonas spp. was metabolically versatile and could use both organic and inorganic electron donors. The metabolic versatility of Polaromonas spp. may be important for its ability to flourish in the V tailings.

Biochemical and ultrastructural changes in kidney and liver of African Giant Rats (Cricetomysgambianus, Waterhouse, 1840) exposed to intraperitoneal sodium metavanadate (vanadium) intoxication

We studied the hepatic and renal impact of sodium metavanadate (SMV) exposure in African giant rats (AGR). Twelve male AGR were used and divided into two groups. The control group received sterile water while the SMV-exposed group received 3 mg/kg SMV intraperitoneally for 14 days. SMV exposed AGR groups showed significantly decreased activities of serum AST, ALT, ALP and creatinine concentration but increased blood urea nitrogen (BUN), albumin and globulin concentrations. Kidney ultrastructure examination revealed atrophy of the glomerular tuft, loss of podocytes, distortions of the endothelium and glomerular basement membrane. The liver sinusoids fenestration phenotypes were abnormal. Hepatocytes exhibited hypertrophy with uneven, crenated and dentate nuclei. SMV exposure induced activation of monocytes, as well as Kupffer and fibrous cells. Alterations in glomerular podocytes and cell-cell and cell matrix contact and inflammatory liver fibrosis are key events in progressive glomerular failure and hepatic damage due to SMV intoxication.

Vanadium sustainability in the context of innovative recycling and sourcing development

This paper addresses the sustainability of vanadium, taking into account the current state-of-the-art related to primary and secondary sources, substitution, production, and market developments. Vanadium plays a critical role in several strategic industrial applications including steel production and probable widespread utilization in next-generation batteries. Confirming the importance of vanadium, the European Commission identified and formally registered this metal on the 2017 list of Critical Raw Materials for the European Union. The United States and Canada have also addressed the importance of this metal. Like the European economy, the American and Canadian economies rely on vanadium and are not globally independent. This recognized importance of vanadium is driving many efforts in academia and industry to develop technologies for the utilization of secondary vanadium resources using hydrometallurgical and pyrometallurgical techniques. In this paper, current efforts and their outcomes are summarized along with the most recent patents for vanadium recovery.

Heat treatment dependent cytotoxicity of silicalite-1 films deposited on Ti-6Al-4V alloy evaluated by bone-derived cells

A silicalite-1 film (SF) deposited on Ti-6Al-4V alloy was investigated in this study as a promising coating for metallic implants. Two forms of SFs were prepared: as-synthesized SFs (SF-RT), and SFs heated up to 500 °C (SF-500) to remove the excess of template species from the SF surface. The SFs were characterized in detail by X-ray photoelectron spectroscopy (XPS), by Fourier transform infrared spectroscopy (FTIR), by scanning electron microscopy (SEM) and water contact angle measurements (WCA). Two types of bone-derived cells (hFOB 1.19 non-tumor fetal osteoblast cell line and U-2 OS osteosarcoma cell line) were used for a biocompatibility assessment. The initial adhesion of hFOB 1.19 cells, evaluated by cell numbers and cell spreading area, was better supported by SF-500 than by SF-RT. While no increase in cell membrane damage, in ROS generation and in TNF-alpha secretion of bone-derived cells grown on both SFs was found, gamma H2AX staining revealed an elevated DNA damage response of U-2 OS cells grown on heat-treated samples (SF-500). This study also discusses differences between osteosarcoma cell lines and non-tumor osteoblastic cells, stressing the importance of choosing the right cell type model.

Exposure of earthworm (Eisenia fetida) to bauxite residue: Implications for future rehabilitation programmes

Bauxite residue is typically alkaline, has high sodium content and elevated concentrations of trace elements. Effective rehabilitation strategies are needed to mitigate potential environmental risks from its disposal and storage. Increasingly, the importance of viable soil faunal populations as well as establishment of vegetation covers is recognized as key components of successful rehabilitation. Inoculation with earthworms is a strategy for accelerating mine site rehabilitation, but little is known on the effects of bauxite residue properties on earthworm survival and viability. In the current study, earthworms (Eisenia fetida) were exposed for 28 days to a series of bauxite residue/soil treatments (0, 10, 25, 35, 50, 75 and 100% residue) to evaluate possible toxic effects on earthworms, investigate the bioavailability of relevant elements (e.g. As, Cr, V), and assess the risk of element transfer. Results showed that soil containing ≥25% residue (pH ≥ 9.8; ESP ≥ 18.5%; extractable Na ≥ 1122 mg/kg) significantly impacted survival (mortality ≥28%) and reproduction (cocoon production inhibition ≥76%) of the exposed earthworms. Alkalinity, sodicity and bioavailable Na were identified as major factors causing toxicity and some earthworms were observed to adopt compensative response (i.e. swollen body) to cope with osmotic stress. Conversely, soil containing 10% residue (pH = 9.1; ESP = 9.2%; extractable Na = 472 mg/kg) did not elicit significant toxicity at the organism level, but biomarker analysis (i.e. superoxide dismutase and catalase) in earthworm coelomocytes showed an oxidative stress. Furthermore, earthworms exposed to soil containing ≥10% residue took up and accumulated elevated concentrations of Al, As, Cr and V in comparison to the control earthworms. We concluded that earthworm inoculation could be used in future rehabilitation programmes once the key parameters responsible for toxicity are lowered below specific target values (i.e. pH = 9.1, ESP = 18.5%, extractable Na = 1122 mg/kg for Eisenia fetida). Nonetheless, trace element uptake in earthworms should be regularly monitored and the risk to the food chain further investigated.

