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Sample records for acute cadmium fume

  1. Flow injection determination of lead and cadmium in hair samples from workers exposed to welding fumes

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    Cespon-Romero, R.M. [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, 15782-Santiago de Compostela (Spain); Yebra-Biurrun, M.C. [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, 15782-Santiago de Compostela (Spain)], E-mail: qncayebi@usc.es

    2007-09-26

    A flow injection procedure involving continuous acid leaching for lead and cadmium determination in hair samples of persons in permanent contact with a polluted workplace environment by flame atomic absorption spectrometry is proposed. Variables such as sonication time, nature and concentration of the acid solution used as leaching solution, leaching temperature, flow-rate of the continuous manifold, leaching solution volume and hair particle size were simultaneously studied by applying a Plackett-Burman design approach. Results showed that nitric acid concentration (leaching solution), leaching temperature and sonication time were statistically significant variables (confidence interval of 95%). These last two variables were finally optimised by using a central composite design. The proposed procedure allowed the determination of cadmium and lead with limits of detection 0.1 and 1.0 {mu}g g{sup -1}, respectively. The accuracy of the developed procedure was evaluated by the analysis of a certified reference material (CRM 397, human hair, from the BCR). The proposed method was applied with satisfactory results to the determination of Cd and Pb in human hair samples of workers exposed to welding fumes.

  2. Biomonitoring for iron, manganese, chromium, aluminum, nickel and cadmium in workers exposed to welding fume: a preliminary study

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    Mulyana

    2015-05-01

    Full Text Available The control of exposure to welding fumes is increasing importance in promoting a healthy, safe and productive work environment. This study is a case-control design, random study was conducted among welder (56 subjects and non welder (39 subjects with more than 1 years experience in the same job task in an automotive parts manufactory within the industrial area at Cikarang in 2013. All subjects were completed physical examination, informed consent and questionnaire. Blood heavy metals were determined by Inductively-Coupled Plasma Mass Spectrometry (ICP-MS. Whole blood iron, manganese, chromium and lead in welder were higher than non-welder, but not different for aluminum, nickel and cadmium. In welder, chromium and manganese correlated with smoking status, cadmium correlated with age and smoking status. In multivariate analysis, wholeblood cadmium correlates with age and smoking status.

  3. Effects of asphalt fume condensate exposure on acute pulmonary responses

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    Ma, J.Y.C.; Barger, M.W.; Castranova, V. [Health Effects Lab. Div., National Inst. for Occupational Safety and Health, Morgantown, WV (United States); Kriech, A.J. [Heritage Research Group, Indianapolis, IN (United States)

    2000-10-01

    The present study was carried out to characterize the effects of in vitro exposure to paving asphalt fume condensate (AFC) on alveolar macrophage (AM) functions and to monitor acute pulmonary responses to in vivo AFC exposure in rats. Methods: For in vitro studies, rat primary AM cultures were incubated with various concentrations of AFC for 24 h at 37 C. AM-conditioned medium was collected and assayed for lactate dehydrogenase (LDH) as a marker of cytotoxicity. Tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-1 (IL-1) production were assayed in AM-conditioned medium to monitor AM function. The effect of AFC on chemiluminescence (CL) generated by resting AM or AM in response to zymosan or PMA stimulation was also determined as a marker of AM activity. For in vivo studies, rats received either (1) a single intratracheal (IT) instillation of saline, or 0.1 mg or 0.5 mg AFC and were killed 1 or 3 days later; or (2) IT instillation of saline, or 0.1, 0.5, or 2 mg AFC for three consecutive days and were killed the following day. Differential counts of cells harvested by bronchoalveolar lavage were measured to monitor inflammation. Acellular LDH and protein content in the first lavage fluid were measured to monitor damage. CL generation, TNF-{alpha} and IL-1 production by AM were assayed to monitor AM function. Results: In vitro AFC exposure at <200 {mu}g/ml did not induce cytotoxicity, oxidant generation, or IL-1 production by AM, but it did cause a small but significant increase in TNF-{alpha} release from AM. In vitro exposure of AM to AFC resulted in a significant decline of CL in response to zymosan or PMA stimulation. The in vivo studies showed that AFC exposure did not induce significant neutrophil infiltration or alter LDH or protein content in acellular lavage samples. Macrophages obtained from AFC-exposed rats did not show significant differences in oxidant production or cytokine secretion at rest or in response to LPS in comparison with control

  4. Exposure to Cooking Fumes and Acute Reversible Decrement in Lung Functional Capacity

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    Masoud Neghab

    2017-10-01

    Full Text Available Background: Being exposed to cooking fumes, kitchen workers are occupationally at risk of multiple respiratory hazards. No conclusive evidence exists as to whether occupational exposure to these fumes is associated with acute and chronic pulmonary effects and symptoms of respiratory diseases. Objective: To quantify the exposure levels and evaluate possible chronic and acute pulmonary effects associated with exposure to cooking fumes. Methods: In this cross-sectional study, 60 kitchen workers exposed to cooking fumes and 60 unexposed employees were investigated. The prevalence of respiratory symptoms among these groups was determined through completion of a standard questionnaire. Pulmonary function parameters were also measured before and after participants' work shift. Moreover, air samples were collected and analyzed to quantify their aldehyde, particle, and volatile organic contents. Results: The mean airborne concentrations of formaldehyde, acetaldehyde, and acrolein was 0.45 (SD 0.41, 0.13 (0.1, and 1.56 (0.41 mg/m3, respectively. The mean atmospheric concentrations of PM1, PM2.5, PM7, PM10, and total volatile organic compounds (TVOCs was 3.31 (2.6, 12.21 (5.9, 44.16 (16.6, 57 (21.55 μg/m3, and 1.31 (1.11 mg/m3, respectively. All respiratory symptoms were significantly (p<0.05 more prevalent in exposed group. No significant difference was noted between the pre-shift mean of spirometry parameters of exposed and unexposed group. However, exposed workers showed cross-shift decrease in most spirometry parameters, significantly lower than the pre-shift values and those of the comparison group. Conclusion: Exposure to cooking fumes is associated with a significant increase in the prevalence of respiratory symptoms as well as acute reversible decrease in lung functional capacity.

  5. Acute Inhalation Exposure to Titanium Ethanolate as a Possible Cause of Metal Fume Fever

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    M Ahmadimanesh

    2014-04-01

    Full Text Available Occupational inhalation exposure to noxious agents is not uncommon. Herein, we present a 26-year-old male student who had accidental acute inhalation exposure to a large quantity of titanium ethanolate and hydrogen chloride in chemistry lab. He was referred to the emergency department of our hospital with low-grade fever, dyspnea, headache, fatigue and myalgia. After 24 hrs of symptomatic treatment (oxygen therapy and acetaminophen, the fever was subsided and the patient discharged home in a good clinical condition. The presented symptoms could be interpreted as a form of metal fume fever. It can therefore be concluded that organo-metallic compound of titanium metal may have the potential to produce metal fume fever in human.

  6. Inflammatory response to acute exposure to welding fumes during the working day

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    Merja Järvelä

    2013-04-01

    Full Text Available Objectives: To investigate cardiorespiratory and inflammatory responses in male workers following exposure to welding fumes and airborne particles in actual workplace conditions. Materials and Methods: We measured blood leukocytes and their differential counts, platelet count, hemoglobin, sensitive C-reactive protein, fibrinogen, E-selectin, IL-(interleukin1β, IL-6, IL-8, tumor necrosis factor alpha (TNF-α and endothelin-1 in blood samples of twenty workers before and after their working day. We also studied peak expiratory flow (PEF, forced expiratory volume in one second (FEV1, and exhaled nitric oxide (NO. We assessed heart rate variability (HRV by obtaining 24-hour ambulatory electrocardiograms. Results: The total blood leukocytes and neutrophils increased after the work shift, whereas IL-1β and E-selectin decreased significantly. There were no tatistically significant changes in exhaled NO, FEV1, PEF or HRV. Conclusion: Occupational exposure to welding fumes and particles caused a slight, acute inflammatory effect estimated based on the increased values of leukocytes and neutrophils in blood and a decrease in the interleukin 1β and E-selectin values, but no changes in the pulmonary function (exhaled NO, FEV1, PEF or HRV during the working day were observed.

  7. Toxicological Investigation of Acute Carbon Monoxide Poisoning in Four Occupants of a Fuming Sport Utility Vehicle

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    Martin Nnoli

    2014-11-01

    Full Text Available Background: This toxicological investigation involves a report on the death of four occupants of a sport utility vehicle on one of the major busy Federal roads of Nigeria where they were held for up to three hours in a traffic jam while the car was steaming. Methods: Autopsy was executed using the standard procedure and toxicological analysis was done using simple spectrophotometric method to establish the level of carboxyhaemoglobin (HbCO in peripheral blood in the four occupants. Results: The autopsy report indicated generalized cyanosis, sub-conjuctival hemorrhages, marked laryngo-trachea edema with severe hyperemia with frothy fluid discharges characteristic of carbon monoxide poisoning. Toxicological report of the level of HbCO in part per million (ppm in the peripheral blood of the four occupants was A= 650 ppm; B= 500 ppm; C= 480 ppm, and D= 495 ppm against the maximum permissible level of 50 ppm. Conclusion: The sudden death of the four occupants was due to excessive inhalation of the carbon monoxide gas from the exhaust fumes leaking into the cabin of the car. The poor road network, numerous potholes, and traffic jam in most of roads in Nigeria could have exacerbated a leaky exhaust of the smoky second hand SUV car leading to the acute carbon monoxide poisoning.

  8. IL-6, a central acute-phase mediator, as an early biomarker for exposure to zinc-based metal fumes.

    Science.gov (United States)

    Baumann, R; Joraslafsky, S; Markert, A; Rack, I; Davatgarbenam, S; Kossack, V; Gerhards, B; Kraus, T; Brand, P; Gube, M

    2016-12-12

    -γ), cell counts] and the lung function parameters did not show any significant changes after exposure. Consistent with its role of the mediation of the acute-phase response, systemic increases of IL-6 after welding fume exposure peak at 10h before the increases of the acute-phase reactants CRP and SAA at 29h. IL-6 may represent a highly sensitive and early biomarker for the exposure to metal fumes containing zinc and copper. As IL-6, CRP and SAA are independent, strong risk markers for future cardiovascular diseases, these data may particularly be important for long-term welders with respect to their cardiovascular health. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Protective Effects of Lactobacillus plantarum CCFM8610 against Acute Cadmium Toxicity in Mice

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    Zhai, Qixiao; Wang, Gang; Zhao, Jianxin; Liu, Xiaoming; Zhang, Hao

    2013-01-01

    This study evaluated the protective effects of Lactobacillus plantarum CCFM8610, a selected probiotic with good cadmium binding capacity, against acute cadmium toxicity in mice. Ninety mice were divided into prevention and therapy groups. In the prevention groups, CCFM8610 was administered at 109 CFU once daily for 7 days, followed by a single oral dose of cadmium chloride at 1.8 mg cadmium for each mouse. In the therapy groups, the same dose of CCFM8610 was administered for 2 days after an identical single dose of cadmium exposure. Mice that received neither cadmium nor culture or that received cadmium alone served as negative and positive controls, respectively. The effects of both living and dead CCFM8610 on cadmium ion concentrations in feces, liver, and kidney were determined. Moreover, the alterations in reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and histopathology in the liver and kidney were investigated. The results showed that compared to the mice that received cadmium only, CCFM8610 treatment can effectively decrease intestinal cadmium absorption, reduce tissue cadmium accumulation, alleviate renal and hepatic oxidative stress, and ameliorate hepatic histopathological changes. Living CCFM8610 administered after cadmium exposure offered the most significant protection. Our results suggested that CCFM8610 is more effective against acute cadmium toxicity than a simple antioxidant treatment due to its special physiological functions and that it can be considered a new dietary therapeutic strategy against acute cadmium toxicity. PMID:23263961

  10. Reduction of Acute Inflammatory Effects of Fumed Silica Nanoparticles in the Lung by Adjusting Silanol Display through Calcination and Metal Doping.

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    Sun, Bingbing; Pokhrel, Suman; Dunphy, Darren R; Zhang, Haiyuan; Ji, Zhaoxia; Wang, Xiang; Wang, Meiying; Liao, Yu-Pei; Chang, Chong Hyun; Dong, Juyao; Li, Ruibin; Mädler, Lutz; Brinker, C Jeffrey; Nel, André E; Xia, Tian

    2015-09-22

    The production of pyrogenic (fumed) silica is increasing worldwide at a 7% annual growth rate, including expanded use in food, pharmaceuticals, and other industrial products. Synthetic amorphous silica, including fumed silica, has been generally recognized as safe for use in food products by the Food and Drug Administration. However, emerging evidence from experimental studies now suggests that fumed silica could be hazardous due to its siloxane ring structure, high silanol density, and "string-of-pearl-like" aggregate structure, which could combine to cause membrane disruption, generation of reactive oxygen species, pro-inflammatory effects, and liver fibrosis. Based on this structure-activity analysis (SAA), we investigated whether calcination and rehydration of fumed silica changes its hazard potential in the lung due to an effect on silanol density display. This analysis demonstrated that the accompanying change in surface reactivity could indeed impact cytokine production in macrophages and acute inflammation in the lung, in a manner that is dependent on siloxane ring reconstruction. Confirmation of this SAA in vivo, prompted us to consider safer design of fumed silica properties by titanium and aluminum doping (0-7%), using flame spray pyrolysis. Detailed characterization revealed that increased Ti and Al doping could reduce surface silanol density and expression of three-membered siloxane rings, leading to dose-dependent reduction in hydroxyl radical generation, membrane perturbation, potassium efflux, NLRP3 inflammasome activation, and cytotoxicity in THP-1 cells. The reduction of NLRP3 inflammasome activation was also confirmed in bone-marrow-derived macrophages. Ti doping, and to a lesser extent Al doping, also ameliorated acute pulmonary inflammation, demonstrating the possibility of a safer design approach for fumed silica, should that be required for specific use circumstances.

  11. Reviews of the environmental effects of pollutants: IV. Cadmium

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    Hammons, A.S.; Huff, J.E.; Braunstein, H.M.; Drury, J.S.; Shriner, C.R.; Lewis, E.B.; Whitfield, B.L.; Towill, L.E.

    1978-06-01

    This report is a comprehensive, multidisciplinary review of the health and environmental effects of cadmium and specific cadmium derivatives. More than 500 references are cited. The cadmium body burden in animals and humans results mainly from the diet. In the United States, the normal intake of cadmium for adult humans is estimated at about 50 ..mu..g per day. Tobacco smoke is a significant additional source of cadmium exposure. The kidneys and liver together contain about 50% of the total cadmium body burden. Acute cadmium poisoning is primarily an occupational problem, generally from inhalation of cadmium fumes or dusts. In the general population, incidents of acute poisoning by inhaled or ingested cadmium or its compounds are relatively rare. The kidney is the primary target organ for toxicity from prolonged low-level exposure to cadmium. No causal relationship has been established between cadmium exposure and human cancer, although a possible link between cadmium and prostate cancer has been indicated. Cadmium has been shown to be teratogenic in rats, hamsters, and mice, but no such effects have been proven in humans. Cadmium has been reported to increase the frequency of chromosomal aberrations in cultured Chinese hamster ovary cells and in human peripheral leukocytes. The major concern about environmental cadmium is the potential effects on the general population. There is no substantial evidence of hazard from current levels of cadmium in air, water, or food. However, because cadmium is a cumulative poison and because present intake provides a relatively small safety margin, there are adequate reasons for concern over possible future increases in background levels.

  12. Reviews of the environmental effects of pollutants: IV. Cadmium

    International Nuclear Information System (INIS)

    Hammons, A.S.; Huff, J.E.; Braunstein, H.M.; Drury, J.S.; Shriner, C.R.; Lewis, E.B.; Whitfield, B.L.; Towill, L.E.

    1978-06-01

    This report is a comprehensive, multidisciplinary review of the health and environmental effects of cadmium and specific cadmium derivatives. More than 500 references are cited. The cadmium body burden in animals and humans results mainly from the diet. In the United States, the normal intake of cadmium for adult humans is estimated at about 50 μg per day. Tobacco smoke is a significant additional source of cadmium exposure. The kidneys and liver together contain about 50% of the total cadmium body burden. Acute cadmium poisoning is primarily an occupational problem, generally from inhalation of cadmium fumes or dusts. In the general population, incidents of acute poisoning by inhaled or ingested cadmium or its compounds are relatively rare. The kidney is the primary target organ for toxicity from prolonged low-level exposure to cadmium. No causal relationship has been established between cadmium exposure and human cancer, although a possible link between cadmium and prostate cancer has been indicated. Cadmium has been shown to be teratogenic in rats, hamsters, and mice, but no such effects have been proven in humans. Cadmium has been reported to increase the frequency of chromosomal aberrations in cultured Chinese hamster ovary cells and in human peripheral leukocytes. The major concern about environmental cadmium is the potential effects on the general population. There is no substantial evidence of hazard from current levels of cadmium in air, water, or food. However, because cadmium is a cumulative poison and because present intake provides a relatively small safety margin, there are adequate reasons for concern over possible future increases in background levels

  13. Cadmium

    NARCIS (Netherlands)

    Meulenbelt, Jan

    2017-01-01

    Together with zinc and mercury, cadmium belongs to group IIb of the periodic table. It can be found in rocks, soil, water, coal, zinc ore, lead ore, and copper ore. In the environment, cadmium is present predominantly as the oxide or as the chloride, sulfide, or sulfate salt. It has no recognizable

  14. Nrf2 activation prevents cadmium-induced acute liver injury

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    Wu, Kai C. [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Liu, Jie J. [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Klaassen, Curtis D., E-mail: cklaasse@kumc.edu [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States)

    2012-08-15

    Oxidative stress plays an important role in cadmium-induced liver injury. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that up-regulates cytoprotective genes in response to oxidative stress. To investigate the role of Nrf2 in cadmium-induced hepatotoxicity, Nrf2-null mice, wild-type mice, kelch-like ECH-associated protein 1-knockdown (Keap1-KD) mice with enhanced Nrf2, and Keap1-hepatocyte knockout (Keap1-HKO) mice with maximum Nrf2 activation were treated with cadmium chloride (3.5 mg Cd/kg, i.p.). Blood and liver samples were collected 8 h thereafter. Cadmium increased serum alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activities, and caused extensive hepatic hemorrhage and necrosis in the Nrf2-null mice. In contrast, Nrf2-enhanced mice had lower serum ALT and LDH activities and less morphological alternations in the livers than wild-type mice. H{sub 2}DCFDA (2′,7′-dichlorodihydrofluoresein diacetate) staining of primary hepatocytes isolated from the four genotypes of mice indicated that oxidative stress was higher in Nrf2-null cells, and lower in Nrf2-enhanced cells than in wild-type cells. To further investigate the mechanism of the protective effect of Nrf2, mRNA of metallothionein (MT) and other cytoprotective genes were determined. Cadmium markedly induced MT-1 and MT-2 in livers of all four genotypes of mice. In contrast, genes involved in glutathione synthesis and reducing reactive oxygen species, including glutamate-cysteine ligase (Gclc), glutathione peroxidase-2 (Gpx2), and sulfiredoxin-1 (Srxn-1) were only induced in Nrf2-enhanced mice, but not in Nrf2-null mice. In conclusion, the present study shows that Nrf2 activation prevents cadmium-induced oxidative stress and liver injury through induction of genes involved in antioxidant defense rather than genes that scavenge Cd. -- Highlights: ► Cadmium caused extensive hepatic hemorrhage and necrosis in Nrf2-null mice. ► Keap1-KD and Keap1-HKO mice

  15. Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides)

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    Mehinto, Alvine C., E-mail: alvinam@sccwrp.org [Southern California Coastal Water Research Project, Costa Mesa, CA 92626 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Prucha, Melinda S. [Department of Human Genetics, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Colli-Dula, Reyna C.; Kroll, Kevin J.; Lavelle, Candice M.; Barber, David S. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Vulpe, Christopher D. [Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720 (United States); Denslow, Nancy D. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States)

    2014-07-01

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

  16. Histopathological alterations in the edible snail, Babylonia areolata (spotted babylon), in acute and subchronic cadmium poisoning.

    Science.gov (United States)

    Tanhan, P; Sretarugsa, P; Pokethitiyook, P; Kruatrachue, M; Upatham, E S

    2005-04-01

    Histopathological alterations in 6- to 8-month-old juvenile spotted babylon, Babylonia areolata, from acute and subchronic cadmium exposure were studied by light microscopy. The 96-h LC(50) value of cadmium for B. areolata was found to be 3.35 mg/L, and the maximum acceptable toxicant concentration (MATC) was 1.6 mg/L. Snails were exposed to 3.35 and 0.08 mg/L (5% of MATC) of cadmium for 96 h and 90 days, respectively. After exposure the gill, the organs of the digestive system (proboscis, esophagus, stomach, digestive gland, and rectum), and the foot were analyzed for cadmium accumulation. The results showed that most digestive organs had a high affinity for cadmium. The main target organ was the stomach, which could accumulate on average 1192.18 microg/g dry weight of cadmium. Cadmium was shown to accumulate to a lesser extent in the digestive gland, gill, rectum, esophagus, proboscis, and foot. Histopathological alterations were observed in the gill and digestive organs (proboscis, esophagus, stomach, and rectum). The study showed that the stomach and gill were the primary target organs of both acute and subchronic exposure. Gill alterations included increased size of mucous vacuoles, reduced length of cilia, dilation and pyknosis of nuclei, thickening of basal lamina, and accumulation of hemocytes. The epithelial lining of the digestive tract showed similar alterations such as increased size of mucous vacuoles, reduced length of cilia, and dilation of nuclei. In addition, fragmentation of the muscle sheath was observed.

  17. Short Communication Acute toxicity of cadmium against catfish ...

    African Journals Online (AJOL)

    The upper and lower confidence limits and slope functions were calculated. The LC50 values for Cadmium Chloride at 24, 48, 72 and 96 h are 620.34, 414.59, 384.88 and 360.50 mg/l, respectively. The upper confidence limits were 645.59, 433.27, 394.72 and 380.32 mg/l for 24, 48, 72 and 96 h and lower confidence limits ...

  18. Visibility in sodium fume

    International Nuclear Information System (INIS)

    Hughes, G.W.; Anderson, N.R.

