Accidental ingestion of sodium molybdate at the workplace followed by short-term biomonitoring.

INTRODUCTION: Most of the molybdenum (Mo) is used in metallurgical applications, the tetrathiomolybdate form is an experimental chelating agent for Wilson's disease. Human data of acute Mo exposure are lacking and, no report of no-observed-adverse-effect level (NOAEL) has been described until now. Case-study: We report a case of acute occupational exposure to molybdenum, with the related plasma and urine molybdenum concentrations, caused by an accidental ingestion of a sip of an anti-corrosion liquid for metal containing sodium molybdate. Our purpose was to evaluate potential systemic toxicity of molybdenum and to evaluate the dose-response/dose-effect relationship. We estimated the amount of ingested molybdenum to make a mg/kg relationship and performed repeated urine and plasma molybdenum determinations. The patient was hospitalized for three days to monitor possible development of acute symptoms/biochemical alterations. DISCUSSION: We estimated the amount of the sip around 50 ml, with an estimation of a total of 5 gr of sodium molybdate that, for the patient bodyweight of 80 kg, would mean 62,5 mg/kg of ingested Mo. Blood and urine samples collected 2 hours after ingestion showed 50 mcg/L (reference range: 0.43 - 1.8 mcg/L) and 630 mcg/L (refence range: up to 116 mcg/L) of Mo respectively, confirming acute exposure. The patients remained asymptomatic confirming that an estimated oral dose of Mo of 62.5 mg/kg was not associated with adverse effects. CONCLUSIONS: Our value, being extrapolated by a single case, will require further confirmations from other studies to allow a full evaluation of a NOAEL. Nevertheless, it does not preclude its use in evaluating the probable absence of adverse effect in the context of acute Mo exposure.

[Studies on markers of exposure and early effect in areas with arsenic pollution: methods and results of the project SEpiAs. Epidemiological surveillance in areas with environmental pollution by natural or anthropogenic arsenic]. / Studi su marcatori di esposizione ed effetto precoce in aree con inquinamento da arsenico: metodi e risultati del progetto SEpiAs. Sorveglianza epidemiologica in aree interessate da inquinamento ambientale da arsenico di origine naturale o antropica (SEpiAS CCM 2010).

INTRODUCTION: Arsenic and its inorganic compounds are classified as carcinogenic to humans. Exposures to inorganic arsenic (iAs) in drinking water are associated with both carcinogenic and non-carcinogenic effects. The risk assessment of exposures to low-moderate levels of environmental arsenic (As) is a challenging objective for research and public health. The SEpiAs study, funded by the Italian Ministry of Health (CCM), was carried out in four areas with arsenic pollution prevalently of natural origin, Amiata and Viterbo areas, or of industrial origin, Taranto and Gela. MATERIALS AND METHODS: 271 subjects (132 men) aged 20-44, were randomly sampled stratifying by area, gender and age classes. Individual data on residential history, socio-economic status, environmental and occupational exposures, lifestyle and dietary habits, were collected through interviews using questionnaire. In urine samples of recruited subjects, the concentration of inorganic arsenic (iAs) and methylated species (MMA, DMA) was measured using inductively coupled mass spectrometer (DRCICP- MS), after chromatographic separation (HPLC). Molecular biomarkers and biomarkers of DNA damage, as well as markers of cardiovascular risk were measured The distributions of iAs and iAs+MMA+DMA were described by area and gender, geometric mean (GM), percentiles and standard deviation (SD). The associations between As species and variables collected by questionnaire were evaluated by multiple regression analysis. RESULTS: Results showed a high variability of As species within and among areas. Gela and Taranto samples showed higher iAs concentration compared to Viterbo and Amiata. Subjects with iAs>1,5 µg/L or iAs+MMA+DMA>15 µg/L (thresholds suggested by the Italian Society of Reference Values), are 137 (50,6%) and 68 (25,1%), respectively. A positive association between iAs and use of drinking water emerged in the Viterbo sample, between iAs and occupational exposure in the Gela and Taranto samples. Fish consumption was associated with higher iAs concentration in the whole sample, and particularly in men of the Gela sample. Similar results were observed for iAs+MMA+DMA. Subjects with iAs or iAs+MMA+DMA values higher than the 95th percentile were 15 (6Taranto, 5 Gela, 3Viterbo, 1 Amiata). The relationships between iAs and organic species (methylation efficiency ratios) were different between sex in the four areas. The relevance of polymorphisms AS3MT Met287Thr, GST-T1, GST-M1, OGG1 was confirmed. The analysis of carotid intima-media-thickness showed normal values, but higher among man of Viterbo, Taranto and Gela areas. CONCLUSIONS: Results are informative of exposure to inorganic and organic As in large or at least non-negligible quotas of the samples. The SEpiAs results suggest a further deepening on routes of exposure to arsenic species, and support the recommendation to implement primary prevention measures to reduce population exposure.