The Sealing Step in Aluminum Anodizing: A Focus on Sustainable Strategies for Enhancing Both Energy Efficiency and Corrosion Resistance

Increasing demands for environmental accountability and energy efficiency in industrial practice necessitates significant modification(s) of existing technologies and development of new ones to meet the stringent sustainability demands of the future. Generally, development of required new technologies and appropriate modifications of existing ones need to be premised on in-depth appreciation of existing technologies, their limitations, and desired ideal products or processes. In the light of these, published literature mostly in the past 30 years on the sealing process; the second highest energy consuming step in aluminum anodization and a step with significant environmental impacts has been critical reviewed in this systematic review. Emphasis have been placed on the need to reduce both the energy input in the anodization process and environmental implications. The implications of the nano-porous structure of the anodic oxide on mass transport and chemical reactivity of relevant species during the sealing process is highlighted with a focus on exploiting these peculiarities, in improving the quality of sealed products. In addition, perspective is provided on plausible approaches and important factors to be considered in developing sealing procedures that can minimize the energy input and environmental impact of the sealing step, and ensure a more sustainable aluminum anodization process/industry.

Protective Effects of Dietary Antioxidants against Vanadium-Induced Toxicity: A Review

Vanadium (V) in its inorganic forms is a toxic metal and a potent environmental and occupational pollutant and has been reported to induce toxic effects in animals and people. In vivo and in vitro data show that high levels of reactive oxygen species are often implicated in vanadium deleterious effects. Since many dietary (exogenous) antioxidants are known to upregulate the intrinsic antioxidant system and ameliorate oxidative stress-related disorders, this review evaluates their effectiveness in the treatment of vanadium-induced toxicity. Collected data, mostly from animal studies, suggest that dietary antioxidants including ascorbic acid, vitamin E, polyphenols, phytosterols, and extracts from medicinal plants can bring a beneficial effect in vanadium toxicity. These findings show potential preventive effects of dietary antioxidants on vanadium-induced oxidative stress, DNA damage, neurotoxicity, testicular toxicity, and kidney damage. The relevant mechanistic insights of these events are discussed. In summary, the results of studies on the role of dietary antioxidants in vanadium toxicology appear encouraging enough to merit further investigations.

Response of vanadium bioaccumulation in tissues of Mugil cephalus (Linnaeus 1758)

Vanadium accumulation levels in different tissues (muscle and organs) of the striped mullet Mugil cephalus (Linnaeus, 1758) and possible relationships with blood parameters were evaluated in a Natural Protected Area (Lake Faro, Sicily, Italy), during the winter of 2017. Hematological parameters (red blood cell, RBC; white blood cell, WBC; hemoglobin concentration, Hb; hematocrit, Hct; mean corpuscular volume, MCV; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; thrombocytes, TC), biometric indices (weight, total and fork length), and vanadium levels in muscles and organs (gills, liver, stomach and intestine) were determined. Statistical analyses showed significant differences in concentrations of vanadium of the analyzed tissue of M. cephalus and a positive relationship between vanadium concentration in the liver and some hematological parameters (RBC, Hb and Hct) and biometric indices. Our results underline the importance of fish blood parameters as sensitive indicators of toxic impact of environmental factors such as metals. This study, focusing on an ongoing topic, represents a valuable contribution to research concerning the monitoring and prevention of vanadium pollution in aquatic organisms and environments.

Electrochemical property and corrosion behavior of multi-directionally forged titanium in fluoride solution

Multi-directional forging (MDFing) can improve the various properties of metals and alloys due to the evolution of an ultrafine-grained structure. In the present study, electrochemical properties and corrosion behaviors in a fluoride solution of MDFed pure titanium (MDF-Ti) were evaluated by comparing with conventional coarse-grained pure titanium (Ti). The E_open value of MDF-Ti was significantly higher than that of Ti. However, similar potentiodynamic polarization profiles were obtained for Ti and MDF-Ti. Immersion in NaF solution caused no severe corrosion to Ti or MDF-Ti. However, immersion in acidulate phosphate fluoride solution (APF) revealed that MDF-Ti had better corrosion resistance than Ti at shorter time immersion periods and was more susceptible to corrosion for longer immersion. Significantly less release of titanium was observed for MDF-Ti in shorter immersion periods in APF. In conclusion, MDF-Ti showed similar electrochemical behaviors to Ti and less susceptible to corrosion in shorter time APF immersion.