    1971-01-01

    The appearance of sodium fume of unknown concentration and the effects of short term exposure on unprotected workers is described. The molecular extinction coefficient of sodium fume is calculated from which light transmission data, and a rapid method for the estimation of the fume concentration is proposed. (author)

  19. Histopathological alterations of white seabass, Lates calcarifer, in acute and subchronic cadmium exposure

    International Nuclear Information System (INIS)

    Thophon, S.; Kruatrachue, M.; Upatham, E.S.; Pokethitiyook, P.; Sahaphong, S.; Jaritkhuan, S.

    2003-01-01

    White seabass responded differently to cadmium at chronic and subchronic levels. - Histopathological alterations to white seabass, Lates calcarifer aged 3 months in acute and subchronic cadmium exposure were studied by light and scanning electron microscopy. The 96-h LC 50 values of cadmium to L. calcarifer was found to be 20.12±0.61 mg/l and the maximum acceptable toxicant concentration (MATC) was 7.79 mg/l. Fish were exposed to 10 and 0.8 mg/l of Cd (as CdCl 2 H 2 O) for 96 h and 90 days, respectively. The study showed that gill lamellae and kidney tubules were the primary target organs for the acute toxic effect of cadmium while in the subchronic exposure, the toxic effect to gills was less than that of kidney and liver. Gill alterations included edema of the epithelial cells with the breakdown of pillar cell system, aneurisms with some ruptures, hypertrophy and hyperplasia of epithelial and chloride cells. The liver showed blood congestion in sinusoids and hydropic swelling of hepatocytes, vacuolation and dark granule accumulation. Lipid droplets and glycogen content were observed in hepatocytes at the second and third month of subchronic exposure. The kidney showed hydropic swelling of tubular cell vacuolation and numerous dark granule accumulation in many tubules. Tubular degeneration and necrosis were seen in some areas

  20. Test for Acute Toxicity of Copper, Cadmium, and Mercury in Five Marine Species

    OpenAIRE

    PRATO, Ermelinda; BIANDOLINO, Francesca; SCARDICCHIO, Christian

    2006-01-01

    : The acute toxicity of copper (Cu), cadmium (Cd), and mercury (Hg) to the marine invertebrates Gammarus aequicauda, Corophium insidiosum, Idotea baltica, Sphaeroma serratum, and Mytilus galloprovincialis were evaluated by static bioassays and calculation of the LC50 (lethality concentration for 50%). Hg was more toxic to Gammarus aequicauda, Corophium insidiosum, Idotea baltica, Sphaeroma serratum, and Mytilus galloprovincialis than Cu and Cd. Cu was the least toxic of the metals tested.

  1. Effect of Acute Toxicity of Cadmium in Mice Kidney Cells

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    Masoomeh Masoomi Karimi

    2012-11-01

    Full Text Available Background: Cadmium is one of the most toxic heavy metals in our environment having a very strong ability to accumulate in body organs, especially in kidney. The present study was done to determine the genotoxicity and cytotoxicity in kidneys of rats exposed to cadmium. Methods: Male rats (n=30, kept in standard conditions were used in this study. The animals were randomly divided into 2 groups (control and treatment. The treatment group was intraperitoneally injected with Cd (300µm/kg at hours 0, 6, 12, 24, 48. Twenty four hours after the last injection, the rats were sacrificed and their kidneys were obtained. Then oxidative stress markers, malondialdehide (MDA, glutathione (GSH, and superoxide dismutase (SOD, were assayed in homogenized kidney for studying their cytotoxicity. For genotoxicity and DNA damage studies, Comet assay was run on isolated kidney cells. Data analysis was done by t-test and ANOVA using SPSS software version 15. Results: MDA and GSH concentrations in normal and Cd exposed kidney cells were 287.01±37.30nmol/g.pr and 15.61±3.89µmol/g.pr and 609.24±87.87nmol/g.pr and 28.52±5.22µmol/g.pr, respectively. In addition, SOD activity in normal and Cd exposed kidney cells were 77.75±4.12 and 218.91±5.40 U/mg.pr, respectively. Comet assay results (content comet length, tail length, and head diameter showed DNA breakage in the treatment group that was stimulated by Cd which was not seen in the control group. Conclusion: The results demonstrated the genotoxicity effect of Cd on kidney cells as well as the ability of Cd to producing cytotoxicity.

  2. Murine strain differences and the effects of zinc on cadmium concentrations in tissues after acute cadmium exposure

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    King, L.M. [ARS USDA, Germplasm and Gamete Physiology Lab., Beltsville, MD (United States); Anderson, M.B. [Dept. of Anatomy, Tulane Univ. School of Medicine, New Orleans, LA (United States); Sikka, S.C. [Dept. of Urology, Tulane Univ. School of Medicine, New Orleans, LA (United States); George, W.J. [Dept. of Pharmacology, Tulane Univ. School of Medicine, New Orleans, LA (United States)

    1998-10-01

    The role of strain differences in cadmium tissue distribution was studied using sensitive (129/J) and resistant (A/J) mice. These murine strains have previously been shown to differ in their susceptibility to cadmium-induced testicular toxicity. Cadmium concentration was measured in testis, epididymis, seminal vesicle, liver, and kidney at 24 h after cadmium chloride exposure (4, 10, and 20 {mu}mol/kg CdCl{sub 2}). The 129/J mice exhibited a significant increase in cadmium concentration in testis, epididymis, and seminal vesicle at all cadmium doses used, compared to A/J mice. However, cadmium concentrations in liver and kidney were not different between the strains, at any dose, indicating that cadmium uptake is similar in these organs at 24 h. These murine strains demonstrate similar hepatic and renal cadmium uptake but significantly different cadmium accumulation in the reproductive organs at 24 h. The mechanism of the protective effect of zinc on cadmium toxicity was studied by assessing the impact of zinc acetate (ZnAc) treatment on cadmium concentrations in 129/J mice after 24 h. Zinc pretreatment (250 {mu}mol/kg ZnAc), given 24 h prior to 20 {mu}mol/kg CdCl{sub 2} administration, significantly decreased the amount of cadmium in the testis, epididymis, and seminal vesicle of 129/J mice, and significantly increased the cadmium content of the liver after 24 h. Cadmium levels in the kidney were unaffected at this time. Zinc pretreatment also prevented the cadmium-induced decrease in testicular sperm concentration and epididymal sperm motility seen in 129/J mice. These findings suggest that the differences in the two murine strains may be attributed partly to the differential accumulation of cadmium in murine gonads. This may be caused by strain differences in the specificity of cadmium transport mechanisms. The protective role of zinc in cadmium-induced testicular toxicity in the sensitive strain may be due to an interference in the cadmium uptake by susceptible

  3. The hepatoprotective effect of putrescine against cadmium-induced acute liver injury

    Energy Technology Data Exchange (ETDEWEB)

    Tzirogiannis, Konstantinos N.; Panoutsopoulos, Georgios I.; Papadimas, George K.; Kondyli, Vasiliki G.; Kourentzi, Kalliopi T.; Hereti, Rosa I.; Mykoniatis, Michael G. [Department of Experimental Pharmacology, Medical School, Athens University, 75 Mikras Asias St., 115 27, Athens (Greece); Demonakou, Maria D. [Histopathology Laboratory, Sismanoglion G.D. Hospital, Sismanogliou 1, Marousi 151 27, Attiki (Greece)

    2004-06-01

    The hepatoprotective effect of putrescine against cadmium liver injury was investigated. Male Wistar rats were injected with a dose of cadmium (6.5 mg CdCl{sub 2}/kg bodyweight, intraperitoneally). Normal saline (group I) or putrescine (300 {mu}mol/kg bodyweight; group II) were injected 2, 5 and 8 h later. A number of animals of both groups were killed 0, 12, 16, 24, 48 or 60 h after cadmium intoxication. Liver tissue was histologically assessed for necrosis, apoptosis, peliosis, mitoses, and inflammatory infiltration. Apoptosis was also quantified by the TUNEL assay for hepatocytes and nonparenchymal liver cells. The discrimination between hepatic cell subpopulations was achieved histochemically. The mitotic index in hematoxylin-eosin-stained sections and by the immunochemical detection of Ki67 nuclear antigen, {sup 3}H-thymidine incorporation into hepatic DNA, and hepatic thymidine kinase activity were all used as indices of liver regeneration. Both hepatocyte apoptosis and liver necrosis evolved in a biphasic temporal pattern. Nonparenchymal cell apoptosis and peliosis hepatis evolved in a monophasic pattern and were correlated closely. Putrescine administration totally reversed liver necrosis and hepatocyte apoptosis. The time profile of nonparenchymal apoptosis was altered and peliosis hepatis was also totally attenuated. In conclusion, putrescine protected hepatocytes and modulated the mechanism of cadmium-induced acute hepatotoxicity. (orig.)

  4. Role of nitric oxide synthase inhibition in the acute hypertensive response to intracerebroventricular cadmium

    Science.gov (United States)

    Demontis, Maria Piera; Varoni, Maria Vittoria; Volpe, Anna Rita; Emanueli, Costanza; Madeddu, Paolo

    1998-01-01

    In the rat, intracerebroventricular (i.c.v.) injection of cadmium, a pollutant with long biological half-life, causes a sustained increase in blood pressure at doses that are ineffective by peripheral route. Since cadmium inhibits calcium-calmodulin constitutive nitric oxide (NO) synthase in cytosolic preparations of rat brain, this mechanism may be responsible for the acute pressor action of this heavy metal.To test this possibility, we evaluated the effect of i.c.v. injection of 88 nmol cadmium in normotensive unanaesthetized Wistar rats, which were i.c.v. pre-treated with: (1) saline (control), (2) L-arginine (L-Arg), to increase the availability of substrate for NO biosynthesis, (3) D-arginine (D-Arg), (4) 3-[4-morpholinyl]-sydnonimine-hydrochloride (SIN-1), an NO donor, or (5) CaCl2, a cofactor of brain calcium-calmodulin-dependent cNOSI. In additional experiments, the levels of L-citrulline (the stable equimolar product derived from enzymatic cleavage of L-Arg by NO synthase) were determined in the brain of vehicle- or cadmium-treated rats.The pressor response to cadmium reached its nadir at 5 min (43±4 mmHg) and lasted over 20 min in controls. L-Citrulline/protein content was reduced from 35 up to 50% in the cerebral cortex, pons, hippocampus, striatus, hypothalamus (P<0.01) of cadmium-treated rats compared with controls. Central injection of NG nitro-L-arginine-methylester (L-NAME) also reduced the levels of L-citrulline in the brain.Both the magnitude and duration of the response were attenuated by 1.21 and 2.42 μmol SIN-1 (32±3 and 15±4 mmHg, P<0.05), or 1 μmol CaCl2 (6±4 mmHg, P<0.05). Selectivity of action exerted by SIN-1 was confirmed by the use of another NO donor, S-nitroso-N-acetyl-penicillamine (SNAP). Both L-Arg and D-Arg caused a mild but significant attenuation in the main phase of the pressor response evoked by cadmium. However, only L-Arg reduced the magnitude of the delayed, pressor response. Despite their similarity in

  5. Protective effects of synbiotic diets of Bacillus coagulans, Lactobacillus plantarum and inulin against acute cadmium toxicity in rats.

    Science.gov (United States)

    Jafarpour, Dornoush; Shekarforoush, Seyed Shahram; Ghaisari, Hamid Reza; Nazifi, Saeed; Sajedianfard, Javad; Eskandari, Mohammad Hadi

    2017-06-05

    Cadmium is a heavy metal that causes oxidative stress and has toxic effects in humans. The aim of this study was to investigate the influence of two probiotics along with a prebiotic in preventing the toxic effects of cadmium in rats. Twenty-four male Wistar rats were randomly divided into four groups namely control, cadmium only, cadmium along with Lactobacillus plantarum (1 × 109 CFU/day) and inulin (5% of feedstuff) and cadmium along with Bacillus coagulans (1 × 109 spore/day) and inulin (5% of feedstuff). Cadmium treated groups received 200 μg/rat/day CdCl2 administered by gavage. During the 42-day experimental period, they were weighed weekly. For evaluation of changes in oxidative stress, the levels of some biochemicals and enzymes of serum including SOD, GPX, MDA, AST, ALT, total bilirubin, BUN and creatinine, and also SOD level of livers were measured at day 21 and 42 of treatment. The cadmium content of kidney and liver was determined by using atomic absorption mass spectrophotometry. Data were analyzed using analysis of variance (ANOVA) followed by Duncan's post hoc test. Treatment of cadmium induced rats with synbiotic diets significantly improved the liver enzymes and biochemical parameters that decreased AST, ALT, total bilirubin, BUN and metal accumulation in the liver and kidney and increased body weight, serum and liver SOD values in comparison with the cadmium-treated group. No significant differences were observed with MDA and GP X values between all groups (p > 0.05). This study showed that synbiotic diets containing probiotics (L. plantarum and B. coagulans) in combination with the prebiotic (inulin) can reduce the level of cadmium in the liver and kidney, preventing their damage and recover antioxidant enzymes in acute cadmium poisoning in rat.

  6. Cadmium exposure: Health hazards of silver cottage industry in developing countries

    OpenAIRE

    Sethi, P. K.; Khandelwal, Dinesh; Sethi, Nitin

    2006-01-01

    In countries such as India, the silver jewelry industry is an important cottage industry. Silver is mixed with cadmium and then used to make silver jewelry. During this process there is a formation of cadmium fumes, and the workers inhale the fumes. Cadmium is a neurotoxic and nephrotoxic heavy metal, and there are no national policies to prevent exposure to such chemicals. We will present a case of cadmium induced peripheral neuropathy, nephropathy, and decreased bone density.

  7. Aquatic Life Criteria - Cadmium

    Science.gov (United States)

    Documents pertaining to 2016 Acute and Chronic Aquatic Life Ambient Water Quality Criteria for Cadmium (Freshwater, Estuarine/marine). These documents contain the safe levels of Cadmium in water that should protect to the majority of species.

  8. Aquatic Life Criteria - Cadmium Documents

    Science.gov (United States)

    Documents pertaining to 2016 Acute and Chronic Aquatic Life Ambient Water Quality Criteria for Cadmium (Freshwater, Estuarine/marine). These documents contain the safe levels of Cadmium in water that should protect the majority of species.

  9. Influence of acclimation and exposure temperature on the acute toxicity of cadmium to the freshwater snail Potamopyrgus antipodarum (Hydrobiidae)

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, V.; Forbes, V.E.; Depledge, M.H. (Odense Univ. (Denmark). Ecotoxicology Group)

    1994-09-01

    Forty-eight-hour acute toxicity tests were performed to determine the influence of acclimation temperature (5, 15, and 20 C) and exposure temperature (5, 15, and 20 C) on the toxicity of cadmium to the freshwater gastropod Potamopyrgus antipodarum. Mortality varied with cadmium concentration and treatment conditions, but did not conform to conventional sigmoid concentration-response relationships. Because the shapes of the concentration-response curves were treatment dependent, a nontraditional approach for data analysis was employed. Regardless of acclimation temperature, mortality increased with increasing exposure temperature, and at all exposure temperatures snails acclimated at 15 C were most susceptible to cadmium toxicity. Estimated LC50 values were within 1 to 4 mg Cd/L. Although the shapes of the concentration-response curves were different for each treatment, the slopes were generally quite steep, indicating a uniform response for the whole population. At a given Cd concentration, acclimation temperature and exposure temperature accounted for 57 and 40%, respectively, of the variation in mortality, and LC50s changed by a factor of four. The results indicate that changes in environmental variables can alter both the degree of response and the response distribution of a population, and that past as well as prevailing environmental conditions can influence organismic responses to toxicants.

  10. Time-course of cadmium-induced acute hepatotoxicity in the rat liver: the role of apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Tzirogiannis, Konstantinos N.; Panoutsopoulos, Georgios I.; Hereti, Rosa I.; Alexandropoulou, Katerina N.; Basayannis, Aristidis C.; Mykoniatis, Michael G. [Department of Experimental Pharmacology, Medical School, Athens University, 75 Mikras Asias St., 115 27, Athens (Greece); Demonakou, Maria D. [Histopathology Laboratory, Sismanoglion G.D. Hospital, Sismanogliou 1, Marousi, Attiki 151 27 (Greece)

    2003-12-01

    Exposure to toxic metals and pollutants is a major environmental problem. Cadmium is a metal causing acute hepatic injury but the mechanism of this phenomenon is poorly understood. In the present study, we investigated the mechanism and time-course of cadmium-induced liver injury in rats, with emphasis being placed on apoptosis in parenchymal and nonparenchymal liver cells. Cadmium (3.5 mg/kg body weight) was injected intraperitoneally and the rats were killed 0, 9, 12, 16, 24, 48 and 60 h later. The extent of liver injury was evaluated for necrosis, apoptosis, peliosis, mitoses and inflammatory infiltration in hematoxylin-eosin-stained liver sections, and by assaying serum enzyme activities. The number of cells that died via apoptosis was quantified by TUNEL assay. The identification of nonparenchymal liver cells and activated Kupffer cells was performed histochemically. Liver regeneration was evaluated by assaying the activity of liver thymidine kinase and by the rate of {sup 3}H-thymidine incorporation into DNA. Both cadmium-induced necrotic cell death and parenchymal cell apoptosis showed a biphasic elevation at 12 and 48 h and peaked at 48 and 12 h, respectively. Nonparenchymal cell apoptosis peaked at 48 h. Peliosis hepatis, another characteristic form of liver injury, was first observed at 16 h and, at all time points, closely correlated with the apoptotic index of nonparenchymal liver cells, where the lesion was also maximial at 48 h. Kupffer cell activation and neutrophil infiltration were minimal for all time points examined. Based on thymidine kinase activity, liver regeneration was found to discern a classic biphasic peak pattern at 12 and 48 h. It was very interesting to observe that cadmium-induced liver injury did not involve inflammation at any time point. Apoptosis seems to be a major mechanism for the removal of damaged cells, and constitutes the major type of cell death in nonparenchymal liver cells. Apoptosis of nonparenchymal cells is the basis

  11. 42 CFR 84.1146 - Lead fume test for dust, fume, and mist respirators; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1146 Lead fume test for dust, fume, and mist... fume, calculated as lead (Pb), per cubic meter of air. (d) The fume will be generated by impinging an...

  12. Preliminary Studies of Acute Cadmium Administration Effects on the Calcium-Activated Potassium (SKCa and BKCa) Channels and Na+/K+-ATPase Activity in Isolated Aortic Rings of Rats.

    Science.gov (United States)

    Vassallo, Dalton V; Almenara, Camila C P; Broseghini-Filho, Gilson Brás; Teixeira, Ariane Calazans; da Silva, David Chaves F; Angeli, Jhuli K; Padilha, Alessandra S

    2017-09-13

    Cadmium is an environmental pollutant closely linked with cardiovascular diseases that seems to involve endothelium dysfunction and reduced nitric oxide (NO) bioavailability. Knowing that NO causes dilatation through the activation of potassium channels and Na + /K + -ATPase, we aimed to determine whether acute cadmium administration (10 μM) alters the participation of K + channels, voltage-activated calcium channel, and Na + /K + -ATPase activity in vascular function of isolated aortic rings of rats. Cadmium did not modify the acetylcholine-induced relaxation. After L-NAME addition, the relaxation induced by acetylcholine was abolished in presence or absence of cadmium, suggesting that acutely, this metal did not change NO release. However, tetraethylammonium (a nonselective K + channels blocker) reduced acetylcholine-induced relaxation but this effect was lower in the preparations with cadmium, suggesting a decrease of K + channels function in acetylcholine response after cadmium incubation. Apamin (a selective blocker of small Ca 2+ -activated K + channels-SK Ca ), iberiotoxin (a selective blocker of large-conductance Ca 2+ -activated K + channels-BK Ca ), and verapamil (a blocker of calcium channel) reduced the endothelium-dependent relaxation only in the absence of cadmium. Finally, cadmium decreases Na + /K + -ATPase activity. Our results provide evidence that the cadmium acute incubation unaffected the calcium-activated potassium channels (SK Ca and BK Ca ) and voltage-calcium channels on the acetylcholine vasodilatation. In addition, acute cadmium incubation seems to reduce the Na + /K + -ATPase activity.

  13. Evaluation of serum levels of cadmium and Lead in occupationally ...

    African Journals Online (AJOL)

    Cadmium and Lead are extremely toxic metals found in industrial workplaces. They are also found in some industrial paints and may represent hazards when sprayed.Exposure to Cadmium fumes may cause flu-like symptoms including chills, fever and muscle ache sometimes reffered to as "the cadium blues." Occupational ...

  14. Cytochemical study of carp neutrophil granulocytes after acute exposure to cadmium

    Czech Academy of Sciences Publication Activity Database

    Drastichová, J.; Švestková, E.; Lusková, Věra; Svobodová, Z.

    2005-01-01

    Roč. 21, č. 3 (2005), s. 215-219 ISSN 0175-8659 Institutional research plan: CEZ:AV0Z60930519 Keywords : peripheral- blood leukocytes * cadmium * common carp Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.563, year: 2005

  15. 222-S LABORATORY FUME HOOD TESTING STUDY

    International Nuclear Information System (INIS)

    RUELAS, B.H.

    2007-01-01

    The 222-S Laboratory contains 155 active fume hoods that are used to support analytical work with radioactive and/or toxic materials. The performance of a fume hood was brought into question after employees detected odors in the work area while mixing chemicals within the subject fume hood. Following the event, testing of the fume hood was conducted to assess the performance of the fume hood. Based on observations from the testing, it was deemed appropriate to conduct performance evaluations of other fume hoods within the laboratory

  16. Oral cadmium chloride intoxication in mice

    DEFF Research Database (Denmark)

    Andersen, O; Nielsen, J B; Svendsen, P

    1988-01-01

    Diethyldithiocarbamate (DDC) is known to alleviate acute toxicity due to injection of cadmium salts. However, when cadmium chloride was administered by the oral route, DDC enhanced rather than alleviated the acute toxicity; both oral and intraperitoneal (i.p.) administration of DDC had this effect....... Thus, orally administered DDC enhanced cadmium-induced duodenal and ileal tissue damage and inhibition of peristalsis, as indicated by an increased intestinal transit time. At low cadmium doses, the whole-body retention of cadmium was increased by oral DDC administration. Intraperitoneally administered...... DDC increased cadmium-induced acute mortality and testicular necrosis, and it enhanced cadmium-induced reduction of intestinal motility and increased the whole-body retention of cadmium, indicating increased intestinal cadmium absorption. Also, DDC changed the organ distribution of absorbed cadmium...

  17. Comparative acute toxicity of gallium(III), antimony(III), indium(III), cadmium(II), and copper(II) on freshwater swamp shrimp (Macrobrachium nipponense).