Correlation Between Co Levels in Hair and Blood of Patients Who Underwent Metal-on-metal Hip Arthroplasty.

Background: The purpose of this paper is to study the dependence of Co levels in hair on Co levels in blood after metal-on-metal (MoM) hip replacement and prove the suitability of hair analysis coupled to blood analysis in the decision process regarding implant revision evaluation. Methods: Hair samples of 19 MoM patients having both well-functioning and malfunctioning implants and Co mass concentration levels in blood between 0.2 µg L-1 and 221.0 µg L-1 were included. A method based on inductively coupled plasma mass spectrometry was validated and used to measure the Co level in hair. Results: The Co mass fraction in the hair of patients ranged between 0.011 mg kg-1 and 0.712 mg kg-1. A correlation analysis showed a statistically significant positive correlation (r = 0.932, P < .001) between Co in the hair and that in the blood in the full-level range and a statistically nonsignificant positive correlation (r = 0.595, P = .091) in the low-level range. Conclusions: A correlation between the Co level in the hair and that in the blood exists when the latter is clearly above the 7 µg L-1 mass concentration threshold suggested for implant revision evaluation. The correlation disappears when the Co level in blood approaches or falls down the mass concentration threshold and that in the hair approaches or falls within the normal population range of 0.004-0.14 mg kg-1. Accordingly, clinicians could consider a hair analysis coupled to a blood analysis to assess the revision of malfunctioning MoM implants that release metals in patient's body.

Toxic effects of mercury in humans and mammals.

The clinical manifestations of methylmercury toxicity do not differ greatly according to the acute and/or chronic methylmercury overexposure.

Concentration of Metals and Trace Elements in the Normal Human and Rat Thyroid: Comparison with Muscle and Adipose Tissue and Volcanic Versus Control Areas.

Background: The concentration of trace elements and metals in the thyroid is the result of exposure, uptake, retention, and clearance. The specificity and selectivity of thyroid capacity to concentrate these elements relative to other tissues are not known. To obtain this information, we measured the tissue concentration of 26 elements in the thyroid, muscle, and fat of euthyroid human subjects and also in normal rats. Methods: At programmed surgery, small (<1 g) tissue fragments were collected in 77 euthyroid subjects. Macroscopically normal thyroid tissue, sternothyroid muscle, and neck subcutaneous fat samples were excised, and thyroid tissue was confirmed to be morphologically normal through microscopy. Tissue specimens (thyroid, hindlimb muscle, and abdominal fat) were also obtained from normal rats. Measurements of trace elements were performed on tissues using inductively coupled plasma mass spectrometry (DRC-ICP-MS). Results: Only 19 of the 26 investigated elements were measurable as 7 elements were below the limit of detection. The ranking concentration in human thyroid tissue, not considering iodide, indicated that Zn, Br, Cu, Cr, Se, and Mn represented over 95% of the measured elements. A similar ranking was observed in the rat thyroid. A comparison with other tissues indicated that in addition to I, also Br, Mn, Se, and Sn were significantly more concentrated in the thyroid, and this was also the case for the recognized carcinogens As, Cd, and Hg. As and Hg, but not Cd (which was not detectable in any of the rat tissues), were also more concentrated in the rat thyroid. Since human thyroid specimens were also obtained from residents of a volcanic area, where environmental pollution may cause human biocontamination, we compared the trace element concentration in specimens from the volcanic area with controls. Many trace elements were slightly, but not significantly, increased in the volcanic area specimens. Conclusions: In the normal human thyroid, many trace elements, including Br, Mn, Se, and Sn, and the recognized carcinogens, As, Cd, and Hg, are significantly more concentrated than in muscle and fat of the same individual. Similar data were observed in rats. The reason for the differential element accumulation in the thyroid is unclear; a better understanding may be useful to further clarify thyroid biology.