Vanadium-basidiomycete fungi interaction and its impact on vanadium biogeochemistry

Fungi are well known to strongly interact with metals, thereby influencing metal biogeochemistry in the terrestrial environment. To assess and quantify potential fungi-vanadium (V) interactions, Amanita muscaria, Armillaria cepistipes, Xerocomus badius and Bjerkandera adusta were cultured in media containing soluble V (VOSO₄ or NaVO₃) or solid-phase V of different chemical forms and oxidation state (V₂O₃, VO₂, V₂O₅, or V-Ti magnetite slag). All fungi underwent physiological and structural changes, as revealed by alterations in FT-IR peak positions and intensities relative to the control, and morphological changes of mycelia, as observed by scanning electron microscopy. The diametric growth size generally decreased with decreasing oxidation state of V and with increasing concentrations of VOSO₄ and NaVO₃, implying that V toxicity is dependent on V speciation. The tolerance index, the ratio of treated and control mycelium (dry weight), shows different tendencies, suggesting additional factors influencing fungi weight, such as the formation of extrahyphal crystals. Vanadium accumulation from VOSO₄ and NaVO₃ medium in all fungi (up to 51.3 mg g^-1) shows the potential of fungi to immobilise soluble V, thereby reducing its impacts on environmental and human health. Uptake and accumulation of V in slag was insignificant, reflecting the association of slag V with insoluble crystalline materials. The fungal accumulation of V in medium amended with V-oxides demonstrates the ability of fungi to solubilise solid-phase V compounds, thereby introducing previously immobile V into the V biogeochemical cycle and into the food chain where it may impact ecological and human health. A.muscaria lowered the pH of the medium substantially during cultivation, indicating acidolysis and complexolysis via excretion of organic acids (e.g. oxalic acid). Oxidation of VOSO₄ was observed by a colour change of the medium to yellow during B. adusta cultivation, revealing the role of fungally-mediated redox transformation in V (im)mobilisation. The calculated removal efficiencies of soluble V were 40-90% for A. cepistipes and X. badius, but a much lower recovery (0-20%) was observed from V oxides and slag (0-20%) by all fungi. This suggests the probable application of fungi for bio-remediation of mobile/soluble V in contaminated soils but not of V incorporated in the lattice of soil minerals.

Investigation of Possible Leaching Control Mechanisms for Chromium and Vanadium in Electric Arc Furnace (EAF) Slags Using Combined Experimental and Modeling Approaches

In this study, possible leaching control mechanisms for Cr and V in electric arc furnace slags were investigated by using a multi-methodological approach. Aside from chemical and mineralogical bulk analyses, special emphasis was given to surface investigations of the slags prior to and after leaching. In addition, pH dependence leaching tests were performed and the obtained data were evaluated with hydrogeochemical models. Investigations revealed that Cr and V are mainly bound in spinel and wuestite as well as minor amounts of olivine. Spinel and wuestite do not dissolve during water leaching for 48 h, whereas, depending on the composition of olivine, this phase either dissolves and releases V and Cr congruently, or does not dissolve but may hydrate. Melilite may also hydrate, but neither V nor Cr were detected in this phase. It appears that leached V is subsequently adsorbed onto these newly hydrated phases. The combination of the applied methods further showed that the abundance of calcium silicates, spinel, and wuestite is influenced by the FeO/SiO2 and CaO/SiO2 ratio in the slag. Therefore, it is assumed that the leaching of V and Cr can be minimized by changing these ratios to favor the formation of Fe bearing calcium silicate and spinel instead of wuestite.

Field-Enhanced Nanoconvection Accelerated Electrocatalytic Conversion of Water Contaminants and Electricity Generation

The development of high-performance electrocatalytic systems for the extraction of energy from contaminants in wastewater are urgently needed in emerging renewable energy technologies. However, given that most of the contaminants are present in low concentrations, the heterogeneous catalytic reactions often suffer from slow kinetics due to mass transfer limitations. Here, we report that localized free convection induced by enthalpy change of the reaction can enhance interfacial mass transport. This phenomenon can be found around high-curvature nanosized tips. The finite-element numerical simulation shows that the heat of reactions can produce temperature gradients and subsequently lead to fluid motion at the interfaces, which facilitates the rate-limiting step (mass transfer). To demonstrate the effects of localized field-enhanced mass transport in electrocatalytic conversion of aqueous dilute species, a galvanic cell is constructed with a vertically aligned polyaniline array with sharp tips (as cathode) for the detoxification of a low concentration of carcinogenic chromate and synchronous electricity generation, which show lower overpotential (0.17 V decreased), higher reaction rate (increased by 28%), and power density (22.3 W m^-2 in 2 mM chromate). The power output can be scaled up (open voltage of ∼3.7 V and volumetric power density of 840.1 W m^-3) by using a continuous flow-through cell with stacked electrodes for further improve the mass transport.

Osteotoxicity of 3-methylcholanthrene in fish

Many chemicals produced by human activities end up in the aquatic ecosystem causing adverse developmental and reproductive effects in aquatic organisms. There is evidence that some anthropogenic chemicals disturb bone formation and skeletal development but the lack of suitable in vitro and in vivo systems for testing has hindered the identification of underlying mechanisms of osteotoxicity. Several fish systems - an in vitro cell system to study extracellular matrix mineralization and in vivo systems to evaluate bone formation and skeletogenesis - were combined to collect data on the osteotoxic activity of 3-methylcholanthrene (3-MC), a polycyclic aromatic hydrocarbon. Anti-mineralogenic effects, increased incidence of skeletal deformities and reduced bone formation and regeneration were observed in zebrafish upon exposure to 3-MC. Pathway reporter array revealed the role of the aryl hydrocarbon receptor 2 (Ahr2) in the mechanisms underlying 3-MC osteotoxicity in mineralogenic cell lines. Analysis of gene expression in zebrafish larvae confirmed the role of Ahr2 in the signaling of 3-MC toxicity. It also indicated a possible complementary action of the pregnane X receptor (Pxr) in the regulation of genes involved in bone cell activity and differentiation but also in xenobiotic metabolism. Data reported here demonstrated the osteotoxicity of 3-MC but also confirmed the suitability of fish systems to gain insights into the toxic mechanisms of compounds affecting skeletal and bone formation.