    Science.gov (United States)

    Yang, Jen-Lee

    2014-04-01

    Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.

  18. Occupational rhinitis due to steel welding fumes.

    Science.gov (United States)

    Castano, Roberto; Suarthana, Eva

    2014-12-01

    Exposure to welding fumes is a recognized respiratory hazard. Occupational asthma but not occupational rhinitis has been documented in workers exposed to steel welding fumes. We report a 26-year-old male with work-related rhinitis symptoms as well as lower airways symptoms suggestive of occupational asthma and metal fume fever associated with exposure to steel welding fumes. The diagnosis of occupational rhinitis was confirmed by specific inhalation challenge. © 2014 Wiley Periodicals, Inc.

  19. Effect of acute exposure to cadmium on the expression of heat-shock and hormone-nuclear receptor genes in the aquatic midge Chironomus riparius

    Energy Technology Data Exchange (ETDEWEB)

    Planello, R.; Martinez-Guitarte, J.L. [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain); Morcillo, G., E-mail: gmorcillo@ccia.uned.es [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain)

    2010-03-01

    Cadmium is a widespread and highly toxic pollutant of particular ecotoxicological relevance for aquatic ecosystems where it accumulates. To identify biomarkers for ecotoxicity monitoring, the effect of cadmium on the expression of different genes related to the stress response as well as to the ecdysone hormone-signalling pathway was studied in the aquatic larvae of Chironomus riparius (Diptera, Chironomidae), a standard test organism in aquatic toxicology testing. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was used to evaluate the effects of acute and short-term cadmium exposures (10 mM CdCl{sub 2}, 12 h and 24 h) on the expression of hsp70, hsc70, hsp90 and hsp40 genes, as well as on that of the ecdysone hormonal-receptor genes (EcR and usp). A significant 3-fold increase in the level of hsp70 gene transcripts was induced by the treatment, whereas neither the other stress genes tested (hsp90 and hsp40) nor the constitutive form of hsp70, hsc70, was affected in the larvae exposed to cadmium. These results show that hsp70 is differentially activated to other environmentally regulated heat-shock genes, and constitutes a biomarker of exposure to this toxic metal. In addition, we also found that cadmium is able to alter the expression of the ecdysone receptor gene (EcR), whose mRNA level is significantly increased whereas usp levels remained unaltered. This finding, evidenced for the first time in invertebrates, supports the view that cadmium has the ability to mimic the effect of the hormone by the activation of the ecdysone nuclear receptor, which may partly explain the endocrine disruption capability that has been previously suggested for this toxic metal. Our research adds to the growing evidence implicating heavy metals, and cadmium in particular, as potential endocrine disruptive agents and may have significant implications for ecological risk assessment of endocrine-disrupting compounds in invertebrates.

  20. Effect of acute exposure to cadmium on the expression of heat-shock and hormone-nuclear receptor genes in the aquatic midge Chironomus riparius

    International Nuclear Information System (INIS)

    Planello, R.; Martinez-Guitarte, J.L.; Morcillo, G.

    2010-01-01

    Cadmium is a widespread and highly toxic pollutant of particular ecotoxicological relevance for aquatic ecosystems where it accumulates. To identify biomarkers for ecotoxicity monitoring, the effect of cadmium on the expression of different genes related to the stress response as well as to the ecdysone hormone-signalling pathway was studied in the aquatic larvae of Chironomus riparius (Diptera, Chironomidae), a standard test organism in aquatic toxicology testing. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was used to evaluate the effects of acute and short-term cadmium exposures (10 mM CdCl 2 , 12 h and 24 h) on the expression of hsp70, hsc70, hsp90 and hsp40 genes, as well as on that of the ecdysone hormonal-receptor genes (EcR and usp). A significant 3-fold increase in the level of hsp70 gene transcripts was induced by the treatment, whereas neither the other stress genes tested (hsp90 and hsp40) nor the constitutive form of hsp70, hsc70, was affected in the larvae exposed to cadmium. These results show that hsp70 is differentially activated to other environmentally regulated heat-shock genes, and constitutes a biomarker of exposure to this toxic metal. In addition, we also found that cadmium is able to alter the expression of the ecdysone receptor gene (EcR), whose mRNA level is significantly increased whereas usp levels remained unaltered. This finding, evidenced for the first time in invertebrates, supports the view that cadmium has the ability to mimic the effect of the hormone by the activation of the ecdysone nuclear receptor, which may partly explain the endocrine disruption capability that has been previously suggested for this toxic metal. Our research adds to the growing evidence implicating heavy metals, and cadmium in particular, as potential endocrine disruptive agents and may have significant implications for ecological risk assessment of endocrine-disrupting compounds in invertebrates.

  1. Nuclear myocardial perfusion imaging with a cadmium-telluride semiconductor detector gamma camera in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    Fukushima, Yoshimitsu; Kumita, Shin-ichiro; Kawaguchi, Tsuneaki; Maruyama, Takatoshi; Kawasaki, Yoshiyuki; Shinkai, Yasuhiro

    2014-01-01

    Since myocardial perfusion imaging (MPI) with conventional sodium iodine (NaI) device has low spatial resolution, there have been some cases in which small structures such as non-transmural myocardial infarction could not be properly detected. The purpose of this study was to evaluate potential usefulness of cadmium-telluride (CdTe) semiconductor detector-based high spatial resolution gamma cameras in detecting myocardial infarction sites, especially non-transmural infarction. A total of 38 patients (mean age ± SD: 64 ± 21 year) who were clinically diagnosed with acute myocardial infarction were included. Twenty-eight cases of them were with ST segment elevation myocardial infarction (STEMI) and 10 cases with non-ST segment elevation myocardial infarction (NSTEMI). In all patients, myocardial perfusion single photon emission computed tomography images were acquired with Infinia (NaI device) and R1-M (CdTe device), and the images were compared concerning the detectability of acute myocardial infarction sites. The detection rates of the myocardial infarction site in cases with STEMI were 100% both by NaI and CdTe images. In cases with NSTEMI, detection rate by NaI images was 50%, while that of CdTe images was 100% (p=0.033). The summed rest score (SRS) value derived from CdTe images was significantly higher than that from NaI images in cases with STEMI [NaI images: 12 (7-18) versus CdTe images: 14 (9-20)] (p < 0.001). SRS derived from CdTe images was significantly higher than that derived from NaI images in cases with NSTEMI [NaI images: 2 (0-5) versus CdTe images: 6 (6-8)] (p=0.006). These results indicate that MPI using CdTe-semiconductor device will provide a much more accurate assessment of acute myocardial infarction in comparison to current methods. (author)

  2. Acute toxicities of copper, cadmium and Cu: Cd mixture to larvae of the shrimp Penaeus Penicillatus

    Science.gov (United States)

    Munshi, A. B.; Su, Yong-Quan; Li, Shao-Jing

    1996-06-01

    This study showed lethal concentrations (LC) of copper for Peneaus penicillatus at various stages of its life cycle were 1000 μg/L for nauplii, 1000 μg/L for Zoea I, 2000 vg/L for Zoea II, 2500 μg/L for Zoea III, 3000 μg/L for Mysis I, II and III and that for almost 100% mortality for postlarvae was 3000 μg/L. For cadmium LC were 100 μg/L for nauplii, 500 μg/L for Zoea I, 1000 μg/L for Zoea II, 2000 μg/L for Zoea III, 2500 μg/L for Mysis I and 3500 μg/L for Mysis II, III and postlarvae. For mixture of both metals, LC were 400 μg/L for nauplii, 1000 μg/L for Zoea I, 2000 μg/L for Zoea II and 3000 μg/L for Mysis I, II, III and post larvae.

  3. Copper, but not cadmium, is acutely toxic for trout hepatocytes: short-term effects on energetics and ion homeostasis

    International Nuclear Information System (INIS)

    Manzl, Claudia; Ebner, Hannes; Koeck, Guenter; Dallinger, Reinhard; Krumschnabel, Gerhard

    2003-01-01

    The toxic effects of cadmium (Cd) and copper (Cu) on cellular energy metabolism and ion homeostasis were investigated in hepatocytes from the rainbow trout, Oncorhynchus mykiss. The metal content of cells did not increase during incubation with Cu, whereas a dose-dependent increase was seen with Cd. Cell viability was unaffected in the presence of 100 μM Cd and 10 μM Cu but was significantly reduced after 30 min of exposure to 100 μM Cu, both in the presence and absence of extracellular calcium. Oxygen consumption (VO 2 ) was not affected by 100 μM Cd or 10 μM Cu, whereas 100 μM Cu caused a significant and calcium-dependent increase of VO 2 . Lactate production and basal glucose release were not altered by either of the metals. However, the epinephrine-stimulated rate of glucose release was significantly reduced after 2 h of incubation with 100 μM Cu. Hepatocytes exposed to Cd showed only a marginal increase of intracellular free calcium (Ca i 2+ ), whereas with Cu a pronounced and dose-dependent increase of Ca i 2+ was induced after a delay of 10 to 15 min, the calcium being of extracellular origin. Intracellular pH was not altered by Cd but decreased significantly in the presence of Cu. Overall our data demonstrate that Cu, but not Cd, is acutely toxic for trout hepatocytes. Since Cu does not enter the cells in the short term it appears to exert its acutely toxic effects at the cell membrane. Although Cu toxicity is associated with an uptake of calcium from extracellular space, leading to an elevation of cellular respiration, cytotoxicity does not appear to be dependent on the presence of extracellular calcium

  4. Comparison of stainless and mild steel welding fumes in generation of reactive oxygen species.

    Science.gov (United States)

    Leonard, Stephen S; Chen, Bean T; Stone, Samuel G; Schwegler-Berry, Diane; Kenyon, Allison J; Frazer, David; Antonini, James M

    2010-11-03

    Welding fumes consist of a wide range of complex metal oxide particles which can be deposited in all regions of the respiratory tract. The welding aerosol is not homogeneous and is generated mostly from the electrode/wire. Over 390,000 welders were reported in the U.S. in 2008 while over 1 million full-time welders were working worldwide. Many health effects are presently under investigation from exposure to welding fumes. Welding fume pulmonary effects have been associated with bronchitis, metal fume fever, cancer and functional changes in the lung. Our investigation focused on the generation of free radicals and reactive oxygen species from stainless and mild steel welding fumes generated by a gas metal arc robotic welder. An inhalation exposure chamber located at NIOSH was used to collect the welding fume particles. Our results show that hydroxyl radicals (.OH) were generated from reactions with H2O2 and after exposure to cells. Catalase reduced the generation of .OH from exposed cells indicating the involvement of H2O2. The welding fume suspension also showed the ability to cause lipid peroxidation, effect O2 consumption, induce H2O2 generation in cells, and cause DNA damage. Increase in oxidative damage observed in the cellular exposures correlated well with .OH generation in size and type of welding fumes, indicating the influence of metal type and transition state on radical production as well as associated damage. Our results demonstrate that both types of welding fumes are able to generate ROS and ROS-related damage over a range of particle sizes; however, the stainless steel fumes consistently showed a significantly higher reactivity and radical generation capacity. The chemical composition of the steel had a significant impact on the ROS generation capacity with the stainless steel containing Cr and Ni causing more damage than the mild steel. Our results suggest that welding fumes may cause acute lung injury. Since type of fume generated, particle size

  5. Comparison of stainless and mild steel welding fumes in generation of reactive oxygen species

    Directory of Open Access Journals (Sweden)

    Frazer David

    2010-11-01

    Full Text Available Abstract Background Welding fumes consist of a wide range of complex metal oxide particles which can be deposited in all regions of the respiratory tract. The welding aerosol is not homogeneous and is generated mostly from the electrode/wire. Over 390,000 welders were reported in the U.S. in 2008 while over 1 million full-time welders were working worldwide. Many health effects are presently under investigation from exposure to welding fumes. Welding fume pulmonary effects have been associated with bronchitis, metal fume fever, cancer and functional changes in the lung. Our investigation focused on the generation of free radicals and reactive oxygen species from stainless and mild steel welding fumes generated by a gas metal arc robotic welder. An inhalation exposure chamber located at NIOSH was used to collect the welding fume particles. Results Our results show that hydroxyl radicals (.OH were generated from reactions with H2O2 and after exposure to cells. Catalase reduced the generation of .OH from exposed cells indicating the involvement of H2O2. The welding fume suspension also showed the ability to cause lipid peroxidation, effect O2 consumption, induce H2O2 generation in cells, and cause DNA damage. Conclusion Increase in oxidative damage observed in the cellular exposures correlated well with .OH generation in size and type of welding fumes, indicating the influence of metal type and transition state on radical production as well as associated damage. Our results demonstrate that both types of welding fumes are able to generate ROS and ROS-related damage over a range of particle sizes; however, the stainless steel fumes consistently showed a significantly higher reactivity and radical generation capacity. The chemical composition of the steel had a significant impact on the ROS generation capacity with the stainless steel containing Cr and Ni causing more damage than the mild steel. Our results suggest that welding fumes may cause acute

  6. Toxicological assessment of combined lead and cadmium: acute and sub-chronic toxicity study in rats.

    Science.gov (United States)

    Yuan, Guiping; Dai, Shujun; Yin, Zhongqiong; Lu, Hongke; Jia, Renyong; Xu, Jiao; Song, Xu; Li, Li; Shu, Yang; Zhao, Xinghong

    2014-03-01

    The exposure to chemical mixtures is a common and important determinant of toxicity and receives concern for their introduction by inhalation and ingestion. However, few in vivo mixture studies have been conducted to understand the health effects of chemical mixtures compared with single chemicals. In this study, the acute and 90day sub-chronic toxicity tests of combined Pb and Cd were conducted. In the acute toxicity test, the LD50 value of Pb(NO3)2 and CdCl2 mixture by the oral route was 2696.54mg/kg by Bliss method. The sub-chronic treatment revealed that the low-dose combination of Pb and Cd exposures can significantly change the physiological and biochemical parameters of the blood of Sprague-Dawley (SD) rats with dose-response relationship and causes microcytic hypochromic anemia and the damages of liver and kidney of the SD rats to various degrees. Histopathological exams showed that the target organs of Pb and Cd were testicle, liver, and kidneys. These observations suggest that Pb and Cd are practically additive-toxic for the SD rats in oral acute toxicity studies. The lowest observed adverse-effect level in rats may be lower than a dose of 29.96mg/(kgbwday) when administered orally for 90 consecutive days. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Sensitivity of mottled sculpins (Cottus bairdi) and rainbow trout (Onchorhynchus mykiss) to acute and chronic toxicity of cadmium, copper, and zinc.

    Science.gov (United States)

    Besser, John M; Mebane, Christopher A; Mount, David R; Ivey, Chris D; Kunz, James L; Greer, I Eugene; May, Thomas W; Ingersoll, Christopher G

    2007-08-01

    Studies of fish communities of streams draining mining areas suggest that sculpins (Cottus spp.) may be more sensitive than salmonids to adverse effects of metals. We compared the toxicity of zinc, copper, and cadmium to mottled sculpin (C. bairdi) and rainbow trout (Onchorhynchus mykiss) in laboratory toxicity tests. Acute (96-h) and early life-stage chronic (21- or 28-d) toxicity tests were conducted with rainbow trout and with mottled sculpins from populations in Minnesota and Missouri, USA, in diluted well water (hardness = 100 mg/L as CaCO3). Acute and chronic toxicity of metals to newly hatched and swim-up stages of mottled sculpins differed between the two source populations. Differences between populations were greatest for copper, with chronic toxicity values (ChV = geometric mean of lowest-observed-effect concentration and no-observed-effect concentration) of 4.4 microg/L for Missouri sculpins and 37 microg/L for Minnesota sculpins. Cadmium toxicity followed a similar trend, but differences between sculpin populations were less marked, with ChVs of 1.1 microg/L (Missouri) and 1.9 microg/L (Minnesota). Conversely, zinc was more toxic to Minnesota sculpins (ChV = 75 microg/L) than Missouri sculpins (chronic ChV = 219 microg/L). Species-average acute and chronic toxicity values for mottled sculpins were similar to or lower than those for rainbow trout and indicated that mottled sculpins were among the most sensitive aquatic species to toxicity of all three metals. Our results indicate that current acute and chronic water quality criteria for cadmium, copper, and zinc adequately protect rainbow trout but may not adequately protect some populations of mottled sculpins. Proposed water quality criteria for copper based on the biotic ligand model would be protective of both sculpin populations tested.

  8. Comparative acute toxicity of gallium(III, antimony(III, indium(III, cadmium(II, and copper(II on freshwater swamp shrimp (Macrobrachium nipponense

    Directory of Open Access Journals (Sweden)

    Jen-Lee Yang

    2014-01-01

    Full Text Available BACKGROUND: Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. RESULTS: The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50 of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. CONCLUSIONS: Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.

  9. The Pozzolanic reaction of silica fume

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    2012-01-01

    Silica fume is a very important supplementary cementitious binder in High-Performance and Ultra High-Performance Concretes. Through its pozzolanic reaction the silica fume densifies the concrete micro-structure, in particular it strengthens the paste-aggregate interfacial transition zone....... In the present paper different aspects of the pozzolanic reaction of silica fume are investigated. These include chemical shrinkage, isothermal heat development and strength development. Key data for these are given and compared with theoretical calculations, and based on presented measurements the energy...... of activation of the pozzolanic reaction of silica fume is estimated. The results show that the pozzolanic reaction of silica fume has notable differences from Portland cement hydration....

  10. Acute effects of cadmium on osmoregulation of the freshwater teleost Prochilodus lineatus: Enzymes activity and plasma ions

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alexandre O.F. da [Departamento de Ciências Fisiológicas, Laboratório de Ecofisiologia Animal, UEL, Londrina (Brazil); Programa Multicêntrico de Pós-graduação em Ciências Fisiológicas, UEL, Londrina (Brazil); Centro de Ciências Humanas e da Educação, UENP, Jacarezinho (Brazil); Martinez, Cláudia B.R., E-mail: cbueno@uel.br [Departamento de Ciências Fisiológicas, Laboratório de Ecofisiologia Animal, UEL, Londrina (Brazil); Programa Multicêntrico de Pós-graduação em Ciências Fisiológicas, UEL, Londrina (Brazil)

    2014-11-15

    Highlights: • Cd effects were evaluated on plasma ions and ATPases of Prochilodus lineatus. • Fish were exposed to 1 and 10 μg Cd L{sup −1} for 24 and 96 h. • Na{sup +}/K{sup +}-ATPase and carbonic anhydrase decreased in gills and kidney after Cd exposure. • Gill Ca{sup 2+}-ATPase and plasma Ca{sup 2+} decreased after Cd exposure. • Cd concentrations set by Brazilian guidelines affect Ca{sup 2+} regulation of P. lineatus. - Abstract: Cadmium (Cd) is a trace element that is very toxic to fish. It is commonly found in surface waters contaminated with industrial effluents. When dissolved in water, Cd can rapidly cause physiological changes in the gills and kidneys of freshwater fish. The objective of this study was to evaluate the acute effects of Cd on the osmoregulation of the Neotropical fish Prochilodus lineatus. Juvenile fish were exposed to Cd at two concentrations [1 (Cd1) and 10 (Cd10) μg L{sup −1}] for 24 and 96 h. The effects of Cd were evaluated through the analysis of ions (Na{sup +}, K{sup +}, Ca{sup 2+}, and Cl{sup −}) and plasma osmolality, and by measuring the activities of enzymes involved in osmoregulation obtained from the gills and kidney. Fish exposed to Cd for 24 and 96 h showed a decrease in Na{sup +}/K{sup +}-ATPase activity in the gills and kidney. The activity of carbonic anhydrase decreased in the gills after 24 h and in both tissues after 96 h of Cd exposure. The gill Ca{sup 2+}-ATPase activity also decreased with Cd exposure, with a concomitant drop in the plasma concentration of Ca{sup 2+}. Despite the hypocalcemia, there were no changes in the concentration of the ions Na{sup +}, K{sup +}, and Cl{sup −} or in plasma osmolality. Among the enzymes involved in ion transport, H{sup +}-ATPase was the only enzyme that showed increased activity in gills, whereas its activity in kidney remained unchanged. The results of this study demonstrate that waterborne Cd at the maximum concentrations set by Brazilian guidelines for

  11. Acute effects of cadmium on osmoregulation of the freshwater teleost Prochilodus lineatus: Enzymes activity and plasma ions

    International Nuclear Information System (INIS)

    Silva, Alexandre O.F. da; Martinez, Cláudia B.R.

    2014-01-01

    Highlights: • Cd effects were evaluated on plasma ions and ATPases of Prochilodus lineatus. • Fish were exposed to 1 and 10 μg Cd L −1 for 24 and 96 h. • Na + /K + -ATPase and carbonic anhydrase decreased in gills and kidney after Cd exposure. • Gill Ca 2+ -ATPase and plasma Ca 2+ decreased after Cd exposure. • Cd concentrations set by Brazilian guidelines affect Ca 2+ regulation of P. lineatus. - Abstract: Cadmium (Cd) is a trace element that is very toxic to fish. It is commonly found in surface waters contaminated with industrial effluents. When dissolved in water, Cd can rapidly cause physiological changes in the gills and kidneys of freshwater fish. The objective of this study was to evaluate the acute effects of Cd on the osmoregulation of the Neotropical fish Prochilodus lineatus. Juvenile fish were exposed to Cd at two concentrations [1 (Cd1) and 10 (Cd10) μg L −1 ] for 24 and 96 h. The effects of Cd were evaluated through the analysis of ions (Na + , K + , Ca 2+ , and Cl − ) and plasma osmolality, and by measuring the activities of enzymes involved in osmoregulation obtained from the gills and kidney. Fish exposed to Cd for 24 and 96 h showed a decrease in Na + /K + -ATPase activity in the gills and kidney. The activity of carbonic anhydrase decreased in the gills after 24 h and in both tissues after 96 h of Cd exposure. The gill Ca 2+ -ATPase activity also decreased with Cd exposure, with a concomitant drop in the plasma concentration of Ca 2+ . Despite the hypocalcemia, there were no changes in the concentration of the ions Na + , K + , and Cl − or in plasma osmolality. Among the enzymes involved in ion transport, H + -ATPase was the only enzyme that showed increased activity in gills, whereas its activity in kidney remained unchanged. The results of this study demonstrate that waterborne Cd at the maximum concentrations set by Brazilian guidelines for freshwater affects the gills and kidney functions of P. lineatus. Acute exposure to

  12. Temporal changes in rat liver gene expression after acute cadmium and chromium exposure.

    Directory of Open Access Journals (Sweden)

    Michael S Madejczyk

    Full Text Available U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na(2Cr(2O(7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH, resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers.