Treatment with lithium carbonate does not improve disease progression in two different strains of SOD1 mutant mice.

It has been shown that chronic treatment with lithium carbonate (Li(2)CO(3)) in presymptomatic SOD1G93A transgenic male mice, a model of ALS, was able to remarkably increase their lifespan through the activation of autophagy and the promotion of mitochondriogenesis and neurogenesis. This prompted us to test the lithium effect also in female SOD1G93A mice with two phenotypes of different disease severity. Female SOD1G93A mice of C57BL/6J or 129S2/Sv genetic background were treated daily with Li(2)CO(3) 37 mg/kg (1 mEq/kg) i.p. starting from age 75 days until death. Grip strength, latency to fall on rotarod and body weight were monitored twice weekly. At the time of death the spinal cord was removed to assess the number of motor neurons and to measure the expression of a marker of autophagy (LCII) and the activity of mitochondrial complex IV. We observed a significant anticipation of the onset and reduced survival in 129Sv/G93A and no effect in C57/G93A mice treated with lithium compared to vehicle treated mice. Moreover, lithium neither exerted neuroprotective effects nor increased the expression of LCII and the activity of mitochondrial complex IV in the spinal cord. The present study does not identify any therapeutic or neuroprotective effect of lithium in SOD1G93A female mice.

Dietary exposure estimates of twenty-one trace elements from a Total Diet Study carried out in Pavia, Northern Italy.

The significant role of trace elements in human health is well documented. Trace elements are those compounds that need to be present in the human diet to maintain normal physiological functions. However, some microelements may become harmful at high levels of exposure, or, on the other hand, may give rise to malnutrition, when their exposure is too low. The aim of the present study was to provide a reliable estimate of the dietary exposure of twenty-one trace elements in a Northern Italian area. For this purpose, trace element analyses were undertaken on total diet samples collected from a university cafeteria in Pavia, Northern Italy. The average daily exposure for the adult people was calculated on the basis of food consumption frequency, portion size and trace element levels in foodstuffs. The mean exposure values satisfy the Italian RDA for all the essential trace elements, except for Fe exposure in females, and are well below the Provisional Tolerable Daily Intake for all the toxic compounds, showing that the probability of dietary exposure to health risks is overall small. As far as Fe exposure is concerned, a potential risk of anaemia in the female adult population should be considered, then studies aimed at evaluating the Fe nutritional status of adult Italian women should be addressed. In conclusion, while not excluding the possibility that the daily exposure determined in the present study may not be representative of the population as a whole, this study provides a good estimate of the Italian adult consumer exposure to twenty-one trace elements.

Transhepatic arterial chemoembolization with oxaliplatin-eluting microspheres (OEM-TACE) for unresectable hepatic tumors.