Effects of trimester-specific exposure to vanadium on ultrasound measures of fetal growth and birth size: a longitudinal prospective prenatal cohort study

BACKGROUND

Identification of windows of heightened vulnerability to environmental factors has substantial public health implications. Prenatal exposure to vanadium has been linked to adverse birth outcomes; however, critical windows for such exposure during fetal growth remain unknown. We aimed to assess trimester-specific associations of vanadium exposure with ultrasound measures of fetal growth and birth size in a Chinese longitudinal cohort.

METHODS

The present study was embedded in our ongoing prospective prenatal cohort study at the Wuhan Women and Children Medical Care Center (Wuhan, Hubei, China). Pregnant women were eligible for inclusion if they provided signed informed consent and were less than 16 weeks pregnant with a single gestation, and agreed to take in-person interviews, undergo ultrasound examinations, and provide blood and urine samples. We collected urine samples and measured urinary vanadium concentrations using inductively coupled plasma mass spectrometry. We calculated SD scores for ultrasound-measured biparietal diameter, head circumference, occipitofrontal diameter, abdominal circumference, femur length, and estimated fetal weight at 16, 24, and 31 weeks of gestation. We applied linear regressions with generalised estimating equations to estimate associations of urinary vanadium concentrations in each trimester with ultrasound-measured fetal growth parameters or neonatal size at birth.

FINDINGS

As of Oct 12, 2016, we recruited 3075 women who were non-smokers and non-drinkers during pregnancy, provided up to three urine samples during the first, second, and third trimesters, and gave birth to live singletons without birth defects. We excluded women who did not provide information on ultrasound measurements (n=20) or who only had one ultrasound measurement of fetal crown-rump length at the first trimester (n=14). We excluded another 16 women because they had missing values for confounding variables, leaving 3025 women retained in the study. Every doubling of urinary vanadium concentration in the first trimester was associated with a significant increase in femur length (adjusted percentage change 6·4%, 95% CI 0·7 to 12·1) at 16 weeks of gestation and reductions in biparietal diameter (-4·2%, -8·2 to -0·1), head circumference (-6·0%, -10·1 to -1·9), occipitofrontal diameter (-5·7%, -9·9 to -1·5), and abdominal circumference (-5·3%, -9·4 to -1·2) at 31 weeks of gestation. Every doubling of urinary vanadium concentration in the second trimester was significantly associated with reductions in SD scores for head circumference (-7·2%, -14·1 to -0·3) and abdominal circumference (-6·9%, -13·8 to -0·1) at 31 weeks of gestation. The highest quartile of urinary vanadium concentration (>1·18 μg/L) in the first trimester, when compared with the lowest quartile (≤0·60 μg/L), was associated with a mean decrease in birthweight of 12·6 g (95% CI 2·5-22·8; p_trend=0·0055) and a mean decrease in ponderal index of 0·07 kg/m³ (0·01-0·12; p_trend=0·0053). Moreover, newborns with restricted birth size had higher vanadium exposure in the first and third trimesters.

INTERPRETATION

Vanadium might be toxic to humans and impair fetal growth. The first, early second, and late third trimesters could be critical windows for heightened vulnerability to vanadium for fetal growth. Our findings require further investigation in other populations.

FUNDING

National Key R&D Plan of China, National Natural Science Foundation of China, and Fundamental Research Funds for the Central Universities, Huazhong University of Science and Technology.

Vanadium stimulates pepper plant growth and flowering, increases concentrations of amino acids, sugars and chlorophylls, and modifies nutrient concentrations

Vanadium (V) can be absorbed by plants and regulate their growth and development, although contrasting effects have been reported among species and handling conditions. The objective of this work was to evaluate the beneficial effect of V on pepper plants (Capsicum annuum L.). The plants were grown in a hydroponic system with the application of four V concentrations (0, 5, 10, and 15 μM NH₄VO₃). Four weeks after the beginning of the treatments, growth, flowering, biomass, chlorophyll concentration, total amino acids, total soluble sugars, and nutrients were determined in leaves, stems, and roots. The application of 5 μM V increased plant growth, induced floral bud development, and accelerated flowering. The chlorophyll concentration varied according to the type of plant part analyzed. The concentrations of amino acids and sugars in leaves and roots were higher with 5 μM. With 10 and 15 μM V, the plants were smaller and showed toxicity symptoms. The K concentration in leaves decreased as the V dose increased (0 to 15 μM). However, 5 μM V increased the concentrations of N, P, K, Ca, Mg, Cu, Mn, and B, exclusively in stems. The application of 15 μM V decreased the concentrations of Mg and Mn in leaves, but increased those of P, Ca, Mg, Cu, and B in roots. We conclude that V has positive effects on pepper growth and development, as well as on the concentrations of amino acids and total sugars. V was antagonistic with K, Mg, and Mn in leaves, while in stems and roots, there was synergism with macro and micronutrients. Vanadium is a beneficial element with the potential to be used in biostimulation approaches of crops like pepper.