  13. Temporal Changes in Rat Liver Gene Expression after Acute Cadmium and Chromium Exposure

    Science.gov (United States)

    Madejczyk, Michael S.; Baer, Christine E.; Dennis, William E.; Minarchick, Valerie C.; Leonard, Stephen S.; Jackson, David A.; Stallings, Jonathan D.; Lewis, John A.

    2015-01-01

    U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na2Cr2O7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH), resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers. PMID:25993096

  14. Acute toxicity of cadmium, lead, zinc, and their mixtures to stream-resident fish and invertebrates

    Science.gov (United States)

    Mebane, Christopher A.; Dillon, Frank S.; Hennessy, Daniel P.

    2012-01-01

    The authors conducted 150 tests of the acute toxicity of resident fish and invertebrates to Cd, Pb, and Zn, separately and in mixtures, in waters from the South Fork Coeur d'Alene River watershed, Idaho, USA. Field-collected shorthead sculpin (Cottus confusus), westslope cutthroat trout (Oncorhynchus clarkii lewisi), two mayflies (Baetis tricaudatus and Rhithrogena sp.), a stonefly (Sweltsa sp.), a caddisfly (Arctopsyche sp.), a snail (Gyraulus sp.), and hatchery rainbow trout (Oncorhynchus mykiss), were tested with all three metals. With Pb, the mayflies (Drunella sp., Epeorus sp., and Leptophlebiidae), a Simuliidae black fly, a Chironomidae midge, a Tipula sp. crane fly, a Dytiscidae beetle, and another snail (Physa sp.), were also tested. Adult westslope cutthroat trout were captured to establish a broodstock to provide fry of known ages for testing. With Cd, the range of 96-h median effect concentrations (EC50s) was 0.4 to >5,329μg/L, and the relative resistances of taxa were westslope cutthroat trout ≈ rainbow trout ≈ sculpin << other taxa; with Pb, EC50s ranged from 47 to 3,323μg/L, with westslope cutthroat trout < rainbow trout < other taxa; and with Zn, EC50s ranged from 21 to 3,704μg/L, with rainbow trout < westslope cutthroat trout ≈ sculpin << other taxa. With swim-up trout fry, a pattern of decreasing resistance with increasing fish size was observed. In metal mixtures, the toxicities of the three metals were less than additive on a concentration-addition basis.

  15. Biochemical biomarker responses of green-lipped mussel, Perna canaliculus, to acute and subchronic waterborne cadmium toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Chandurvelan, Rathishri, E-mail: rch118@uclive.ac.nz [School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand); Marsden, Islay D., E-mail: islay.marsden@canterbury.ac.nz [School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand); Gaw, Sally, E-mail: sally.gaw@canterbury.ac.nz [Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand); Glover, Chris N., E-mail: chris.glover@canterbury.ac.nz [School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand)

    2013-09-15

    Highlights: •Biochemical biomarkers were measured to assess effects of Cd on Perna canaliculus. •Biochemical responses varied between acute and subchronic exposure to Cd. •MTLP induction correlated strongly with Cd accumulation. •Alkaline phosphatase and glycogen levels decreased during subchronic Cd exposure. •Duration of Cd exposure influenced biochemical biomarker responses in mussels. -- Abstract: The biochemical responses of the green-lipped mussel, Perna canaliculus, to waterborne cadmium (Cd) were investigated in order to delineate toxic mechanisms, and the impacts of exposure dose and duration, of this important toxicant in a potential sentinel species. Mussels were exposed for either 96 h (acute: 0, 2000, 4000 μg L{sup −1} Cd) or for 28 d (subchronic: 0, 200, 2000 μg L{sup −1} Cd), and the digestive gland, gill and haemolymph were examined for impacts. Biochemical responses measured included those associated with metal detoxification (metallothionein-like protein; MTLP), oxidative stress (catalase, lipid peroxidation), cellular homeostasis (alkaline phosphatase, Na{sup +}, K{sup +}-ATPase; NKA), and energy utilisation (glycogen, haemolymph protein). Following acute exposure, digestive gland glycogen and gill NKA activity were significantly altered by Cd exposure relative to levels in mussels exposed to Cd-free seawater. Subchronic Cd exposure resulted in a significant increase in MTLP levels in both the gill and the digestive gland. This increase was correlated strongly with the levels of Cd accumulation measured in these tissues (R = 0.957 for gill, 0.964 for digestive gland). Catalase activity followed a similar pattern, although the correlation with tissue Cd accumulation was not as strong (R = 0.907 for gill, 0.708 for digestive gland) as that for MTLP. Lipid peroxidation increased in the digestive gland at Days 7 and 14 at both subchronic Cd levels tested, but this effect had largely dissipated by Days 21 and 28 (with the exception of

  16. Perturbations in ROS-related processes of the fish Gambusia holbrooki after acute and chronic exposures to the metals copper and cadmium.

    Science.gov (United States)

    Nunes, Bruno; Caldeira, Carina; Pereira, Joana Luísa; Gonçalves, Fernando; Correia, Alberto Teodorico

    2015-03-01

    Metallic contamination is a widespread phenomena, particularly in areas impacted by human activities, and has become a relevant environmental concern. However, the toxicity of metals on fish requires full characterization in terms of short- and long-term effects. Thus, the purpose of this study was to determine the acute and chronic oxidative stress response in liver and gills of Gambusia holbrooki exposed to copper and cadmium. To assess the effects of these two metals, we adopted a strategy of analyzing the pollution effects caused by salts of the two metallic elements, and we quantified the oxidative stress biomarkers catalase, glutathione reductase, glutathione-S-transferases, and lipid peroxidation after exposure (4 and 28 days) to ecologically relevant concentrations, thus simulating actual conditions of exposure in the wild. Our results showed that copper elicited strong effects in all tested biomarkers for both acute and chronic challenges. Cadmium caused a similar response and was shown to cause significant changes particularly in catalase and glutathione-S-transferases activities. These findings evidence that ecologically relevant concentrations of common anthropogenic contaminants are causative agents of serious imbalances (namely oxidative stress) that are likely to trigger life-threatening events.

  17. Circadian time-dependent antioxidant and inflammatory responses to acute cadmium exposure in the brain of zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jia-Lang, E-mail: zhengjialang@aliyun.com; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming; Zhu, Ai-Yi

    2017-01-15

    Highlights: • Gene changed at mRNA, protein and activity levels between exposure time points. • ROS mediated antioxidant and inflammatory responses by Nrf2 and NF-κB. • The effect of time of day on Cd-induced toxicity should not be neglected in fish. - Abstract: Up to date, little information is available on effects of circadian rhythm on metal-induced toxicity in fish. In this study, zebrafish were acutely exposed to 0.97 mg L{sup −1} cadmium for 12 h either at ZT0 (the light intensity began to reached maximum) or at ZT12 (light intensity began to reached minimum) to evaluate the temporal sensitivity of oxidative stress and inflammatory responses in the brain of zebrafish. Profiles of responses of some genes at mRNA, protein and activity levels were different between ZT0 and ZT12 in the normal water. Exposure to Cd induced contrary antioxidant responses and similar inflammatory responses between ZT0 and ZT12. However, the number of inflammatory genes which were up-regulated was significantly greater at ZT12 than at ZT0. And, the up-regulated inflammatory genes were more responsive at ZT12 than at ZT0. At ZT12, antioxidant genes were down-regulated at mRNA, protein and activity levels. Contrarily, antioxidant genes were not affected at mRNA levels but activated at the protein and/or activity levels at ZT0. Reactive oxygen species (ROS) sharply increased and remained relatively stable when fish were exposed to Cd at ZT12 and ZT0, respectively. Positive correlations between ROS levels and mRNA levels of nuclear transcription factor κB (NF-κB) and between mRNA levels of NF-κB and its target genes were observed, suggesting that ROS may play an essential role in regulating the magnitude of inflammatory responses. Taken together, oxidative stress and immunotoxicity in the brain were more serious when fish were exposed to Cd in the evening than in the morning, highlighting the importance of circadian rhythm in Cd-induced neurotoxicity in fish.

  18. Acute and chronic toxicity of cadmium to different life history stages of the freshwater crustacean Asellus aquaticus (L)

    Energy Technology Data Exchange (ETDEWEB)

    Green, D.W.J.; Williams, K.A.; Pascoe, D.

    1986-09-01

    Different life-history stages of the freshwater isopod crustacean Asellus aquaticus were exposed to a range of cadmium concentrations using a semi-static toxicity testing procedure. Median lethal concentrations (96-hr LC50) ranged from 80 ..mu..g Cd/L for juveniles to > 2000 ..mu..g Cd/L for embryos. Pre-treatment of eggs with cadmium did not increase their tolerance to the metal as juveniles. The responses of each stage are discussed in relation to the use of macroinvertebrate toxicity test data in predicting the hazardous effects of pollutants.

  19. Oral cadmium chloride intoxication in mice

    DEFF Research Database (Denmark)

    Andersen, O; Nielsen, J B; Svendsen, P

    1988-01-01

    Diethyldithiocarbamate (DDC) is known to alleviate acute toxicity due to injection of cadmium salts. However, when cadmium chloride was administered by the oral route, DDC enhanced rather than alleviated the acute toxicity; both oral and intraperitoneal (i.p.) administration of DDC had this effect...

  20. Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    Science.gov (United States)

    Ingersoll, Christopher G.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

    2014-01-01

    White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from

  1. Response of the mouse lung transcriptome to welding fume: effects of stainless and mild steel fumes on lung gene expression in A/J and C57BL/6J mice

    Directory of Open Access Journals (Sweden)

    Antonini James M

    2010-06-01

    Full Text Available Abstract Background Debate exists as to whether welding fume is carcinogenic, but epidemiological evidence suggests that welders are an at risk population for the development of lung cancer. Recently, we found that exposure to welding fume caused an acutely greater and prolonged lung inflammatory response in lung tumor susceptible A/J versus resistant C57BL/6J (B6 mice and a trend for increased tumor incidence after stainless steel (SS fume exposure. Here, our objective was to examine potential strain-dependent differences in the regulation and resolution of the lung inflammatory response induced by carcinogenic (Cr and Ni abundant or non-carcinogenic (iron abundant metal-containing welding fumes at the transcriptome level. Methods Mice were exposed four times by pharyngeal aspiration to 5 mg/kg iron abundant gas metal arc-mild steel (GMA-MS, Cr and Ni abundant GMA-SS fume or vehicle and were euthanized 4 and 16 weeks after the last exposure. Whole lung microarray using Illumina Mouse Ref-8 expression beadchips was done. Results Overall, we found that tumor susceptibility was associated with a more marked transcriptional response to both GMA-MS and -SS welding fumes. Also, Ingenuity Pathway Analysis revealed that gene regulation and expression in the top molecular networks differed between the strains at both time points post-exposure. Interestingly, a common finding between the strains was that GMA-MS fume exposure altered behavioral gene networks. In contrast, GMA-SS fume exposure chronically upregulated chemotactic and immunomodulatory genes such as CCL3, CCL4, CXCL2, and MMP12 in the A/J strain. In the GMA-SS-exposed B6 mouse, genes that initially downregulated cellular movement, hematological system development/function and immune response were involved at both time points post-exposure. However, at 16 weeks, a transcriptional switch to an upregulation for neutrophil chemotactic genes was found and included genes such as S100A8, S100A9 and

  2. High effective silica fume alkali activator

    Indian Academy of Sciences (India)

    Unknown

    Development of compressive strength of mortars depending on the alkali activator used and the composition of the binder and the time of hardening. 1. Slag + NaOH; 2. Silica fume activator + slag; 3. Portland cement + water; 4. 70% Port- land cement + 30% slag + water glass; 5. 30% Portland cement. + 70% slag + water; 6.

  3. Persistence of Change: Fume Hood Campaign Lessons

    Science.gov (United States)

    Feder, Elah; Robinson, Jennifer; Wakefield, Sarah

    2012-01-01

    Purpose: Sustainability initiatives typically operate for a limited time period, but it is often unclear whether they have lasting effects. The purpose of this paper is to examine a laboratory fume hood campaign, in order to identify factors that might contribute or detract from long-term change persistence. Design/methodology/approach: The…

  4. Effect of cadmium chloride on hepatic lipid peroxidation in mice

    DEFF Research Database (Denmark)

    Andersen, H R; Andersen, O

    1988-01-01

    Intraperitoneal administration of cadmium chloride to 8-12 weeks old CBA-mice enhanced hepatic lipid peroxidation. A positive correlation between cadmium chloride dose and level of peroxidation was observed in both male and female mice. A sex-related difference in mortality was not observed....... The mortality after an acute toxic dose of cadmium chloride was the same in the three age groups. Pretreatment of mice with several low intraperitoneal doses of cadmium chloride alleviated cadmium induced mortality and lipid peroxidation. The results demonstrate both age dependency and a protective effect...... of metallothionein induction on cadmium chloride induced hepatic lipid peroxidation....

  5. Effects of diethyldithiocarbamate on the toxicokinetics of cadmium chloride in mice

    DEFF Research Database (Denmark)

    Andersen, O; Nielsen, J B

    1989-01-01

    investigates effects of DDC on the toxicokinetics of cadmium at lower doses of cadmium than those used in previous studies. During single exposure to subtoxic oral doses of cadmium chloride DDC enhanced intestinal cadmium absorption, both after intraperitoneal and oral administration of DDC. In such acute...... exposure experiments orally administered DDC only slightly changed the relative organ distribution of absorbed cadmium, while intraperitoneal administration of DDC induced extensive changes in organ preference of absorbed cadmium. The relative hepatic and testicular deposition was reduced, while......Diethyldithiocarbamate (DDC) efficiently alleviates the acute toxicity of injected cadmium chloride, but enhances the acute toxicity of orally administered cadmium chloride. Further, DDC induces extensive changes in organ distribution of cadmium, and mobilizes aged cadmium depots. The present study...

  6. Repetitive Dosing of Fumed Silica Leads to Profibrogenic Effects through Unique Structure-Activity Relationships and Biopersistence in the Lung.

    Science.gov (United States)

    Sun, Bingbing; Wang, Xiang; Liao, Yu-Pei; Ji, Zhaoxia; Chang, Chong Hyun; Pokhrel, Suman; Ku, Justine; Liu, Xiangsheng; Wang, Meiying; Dunphy, Darren R; Li, Ruibin; Meng, Huan; Mädler, Lutz; Brinker, C Jeffrey; Nel, André E; Xia, Tian

    2016-08-23

    Contrary to the notion that the use of fumed silica in consumer products can "generally (be) regarded as safe" (GRAS), the high surface reactivity of pyrogenic silica differs from other forms of synthetic amorphous silica (SAS), including the capacity to induce membrane damage and acute proinflammatory changes in the murine lung. In addition, the chain-like structure and reactive surface silanols also allow fumed silica to activate the NLRP3 inflammasome, leading to IL-1β production. This pathway is known to be associated with subchronic inflammation and profibrogenic effects in the lung by α-quartz and carbon nanotubes. However, different from the latter materials, bolus dose instillation of 21 mg/kg fumed silica did not induce sustained IL-1β production or subchronic pulmonary effects. In contrast, the NLRP3 inflammasome pathway was continuously activated by repetitive-dose administration of 3 × 7 mg/kg fumed silica, 1 week apart. We also found that while single-dose exposure failed to induce profibrotic effects in the lung, repetitive dosing can trigger increased collagen production, even at 3 × 3 mg/kg. The change between bolus and repetitive dosing was due to a change in lung clearance, with recurrent dosing leading to fumed silica biopersistence, sustained macrophage recruitment, and activation of the NLRP3 pathway. These subchronic proinflammatory effects disappeared when less surface-reactive titanium-doped fumed silica was used for recurrent administration. All considered, these data indicate that while fumed silica may be regarded as safe for some applications, we should reconsider the GRAS label during repetitive or chronic inhalation exposure conditions.

  7. Repetitive Dosing of Fumed Silica Leads to Profibrogenic Effects through Unique Structure–Activity Relationships and Biopersistence in the Lung

    International Nuclear Information System (INIS)

    Sun, Bingbing; Wang, Xiang; Liao, Yu-Pei; Ji, Zhaoxia; Chang, Chong Hyun

    2016-01-01

    Contrary to the notion that the use of fumed silica in consumer products can “generally (be) regarded as safe” (GRAS), the high surface reactivity of pyrogenic silica differs from other forms of synthetic amorphous silica (SAS), including the capacity to induce membrane damage and acute proinflammatory changes in the murine lung. Additionally, the chain-like structure and reactive surface silanols also allow fumed silica to activate the NLRP3 inflammasome, leading to IL-1β production. This pathway is known to be associated with subchronic inflammation and profibrogenic effects in the lung by α-quartz and carbon nanotubes. Different from the latter materials, bolus dose instillation of 21 mg/kg fumed silica did not induce sustained IL-1β production or subchronic pulmonary effects. In contrast, the NLRP3 inflammasome pathway was continuously activated by repetitive-dose administration of 3 × 7 mg/kg fumed silica, 1 week apart. We also found that while single-dose exposure failed to induce profibrotic effects in the lung, repetitive dosing can trigger increased collagen production, even at 3 × 3 mg/kg. The change between bolus and repetitive dosing was due to a change in lung clearance, with recurrent dosing leading to fumed silica biopersistence, sustained macrophage recruitment, and activation of the NLRP3 pathway. These subchronic proinflammatory effects disappeared when less surface-reactive titanium-doped fumed silica was used for recurrent administration. Finally, these data indicate that while fumed silica may be regarded as safe for some applications, we should reconsider the GRAS label during repetitive or chronic inhalation exposure conditions.

  8. Parental Occupational Exposure to Heavy Metals and Welding Fumes and Risk of Testicular Germ Cell Tumors in Offspring

    DEFF Research Database (Denmark)

    Togawa, Kayo; Le Cornet, Charlotte; Feychting, Maria

    2016-01-01

    registries. Information on parental occupations was retrieved from censuses. From this, we estimated prenatal/preconception exposures of chromium, iron, nickel, lead, and welding fumes (all three countries), and cadmium (Finland only) for each parent using job-exposure matrices specifying prevalence (P......BACKGROUND: Data are scarce on the association between prenatal/preconception environmental exposure and testicular germ cell tumor (TGCT) in offspring. We examined parental occupational exposures to heavy metals and welding fumes in relation to TGCT in offspring in a registry-based case......) and mean exposure level (L). Exposure indices were calculated as a product of P and L (P × L), and exposure categories were based on P × L or different combinations of P and L. RESULTS: The study comprised 8,112 cases and 26,264 controls. We observed no statistically significant TGCT risk associated...

  9. Cognitive symptoms and welding fume exposure.

    Science.gov (United States)

    Ross, John A S; Macdiarmid, Jennifer I; Semple, Sean; Watt, Stephen J; Moir, Gill; Henderson, George

    2013-01-01

    Prevalence of moderate to severe cognitive symptoms is markedly higher in UK professional divers who have also worked as a welder (28%) than in either divers who have not welded (18%) or offshore workers who have worked neither as a diver nor as a welder (6%). To determine whether cognitive symptoms are related to welding fume exposure or diving. Three age-matched groups of male workers were studied using postal questionnaire: professional divers who had worked as a welder (PDW, n = 361), professional welders who had not dived (NDW, n = 352), and offshore oil field workers who had neither dived nor welded (NDNW, n =503). Health-related quality of life was assessed by the Short Form 12 questionnaire (SF12). Cognitive symptomatology was assessed using the Cognitive Failures Questionnaire (CFQ). A single variable for welding fume exposure (mg m(-3) days) was calculated, incorporating welding experience in different environments and using different welding techniques and respiratory protective equipment. The level of fume exposure during hyperbaric welding operations was measured during such work as ambient PM(10) (particles of 10 µm or less). Diving exposure was assessed as the number of dives performed plus the number of days spent working during saturation diving. Questionnaires were returned by 153 PDW, 108 NDW, and 252 NDNW. SF12 scores were the same in all groups and fell within normative values. Mean (95% CI) CFQ scores were higher in PDW [40.3 (37.7-42.9)] than in both NDW [34.6 (31.6-37.7)] and NDNW [32.1 (30.4-33.9)], but the scores in no groups fell outside the normative range. The mean PM(10) exposure during hyperbaric welding operations was 2.58 mg m(-3). The geometric mean mg m(-3) days (95% CI) for welding fume exposure in NDW [33 128 (24 625-44 567) n = 85] was higher than for that in PDW [10 904 (8103-14 673) n = 112]. For PDW the geometric mean (95% CI) diving exposure was 1491 [(1192-1866) n = 94] dives and days in saturation. In the general linear

  10. Characterisation of fume from hyperbaric welding operations

    Energy Technology Data Exchange (ETDEWEB)

    Ross, John A S; Semple, Sean [Environmental and Occupational Medicine, University of Aberdeen (United Kingdom); Duffin, Rodger [ELEGI Colt Laboratory, University of Edinburgh (United Kingdom); Kelly, Frank [Lung Biology Group, Kings College, University of London (United Kingdom); Seldmann, Joerg; Raab, Andrea, E-mail: j.a.ross@abdn.ac.u [Trace Element Speciation Laboratory, University of Aberdeen (United Kingdom)

    2009-02-01

    We report preliminary work characterising dust from hyperbaric welding trials carried out at increased pressure in a helium and oxygen atmosphere. Particle size and concentration were measured during welding. Samples for quartz and metal analysis and toxicity assessment were taken from a filter in the local fume extraction system. The residue of dust after metal extraction by nitric acid in hydrogen peroxide predominantly a non-metallic white powder assumed to be dust from welding rod coatings and thermal insulation material. Metallic analysis showed predominantly calcium, from the welding rod coating, and period 4 transition metals such as iron, manganese, magnesium and titanium (inductively coupled mass spectrometry, Agilent 7500c). The presence of zirconium indicated a contribution from grinding. The fume was nanoparticulate in nature with a mean particle diameter of 20-30 nm (MSI Inc WPS 1000XP). It showed an intermediate level of oxidative potential regarding the low-molecular weight respiratory tract lining fluid antioxidants ascorbate and glutathione and caused release of the inflammatory marker IL-8 in a human lung A 549 epithelial cell culture with no indication of cytotoxicity. The study findings have strong implications for the measurement techniques needed to assess fume exposure in hyperbaric welding and the provision of respiratory protection.

  11. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures.

    Science.gov (United States)

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-10-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model-normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution. © 2014 The Authors. This article is a US Government work and is in the public domain in the United States of America.