BACKGROUND: While conventional transhepatic arterial chemoembolization (TACE) is accepted worldwide as an effective treatment for patients with unresectable hepatocellular carcinoma (HCC), its use in other hepatic tumors is not supported by randomized studies. Preliminary results have shown that new drug-eluting microspheres (DEM) seem to optimize TACE procedures. The aim of this study was to evaluate the capability of HepaSphere to load oxaliplatin and their pharmacokinetic outcome. The feasibility and safety of treatment with oxaliplatin-eluting microspheres (OEM-TACE) was also evaluated in patients with unresectable liver metastasis of colorectal cancer and unresectable intrahepatic cholangiocarcinoma. PATIENTS AND METHODS: An inductively coupled plasma mass spectrometer (ICP-MS) was used to quantify the oxaliplatin bound to microspheres and the oxaliplatin in liver biopsies. Fifteen patients (8 with colorectal carcinoma liver metastases, 7 with intrahepatic cholangiocarcinoma) were treated with 27 sessions of OEM-TACE. RESULTS: The data suggested that the microspheres can bind oxaliplatin entirely. The pharmacokinetic parameters were significantly different between the OEM-TACE patients and a control group of patients treated with oxaliplatin chemotherapy. The mean oxaliplatin concentration within the tumor was twenty-times higher than the extratumoral liver concentration in the OEM-TACE patients. According to response evaluating criteria in solid tumors (RECIST), stable disease was observed in 8 out of the 15 patients (53.3%), a partial response in 2 (13.3%) and intrahepatic or extrahepatic tumor progression in 5 out of the 15 patients (33.3%). No major adverse event (AE G3/4) occurred. CONCLUSION: TACE with oxaliplatin-loaded microspheres is a safe and feasible treatment without major adverse events and with a favorable pharmacokinetic profile.

Dental amalgam, mercury toxicity, and renal autoimmunity.

Chronic exposure to elemental metallic mercury may induce an immunological glomerular disease. Since humans are exposed to mercury vapor (Hg0) from dental amalgam restorations and kidney is an important target organ of mercury vapor and mercury deposition in kidney increases proportionally with the dose, our aim was to test the occurrence of specific antibodies to antiglomerular basement membrane (anti-GBM-IgG) among individuals with adverse effects to mercury from dental amalgam fillings. We selected a group of patients (n=24) with a history of long-term exposure to mercury vapor from mercury-containing amalgam fillings and showing adverse effects that were laboratory confirmed. Enzyme-linked immunosorbent assays (ELISAs) were used to evaluate serum levels of antibodies to anti-GBM-IgG. None of the patients showed evidence of anti-GBM autoimmunity, either in subgroups with strong allergy to mercury or its compounds (i.e., organic mercury) or in those patients who had past thimerosal-containing vaccines coverage (7 of 24). There was no evidence of the presence of circulating anti-GBM antibodies in subjects suffering from adverse events due to long-term exposure to mercury from dental amalgams, even in individuals who presented allergy to mercury.

Urinary Arsenic in Human Samples from Areas Characterized by Natural or Anthropogenic Pollution in Italy.

Arsenic is ubiquitous and has a potentially adverse impact on human health. We compared the distribution of concentrations of urinary inorganic arsenic plus methylated forms (uc(iAs+MMA+DMA)) in four Italian areas with other international studies, and we assessed the relationship between uc(iAs+MMA+DMA) and various exposure factors. We conducted a human biomonitoring study on 271 subjects (132 men) aged 20-44, randomly sampled and stratified by area, gender, and age. Data on environmental and occupational exposure and dietary habits were collected through a questionnaire. Arsenic was speciated using chromatographic separation and inductively coupled mass spectrometry. Associations between uc(iAs+MMA+DMA) and exposure factors were evaluated using the geometric mean ratio (GMR) with a 90% confidence interval by stepwise multiple regression analysis. The 95th percentile value of uc(iAs+MMA+DMA) for the whole sample (86.28 µg/L) was higher than other national studies worldwide. A statistical significant correlation was found between uc(iAs+MMA+DMA) and occupational exposure (GMR: 2.68 [1.79-4.00]), GSTT gene (GMR: 0.68 [0.52-0.80]), consumption of tap water (GMR: 1.35 [1.02-1.77]), seafood (GMR: 1.44 [1.11-1.88]), whole milk (GMR: 1.34 [1.04-1.73]), and fruit/vegetables (GMR: 1.37 [1.03-1.82]). This study demonstrated the utility of uc(iAs+MMA+DMA) as a biomarker to assess environmental exposure. In a public health context, this information could be used to support remedial action, to prevent individuals from being further exposed to environmental arsenic sources.