Sodium metavanadate induced cognitive decline, behavioral impairments, oxidative stress and down regulation of myelin basic protein in mice hippocampus: Ameliorative roles of β-spinasterol, and stigmasterol

INTRODUCTION

Exposures to toxic levels of vanadium and soluble vanadium compounds cause behavioral impairments and neurodegeneration via free radical production. Consequently, natural antioxidant sources have been explored for effective and cheap remedy following toxicity. Grewia carpinifolia has been shown to improve behavioral impairments in vanadium-induced neurotoxicity, however, the active compounds implicated remains unknown. Therefore, this study was conducted to investigate ameliorative effects of bioactive compounds from G. carpinifolia on memory and behavioral impairments in vanadium-induced neurotoxicity.

METHODS

Sixty BALB/c mice were equally divided into five groups (A-E). A (control); administered distilled water, B (standard); administered α-tocopherol (500 mg/kg) every 72 hr orally with daily dose of sodium metavanadate (3 mg/kg) intraperitoneally, test groups C, and D; received single oral dose of 100 μg β-spinasterol or stigmasterol (bioactive compounds from G. carpinifolia), respectively, along with sodium metavanadate and the model group E, received sodium metavanadate only for seven consecutive days. Memory, locomotion and muscular strength were accessed using Morris water maze, Open field and hanging wire tests. In vivo antioxidant and neuroprotective activities were evaluated by measuring catalase, superoxide dismutase, MDA, H₂ O₂ , and myelin basic protein (MBP) expression in the hippocampus.

RESULTS

In Morris water maze, stigmasterol significantly (p ≤ 0.05) decreased escape latency and increased swimming time in target quadrant (28.01 ± 0.02; 98.24 ± 17.38 s), respectively, better than α-tocopherol (52.43 ± 13.25; 80.32 ± 15.21) and β-spinasterol (42.09 ± 14.27; 70.91 ± 19.24) in sodium metavanadate-induced memory loss (112.31 ± 9.35; 42.35 ± 11.05). β-Spinasterol and stigmasterol significantly increased exploration and latency in open field and hanging wire tests respectively. Stigmasterol also increased activities of antioxidant enzymes, decreased oxidative stress markers and lipid peroxidation in mice hippocampal homogenates, and increased MBP expression.

CONCLUSIONS

The findings of this study indicate a potential for stigmasterol, a bioactive compound from G. carpinifolia in improving cognitive decline, motor coordination, and ameliorating oxidative stress in vanadium-induced neurotoxicity.

Fabrication of porous covalent organic frameworks as selective and advanced adsorbents for the on-line preconcentration of trace elements against the complex sample matrix

Herein, for the first time, the typical porous Covalent Organic Frameworks (COFs) CTpBD with superior chemical stability and large surface area were applied as sorbents for solid phase extraction of trace ions via flow injection followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. The well-prepared and fully-characterized CTpBD COFs were filled in solid phase extraction cartridge as novel and robust adsorbents for element analysis. Separation and enrichment of Cr (III), Mn (II), Co (II), Ni (II), Cd (II), V (V), Cu (II), As (III), Se (IV), and Mo (VI) was then carried out, and the contents were measured by ICP-MS. Owing to the large surface area and instinctive porous structure of CTpBD, preconcentration of the target trace elements via COF-filled on-line SPE column has achieved low detection limits of 2.1-21.6ngL^-1 along with a wide linearity range at 0.05-25μgL^-1 for all target ions. The relative standard deviations (RSD) of 1.2%-4.3% obtained via 11 parallel determinations at the sample concentration of 100ngL^-1 revealed excellent repeatability of the developed methods Our proposed methods have been successfully utilized for trace element analysis in environmental and food samples.

A novel resource utilization of the calcium-based semi-dry flue gas desulfurization ash: As a reductant to remove chromium and vanadium from vanadium industrial wastewater

A novel resource utilization of the calcium-based semi-dry flue gas desulfurization ash is investigated. In the present study, the semi-dry desulfurization ash is used as a reductant for chromium and vanadium removal by chemical reduction precipitation, the byproduct gypsum and chromium-contained sludge are obtained. Besides, the effects of main operational parameters (reaction pH, desulfurization ash dosage and reaction time) on the heavy metal removal are investigated, and the main reaction mechanism for this treatment technology is also proposed. Under the optimal conditions, the residual concentrations of Cr(VI), total Cr and V are 0.163mg/L, 0.395mg/L and 0.155mg/L, respectively. Additionally, byproduct gypsum and chromium-contained sludge are characterized using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscope-energy dispersive spectrometer (SEM-EDS) and thermogravimetry differential scanning calorimetry (TG-DSC), respectively. Finally, the resource utilization methods of the byproduct gypsum and chromium-contained sludge from this technology are also submitted. The byproduct gypsum can be utilized to produce hemihydrate calcium sulfate whisker, and the roasted heavy metal precipitation can be used as a primary chromium raw material (Cr₂O₃ content is about 83%).