  12. Prediction of acute toxicity of cadmium and lead to zebrafish larvae by using a refined toxicokinetic-toxicodynamic model

    International Nuclear Information System (INIS)

    Gao, Yongfei; Feng, Jianfeng; Zhu, Lin

    2015-01-01

    Highlights: • We developed a BLM-aided TK-TD model that considers the effects of H + . • The time-course metal concentration in larvae was well described by the TK model. • The time-course survival of zebrafish larvae was well simulated by the TD model. - Abstract: The biotic ligand model (BLM) and the toxicokinetic-toxicodynamic (TK-TD) model are essential in predicting the acute toxicity of metals in various species and exposure conditions; however, these models are usually separately utilized. In this study, a mechanistic TK-TD model was developed to predict the acute toxicity of 10 −6 M Cd and 10 −6 M Pb to zebrafish (Danio rerio) larvae. The novel approach links the BLM with relevant TK processes to simulate the bioaccumulation processes of Cd or Pb as a function of the maximum uptake rate of each metal, the affinity constants, and the concentrations of free metal ions and H + in test solutions. Results showed that the refined TK-TD model can accurately predict the accumulation and acute toxicity of Cd and Pb to zebrafish larvae at pH 5.5, 6.5, and 7.0.

  13. Prediction of acute toxicity of cadmium and lead to zebrafish larvae by using a refined toxicokinetic-toxicodynamic model

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yongfei; Feng, Jianfeng, E-mail: fengjf@nankai.edu.cn; Zhu, Lin, E-mail: zhulin@nankai.edu.cn

    2015-12-15

    Highlights: • We developed a BLM-aided TK-TD model that considers the effects of H{sup +}. • The time-course metal concentration in larvae was well described by the TK model. • The time-course survival of zebrafish larvae was well simulated by the TD model. - Abstract: The biotic ligand model (BLM) and the toxicokinetic-toxicodynamic (TK-TD) model are essential in predicting the acute toxicity of metals in various species and exposure conditions; however, these models are usually separately utilized. In this study, a mechanistic TK-TD model was developed to predict the acute toxicity of 10{sup −6} M Cd and 10{sup −6} M Pb to zebrafish (Danio rerio) larvae. The novel approach links the BLM with relevant TK processes to simulate the bioaccumulation processes of Cd or Pb as a function of the maximum uptake rate of each metal, the affinity constants, and the concentrations of free metal ions and H{sup +} in test solutions. Results showed that the refined TK-TD model can accurately predict the accumulation and acute toxicity of Cd and Pb to zebrafish larvae at pH 5.5, 6.5, and 7.0.

  14. Dry fumes purifying system using anhydrous baking soda; Procede chimique d`epuration des fumees au bicarbonate de soude anhydre

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-04-01

    UNISYSTEMS has developed the industrial implementation of the chemical process using anhydrous backing soda, patented by SOLVAY, for purifying fumes containing inorganic salts and sulphur oxides as polluting agents. The system can be applied to industrial processes releasing this type of polluting agents in the fumes at a temperature over 160 deg C, as it is specially indicated in purifying fumes coming from ceramic firing kilns. (authors)

  15. Acute exposure to waterborne cadmium induced oxidative stress and immunotoxicity in the brain, ovary and liver of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jia-Lang, E-mail: zhengjialang@aliyun.com; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming

    2016-11-15

    Highlights: • Cd induced oxidative stress and immunotoxicity by the generation of ROS. • The toxic effects depended on exposure time and different tissues. • Nrf2 and NF-κB mediated antioxidant and inflammatory responses. • Gene changed at transcriptional, translational, post-translational levels. - Abstract: Cadmium (Cd) is an environmental contaminant that poses serious risks to aquatic organisms and their associated ecosystem. The mechanisms underlying Cd-induced oxidative stress and immunotoxicity in fish remain largely unknown. In this study, adult female zebrafish were exposed to 0 (control), 1 mg L{sup −1} Cd for 24 h and 96 h, and the oxidative stress and inflammatory responses induced by Cd were evaluated in the brain, liver and ovary. Reactive oxygen species (ROS), nitric oxide (NO), and malondialdehyde (MDA) increased in a time-dependent manner after treatment with Cd in the brain and liver. The increase may result from the disturbance of genes including copper and zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), inducible nitric oxide synthase (iNOS), and ciclooxigenase-2 (COX-2) at mRNA, protein and activity levels. Although ROS, NO and MDA were not significantly affected by Cd in the ovary, the up-regulation of Cu/Zn-SOD, CAT, iNOS, and COX-2 was observed. Exposure to Cd induced a sharp increase in the protein levels of tumor necrosis factor alpha (TNF-α) in the brain, liver and ovary, possibly contributing to activate inflammatory responses. Furthermore, we also found a dramatic increase in mRNA levels of NF-E2-related factor 2 (Nrf2) and nuclear transcription factor κB (NF-κB) at 24 h in the liver and ovary. The corresponding changes in the mRNA levels of Kelch-like-ECH-associated protein 1 (Keap1a and Keap1b) and the inhibitor of κBα (IκBαa and IκBαb) may contribute to regulate the transcriptional activity of Nrf2 and NF-κB, respectively. Contrarily, mRNA levels of Nrf2, NF-κB, Keap1, Keap1b, IκBαa and IκBαb remained

  16. Acute exposure to waterborne cadmium induced oxidative stress and immunotoxicity in the brain, ovary and liver of zebrafish (Danio rerio).

    Science.gov (United States)

    Zheng, Jia-Lang; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming

    2016-11-01

    Cadmium (Cd) is an environmental contaminant that poses serious risks to aquatic organisms and their associated ecosystem. The mechanisms underlying Cd-induced oxidative stress and immunotoxicity in fish remain largely unknown. In this study, adult female zebrafish were exposed to 0 (control), 1mgL -1 Cd for 24h and 96h, and the oxidative stress and inflammatory responses induced by Cd were evaluated in the brain, liver and ovary. Reactive oxygen species (ROS), nitric oxide (NO), and malondialdehyde (MDA) increased in a time-dependent manner after treatment with Cd in the brain and liver. The increase may result from the disturbance of genes including copper and zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), inducible nitric oxide synthase (iNOS), and ciclooxigenase-2 (COX-2) at mRNA, protein and activity levels. Although ROS, NO and MDA were not significantly affected by Cd in the ovary, the up-regulation of Cu/Zn-SOD, CAT, iNOS, and COX-2 was observed. Exposure to Cd induced a sharp increase in the protein levels of tumor necrosis factor alpha (TNF-α) in the brain, liver and ovary, possibly contributing to activate inflammatory responses. Furthermore, we also found a dramatic increase in mRNA levels of NF-E2-related factor 2 (Nrf2) and nuclear transcription factor κB (NF-κB) at 24h in the liver and ovary. The corresponding changes in the mRNA levels of Kelch-like-ECH-associated protein 1 (Keap1a and Keap1b) and the inhibitor of κBα (IκBαa and IκBαb) may contribute to regulate the transcriptional activity of Nrf2 and NF-κB, respectively. Contrarily, mRNA levels of Nrf2, NF-κB, Keap1, Keap1b, IκBαa and IκBαb remained stable at 24 and 96h in the brain. Taken together, we demonstrated Cd-induced oxidative stress and immunotoxicity in fish, possibly through transcriptional regulation of Nrf2 and NF-κB and gene modifications at transcriptional, translational, post-translational levels, which would greatly extend our understanding on the Cd

  17. Acute exposure to waterborne cadmium induced oxidative stress and immunotoxicity in the brain, ovary and liver of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Zheng, Jia-Lang; Yuan, Shuang-Shuang; Wu, Chang-Wen; Lv, Zhen-Ming

    2016-01-01

    Highlights: • Cd induced oxidative stress and immunotoxicity by the generation of ROS. • The toxic effects depended on exposure time and different tissues. • Nrf2 and NF-κB mediated antioxidant and inflammatory responses. • Gene changed at transcriptional, translational, post-translational levels. - Abstract: Cadmium (Cd) is an environmental contaminant that poses serious risks to aquatic organisms and their associated ecosystem. The mechanisms underlying Cd-induced oxidative stress and immunotoxicity in fish remain largely unknown. In this study, adult female zebrafish were exposed to 0 (control), 1 mg L −1 Cd for 24 h and 96 h, and the oxidative stress and inflammatory responses induced by Cd were evaluated in the brain, liver and ovary. Reactive oxygen species (ROS), nitric oxide (NO), and malondialdehyde (MDA) increased in a time-dependent manner after treatment with Cd in the brain and liver. The increase may result from the disturbance of genes including copper and zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), inducible nitric oxide synthase (iNOS), and ciclooxigenase-2 (COX-2) at mRNA, protein and activity levels. Although ROS, NO and MDA were not significantly affected by Cd in the ovary, the up-regulation of Cu/Zn-SOD, CAT, iNOS, and COX-2 was observed. Exposure to Cd induced a sharp increase in the protein levels of tumor necrosis factor alpha (TNF-α) in the brain, liver and ovary, possibly contributing to activate inflammatory responses. Furthermore, we also found a dramatic increase in mRNA levels of NF-E2-related factor 2 (Nrf2) and nuclear transcription factor κB (NF-κB) at 24 h in the liver and ovary. The corresponding changes in the mRNA levels of Kelch-like-ECH-associated protein 1 (Keap1a and Keap1b) and the inhibitor of κBα (IκBαa and IκBαb) may contribute to regulate the transcriptional activity of Nrf2 and NF-κB, respectively. Contrarily, mRNA levels of Nrf2, NF-κB, Keap1, Keap1b, IκBαa and IκBαb remained

  18. Identification of sulfur fumed Pinelliae Rhizoma using an electronic nose.

    Science.gov (United States)

    Zhou, Xia; Wan, Jun; Chu, Liang; Liu, Wengang; Jing, Yafeng; Wu, Chunjie

    2014-01-01

    Pinelliae Rhizoma is a commonly used Chinese herb which will change brown during the natural drying process. However, sulfur fumed Pinelliae Rhizoma will get a better appearance than naturally dried one. Sulfur fumed Pinelliae Rhizoma is potentially toxical due to sulfur dioxide and sulfites formed during the fuming procedures. The odor components in sulfur fumed Pinelliae Rhizoma is complex. At present, there is no analytical method available to determine sulfur fumed Pinelliae Rhizoma simply and rapidly. To ensure medication safety, it is highly desirable to have an effective and simple method to identify sulfur fumed Pinelliae Rhizoma. This paper presents a novel approach using an electronic nose based on metal oxide sensors to identify whether Pinelliae Rhizoma was fumed with sulfur, and to predict the fuming degree of Pinelliae Rhizoma. Multivariate statistical methods such as principal components analysis (PCA), discriminant factorial analysis (DFA) and partial least squares (PLS) were used for data analyzing and identification. The use of the electronic nose to discriminate between different fuming degrees Pinelliae Rhizoma and naturally dried Pinelliae Rhizoma was demonstrated. The electronic nose was also successfully applied to identify unknown samples including sulfur fumed samples and naturally dried samples, high recognition value was obtained. Quantitative analysis of fuming degree of Pinelliae Rhizoma was also demonstrated. The method developed is simple and fast, which provides a new quality control method of Chinese herbs from the aspect of odor. It has shown that this electronic nose based metal oxide sensor is sensitive to sulfur and sulfides. We suggest that it can serve as a supportive method to detect residual sulfur and sulfides.

  19. Toxic effects of Cadmium on the garden snail (Helix aspersa)

    Energy Technology Data Exchange (ETDEWEB)

    Russell, L.K. (Northrop Services Inc., Corvallis, OR); DeHaven, J.I.; Botts, R.P.

    1981-05-01

    Spreading treated municipal wastes on agricultural and forest lands is becoming an established method of disposal. However, there is concern about the deleterious effects of toxicants, particularly cadmium, in the sludges. Cadmium concentrations in sewage sludge have been reported as high as 1500 ppM. The work reported here is a part of a larger project to investigate the ecological effects of municipal wastes on forest lands. Snails, Helix aspersa, were chosen to examine the entrance of cadmium into terrestrial food chains. This experiment was designed to determine cadmium accumulation, acute toxicity, and behavioral, reproductive and growth responses with increasing levels of cadmium.

  20. Effect of age on acute toxicity of cadmium, copper, nickel, and zinc in individual-metal exposures to Daphnia magna neonates.

    Science.gov (United States)

    Traudt, Elizabeth M; Ranville, James F; Meyer, Joseph S

    2017-01-01

    In previous studies, variability was high among replicate acute cadmium (Cd) Daphnia magna lethality tests (e.g., >10-fold range of median effect concentrations [EC50s]), less among zinc (Zn) tests, and relatively low for copper (Cu) and nickel (Ni) tests. Although the US Environmental Protection Agency's (USEPA's) protocol includes starting toxicity tests with neonates less than 24 h old, the authors hypothesized that age-related differences in sensitivity to metals might occur even within that relatively narrow age range. Daphnia magna neonates were collected during 3 age windows (0-4 h, 10-14 h, and 20-24 h old) and immediately exposed to each of the 4 metals for 48 h using the standard USEPA protocol. In repeated sets of tests during different weeks, the Cd EC50 of the youngest neonates was approximately 10-fold greater than the EC50 of the oldest neonates (i.e., Cd was less toxic to the youngest neonates) and the EC50 of neonates aged 10 h to 14 h was intermediate. Age-related differences were negligible in Cu, Ni, and Zn tests. Therefore, variability in toxicity of Cd may partly be caused by temporal variability in neonate age at the start of toxicity tests. Decreasing the age range of D. magna used in toxicity tests could help to improve the accuracy and precision of toxicity models, particularly for metal mixtures. Environ Toxicol Chem 2017;36:113-119. © 2016 SETAC. © 2016 SETAC.

  1. Analysis of silica fume produced by zircon desilication.

    Science.gov (United States)

    Phillips, D N; Carter, J

    2003-07-27

    Novel chemical methods have been developed to allow for the determination of the components of silica fume produced by zircon desilication. Hitherto, no methods have been described for the analysis of this material. The amorphous silica is first removed by treatment with sodium hydroxide. The residue from the hydroxide treatment may then be subjected to a suite of reagents to determine the zircon, the total zirconia, the monoclinic zirconia and the tetragonal zirconia content of the fume. The zircon content of the fume is determined by treatment of the hydroxide residue with concentrated hydrofluoric acid (HF). The total zirconia content of the fume is determined by digestion of the hydroxide residue with fuming sulphuric acid (oleum), while the relative amounts of monoclinic and tetragonal zirconia may be found by treatment of the hydroxide residue with 10%w/v HF, which attacks the less stable tetragonal phase. Both X-ray diffraction and particle size analysis were used to validate the steps in the analytical procedure. An explanation of the presence of tetragonal zirconia in the fume is proposed. A greater understanding of the composition of the fume led to the installation of a separator in the company's production line to remove the zircon. Australian Fused Materials (AFM) now produces a vastly superior grade of fume marketed under the code SF-98.

  2. Silica fume latex modified concrete bridge deck overlay.

    Science.gov (United States)

    1997-12-01

    The Oregon Department of Transportation has used either Silica Fume or Latex Modified Concrete (LMC) to lower chloride permeability in bridge deck overlays. On this project a new project combining both silica fume and LMC was used. The overlay was co...

  3. Study of radon transport through concrete modified with silica fume

    International Nuclear Information System (INIS)

    Chauhan, R.P.; Kumar, Amit

    2013-01-01

    The concentration of radon in soil usually varies between a few kBq/m 3 and tens or hundreds of kBq/m 3 depending upon the geographical region. This causes the transport of radon from the soil to indoor environments by diffusion and advection through the pore space of concrete. To reduce indoor radon levels, the use of concrete with low porosity and a low radon diffusion coefficient is recommended. A method of reducing the radon diffusion coefficient through concrete and hence the indoor radon concentration by using silica fume to replace an optimum level of cement was studied. The diffusion coefficient of the concrete was reduced from (1.63 ± 0.3) × 10 −7 to (0.65 ± 0.01) × 10 −8 m 2 /s using 30% substitution of cement with silica fume. The compressive strength of the concrete increased as the silica-fume content increased, while radon exhalation rate and porosity of the concrete decreased. This study suggests a cost-effective method of reducing indoor radon levels. -- Highlights: • Radon diffusion study through silica fume modified concrete was carried out. • Radon diffusion coefficient of concrete decreased with increase of silica fume contents. • Compressive strength increased with increase of silica fume. • Radon exhalation rates and porosity of samples decreased with addition of silica fume. • Radon diffusion coefficient decreased to 2.6% by 30% silica fume substitution

  4. Danish Investigations on Silica Fume Concretes at Elevated Temperatures

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    1992-01-01

    Describes fire tests in which the increased risk of explosive spalling of concrete densified by silica fume was first discovered. Further results are discussed from tests to define appropriate limits of silica fume content and to develop a new concrete for slender column units. Observations...

  5. Studies on acute and chronic toxicity of cadmium to freshwater snail Lymnaea acuminata (Lamarck) with special reference to behavioral and hematological changes.

    Science.gov (United States)

    Dhara, Kishore; Saha, Nimai Chandra; Maiti, Arpan Kumar

    2017-12-01

    Molluscs have long been regarded as promising bioindicator and biomonitoring subjects for heavy metals as molluscs are highly tolerant to heavy metals and exhibit high accumulation in their body. In spite of several previous studies about the impact of cadmium on molluscs, little information exists in literatures concerning the toxic effects of cadmium on Lymnaea acuminata, especially pertaining to behavioral and hematological changes as these are considered effective bioindicators and biomonitoring variables for detecting heavy metals in polluted water bodies. In the present study, the median lethal concentrations of cadmium chloride to snail, Lymnaea acuminata, were estimated to be 9.66, 7.69, 6.26, and 5.54 mg/L at 24, 48, 72, and 96 h, respectively. For behavioral studies, variable test concentrations of cadmium from 0.00 to 10 mg/L were used. The clumping tendency, crawling activity, and touch reflex in the exposed snails were gradually decreased with higher concentrations at 72 and 96 h. For measuring the hemocyte numbers in the circulating hemolymph of snail during chronic cadmium exposure, two sublethal doses of cadmium (10 and 20% 96-h LC 50 -0.55 and 1.11 mg/L, respectively) were used. A significant variation (p < 0.05) from the control at all exposure times (7, 14, 21, and 28 days) was recorded at 1.11 mg/L concentration. The total count of circulating hemocytes was significantly reduced (p < 0.05) compared to the controls at both concentrations of cadmium exposure at all time periods except 14 and 21 days exposure at 0.55 mg/L where values were non-significantly increased. In comparison between two sublethal doses, blood cells were significantly (p < 0.05) lowered at 1.11 mg/L cadmium treatment. Considering the behavioral and hematological data, it seems possible to forecast the physiological state of snails in cadmium-contaminated water bodies and these findings can be used in determining the safe disposal level of cadmium in aquatic

  6. Toxic fumes from explosives: ammonium nitrate-fuel oil mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Chaiken, R.F.; Cook, E.B.; Ruhe, T.C.

    1974-01-01

    The Bureau of Mines has carried out experimental and theoretical studies with prilled and pulverized ammonium nitrate-fuel oil (AN-FO) mixtures containing varying amounts of fuel oil in an attempt to quantify the effects of stoichiometric composition, nonideal detonation behavior, and expansion volume on the production of CO, NO, and NO/sub 2/ fumes. Experimental fume measurements were obtained in the Bureau's large closed gallery facility (7.2 x 10/sup 4/ liter expansion chamber) and in the standard Crawshaw-Jones apparatus (90-liter expansion chamber) using a prepackaged charge configuration containing about 450 g of explosives. The theoretical calculation of toxic fumes was achieved with an equilibrium detonation code called TIGER. Contrary to initial expectations, the NO/sub x/ (= NO + NO/sub 2/) fumes from the large gallery test were found to be in essential agreement with the Crawshaw-Jones results. It was also concluded that TIGER calculations offer a good approach to the prediction of toxic fumes; there is a basic problem in extrapolating laboratory measurements of CO fumes to mine conditions, this being due to postdetonation oxidation of CO to CO/sub 2/; and the detonation velocity decay rate of an explosive is a useful experimental parameter for correlating toxic fumes production with nonideal detonation behavior.

  7. [Analysis on oil fume particles in catering industry cooking emission].

    Science.gov (United States)

    Tan, De-Sheng; Kuang, Yuan-Cheng; Liu, Xin; Dai, Fei-Hong

    2012-06-01

    By measuring the particulate matter of oil fume which is over 10 microm or below 10 microm separately and using microradiography and Electrical Low Pressure Impactor (ELPI), it is found out the distributing characteristic of oil fume particles in catering industry cooking emission. The result shows that the diameter of the oil fume particles which was sedimentated in the kitchen is between 10-400 microm, the concentration peak value is between 10-100 microm. The diameter of oil fume aerosol is mostly smaller than 1 microm, while the concentration peak value is between 0.063-0.109 microm. In addition, the mass concentration peak value is between 6.560-9.990 microm. Through the analysis to the physical characteristics of oil fume from catering industry cooking emissions, the eigenvalue of the oil fume has been found and the feature matter for monitoring the oil fume has been discovered to provide a reasonable standard for controlling and monitoring the catering industry cooking emission.

  8. Welding-fume-induced transmission loss in tapered optical fibers

    Science.gov (United States)

    Yi, Ji-Haeng

    2015-09-01

    This paper presents a method for sensing welding fumes in real time. This method is based on the results of nanoparticle-induced optical-fiber loss experiments that show that the losses are determined by the nanoparticle density and the taper waist. The tapered fiber is obtained by applying heat radiated from hot quartz, and monitoring is done in real time. First, the durability of the tapered fiber during the welding process is proven. Then, the loss is categorized by using the sizes of welding fume particles. The sensitivity to welding fumes increases with increasing size of the particles; consequently, the dimension of the taper waist decreases.

  9. Cadmium and the kidney.

    OpenAIRE

    Friberg, L

    1984-01-01

    The paper is a review of certain aspects of importance of cadmium and the kidney regarding the assessment of risks and understanding of mechanisms of action. The review discusses the following topics: history and etiology of cadmium-induced kidney dysfunction and related disorders; cadmium metabolism, metallothionein and kidney dysfunction; cadmium in urine as indicator of body burden, exposure and kidney dysfunction; cadmium levels in kidney and liver as indicators of kidney dysfunction; cha...

  10. Immunotoxicology of arc welding fume: Worker and experimental animal studies

    Science.gov (United States)

    Zeidler-Erdely, Patti C.; Erdely, Aaron; Antonini, James M.