Protective effect of erythropoietin and its carbamylated derivative in experimental Cisplatin peripheral neurotoxicity.

PURPOSE: Antineoplastic drugs, such as cisplatin (CDDP), are severely neurotoxic, causing disabling peripheral neuropathies with clinical signs known as chemotherapy-induced peripheral neurotoxicity. Cotreatment with neuroprotective agents and CDDP has been proposed for preventing or reversing the neuropathy. Erythropoietin given systemically has a wide range of neuroprotective actions in animal models of central and peripheral nervous system damage. However, the erythropoietic action is a potential cause of side effects if erythropoietin is used for neuroprotection. We have successfully identified derivatives of erythropoietin, including carbamylated erythropoietin, which do not raise the hematocrit but retain the neuroprotective action exerted by erythropoietin. EXPERIMENTAL DESIGN: We have developed previously an experimental chemotherapy-induced peripheral neurotoxicity that closely resembles CDDP neurotoxicity in humans. The present study compared the effects of erythropoietin and carbamylated erythropoietin (50 microg/kg/d thrice weekly) on CDDP (2 mg/kg/d i.p. twice weekly for 4 weeks) neurotoxicity in vivo. RESULTS: CDDP given to Wistar rats significantly lowered their growth rate (P < 0.05), with slower sensory nerve conduction velocity (P < 0.001) and reduced intraepidermal nerve fibers density (P < 0.001 versus controls). Coadministration of CDDP and erythropoietin or carbamylated erythropoietin partially but significantly prevented the sensory nerve conduction velocity reduction. Both molecules preserved intraepidermal nerve fiber density, thus confirming their neuroprotective effect at the pathologic level. The protective effects were not associated with any difference in platinum concentration in dorsal root ganglia, sciatic nerve, or kidney specimens. CONCLUSIONS: These results widen the spectrum of possible use of erythropoietin and carbamylated erythropoietin as neuroprotectant drugs, strongly supporting their effectiveness.

Intake of Boron, Cadmium, and Molybdenum enhances rat thyroid cell transformation.

BACKGROUND: Epidemiologic data in volcanic areas suggest that environmental factors might be involved in the increase of thyroid cancer (TC) incidence. Recent reports indicate that several heavy metals and metalloids are increased in volcanic areas. This study aims to evaluate the combined effect of three of these elements Boron (B), Cadmium (Cd), and Molybdenum (Mo) - all increased in the volcanic area of Mt. Etna, in Italy - on thyroid tumorigenesis in the rat. METHODS: Female Wistar rats prone to develop thyroid tumors by low-iodine diet and methimazole treatment received ad libitum drinking water supplemented with B, Cd, and Mo at concentrations in the range found in the urine samples of residents of the volcanic area. At 5 and 10 months animals were euthanized, and their thyroid analysed. Statistical analysis was performed with a 2-way unpaired t-test. RESULTS: No toxic effect of the three elements on the growth of the animals was observed. A significant increase of histological features of transformation was observed in thyroid follicular cells of rats treated with B, Cd, and Mo compared with those of control group. These abnormalities were associated with decreased iodine content in the thyroid. CONCLUSIONS: This study provides the evidence that slightly increased environmental concentrations of B, Cd, and Mo can accelerate the appearance of transformation marks in the thyroid gland of hypothyroid rats.

Brief exposure to nanosized and bulk titanium dioxide forms induces subtle changes in human D384 astrocytes.