Carbon-dot-based dual-emission silica nanoparticles as a ratiometric fluorescent probe for vanadium(V) detection in mineral water samples

Herein, we propose a simple and effective strategy for designing a ratiometric fluorescent nanosensor. We designed and developed a carbon dots (CDs) based dual-emission nanosensor for vanadium(V) by coating the surface of dye-doped silica nanoparticles with CDs. The fluorescence of dual-emission silica nanoparticles was quenched in acetic acid through potassium bromate (KBrO₃) oxidation. V(V) could catalyze KBrO₃ oxidation reaction process, resulting in the ratiometric fluorescence quenching of dual-emission silica nanoparticles. We investigated several important parameters affecting the performance of the nanosensor. Under the optimized conditions, the detection limit of this nanosensor reached 1.1ngmL^-1 and the linear range from 10 to 800ngmL^-1. Furthermore, we found that the sensor was suitable for determination of V(V) in different mineral water samples with satisfactory results.

Association of adverse birth outcomes with prenatal exposure to vanadium: a population-based cohort study

BACKGROUND

Vanadium, an important pollutant produced from anthropogenic activities, has been suggested to be embryotoxic and fetotoxic in animal studies. However, little is known about its effects on humans. We aimed to assess the association of prenatal exposure to vanadium with the risk of adverse birth outcomes in babies born to women in China.

METHODS

For this population-based cohort study, the Healthy Baby Cohort, women were recruited from three cities in Hubei Province, China. Women included in this analysis were recruited from Wuhan Women and Children Medical Care Center, Wuhan. We measured urinary concentrations of vanadium and other metals simultaneously using inductively coupled plasma mass spectrometry. We used multivariable logistic regressions, with adjustment for potential confounders, to estimate the associations of natural logarithm transformed creatinine-corrected urinary vanadium (Ln-vanadium) concentrations as continuous variables and categorised into quartiles (Q; Q1: ≤0·84 μg/g creatinine, Q2: 0·84-1·40 μg/g creatinine, Q3: 1·40-2·96 μg/g creatinine, Q4: >2·96 μg/g creatinine, with the lowest quartile set as reference) with preterm delivery, early-term delivery, low birthweight, and being small for gestational age. We applied restricted cubic spline models to evaluate the dose-response relationships.

FINDINGS

Data from 7297 women recruited between Sept 22, 2012, and Oct 22, 2014, were included in this study. Urinary Ln-vanadium concentrations showed non-linear dose-response relationships with risk of preterm delivery (S-shaped, p<0·0001) and low birthweight (J-shaped, p=0·0001); the adjusted odds ratios (ORs) for increasing quartiles of urinary vanadium were 1·76 (95% CI 1·05-2·95) for Q2, 3·17 (1·96-5·14) for Q3, and 8·86 (5·66-13·86) for Q4 for preterm delivery, and 2·29 (95% CI 1·08-4·84) for Q2, 3·22 (1·58-6·58) for Q3, and 3·56 (1·79-7·10) for Q4 for low birthweight. Ln-vanadium concentrations were linearly associated with the risk of early-term delivery (linear, p<0·0001) and being small for gestational age (linear, p=0·0027), with adjusted ORs of 1·15 (95% CI 1·10-1·21) for early-term delivery and 1·12 (1·04-1·21) for being small for gestational age per unit increase in Ln-vanadium concentrations.

INTERPRETATION

Our findings reveal a relationship between prenatal exposure to higher levels of vanadium and increased risk of adverse birth outcomes, suggesting that vanadium might be a potential toxic metal for human beings. Further studies are needed to replicate the observed associations and investigate the interaction effects of prenatal exposure to different metals on adverse birth outcomes.

FUNDING

National Key R&D Plan of China, National Natural Science Foundation of China, and Fundamental Research Funds for the Central Universities, Key Laboratory of Environment and Health.

A novel method to remove chromium, vanadium and ammonium from vanadium industrial wastewater using a byproduct of magnesium-based wet flue gas desulfurization

A novel treatment for chromium, vanadium and ammonium from vanadium industrial wastewater using a byproduct of magnesium-based wet flue gas desulfurization is investigated. In the present study, the byproduct is used as a reductant for chromium and vanadium removal by chemical precipitation, and the residual magnesium ion can also be used to remove ammonium in the present of phosphate by struvite crystallization. Besides, the effects of main operational parameters (reaction pH, byproduct dosage and reaction time) on the heavy metal removal and ammonium removal (reaction pH, Mg²⁺:NH₄⁺:PO₄^3- molar ratio and reaction time) are investigated, and the reaction mechanism for this treatment technology is also proposed. Under the optimal conditions, the residual concentrations of chromium(IV), total chromium and vanadium are 0.046mg/L, 0.468mg/L and 0.06mg/L, respectively. The removal efficiency of ammonium is 95.72% and the residual concentrations of ammonium and phosphorus are 137.12mg/L and 5.49mg/L, respectively. Additionally, the precipitations are characterized using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscope-energy dispersive spectrometer (SEM-EDS) and thermogravimetry differential scanning calorimetry (TG-DSC), respectively. Finally, a resource utilization method of the precipitation sludge from this technology is also presented.