    2015-01-01

    Arc welding processes generate complex aerosols composed of potentially hazardous metal fumes and gases. Millions of workers worldwide are exposed to welding aerosols daily. A health effect of welding that is of concern to the occupational health community is the development of immune system dysfunction. Increased severity, frequency, and duration of upper and lower respiratory tract infections have been reported among welders. Specifically, multiple studies have observed an excess mortality from pneumonia in welders and workers exposed to metal fumes. Although several welder cohort and experimental animal studies investigating the adverse effects of welding fume exposure on immune function have been performed, the potential mechanisms responsible for these effects are limited. The objective of this report was to review both human and animal studies that have examined the effect of welding fume pulmonary exposure on local and systemic immune responses. PMID:22734811

  11. Immunotoxicology of arc welding fume: worker and experimental animal studies.

    Science.gov (United States)

    Zeidler-Erdely, Patti C; Erdely, Aaron; Antonini, James M

    2012-01-01

    Arc welding processes generate complex aerosols composed of potentially hazardous metal fumes and gases. Millions of workers worldwide are exposed to welding aerosols daily. A health effect of welding that is of concern to the occupational health community is the development of immune system dysfunction. Increased severity, frequency, and duration of upper and lower respiratory tract infections have been reported among welders. Specifically, multiple studies have observed an excess mortality from pneumonia in welders and workers exposed to metal fumes. Although several welder cohort and experimental animal studies investigating the adverse effects of welding fume exposure on immune function have been performed, the potential mechanisms responsible for these effects are limited. The objective of this report was to review both human and animal studies that have examined the effect of welding fume pulmonary exposure on local and systemic immune responses.

  12. Investigation of silica fume concrete bridge deck overlay failures.

    Science.gov (United States)

    2016-02-23

    Many of these microsilica-modified concrete or silica fume concrete (SFC) bridge deck overlays across the State of Wyoming are suffering from premature distress that includes random cracking, loss of bond and delaminations. To determine the most like...

  13. Welding fume exposure and chronic obstructive pulmonary disease in welders.

    Science.gov (United States)

    Koh, D-H; Kim, J-I; Kim, K-H; Yoo, S-W

    2015-01-01

    Occupational exposure is estimated to contribute 15% to the burden of chronic obstructive pulmonary disease (COPD). Welding fumes are suspected to accelerate the decline of lung function and development of COPD. To examine the relationship between welding fume exposure and COPD in Korean shipyard welders. The study involved a group of male welders working at two shipyards who underwent an annual health examination in 2010. Subjects completed a questionnaire about smoking habits and occupational history and a pulmonary function test (PFT) was carried out with strict quality control measures. Welding fume exposure concentrations were estimated using 884 measurements taken between 2002 and 2009 in one of the shipyards. Multiple linear and logistic regression was employed to evaluate the association between cumulative fume exposure and lung function parameters, controlling for age, height and cigarette smoking. Two hundred and forty subjects participated, with a mean age of 48 and mean work duration of 15 years. The mean cumulative fume exposure was 7.7mg/m(3). The prevalence of COPD was 15%. FEV1 and FVC showed non-significant negative correlations with cumulative fume exposure. Odds ratios of COPD were significantly elevated for the middle (3.9; 95% CI 1.4-13.3) and high exposure groups (3.8; 95% CI 1.03-16.2) compared with the low fume exposure group. Our findings support an association between welding fume exposure and increased risk of COPD. Further prospective study is needed to investigate whether this is a causal relationship. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Short term exposure to cooking fumes and pulmonary function

    OpenAIRE

    Qvenild Torgunn; Svendsen Kristin; Svedahl Sindre; Sjaastad Ann; Hilt Bjørn

    2009-01-01

    Abstract Background Exposure to cooking fumes may have different deleterious effects on the respiratory system. The aim of this study was to look at possible effects from inhalation of cooking fumes on pulmonary function. Methods Two groups of 12 healthy volunteers (A and B) stayed in a model kitchen for two and four hours respectively, and were monitored with spirometry four times during twenty four hours, on one occasion without any exposure, and on another with exposure to controlled level...

  15. Analysis of polycyclic aromatic hydrocarbons in cooking oil fumes.

    Science.gov (United States)

    Li, S; Pan, D; Wang, G

    1994-01-01

    Various samples of cooking oil fumes were analyzed to an effort to study the relationship between the high incidence of pulmonary adenocarcinoma in Chinese women and cooking oil fumes in the kitchen. Polycyclic aromatic hydrocarbons (PAHs) in samples of cooking oil fumes were extracted, chromatographed, and measured by fluorescence spectrophotometer. The samples included oil fumes from three commercial cooking oils and fumes from three catering shops. All samples contained benzo(a)pyrene (BaP) and dibenzo (a,h)anthracene (DBahA). In addition, the concentration of DBahA was 5.7 to 22.8 times higher than that of BaP in the fume samples. Concentrations of BaP and DBahA were, respectively, 0.463 and 5.736 micrograms/g in refined vegetable oil, 0.341 and 3.725 micrograms/g in soybean oil, and 0.305 and 4.565 micrograms/g in vegetable oil. Investigation of PAH concentrations at three catering shops showed that the level of BaP at a Youtiao (deep-fried twisted dough sticks) shop was 4.18 micrograms/100 m3, 2.28 micrograms/100 m3 at a Seqenma (candied fritters) workshop, and 0.49 micrograms/100 m3 at a kitchen of a restaurant; concentrations of DBahA were 33.80, 14.41, and 3.03 micrograms/100 m3, respectively. The high concentration of carcinogens, such as BaP and DBahA, in cooking oil fumes might help explain why Chinese women, who spend more time exposed to cooking oil fumes than men, have a high incidence of pulmonary adenocarcinoma.

  16. Peripheral neuropathy following intentional inhalation of naphtha fumes.

    OpenAIRE

    Tenenbein, M; deGroot, W; Rajani, K R

    1984-01-01

    Two adolescent native Canadians who presented with peripheral neuropathy secondary to the abuse of volatile hydrocarbons are described. They were initially thought to have been sniffing leaded gasoline fumes, but public health investigation revealed that they had been sniffing naphtha fumes. Naphtha contains a significant amount of n-hexane, a known inducer of neuropathy. Nerve conduction studies and nerve biopsy confirmed the diagnosis of naphtha abuse. These cases emphasize the need to spec...

  17. Lifetime occupational exposure to metals and welding fumes, and risk of glioma: a 7-country population-based case-control study.

    Science.gov (United States)

    Parent, Marie-Elise; Turner, Michelle C; Lavoué, Jérôme; Richard, Hugues; Figuerola, Jordi; Kincl, Laurel; Richardson, Lesley; Benke, Geza; Blettner, Maria; Fleming, Sarah; Hours, Martine; Krewski, Daniel; McLean, David; Sadetzki, Siegal; Schlaefer, Klaus; Schlehofer, Brigitte; Schüz, Joachim; Siemiatycki, Jack; van Tongeren, Martie; Cardis, Elisabeth

    2017-08-25

    Brain tumor etiology is poorly understood. Based on their ability to pass through the blood-brain barrier, it has been hypothesized that exposure to metals may increase the risk of brain cancer. Results from the few epidemiological studies on this issue are limited and inconsistent. We investigated the relationship between glioma risk and occupational exposure to five metals - lead, cadmium, nickel, chromium and iron- as well as to welding fumes, using data from the seven-country INTEROCC study. A total of 1800 incident glioma cases and 5160 controls aged 30-69 years were included in the analysis. Lifetime occupational exposure to the agents was assessed using the INTEROCC JEM, a modified version of the Finnish job exposure matrix FINJEM. In general, cases had a slightly higher prevalence of exposure to the various metals and welding fumes than did controls, with the prevalence among ever exposed ranging between 1.7 and 2.2% for cadmium to 10.2 and 13.6% for iron among controls and cases, respectively. However, in multivariable logistic regression analyses, there was no association between ever exposure to any of the agents and risk of glioma with odds ratios (95% confidence intervals) ranging from 0.8 (0.7-1.0) for lead to 1.1 (0.7-1.6) for cadmium. Results were consistent across models considering cumulative exposure or duration, as well as in all sensitivity analyses conducted. Findings from this large-scale international study provide no evidence for an association between occupational exposure to any of the metals under scrutiny or welding fumes, and risk of glioma.

  18. Acute toxicity of copper, lead, cadmium, and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water.

    Science.gov (United States)

    Vardy, David W; Santore, Robert; Ryan, Adam; Giesy, John P; Hecker, Markus

    2014-01-01

    Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9-25 μg Cu/L and 177-1,556 μg Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 μg/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 μg/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed

  19. Assessment and management of risk to wildlife from cadmium

    International Nuclear Information System (INIS)

    Burger, Joanna

    2008-01-01

    Cadmium, a nonessential heavy metal that comes from natural and anthropogenic sources, is a teratogen, carcinogen, and a possible mutagen. Assessment of potential risk from cadmium requires understanding environmental exposure, mainly from ingestion, although there is some local exposure through inhalation. Chronic exposure is more problematic than acute exposure for wildlife. There is evidence for bioaccumulation, particularly in freshwater organisms, but evidence for biomagnification up the food chain is inconsistent; in some bird studies, cadmium levels were higher in species that are higher on the food chain than those that are lower. Some freshwater and marine invertebrates are more adversely affected by cadmium exposure than are birds and mammals. There is very little experimental laboratory research on the effects of cadmium in amphibians, birds and reptiles, and almost no data from studies of wildlife in nature. Managing the risk from cadmium to wildlife involves assessment (including ecological risk assessment), biomonitoring, setting benchmarks of effects, regulations and enforcement, and source reduction

  20. Environmental exposure to cooking oil fumes and cervical intraepithelial neoplasm

    International Nuclear Information System (INIS)

    Wu, M.-T.; Lee, L.-H.; Ho, C.-K.; Wu, S.-C.; Lin, L.-Y.; Cheng, B.-H.; Liu, C.-L.; Yang, C.-Y.; Tsai, H.-T.; Wu, T.-N.

    2004-01-01

    The fumes from cooking oil, similar to cigarette smoke, contain numerous carcinogens such as polycyclic aromatic hydrocarbons, aromatic amines, nitro-polycyclic aromatic hydrocarbons, etc. In this study, we examined the association between exposure to cooking oil fumes and the risk of cervical intraepithelial neoplasm. The study population in this nested case-control study consisted of women above the age of 19 years living in Chia-Yi County, located in the southwestern Taiwan, who had received pap smear screening between October, 1999, and December, 2000 (n=32,466). The potential cases were women having lesions greater than cervical intraepithelium neoplasm II (≥CIN2) reconfirmed by cervical biopsy (n=116). The potential controls (case: control=1:2) were age-matched (±2 years) and residence-matched women who had normal pap smears within 6 months of the cases. In total, 100 cases and 197 controls were completely interviewed by public health nurses about cooking methods, ventilation, and other potential risk factors. Women who cooked at home in a kitchen (n=269) without the presence of a fume extractor at least once a week between the ages of 20 and 40 had a 2.29 times higher risk [95% confidence interval (CI)=1.08-4.87] of developing cervical intraepithelial neoplasm than those who did not cook once a week in such a kitchen during the same age span, after adjusting for other potential confounders. This finding was further strengthened by the finding that women who did not use the fume extractors had a 2.47 times higher risk (95% CI=1.15-5.32) of developing cervical intraepithelial neoplasm than women who cooked in kitchens with fume extractors that were always switched on while cooking. We also found a joint protective effect of fume extractor use among women older than 40 years (n=202) if they used the extractors during both age spans of their lives, ages 20-40 and >40 years. Comparing our findings on women more than 40 years old who used fume extractors during

  1. Short term exposure to cooking fumes and pulmonary function

    Directory of Open Access Journals (Sweden)

    Qvenild Torgunn

    2009-05-01

    Full Text Available Abstract Background Exposure to cooking fumes may have different deleterious effects on the respiratory system. The aim of this study was to look at possible effects from inhalation of cooking fumes on pulmonary function. Methods Two groups of 12 healthy volunteers (A and B stayed in a model kitchen for two and four hours respectively, and were monitored with spirometry four times during twenty four hours, on one occasion without any exposure, and on another with exposure to controlled levels of cooking fumes. Results The change in spirometric values during the day with exposure to cooking fumes, were not statistically significantly different from the changes during the day without exposure, with the exception of forced expiratory time (FET. The change in FET from entering the kitchen until six hours later, was significantly prolonged between the exposed and the unexposed day with a 15.7% increase on the exposed day, compared to a 3.2% decrease during the unexposed day (p-value = 0.03. The same tendency could be seen for FET measurements done immediately after the exposure and on the next morning, but this was not statistically significant. Conclusion In our experimental setting, there seems to be minor short term spirometric effects, mainly affecting FET, from short term exposure to cooking fumes.

  2. Comparison of Effect of Metakaolin and silica Fume on Fly Ash Concrete Performance

    Directory of Open Access Journals (Sweden)

    Hou Yunfen

    2016-01-01

    Full Text Available Silica fume is a common mineral admixture used in HSC and HPC, but being its high price and shrinkage in concrete, its usage is under restrictions. As a new mineral admixture, metakaolin gets more and more attention. In order to compare the difference between silica fume and metakaolin, the effects of metakaolin and silica fume on concrete workability, compressive strength, and chloride penetration resistance are studied. It shows that incorporating with fly ash together, silica fume reduces the slump extension, but metakaolin can increases it; silica fume can increases early strength more than metakaolin can, but it isn’t useful for later and long-time strength; metakaolin not only can increase early strength, but also can improve long-time strength. Silica fume and metakaolin can increase the chloride penetration resistance. As a new mineral additive, metakaolin can play a role in concrete which silica fume does, even much better than silica fume.

  3. 42 CFR 84.1140 - Dust, fume, and mist respirators; performance requirements; general.

    Science.gov (United States)

    2010-10-01

    ... PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1140 Dust, fume, and mist respirators; performance requirements...

  4. ( Rattus norvegicus ) Fed with Dietary Cadmium

    African Journals Online (AJOL)

    Histological changes in the kidney tissues of albino rats (Rattus norvegicus) fed 100mg/kg body weight of cadmium sulphate incorporated as food material has been studied in vivo in an acute toxicological experiment. The behavioural pattern and physical changes in the rats were also investigated. Loss of weight and ...

  5. Calcium enhances cadmium tolerance and decreases cadmium ...

    African Journals Online (AJOL)

    We aimed at characterizing mechanisms controlling cadmium accumulation in lettuce, which is a food crop showing one of the highest capacities to accumulate this toxic compound. In this study, plants from three lettuce varieties were grown for eight days on media supplemented or not with cadmium (15 μM CdCl2) and ...

  6. Silica fume effect on retention characteristics of portland cement for uranium (VI)

    International Nuclear Information System (INIS)

    Tan Hongbin; Ma Xiaoling; Li Yuxiang

    2005-01-01

    With simulated groundwater as leachant, the retention capabilities of the portland cement, which contains different amount of silica fume, are investigated under 25 degree C and 42 days. The results indicate that silica fume can improve the retention capabilities of portland cement for uranium. When the cement contains 15% silica fume, the diffusion coefficient is 7 x 10 -3 cm 3 · -1 . It is only 5.5% of the cement without containing fume. (authors)

  7. Urinary β2 Microglobulin in Workers Exposed to Arc Welding Fumes

    Directory of Open Access Journals (Sweden)

    Khosro Sadeghniiat-Haghighi

    2011-11-01

    Full Text Available Welding is a process in which two or more metals are attached by the use of heat and, in some cases, pressure. Direct exposure and inhalation of welding fumes causes acute and chronic side effects in humans. Kidney damage is one of these important side effects. β2 microglobulin is an 11.8 kilodalton protein and levels increase in the case of some inflammatory and viral diseases, or kidney malfunction and autoimmune diseases. In this study measurements of β2 microglobulin were used as a criterion for assessing effects on the kidneys of workers exposed to welding fumes. The study population were electric arc welders in an industrial plant in Tehran, Iran. For control we selected workers who did not have any exposure to welding fumes. Both groups were selected on the basis of a questionnaire and the consideration of criteria for inclusion and exclusion. In the end 50 cases and 50 controls were chosen. A urine sample was collected from all participants and urinary pH was set to between 6-8 using NaOH (1M. Sample transportation to the laboratory complied with the related standards. The samples were assessed using the ORG 5BM kit. For quantitative assessment of β2 microglobulin we used the Enzyme-linked Immunosorbent Assay (ELISA method. The ages of the welders ranged from 21 to 48 years (mean=30.5±5.9 yrs and of controls from 23 to 56 years (mean=31.8±5.9 yrs. Mean employment duration was 7.86±5.01years (range 2 to 27 years for welders. Mean β2 microglobulin level was 0.10±0.096 μg/ml in welders and 0.11±0.06 in controls. This difference was not statistically significant (P=0.381. In conclusion we don't find that exposure to electric arc welding fumes cause a significant change in urinary β2 microglobulin compared to the control group.

  8. Urinary β2 microglobulin in workers exposed to arc welding fumes.

    Science.gov (United States)

    Aminian, Omid; Eftekhari, Saeid; Mazaheri, Maria; Sharifian, Seyed Akbar; Sadeghniiat-Haghighi, Khosro

    2011-01-01

    Welding is a process in which two or more metals are attached by the use of heat and, in some cases, pressure. Direct exposure and inhalation of welding fumes causes acute and chronic side effects in humans. Kidney damage is one of these important side effects. β(2) microglobulin is an 11.8 kilodalton protein and levels increase in the case of some inflammatory and viral diseases, or kidney malfunction and autoimmune diseases. In this study measurements of β(2) microglobulin were used as a criterion for assessing effects on the kidneys of workers exposed to welding fumes. The study population were electric arc welders in an industrial plant in Tehran, Iran. For control we selected workers who did not have any exposure to welding fumes. Both groups were selected on the basis of a questionnaire and the consideration of criteria for inclusion and exclusion. In the end 50 cases and 50 controls were chosen. A urine sample was collected from all participants and urinary pH was set to between 6-8 using NaOH (1M). Sample transportation to the laboratory complied with the related standards. The samples were assessed using the ORG 5BM kit. For quantitative assessment of β(2) microglobulin we used the Enzyme-linked Immunosorbent Assay (ELISA) method. The ages of the welders ranged from 21 to 48 years (mean=30.5 ± 5.9 yrs) and of controls from 23 to 56 years (mean=31.8 ± 5.9 yrs). Mean employment duration was 7.86 ± 5.01 years (range 2 to 27 years) for welders. Mean β(2) microglobulin level was 0.10 ± 0.096 μg/ml in welders and 0.11 ± 0.06 in controls. This difference was not statistically significant (P=0.381). In conclusion we don't find that exposure to electric arc welding fumes cause a significant change in urinary β(2) microglobulin compared to the control group.

  9. 42 CFR 84.1158 - Dust, fume, and mist tests; respirators with filters; minimum requirements; general.

    Science.gov (United States)

    2010-10-01

    ... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1158 Dust, fume, and mist tests..., the maximum allowable resistance of complete dust, fume, and mist, and gas, vapor, or gas and vapor...

  10. 42 CFR 84.1149 - Airflow resistance tests; all dust, fume, and mist respirators; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1149 Airflow resistance tests; all dust, fume, and mist..., hood, or helmet of a dust, fume, or mist respirator mounted on a test fixture with air flowing at a...

  11. Pulmonary fibrosis and exposure to steel welding fume.

    Science.gov (United States)

    Cosgrove, M P

    2015-12-01

    Arc welders who have been exposed to high concentrations of steel welding fume for prolonged periods of time may develop pulmonary fibrosis but the nature of the fibrotic changes has been debated over the last 80 years without any clear international consensus. To characterize the nature of the pulmonary fibrosis that develops in response to steel welding fume exposure and to provide a working hypothesis that would explain the findings of the existing research, to provide a platform for future research and to inform future occupational and clinical management of welders with pulmonary effects from welding fume. Review of the world literature on pulmonary fibrosis and welding of steel in all languages using PubMed, with further secondary search of references in the articles found in the primary search. Google and Reference Manager were used as further confirmatory search tools. Only case series and case reports were found but these provided consistent evidence that the consequence of exposure to steel welding fume at high levels for a prolonged period of time is a type of pulmonary fibrosis similar to, and possibly the same as, respiratory bronchiolitis which eventually develops into desquamative interstitial pneumonia with ongoing exposure. Steel welding fume may cause an occupational respiratory bronchiolitis which may develop into de squamative interstitial pneumonia with ongoing exposure. This concept may explain the difficulties in interpreting the wider literature on welding fume and lung function at lower exposures and may also explain the increased risk of lung cancer in welders. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. TOXIC EFFECTS OF CADMIUM

    Directory of Open Access Journals (Sweden)

    Tanja Vukićević

    2012-01-01

    Full Text Available Cadmium is one of the heavy metals, it is often used in industry, and exerts toxic effects on human health. Cadmium is classified as a carcinogenic substance for humans by the International Agency for Research on Cancer and is in a group I carcinogen. Cadmium affects the development of cell cycle, proliferation, differentiation, DNA repair, replication and apoptosis, as well as promotion of cancer in tissues. Intoxication with cadmium in people usually occurs by inhalation of cigarette smoke, but it is also possible via water, food and air. Cadmium exerts toxic effects on the kidneys, liver, lungs, cardiovascular system, immune system and reproductive system. Metallothionein protects tissues from the toxicity of cadmium. Cadmium-metallothionein complex is distributed in various tissues. There is no way for natural cadmium elimination from the human body. The main route of cadmium in the body is through binding with metallothionein, low molecular weight protein that participates in the homeostasis of certain metals. Cadmium-metallothionein complex is distributed in various tissues. The role of metallothionein in detoxification of cadmium is primarily in the large binding affinity of metals for metallothionein.

  13. Risk of ischemic heart disease following occupational exposure to welding fumes: a systematic review with meta-analysis.