Although nanosized-titanium dioxide particles (TiO2NPs)-containing products are constantly placed on the market, little is known about their possible impact on human health, even regarding to CNS effects. In this study, mechanistic pathways, by which TiO2NPs induce cellular damage and death, have been investigated in human (astrocytes-like) D384 cells and comparatively weighed against the effects produced by the bulk counterpart. Cellular signals evaluated by multiple set of in vitro tests after 24h exposure to TiO2NP concentrations (0.5-125µg/ml) were: ROS production, p-p53, p53, p21, Bax, Bcl-2 and caspase 3. TiO2 cellular uptake was also estimated by both light microscopy and ICP-MS. ROS were generated starting at 1.5µg/ml and further increased at the highest concentrations (≥31µg/ml). At the same low concentration, an increased expression of p-p53, p53, p21, Bax, and activated caspase3 were also observed. Parallely, Bcl-2 decreased along with TiO2NP concentration increase. Similar alterations were observed when testing TiO2 bulk: cellular checkpoint perturbations were associated with rising intracellular Ti. The present data demonstrated that low TiO2NP concentrations were capable, after 24h, to induce subtle cellular perturbation in D384 cells after a single cell treatment, supporting the evidence that both oxidative stress and apoptotic mechanisms may occur in this type of CNS cells.

N-Acetyl-Cysteine as Effective and Safe Chelating Agent in Metal-on-Metal Hip-Implanted Patients: Two Cases.

Systemic toxicity associated with cobalt (Co) and chromium (Cr) containing metal hip alloy may result in neuropathy, cardiomyopathy, and hypothyroidism. However clinical management concerning chelating therapy is still debated in literature. Here are described two metal-on-metal hip-implanted patients in which N-acetyl-cysteine decreased elevated blood metal levels. A 67-year-old male who underwent Co/Cr hip implant in September 2009 referred to our Poison Control Centre for persisting elevated Co/Cr blood levels (from March 2012 to November 2014). After receiving oral high-dose N-acetyl-cysteine, Co/Cr blood concentrations dropped by 86% and 87% of the prechelation levels, respectively, and persisted at these latter concentrations during the following 6 months of follow-up. An 81-year-old female who underwent Co/Cr hip implant in January 2007 referred to our Centre for detection of high Co and Cr blood levels in June 2012. No hip revision was indicated. After a therapy with oral high-dose N-acetyl-cysteine Co/Cr blood concentrations decreased of 45% and 24% of the prechelation levels. Chelating agents reported in hip-implanted patients (EDTA, DMPS, and BAL) are described in few cases. N-acetyl-cysteine may provide chelating sites for metals and in our cases reduced Co and Cr blood levels and resulted well tolerable.

Increased thyroid cancer incidence in a basaltic volcanic area is associated with non-anthropogenic pollution and biocontamination.

The increased thyroid cancer incidence in volcanic areas suggests an environmental effect of volcanic-originated carcinogens. To address this problem, we evaluated environmental pollution and biocontamination in a volcanic area of Sicily with increased thyroid cancer incidence. Thyroid cancer epidemiology was obtained from the Sicilian Regional Registry for Thyroid Cancer. Twenty-seven trace elements were measured by quadrupole mass spectrometry in the drinking water and lichens (to characterize environmental pollution) and in the urine of residents (to identify biocontamination) in the Mt. Etna volcanic area and in adjacent control areas. Thyroid cancer incidence was 18.5 and 9.6/10(5) inhabitants in the volcanic and the control areas, respectively. The increase was exclusively due to the papillary histotype. Compared with control areas, in the volcanic area many trace elements were increased in both drinking water and lichens, indicating both water and atmospheric pollution. Differences were greater for water. Additionally, in the urine of the residents of the volcanic area, the average levels of many trace elements were significantly increased, with values higher two-fold or more than in residents of the control area: cadmium (×2.1), mercury (×2.6), manganese (×3.0), palladium (×9.0), thallium (×2.0), uranium (×2.0), vanadium (×8.0), and tungsten (×2.4). Urine concentrations were significantly correlated with values in water but not in lichens. Our findings reveal a complex non-anthropogenic biocontamination with many trace elements in residents of an active volcanic area where thyroid cancer incidence is increased. The possible carcinogenic effect of these chemicals on the thyroid and other tissues cannot be excluded and should be investigated.