Brain Metal Distribution and Neuro-Inflammatory Profiles after Chronic Vanadium Administration and Withdrawal in Mice

Vanadium is a potentially toxic environmental pollutant and induces oxidative damage in biological systems including the central nervous system (CNS). Its deposition in brain tissue may be involved in the pathogenesis of certain neurological disorders which after prolonged exposure can culminate into more severe pathology. Most studies on vanadium neurotoxicity have been done after acute exposure but in reality some populations are exposed for a lifetime. This work was designed to ascertain neurodegenerative consequences of chronic vanadium administration and to investigate the progressive changes in the brain after withdrawal from vanadium treatment. A total of 85 male BALB/c mice were used for the experiment and divided into three major groups of vanadium treated (intraperitoneally (i.p.) injected with 3 mg/kg body weight of sodium metavanadate and sacrificed every 3 months till 18 months); matched controls; and animals that were exposed to vanadium for 3 months and thereafter the metal was withdrawn. Brain tissues were obtained after animal sacrifice. Sagittal cut sections of paraffin embedded tissue (5 μm) were analyzed by the Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to show the absorption and distribution of vanadium metal. Also, Haematoxylin and Eosin (H&E) staining of brain sections, and immunohistochemistry for Microglia (Iba-1), Astrocytes (GFAP), Neurons (Neu-N) and Neu-N + 4',6-diamidine-2'-pheynylindole dihydrochloride (Dapi) Immunofluorescent labeling were observed for morphological and morphometric parameters. The LA-ICP-MS results showed progressive increase in vanadium uptake with time in different brain regions with prediction for regions like the olfactory bulb, brain stem and cerebellum. The withdrawal brains still show presence of vanadium metal in the brain slightly more than the controls. There were morphological alterations (of the layering profile, nuclear shrinkage) in the prefrontal cortex, cellular degeneration (loss of dendritic arborization) and cell death in the Hippocampal CA1 pyramidal cells and Purkinje cells of the cerebellum, including astrocytic and microglial activation in vanadium exposed brains which were all attenuated in the withdrawal group. With exposure into old age, the evident neuropathology was microgliosis, while progressive astrogliosis became more attenuated. We have shown that chronic administration of vanadium over a lifetime in mice resulted in metal accumulation which showed regional variabilities with time. The metal profile and pathological effects were not completely eliminated from the brain even after a long time withdrawal from vanadium metal.

Vanadium exposure-induced striatal learning and memory alterations in rats

Occupational and environmental exposure to vanadium has been associated with toxicities in reproductive, respiratory, and cardiovascular systems. The knowledge on whether and how vanadium exposure caused neurobehavioral changes remains incomplete. This study was designed to investigate the changes in learning and memory following drinking water exposure to vanadium, and to conduct the preliminary study on underlying mechanisms. Male Sprague-Dawley rats were exposed to vanadium dissolved in drinking water at the concentration of 0.0, 0.5, 1.0 and 2.0g/L, as the control, low-, medium-, and high- dose groups, respectively, for 12 weeks. The results by the Morris water maze test showed that the time for the testing animal to find the platform in the high exposed group was increased by 82.9% and 49.7%, as compared to animals in control and low-dose groups (p<0.05). There were significantly fewer rats in the medium- and high- dose groups than in the control group who were capable of crossing the platform (p<0.05). Quantitation of vanadium by atomic absorption spectrophotometry revealed a significant dose-dependent accumulation of vanadium in striatum (r=0.931, p<0.01). Histopathological examination further demonstrated a degenerative damage in vanadium-exposed striatum. Interestingly, with the increase of the dose of vanadium, the contents of neurotransmitter ACh, 5-HT and GABA in the striatum increased; however, the levels of Syn1 was significantly reduced in the exposed groups compared with controls (p<0.05). These data suggest that vanadium exposure apparently reduces the animals' learning ability. This could be due partly to vanadium's accumulation in striatum and the ensuing toxicity to striatal structure and synaptic plasticity. Further research is warranted for mechanistic understanding of vanadium-induced neurotoxicity.

Comparative study of species sensitivity distributions based on non-parametric kernel density estimation for some transition metals

Transition metals in the fourth period of the periodic table of the elements are widely widespread in aquatic environments. They could often occur at certain concentrations to cause adverse effects on aquatic life and human health. Generally, parametric models are mostly used to construct species sensitivity distributions (SSDs), which result in comparison for water quality criteria (WQC) of elements in the same period or group of the periodic table might be inaccurate and the results could be biased. To address this inadequacy, the non-parametric kernel density estimation (NPKDE) with its optimal bandwidths and testing methods were developed for establishing SSDs. The NPKDE was better fit, more robustness and better predicted than conventional normal and logistic parametric density estimations for constructing SSDs and deriving acute HC5 and WQC for transition metals in the fourth period of the periodic table. The decreasing sequence of HC5 values for the transition metals in the fourth period was Ti > Mn > V > Ni > Zn > Cu > Fe > Co > Cr(VI), which were not proportional to atomic number in the periodic table, and for different metals the relatively sensitive species were also different. The results indicated that except for physical and chemical properties there are other factors affecting toxicity mechanisms of transition metals. The proposed method enriched the methodological foundation for WQC. Meanwhile, it also provided a relatively innovative, accurate approach for the WQC derivation and risk assessment of the same group and period metals in aquatic environments to support protection of aquatic organisms.

Infant and mother related outcomes from exposure to metals with endocrine disrupting properties during pregnancy

BACKGROUND

Endocrine-related adverse health effects from exposure to heavy metals such as lead, arsenic, cadmium, and mercury are yet to be adequately described. The purpose of this review was to gain insight into maternal exposure to heavy metals, and to identify potential endocrine-related adverse health effects in the mother and the infant.