    Science.gov (United States)

    Mocevic, Emina; Kristiansen, Pernille; Bonde, Jens Peter

    2015-04-01

    Air pollution has been linked to an increased risk of ischemic heart disease (IHD), but less is known about occupational exposure to welding fumes and the risk of IHD. The objective of this paper was to review the epidemiological evidence on causal links between welding fume exposure and risk of IHD and to investigate whether the risk of IHD depends on specific welding characteristics. A systematic search in Medline 1979-2013 and EMBASE 1974-2013 identified 18 epidemiological studies with at least one risk estimate of IHD morbidity or mortality among workers exposed to welding fumes. Following an assessment of completeness of reporting, confounding, and bias, each risk estimate was characterized as more or less reliable. Pooled risk estimates were computed across studies by random effect meta-analyses. The weighted relative risk (RR) for IHD following exposure to welding fumes was 1.09 [95 % confidence interval (CI) 1.00, 1.19]. We calculated a RR of 1.39 (95 % CI 0.96, 2.02) among studies using an internal reference group and 1.08 (95 % CI 0.99, 1.18) for studies using an external reference group. An increased risk was observed for acute myocardial infarction RR = 1.69 (95 % CI 1.18, 2.42) and other IHDs RR = 1.06 (95 % CI 0.98, 1.14). There was too limited evidence to evaluate the risk of IHD related to specific welding characteristics. Several studies indicate that welding is associated with a moderately increased risk of IHD; however, bias and confounding cannot be ruled out with reasonable confidence.

  14. Acute toxicity of copper and cadmium for piauçu, Leporinus macrocephalus, and curimatã, Prochilodus vimboides - DOI: 10.4025/actascibiolsci.v31i3.5069 Acute toxicity of copper and cadmium for piauçu, Leporinus macrocephalus, and curimatã, Prochilodus vimboides - DOI: 10.4025/actascibiolsci.v31i3.5069

    Directory of Open Access Journals (Sweden)

    Luis Fernando Loureiro Fernandes

    2009-07-01

    Full Text Available Ninety-six-hour static bioassays were conducted in the laboratory to determine lethal concentrations (96-h LC50 of copper and cadmium for curimatã (Prochilodus vimboides and piauçu (Leporinus macrocephalus. The 96-h LC50 of copper were 0.047 and 0.090 mg L-1, and of cadmium 3.16 and 7.42 mg L-1 for curimatã and piauçu, respectively. Curimatã is a preferred indigenous species for toxicological studies in the Doce River basin due to its availability in the hatcheries of the region and high sensitivity to metals.Ninety-six-hour static bioassays were conducted in the laboratory to determine lethal concentrations (96-h LC50 of copper and cadmium for curimatã (Prochilodus vimboides and piauçu (Leporinus macrocephalus. The 96-h LC50 of copper were 0.047 and 0.090 mg L-1, and of cadmium 3.16 and 7.42 mg L-1 for curimatã and piauçu, respectively. Curimatã is a preferred indigenous species for toxicological studies in the Doce River basin due to its availability in the hatcheries of the region and high sensitivity to metals.

  15. Exposure to inhalable, respirable, and ultrafine particles in welding fume.

    Science.gov (United States)

    Lehnert, Martin; Pesch, Beate; Lotz, Anne; Pelzer, Johannes; Kendzia, Benjamin; Gawrych, Katarzyna; Heinze, Evelyn; Van Gelder, Rainer; Punkenburg, Ewald; Weiss, Tobias; Mattenklott, Markus; Hahn, Jens-Uwe; Möhlmann, Carsten; Berges, Markus; Hartwig, Andrea; Brüning, Thomas

    2012-07-01

    This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m(-3) for inhalable and 1.29 mg m(-3) for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m(-3)). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements welding fume. Concentrations were mainly predicted by the welding process and were significantly higher when local exhaust ventilation (LEV) was inefficient or when welding was performed in confined spaces. Substitution of high-emission techniques like FCAW, efficient LEV, and using PAPRs where applicable can reduce exposure to welding fume. However, harmonizing the different exposure metrics for UFP (as particle counts) and for the respirable or inhalable fraction of the welding fume (expressed as their mass) remains challenging.

  16. Hepatotoxic and Nephrotoxic Effects of Petroleum Fumes on Petrol ...

    African Journals Online (AJOL)

    The present study was conducted to evaluate the hepatotoxic and nephrotoxic effects of petroleum fumes on male and female petrol attendants. Investigations had been carried out on thirty (30) adult petrol attendants from different filling stations in Ibadan metropolis of Nigeria with ten (10) healthy adults as control. All the ...

  17. Effect of Generator (Exhaust) Fumes on the Growth and ...

    African Journals Online (AJOL)

    PROF HORSFALL

    ABSTRACT: The effects of generator (Exhaust) Fumes on the growth and development of. Lycopersicum esculentus were evaluated in this study. It involved sowing ten seeds of L. esculentus in plastic pots. These were allowed to germinate and stabilize for two weeks after which they were exposed to 0.75KVA generator ...

  18. Pemanfaatan Mikrobakteri Terhadap Beton Mutu Tinggi dengan Tambahan Silica Fume

    Directory of Open Access Journals (Sweden)

    Azwar Annas

    2016-04-01

    Full Text Available Beton mutu tinggi adalah beton yang kuat tekan tinggi sekitar 50 MPa – 100 MPa. Untuk meningkatkan kuat tekan, material pozollan seperti silica fume dan flyash biasanya digunakan untuk mengganti material beton Dalam laporan ini, beton mutu tinggi dengan silica fume sebagai pengganti semen dipelajari. Kadar silica fume yang digunakan adalah 0%, 5%, 7,5% dan 10%. Selain itu pengaruh dari mikrobakteri juga dipelajari. Faktor water per binder yang dipakai adalah 25% dari berat binder, dan untuk membuat workabilitynya bagus maka digunakan superplasticizer. Kadar superplasticizer yang digunakan dicari lewat trial pengujian di laboratorium. Pengujian yang dilakukan pada umur 1, 3, 7, 14, 21, 28 adalah uji tekan pasta, mortar dan beton, selain itu pada benda uji beton umur 28 hari akan dilakukan uji split beton dan uji porositas. Dari hasil penelitian didapatkan kuat tekan beton tertinggi pada umur 28 hari (B7,5M adalah 69,71 MPa, sedangkan variasi silica fume yang paling optimum ada pada kadar 7,5%. Penambahan mikrobakteri tidak berpengaruh pada berat volume beton tetapi berpengaruh pada kuat tekan beton tersebut. Dengan penambahan mikrobakteri maka kuat tekan beton meningkat sebesar ± 30%. Sedangkan porositas total dan porositas tertutup yang terjadi pada beton semakin kecil, ini dibuktikan dengan hasil SEM terlihat bahwa bakteri mengisi area antara aggregat dan matrix beton.

  19. EFFECTS OF FIRE FUMES ON ALMOND SAFETY AND QUALITY

    Directory of Open Access Journals (Sweden)

    Amanda Ramírez-Gandolfo

    2011-08-01

    Full Text Available A fire originated and burnt two cold chambers; the present study focused on almonds stored in adjacent chambers (4, 5, 6 and 13 and evaluated both their food safety and quality. Testing for polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans was carried out in affected facilities, packaging and almonds. Experimental results proved that fire fumes did not reach chambers 4-6, but traces were found in bin packaging of chamber 13; thus, packaging from this chamber were changed. Concentrations of benzo(apyrene were low enough to prove that fire fumes did not get in contact with the stored almonds. Later, only volatile compounds typical of nuts were identified in both raw and toasted almonds. Finally, a trained panel concluded that no sensory signal of fumes reaching almonds was found. This manuscript could be taken as a model protocol to establish whether fire fumes have reached and affected the safety and/or quality of foods. This information will be especially useful for insurance companies.

  20. 28 The Theatre and Sustainable Human Development: Fumes of ...

    African Journals Online (AJOL)

    audience composed of persons saddled with the responsibility of showing the direction for the development of a certain society. This paper will use the plays, Fumes of Fuel and Boundless Love to expound on the relevance of the Performing Arts in human and societal development. Keywords: Performing Arts, Creativity, ...

  1. Reaction products of densified silica fume agglomerates in concrete

    International Nuclear Information System (INIS)

    Diamond, Sidney; Sahu, Sadananda; Thaulow, Niels

    2004-01-01

    Most silica fume currently used in concrete is in the dry densified form and consists of agglomerates of sizes between 10 μm and several millimeters. Many of these agglomerates may break down only partially in normal concrete mixing. Examination of various mature silica-fume-bearing concretes using backscatter mode scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis shows that such agglomerates have reacted in situ and given rise to recognizable types of reaction products filling the space within the original outline of the agglomerate. One type is 'quiescent', and usually shows no evidence of volume instability. EDX spectra indicate that the product formed within such grains is C-S-H of very low Ca/Si ratio, with modest alkali contents. Other silica fume agglomerates may undergo a distinct alkali-silica-type reaction (ASR), with the reaction product found within the original outline of the agglomerate having significantly less calcium and usually much higher alkali contents than the quiescent type. Such reacted agglomerates show evidence of local expansion, shrinkage cracking (on drying), and other features common to ASR. Both types may be found within the same concrete, sometimes in close proximity. It further appears that exposure to seawater may convert previously formed reaction products of silica fume agglomerates to magnesium silicate hydrates

  2. Effect of plasticizer and fumed silica on ionic conductivity behaviour

    Indian Academy of Sciences (India)

    The effect of addition of propylene carbonate (PC) and nano-sized fumed silica on the ionic conductivity behaviour of proton conducting polymer electrolytes containing different concentrations of hexafluorophosphoric acid (HPF6) in polyethylene oxide (PEO) has been studied. The addition of PC results in an increase in ...

  3. Effect of plasticizer and fumed silica on ionic conductivity behaviour ...

    Indian Academy of Sciences (India)

    The effect of addition of propylene carbonate (PC) and nano-sized fumed silica on the ionic conductivity behaviour of proton conducting polymer electrolytes containing different concentrations of hexafluorophosphoric acid (HPF6) in polyethylene oxide (PEO) has been studied. The addition of PC results in an increase in ...

  4. Reduction of Biomechanical and Welding Fume Exposures in Stud Welding.

    Science.gov (United States)

    Fethke, Nathan B; Peters, Thomas M; Leonard, Stephanie; Metwali, Mahmoud; Mudunkotuwa, Imali A

    2016-04-01

    The welding of shear stud connectors to structural steel in construction requires a prolonged stooped posture that exposes ironworkers to biomechanical and welding fume hazards. In this study, biomechanical and welding fume exposures during stud welding using conventional methods were compared to exposures associated with use of a prototype system that allowed participants to weld from an upright position. The effect of base material (i.e. bare structural beam versus galvanized decking) on welding fume concentration (particle number and mass), particle size distribution, and particle composition was also explored. Thirty participants completed a series of stud welding simulations in a local apprenticeship training facility. Use of the upright system was associated with substantial reductions in trunk inclination and the activity levels of several muscle groups. Inhalable mass concentrations of welding fume (averaged over ~18 min) when using conventional methods were high (18.2 mg m(-3) for bare beam; 65.7 mg m(-3) for through deck), with estimated mass concentrations of iron (7.8 mg m(-3) for bare beam; 15.8 mg m(-3) for through deck), zinc (0.2 mg m(-3) for bare beam; 15.8 mg m(-3) for through deck), and manganese (0.9 mg m(-3) for bare beam; 1.5 mg m(-3) for through deck) often exceeding the American Conference of Governmental Industrial Hygienists Threshold Limit Values (TLVs). Number and mass concentrations were substantially reduced when using the upright system, although the total inhalable mass concentration remained above the TLV when welding through decking. The average diameters of the welding fume particles for both bare beam (31±17 nm) through deck conditions (34±34 nm) and the chemical composition of the particles indicated the presence of metallic nanoparticles. Stud welding exposes ironworkers to potentially high levels of biomechanical loading (primarily to the low back) and welding fume. The upright system used in this study improved exposure

  5. Reduction of fume damage in forests: report on the symposium on fume damage held in Tharandt from 30th September to 2nd October 1965

    Energy Technology Data Exchange (ETDEWEB)

    Daessler, H.G.; Ranft, H.

    1967-01-01

    Summaries are presented of 15 papers, including: extent of variation in fume resistance in Larix and problems of breeding for resistance (Schoenbach); results of research on fume damage on experimental areas in E. Germany (H. Enderlin) (noting differences in resistance to SO/sub 2/ damage of various species of Picea, Pinus, and Abies, varieties of Pseudotsuga taxifolia and provenances of Pinus contorta and Larix spp., effect of fertilizers on resistance, and mass selection of resistant planting stock in practice); resistance of Pinus omorika to fume damage (K.F. Wentzel); chemical and physiological studies on the metabolism of the assimilation organs of conifers affected by SO/sub 2/ (S. Boertitz); basic physiological and phenological studies on the preliminary selection of conifers for SO/sub 2/ resistance (M. Vogl); fertilizer trials in fume-damaged pine stands on Dueben Heath (H. Krauss); insect pests on young pine stands in fume-damaged regions in Poland (Z. Sierpinski); birch and alder pests in industrial regions (Z. Schnaider); management of young fume-damaged spruce stands (E. Pelz); effect of fumes from the potash industry on forest stands in East Germany (E. Ewert); the distribution of injurious substances in leaves (G. Halbwachs); emission of SO/sub 2/ absorbed by spruce needles (J. Materna); and estimating fume damage expected near future power stations (H. Lux).

  6. Zinc and cadmium monosalicylates

    International Nuclear Information System (INIS)

    Kharitonov, Yu.Ya.; Tujebakhova, Z.K.

    1984-01-01

    Zinc and cadmium monosalicylates of the composition MSal, where M-Zn or Cd, Sal - twice deprotonated residue of salicylic acid O-HOC 6 H 4 COOH (H 2 Sal), are singled out and characterized. When studying thermograms, thermogravigrams, IR absorption spectra, roentgenograms of cadmium salicylate compounds (Cd(OC 6 H 4 COO) and products of their thepmal transformations, the processes of thermal decomposition of the compounds have been characterized. The process of cadmium monosalicylate decomposition takes place in one stage. Complete loss of salicylate acido group occurs in the range of 320-460 deg. At this decomposition stage cadmium oxide is formed. A supposition is made that cadmium complex has tetrahedral configuration, at that, each salicylate group plays the role of tetradentate-bridge ligand. The compound evidently has a polymer structure

  7. Cadmium preparation by reduction of zinc-cadmium carbonate

    International Nuclear Information System (INIS)

    Malinowski, Cz.; Malecki, S.; Malchar, B.; Orlicz, J.

    1995-01-01

    The paper presents the investigation results regarding a possibility of selective reduction process of cadmium and zinc carbonates in order to obtain high purity cadmium metallic or cadmium oxide. The reduction tests performed in CO stream and with coke indicated a possibility of a selective course of this process. The results obtained allowed to determine more precisely the temperature conditions of the reduction process so as to attain cadmium or cadmium oxide of purities required. (author)

  8. deFUME: Dynamic exploration of functional metagenomic sequencing data

    DEFF Research Database (Denmark)

    van der Helm, Eric; Geertz-Hansen, Henrik Marcus; Genee, Hans Jasper

    2015-01-01

    Functional metagenomic selections represent a powerful technique that is widely applied for identification of novel genes from complex metagenomic sources. However, whereas hundreds to thousands of clones can be easily generated and sequenced over a few days of experiments, analyzing the data...... is time consuming and constitutes a major bottleneck for experimental researchers in the field. Here we present the deFUME web server, an easy-to-use web-based interface for processing, annotation and visualization of functional metagenomics sequencing data, tailored to meet the requirements of non......-bioinformaticians. The web-server integrates multiple analysis steps into one single workflow: read assembly, open reading frame prediction, and annotation with BLAST, InterPro and GO classifiers. Analysis results are visualized in an online dynamic web-interface. The deFUME webserver provides a fast track from raw sequence...

  9. Pulmonary Adverse Effects of Welding Fume in Automobile Assembly Welders

    Directory of Open Access Journals (Sweden)

    Seyed Akbar Sharifian

    2011-02-01

    Full Text Available Welding is one of the key components of numerous manufacturing industries, which has potential physical and chemical health hazards. Many components of welding fumes can potentially affect the lung function. This study investigates the effects of welding fumes on lung function and respiratory symptoms among welders of an automobile manufacturing plant in Iran. This historical cohort study assesses 43 male welders and 129 office workers by a questionnaire to record demographic data, smoking habits, work history and respiratory symptoms as well as lung function status by spirometry. The average pulmonary function values of welders were lower relative to controls with dose-effect relationship between work duration and pulmonary function impairment. The prevalence of chronic bronchitis was higher in welders than controls. Our findings suggest that welders are at risk for pulmonary disease.

  10. FABRICATION AND CHARACTERIZATION OF POLYIMIDE/POLYETHERSULFONE-FUMED SILICA MIXED MATRIX MEMBRANE FOR GAS SEPARATION

    Directory of Open Access Journals (Sweden)

    A. F. Ismail

    2012-01-01

    Full Text Available This study is performed primarily to investigate the feasibility of fumed silica as inorganic material towards gas separation performance of mixed matrix membrane. In this study, polyimide/polyethersulfone (PES-fumed silica mixed matrix membranes were casted using dry/wet technique. The results from the FESEM, DSC and FTIR analysis confirmed that the structure and physical properties of membrane is influenced by inorganic filler. FESEM’s cross-section view indicated good compatibility between polymer and fumed silica for all of range fumed silica used in this study. The gas separation performance of the mixed matrix membranes with fumed silica were relatively higher compared to that of the neat PI/PES membrane. PI/PES-fumed silica 5 wt% yielded significant selectivity enhancement of 7.21 and 40.47 for O2/N2, and CO2/CH4, respectively.

  11. Detailed characterization of welding fumes in personal exposure samples

    Science.gov (United States)

    Quémerais, B.; Mino, James; Amin, M. R.; Golshahi, H.; Izadi, H.

    2015-05-01

    The objective of the project was to develop a method allowing for detailed characterization of welding particles including particle number concentration, size distribution, surface chemistry and chemical composition of individual particles, as well as metal concentration of various welding fumes in personal exposure samples using regular sampling equipment. A sample strategy was developed to evaluate the variation of the collection methods on mass concentration. Samples were collected with various samplers and filters at two different locations using our collection system. The first location was using a robotic welding system while the second was manual welding. Collected samples were analysed for mass concentration using gravimetryand metal concentration using ICP/OES. More advanced analysis was performed on selected filters using X-Ray Photoelectron Spectroscopy to determine surface composition of the particles, and X-Ray Diffraction to determine chemical composition of the fumes. Results showed that the robotic system had a lot of variation in space when the collection system was located close to the weld. Collection efficiency was found to be quite variable depending upon the type of filter. As well, metal concentrations in blank filters were dependent upon the type of filter with MCE presenting with the highest blank values. Results obtained with the XRD and XPS systems showed that it was possible to analyse a small of powdered welding fume sample but results on filters were not conclusive.

  12. Soluble transition metals cause the pro-inflammatory effects of welding fumes in vitro

    International Nuclear Information System (INIS)

    McNeilly, Jane D.; Heal, Mathew R.; Beverland, Iain J.; Howe, Alan; Gibson, Mark D.; Hibbs, Leon R.; MacNee, William; Donaldson, Ken

    2004-01-01

    Epidemiological studies have consistently reported a higher incidence of respiratory illnesses such as bronchitis, metal fume fever (MFF), and chronic pneumonitis among welders exposed to high concentrations of metal-enriched welding fumes. Here, we studied the molecular toxicology of three different metal-rich welding fumes: NIMROD 182, NIMROD c276, and COBSTEL 6. Fume toxicity in vitro was determined by exposing human type II alveolar epithelial cell line (A549) to whole welding fume, a soluble extract of fume or the 'washed' particulate. All whole fumes were significantly toxic to A549 cells at doses >63 μg ml -1 (TD 50; 42, 25, and 12 μg ml -1 , respectively). NIMROD c276 and COBSTEL 6 fumes increased levels of IL-8 mRNA and protein at 6 h and protein at 24 h, as did the soluble fraction alone, whereas metal chelation of the soluble fraction using chelex beads attenuated the effect. The soluble fraction of all three fumes caused a rapid depletion in intracellular glutathione following 2-h exposure with a rebound increase by 24 h. In addition, both nickel based fumes, NIMROD 182 and NIMROD c276, induced significant reactive oxygen species (ROS) production in A549 cells after 2 h as determined by DCFH fluorescence. ICP analysis confirmed that transition metal concentrations were similar in the whole and soluble fractions of each fume (dominated by Cr), but significantly less in both the washed particles and chelated fractions. These results support the hypothesis that the enhanced pro-inflammatory responses of welding fume particulates are mediated by soluble transition metal components via an oxidative stress mechanism

  13. Particle packing of cement and silica fume in pastes using an analytical model

    Directory of Open Access Journals (Sweden)

    A. HERMANN

    Full Text Available When added to concrete in appropriate content, silica fume may provide an increase in the mechanical strength of the material due to its high pozzolanic reactivity. In addition to the chemical contribution, physical changes can also be observed in concretes with silica fume due to an improvement in the particle packing of the paste. This is a result of their small size spherical particles, which fill the voids between the larger cement grains. However, it is necessary to properly establish the cement replacement content by silica fume, because at high amounts, which exceed the volume of voids between the cement particles, silica fume can promote the loosening of these particles. Thus, instead of filling the voids and increasing the packing density, the addition of silica fume will increase the volume of voids, decreasing the solid concentration. Consequently, this will impair the properties of the concrete. The objective of this paper is to use a particle packing analytical model, the CPM (Compressible Packing Model, to verify the maximum packing density of cement and silica fume, which could be associated with the silica fume optimum content in pastes. The ideal content of silica fume in pastes, mortars and concretes is usually experimentally determined. However, a theoretical study to contrast experimental data may help understanding the behaviour of silica fume in mixes. Theoretical results show maximum amounts of silica fume in the order of 18 to 20% of the cement weight, which is high considering recommendations on literature of 15%. Nevertheless, the packing model does not consider the effect of silica fume high specific surface on the agglomeration of particles or water demand. Hence, the packing density predicted by this model cannot be used as the single parameter in determining the optimum amount of silica fume in pastes.

  14. Effects of Nano-zinc on Biochemical Parameters in Cadmium-Exposed Rats.

    Science.gov (United States)

    Hejazy, Marzie; Koohi, Mohammad Kazem

    2017-12-01

    Cadmium (Cd) is a toxic environmental and occupational pollutant with reported toxic effects on the kidneys, liver, lungs, bones, and the immunity system. Based on its physicochemical similarity to cadmium, zinc (Zn) shows protective effects against cadmium toxicity and cadmium accumulation in the body. Nano-zinc and nano-zinc oxide (ZnO), recently used in foods and pharmaceutical products, can release a great amount of Zn 2+ in their environment. This research was carried out to investigate the more potent properties of the metal zinc among sub-acute cadmium intoxicated rats. Seventy-five male Wistar rats were caged in 15 groups. Cadmium chloride (CdCl 2 ) was used in drinking water to induce cadmium toxicity. Different sizes (15, 20, and 30 nm) and doses of nano-zinc particles (3, 10, 100 mg/kg body weight [bw]) were administered solely and simultaneously with CdCl 2 (2-5 mg/kg bw) for 28 days. The experimental animals were decapitated, and the biochemical biomarkers (enzymatic and non-enzymatic) were determined in their serum after oral exposure to nano-zinc and cadmium. Statistical analysis was carried out with a one-way ANOVA and t test. P cadmium- and nano-zinc-treated rats compared with the controls. However, albumin, total protein, and HDLc significantly decreased in the cadmium- and nano-zinc-treated rats compared with the controls (P cadmium intoxication.