METHODS

Relevant databases were searched for original research reports and a total of 46 articles were retained for scrutiny. Required data was extracted from these studies and their methodology was assessed.

RESULTS

Impaired fetal growth was observed from exposure to all endocrine disrupting metals, while exposure to lead and arsenic were associated with spontaneous abortion, stillbirth and neonatal deaths. Maternal exposure to arsenic was associated with impaired glucose tolerance in these mothers.

CONCLUSION

Impaired fetal growth, fetal loss, and neonatal deaths were significantly associated with heavy metals exposure during pregnancy; however, hypertension and gestational diabetes require further investigation.

Comparison of distribution and toxicity following repeated oral dosing of different vanadium oxide nanoparticles in mice

Vanadium is an important ultra-trace element derived from fuel product combustion. With the development of nanotechnology, vanadium oxide nanoparticles (VO NPs) have been considered for application in various fields, thus the possibility of release into the environment and human exposure is also increasing. Considering that verification of bioaccumulation and relevant biological responses are essential for safe application of products, in this study, we aimed to identify the physicochemical properties that determine their health effects by comparing the biological effects and tissue distribution of different types of VO NPs in mice. For this, we prepared five types of VO NPs, commercial (C)-VO2 and -V2O5 NPs and synthetic (S)-VO2, -V2O3, and -V2O5 NPs. While the hydrodynamic diameter of the two types of C-VO NPs was irregular and impossible to measure, those of the three types of S-VO NPs was in the range of 125-170nm. The S- and C-V2O5 NPs showed higher dissolution rates compared to other VO NPs. We orally dosed the five types of VO NPs (70 and 210μg/mouse, approximately 2 and 6mg/kg) to mice for 28 days and compared their biodistribution and toxic effects. We found that S-V2O5 and S-V2O3 NPs more accumulated in tissues compared to other three types of VO NPs, and the accumulated level was in order of heart>liver>kidney>spleen. Additionally, tissue levels of redox reaction-related elements and electrolytes (Na(+), K(+), and Ca(2+)) were most clearly altered in the heart of treated mice. Notably, all S- and C-VO NPs decreased the number of WBCs at the higher dose, while total protein and albumin levels were reduced at the higher dose of S-V2O5 and S-V2O3 NPs. Taken together, we conclude that the biodistribution and toxic effects of VO NPs depend on their dissolution rates and size (surface area). Additionally, we suggest that further studies are needed to clarify effects of VO NPs on functions of the heart and the immune system.

Hazards identified and the need for health risk assessment in the South African mining industry

Although mining plays a prominent role in the economy of South Africa, it is associated with many chemical hazards. Exposure to dust from mining can lead to many pathological effects depending on mineralogical composition, size, shape and levels and duration of exposure. Mining and processing of minerals also result in occupational exposure to toxic substances such as platinum, chromium, vanadium, manganese, mercury, cyanide and diesel particulate. South Africa has set occupational exposure limits (OELs) for some hazards, but mine workers are still at a risk. Since the hazard posed by a mineral depends on its physiochemical properties, it is recommended that South Africa should not simply adopt OELs from other countries but rather set her own standards based on local toxicity studies. The limits should take into account the issue of mixtures to which workers could be exposed as well as the health status of the workers. The mining industry is also a source of contamination of the environment, due inter alia to the large areas of tailings dams and dumps left behind. Therefore, there is need to develop guidelines for safe land-uses of contaminated lands after mine closure.

Vanadium (V) and magnesium (Mg) - In vivo interactions: A review

Vanadium (V) and magnesium (Mg) arouse interest of many research centres worldwide. Many aspects of their action have already been recognized but some of them have not been fully elucidated yet. Relatively little is known about the mechanisms of absorption, transport, and excretion of V. There is also a lack of sufficient data about the most sensitive biomarkers of V toxicity and the mechanisms of its toxic action, which have not been fully explained yet. There is also a lack of comprehensive research on the consequences, character, and mechanisms of mutual interactions of V (which has strong pro-oxidant properties) with elements with an antioxidant potential such as Mg, the recognition of which, besides the cognitive value, may have great practical importance. It should be highlighted that the question of interactions between elements is always up to date and it is still an important issue in toxicology. A comprehensive research on interactions of V with Mg can be particularly important in the studies of the usage of V (which has a narrow margin of safety) in the treatment of certain diseases in humans, especially diabetes, which is accompanied by changes in the level of Mg in the tissues and weakening of the antioxidant barrier and oxidative stress. Therefore, the aspect concerning the possible interaction of V (as a potent pro-oxidant) with Mg (as an antioxidant) was the subject of our special interest. In addition, the examination of the effects of the interactions between V and Mg is very important especially for extending the knowledge of the mechanism of the influence of V on the organism and a potential role of Mg (which is characterized by a wide therapeutic window) in prevention of V toxicity. This review summarizes the most important results obtained from our experiments in a rodent model referring to the interactions of V with Mg on the background of the in vivo experimental data published by other researchers of this issue. Our studies have shown that V and Mg supplied in combination are able to modulate the response in an interactive manner to produce a specific effect that is distinct from that observed during separate administration thereof. The present report also provides the most important information about the effects of the action of V and Mg with other metals.