  15. Manganese in occupational arc welding fumes--aspects on physiochemical properties, with focus on solubility.

    Science.gov (United States)

    Taube, Fabian

    2013-01-01

    Physicochemical properties, such as particle sizes, composition, and solubility of welding fumes are decisive for the bioaccessibility of manganese and thereby for the manganese cytotoxic and neurotoxic effects arising from various welding fumes. Because of the diverse results within the research on welding fume solubility, this article aims to review and discuss recent literature on physicochemical properties of gas metal arc welding, shielded metal arc welding, and flux-cored arc welding fumes, with focus on solubility properties. This article also presents a short introduction to the literature on arc welding techniques, health effects from manganese, and occupational exposure to manganese among welders.

  16. Calcium enhances cadmium tolerance and decreases cadmium ...

    African Journals Online (AJOL)

    Yomi

    2012-04-26

    Apr 26, 2012 ... concentrations alleviated the toxic effect of cadmium on the growth and water status of lettuce plants. The three lettuce varieties ... electroplating, in batteries, in electrical conductors, in the manufacture of alloys ..... Handbook on the Toxicology of Metals, Third edition, Salt Lake City, UT: Acad. Press. Österås ...

  17. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    Science.gov (United States)

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane.

  18. Impact of acute cadmium exposure on the trunk lateral line neuromasts and consequences on the 'C-start' response behaviour of the sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)

    International Nuclear Information System (INIS)

    Faucher, Karine; Fichet, Denis; Miramand, Pierre; Lagardere, Jean Paul

    2006-01-01

    Behavioural responses of sea bass Dicentrarchus labrax were investigated after exposure to cadmium ions in laboratory-controlled conditions. The aim of this study was to discover whether environmental exposure to cadmium ions inactivates fish lateral line system neuromasts, and to determine the behavioural consequences of such a sensory blockage. For this, fish escape behaviour in response to an artificial water jet was recorded using a 25-frames s -1 analog video camera before and after cadmium exposure. Experimental set up was tested with fish whose lateral line system was artificially inactivated by antibiotics (gentamicin and streptomycin). Histological analyses with scanning electron microscopy showed antibiotic treatment destroyed lateral line system neuromasts. In addition, these fish did not respond to stimulations provoked by the water jet after antibiotic treatment. Fish escape behaviour was then recorded before and after cadmium exposure at two different concentrations. When fish were exposed to the first concentration of cadmium tested (0.5 μg l -1 , which represents the maximal cadmium concentration encountered in contaminated estuaries), no alteration in neuromast tissue was observed. In addition, before cadmium exposure, fish responded positively in 98.41 ± 4.95% of lateral line system stimulations (escape behaviour in response to the water jet). After cadmium exposure, no behavioural modification could be detected: the fish responded positively in 95.16 ± 9.79% of stimulations (χ 2 = 2.464, p = 0.116). In contrast, the high cadmium concentration used (5 μg l -1 , which represents 10 times the concentration occurring in highly polluted estuarine areas) involved severe neuromast tissue damage. Just after such cadmium exposure, fish showed only 41.67 ± 35.36% of positive responses to their lateral line system stimulations, while they responded positively in 95.93 ± 9.10% of stimulations under control conditions (χ 2 = 24.562, p 2 = 2.876, p = 0

  19. Simultaneous determination of oxygen and cadmium in cadmium and cadmium compounds

    International Nuclear Information System (INIS)

    Imaeda, K.; Kuriki, T.; Ohsawa, K.; Ishii, Y.

    1977-01-01

    Cadmium and its compounds were analysed for oxygen and cadmium by a modification of the Schutze-Unterzaucher method. Oxygen in some compounds such as cadmium oxide, nitrate and sulphate could not be determined by the usual method. The method of adding carbon was employed for the determination of total oxygen. Total oxygen could be determined by the addition of 5 mg of carbon to a sample boat and heating at 950 0 . The determination was also carried out by addition of naphthalene (2 mg). It was found that the cadmium powder and cadmium flake used contained ca. 1 and 0.15% oxygen, respectively. Oxygen and cadmium in cadmium and its compounds were simultaneously determined by the addition of 2 mg of naphthalene. Cadmium was determined colorimetrically by use of glyoxal-bis-(2-hydroxyanil). Oxygen and cadmium in the samples could be determined simultaneously with an average error of -0.02 and -0.22%, respectively. (author)

  20. Adaptive responses and latent costs of multigeneration cadmium exposure in parasite resistant and susceptible strains of a freshwater snail

    Energy Technology Data Exchange (ETDEWEB)

    Salice, Christopher J.; Anderson, Todd; Roesijadi, Guritno

    2010-11-01

    Population response to anthropogenic activities will be influenced by prior adaptation to environmental conditions. We tested how parasite-resistant and -susceptible strains of a freshwater snail responded to cadmium and elevated temperature challenges after having been exposed to low-level cadmium continuously for multiple generations. Snails exposed to cadmium for three generations were removed for the fourth generation, and challenged in the fifth generation with (1) chronic cadmium exposure over the entire life cycle, (2) acute cadmium exposure of adults, and (3) elevated temperature challenge of adults. The parasite susceptible NMRI strain is more cadmium tolerant than the parasite resistant BS90 strain and remained more tolerant than BS90 throughout this study. Additionally, NMRI exhibited greater adaptive capacity for cadmium than BS90 and became more tolerant of both chronic and acute cadmium challenges, while BS90 became more tolerant of acute cadmium challenge only. Fitness costs, reflected in population growth rate, were not apparent in fifth generation snails maintained in cadmium-free conditions. However, costs were latent and expressed as decreased tolerance to a secondarily imposed temperature stress. Adaptation to prior selection pressures can influence subsequent adaptation to anthropogenic stresses and may have associated costs that reduce fitness in novel environments.

  1. Increased lung function decline in blue-collar workers exposed to welding fumes.

    Science.gov (United States)

    Thaon, Isabelle; Demange, Valérie; Herin, Fabrice; Touranchet, Annie; Paris, Christophe

    2012-07-01

    There is no consensus at the present time about the effect of welding on lung function decline. This study compared lung function decline between blue-collar workers exposed and not exposed to welding fumes in a French longitudinal cohort of 21,238 subjects aged 37 to 52 years at inclusion. Medical data, occupation, sector of activity, and spirometry were recorded twice by occupational physicians in 1990 and 1995. A job-exposure matrix was used to identify 503 male blue-collar workers exposed to welding fumes and 709 control subjects and to define the weekly duration of exposure to welding fumes. Baseline lung function parameters were higher in workers exposed to welding fumes than in control subjects. After a 5-year follow-up, welding-fume exposure was associated with a nonsignificant decline in FVC (P = .06) and FEV(1) (P = .07) after adjustment for age, pack-years, BMI, and baseline value of the parameter. A significant accelerated decline in FEV(1) (P = .046) was also observed in never smokers exposed to welding fumes. An “exposure-response” relationship was observed between FEV(1) decline and weekly duration of exposure to welding fumes in nonsmokers but not in smokers. Blue-collar workers exposed to welding fumes showed accelerated decline in lung function, which, in nonsmokers, was related to weekly duration of exposure.

  2. Effect of paint fumes on histoarchitecture of the testes of adult male ...

    African Journals Online (AJOL)

    Aim: To investigate the effect of paint fumes on the histoarchitecture of the testes. Methodology: In this study, we reported sixteen (16) Wistar rats mainly male of an average weight of 180g. Four groups of four rats each were divided into groups A-D. The treated rats were exposed to paint fumes for 8 hours daily, group A for ...

  3. Indirect Prediction of Welding Fume Diffusion inside a Room Using Computational Fluid Dynamics

    Directory of Open Access Journals (Sweden)

    Sujit Dahal

    2016-05-01

    Full Text Available Welding is an important and widely used process in the manufacturing and maintenance of various works involving metals and alloys. While welding has broad applications, the welding fume generated during the process has impacts on workers’ health, which needs to be addressed. One of the major steps that can be undertaken to take care of this issue is the use of ventilation, which requires knowledge of characteristics and dispersion of the welding fume in the workers’ breathing zone. It is difficult to assess welding fume dispersion from manual measurement due to numerous welding processes and sufficient data requirement. Numerical prediction of welding fume is dubious due to several errors. This paper considers the use of numerically predicted CO2 concentrations to indirectly predict welding fume distribution in workshops. This is based on the assumption that if the particles are sufficiently small size, they follow the diffusion pattern of gases. Experiments are carried out in a room with an opening and a welding fume generation system for measurement of CO2 and fume diffusion. The results show high possibility of predicting welding fume concentration based on Computational Fluid Dynamics (CFD simulated CO2 concentration with a correlation coefficient of 0.74.

  4. Risk of ischemic heart disease following occupational exposure to welding fumes

    DEFF Research Database (Denmark)

    Mocevic, Emina; Kristiansen, Pernille; Bonde, Jens Peter

    2015-01-01

    PURPOSE: Air pollution has been linked to an increased risk of ischemic heart disease (IHD), but less is known about occupational exposure to welding fumes and the risk of IHD. The objective of this paper was to review the epidemiological evidence on causal links between welding fume exposure...

  5. 42 CFR 84.1147 - Silica mist test for dust, fume, and mist respirators; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1147 Silica mist test for dust, fume, and mist... nor more than 25 milligrams of silica mist, weighed as silica dust, per cubic meter of air. (d) Mist...

  6. Cadmium inhibits acid secretion in stimulated frog gastric mucosa

    International Nuclear Information System (INIS)

    Gerbino, Andrea; Debellis, Lucantonio; Caroppo, Rosa; Curci, Silvana; Colella, Matilde

    2010-01-01

    Cadmium, a toxic environmental pollutant, affects the function of different organs such as lungs, liver and kidney. Less is known about its toxic effects on the gastric mucosa. The aim of this study was to investigate the mechanisms by which cadmium impacts on the physiology of gastric mucosa. To this end, intact amphibian mucosae were mounted in Ussing chambers and the rate of acid secretion, short circuit current (I sc ), transepithelial potential (V t ) and resistance (R t ) were recorded in the continuous presence of cadmium. Addition of cadmium (20 μM to 1 mM) on the serosal but not luminal side of the mucosae resulted in inhibition of acid secretion and increase in NPPB-sensitive, chloride-dependent short circuit current. Remarkably, cadmium exerted its effects only on histamine-stimulated tissues. Experiments with TPEN, a cell-permeant chelator for heavy metals, showed that cadmium acts from the intracellular side of the acid secreting cells. Furthermore, cadmium-induced inhibition of acid secretion and increase in I sc cannot be explained by an action on: 1) H 2 histamine receptor, 2) Ca 2+ signalling 3) adenylyl cyclase or 4) carbonic anhydrase. Conversely, cadmium was ineffective in the presence of the H + /K + -ATPase blocker omeprazole suggesting that the two compounds likely act on the same target. Our findings suggest that cadmium affects the functionality of histamine-stimulated gastric mucosa by inhibiting the H + /K + -ATPase from the intracellular side. These data shed new light on the toxic effect of this dangerous environmental pollutant and may result in new avenues for therapeutic intervention in acute and chronic intoxication.

  7. Irritative effects of fumes and aerosols of bitumen on the airways: results of a cross-shift study

    Energy Technology Data Exchange (ETDEWEB)

    Raulf-Heimsoth, Monika; Pesch, Beate; Kappler, Martin; Marczynski, Boleslaw; Rihs, Hans Peter; Merget, Rolf; Bruening, Thomas [Institut der Ruhr-Universitaet Bochum, Berufsgenossenschaftliches Forschungsinstitut fuer Arbeitsmedizin (BGFA), Bochum (Germany); Schott, Klaus [Berufsgenossenschaft der Bauwirtschaft (BG BAU), Munich (Germany); Preuss, Ralf; Angerer, Juergen [Universitaet Erlangen, Institut und Poliklinik fuer Arbeits-, Sozial- und Umweltmedizin (IPASUM), Erlangen (Germany); Hahn, Jens Uwe [Berufsgenossenschaftliches Institut fuer Arbeitsschutz (BGIA), Sankt Augustin (Germany)

    2007-01-15

    Possible health hazards of fumes and aerosols of bitumen are in discussion, and data on their adverse effects on human airways under current exposure conditions are limited. To assess the irritative effects of exposure to fumes and aerosols of bitumen on the airways, a cross-sectional cross-shift study was conducted including external and internal exposure measurements, spirometry and especially non-invasive methods like nasal lavage collection and induction of sputum in order to identify and evaluate more precisely inflammatory process in the upper and lower airways. The cross-shift study comprised 74 mastic asphalt workers who were exposed to fumes and aerosols of bitumen and 49 construction workers without this exposure as reference group. Questionnaire, spirometry, ambient monitoring and urinary analysis were performed. Humoral and cellular parameters were measured in nasal lavage fluid (NALF) and induced sputum. For data analysis, a mixed linear model was performed on the different outcomes with exposure group, time of measurement (pre-, post-shift), current smoking, German nationality and age as fixed factors and subjects as random factor. Based on personal exposure measurements during shift, mastic asphalt workers were classified into a low ({<=}10 mg/m{sup 3}; n = 46) and a high (>10 mg/m{sup 3}; n = 28) exposure group. High exposure was accompanied by significant higher urinary post-shift concentrations of 1-hydroxypyrene and the sum of hydroxyphenanthrenes. Acute respiratory symptoms were reported more frequently in the high exposure group after shift. Significant cross-shift declines in lung function parameters (forced expiratory volume in 1 s [FEV{sub 1} (% predicted)] and forced vital capacity [FVC (% predicted)]) were measured in mastic asphalt workers. Pre-shift FEV{sub 1} (% predicted) and FVC (% predicted) were higher in the low exposure group. In pre- and post-shift NALF samples, interleukin (IL)-1{beta}-, IL-8- and total protein concentrations

  8. Cadmium Transporters in the Kidney and Cadmium-Induced Nephrotoxicity

    Science.gov (United States)

    Yang, Hong; Shu, Yan

    2015-01-01

    Among the organs in which the environmental pollutant cadmium causes toxicity, the kidney has gained the most attention in recent years. Numerous studies have sought to unravel the exact pathways by which cadmium enters the renal epithelial cells and the mechanisms by which it causes toxicity in the kidney. The purpose of this review is to present the progress made on the mechanisms of cadmium transport in the kidney and the role of transporter proteins in cadmium-induced nephrotoxicity. PMID:25584611

  9. 42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.

    Science.gov (United States)

    2010-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1143 Dust, fume, and mist air-purifying filter tests... 42 Public Health 1 2010-10-01 2010-10-01 false Dust, fume, and mist air-purifying filter tests...

  10. Designing, Constructing and Installing a Local Exhaust Ventilation System to Minimize Welders\\' Exposure to Welding Fumes

    Directory of Open Access Journals (Sweden)

    Sajad Zare

    2017-10-01

    Full Text Available Background & Aims of the Study: Welder’s exposure to welding fumes can cause occupational diseases. The current study sought to examine exposure to welding fumes among welders who work in the repair shop of Sarcheshmeh Copper Complex and design a local exhaust ventilation system to control exposure to welding fumes. Materials & Methods: This applied analytical study was conducted in the summer of 2016 among welders working in the repair shop of Sarcheshmeh Copper Complex. The study comprised three phases; in the first one, welders’ exposure to welding fumes was assessed at the beginning of the study. After that, a local exhaust ventilation system was designed and installed in the aforementioned repair shop. In the final stage, welders’ exposure to welding fumes was assessed again after installation of the ventilation system. The procedure recommended by NIOSH (method number 7300 was used for individual sampling of welders. Results: Based on the obtained findings, before installing the ventilation system, welding technicians were exposed to 0.3 mg/m3 of copper fumes and 0.04 mg/m3 of chromium fumes. Journeyman welders were also exposed to 2.16 mg/m3 of manganese fumes, while stellar welders were exposed to 6.9 mg/m3 of iron fumes. In the light of these measurements, a local exhaust ventilation system was designed and installed. Subsequently, measurement of exposure to welding fumes showed a significant reduction. That is, welding technicians were exposed to 0.17 mg/m3 and 0.015 mg/m3 of copper and chromium fumes respectively. Additionally, journeyman welders were exposed to 0.86 mg/m3 of manganese fumes, whereas stellar welders were exposed to 4.3 mg/m3 of iron fumes. Conclusions: A comparison of standard limits of exposure to welding fumes and the results obtained from measurements in sampling stations before and after the installation of the local exhaust ventilation system reveals that this controlling measure was very effective in the

  11. Chronic cadmium exposure stimulates SDF-1 expression in an ERα dependent manner.

    Directory of Open Access Journals (Sweden)

    Esmeralda Ponce

    Full Text Available Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell line chronically exposed to 10(-7 M CdCl2 serves as our model system. Data suggest that prolonged cadmium exposures result in the development of more aggressive cancer phenotypes - increased cell growth, migration and invasion. The results from this study show for the first time that chronic cadmium exposure stimulates the expression of SDF-1 by altering the molecular interactions between ERα, c-jun and c-fos. This study provides a mechanistic link between chronic cadmium exposure and ERα and demonstrates that prolonged, low-level cadmium exposure contributes to breast cancer progression.

  12. Investigation of durability of silica fume concretes in coastal structures within tidal zone

    International Nuclear Information System (INIS)

    Ganjian, E.; Sadeghi Pouya, H.

    2003-01-01

    In recent decade use of silica fume has been become greater in coastal concrete structures in the persona gulf, to increase durability of those establishments. In this research the durability of cement passers and concrete cubes with use of 7 and 10 percent of silica fume as a cement replacement have been investigated in three curing conditions (fresh water, coast of sea and simulation bonds) by measuring compressive strengths and capillary absorption. Silica fume specimens under wetting and drying condition showed more strength loss after 180 days compare to samples without silica fume or cured in the fresh water. In addition the greater silica fume amount in specimens cured within tidal zone and under wetting and drying simulation, the more water absorption by capillary. According to the results, good correspondence between simulated condition and real site exposure was obtained

  13. Synthetic Reference Materials Based on Polymer Films for the Control of Welding Fumes Composition

    Science.gov (United States)

    Kuznetsova, O. V.; Kuznetsova, A. N.; Begunova, L. A.

    2017-04-01

    Analysis of the current hygienic situation in the welding production showed that the intensification of welding processes involves the deterioration of air quality, which negatively affects the welders health. Welders are exposed to a variety of metal fumes, including manganese that may elevate the risk for neurological diseases. The control of metals concentration in the air of the working area is difficult due to the lack of reference materials. The creation of reference materials of welding fumes composition is a challenge due to chemical characteristics of their physical properties. Synthetic samples in a form of the polymer film containing powder particles of welding fumes were create. Studies on the selection of the polymer were done. Experiments proved that the qualitative materials of synthetic welding fumes are obtained by using polyvinyl alcohol. The metals concentration in the samples was determined by X-ray fluorescence analysis. The obtained data demonstrates indirectly the uniform distribution of welding fumes powder particles on the polymer film.

  14. Flux of Cadmium through Euphausiids

    International Nuclear Information System (INIS)

    Benayoun, G.; Fowler, S.W.; Oregioni, B.

    1976-01-01

    Flux of the heavy metal cadmium through the euphausiid Meganyctiphanes norvegica was examined. Radiotracer experiments showed that cadmium can be accumulated either directly from water or through the food chain. When comparing equilibrium cadmium concentration factors based on stable element measurements with those obtained from radiotracer experiments, it is evident that exchange between cadmium in the water and that in euphausiid tissue is a relatively slow process, indicating that, in the long term, ingestion of cadmium will probably be the more important route for the accumulation of this metal. Approximately 10% of cadmium ingested by euphausiids was incorporated into internal tissues when the food source was radioactive Artemia. After 1 month cadmium, accumulated directly from water, was found to be most concentrated in the viscera with lesser amounts in eyes, exoskeleton and muscle, respectively. Use of a simple model, based on the assumption that cadmium taken in by the organism must equal cadmium released plus that accumulated in tissue, allowed assessment of the relative importance of various metabolic parameters in controlling the cadmium flux through euphausiids. Fecal pellets, due to their relatively high rate of production and high cadmium content, accounted for 84% of the total cadmium flux through M. norvegica. Comparisons of stable cadmium concentrations in natural euphausiid food and the organism's resultant fecal pellets indicate that the cadmium concentration in ingested material was increased nearly 5-fold during its passage through the euphausiid. From comparisons of all routes by which cadmium can be released from M. norvegica to the water column, it is concluded that fecal pellet deposition represents the principal mechanism effecting the downward vertical transport of cadmium by this species. (author)

  15. Nanocomposite of SBR/Hydroxy-terminated Polybutadiene Grafted- Fumed Silica

    Directory of Open Access Journals (Sweden)

    Mohamad Reza Pourhossaini

    2012-12-01

    Full Text Available Modified fumed silica, grafted by hydroxyl-terminated polybutadiene(HTPB via toluene diisocyanate (TDI bridging, was incorporated instyrene butadiene rubber (SBR as reinforcing filler. The main objectiveof this work was to study the effect of the modification method on final properties of the rubber compounds. As compared to unmodified nanosilica, scanning electron microscopy (SEM represented nano dispersion of modified fumed silica particles in SBR compound. The results of mechanical uniaxial tensile test revealed the significant reinforcement property of HTPB-surface grafted nanosilica. This strong effect is attributed not only to nanodispersion of silica particles but also due to participation of HTPB double ligands in sulfur curing system of SBR and chemical linkage between rubber matrix and silica particles. The study of dynamic mechanical properties under temperature scan (linear viscoelasticity displayed strong interaction between the rubber matrix and modified silica particles and it again reaffirmed the efficient reinforcement effect of this filler. Also, dynamic mechanical properties under strain scan (non-linear viscoelasticity exhibited filler network formation at low filler content for this modified nanosilica. Surface modification of nanosilica by HTPB grafting intensified the mechanical reinforcement of the filler; meanwhile, it reduced the intensity of non-linear behavior by weakening the effect of filler network break down (Payne effect relative to that of unmodified silica. Therefore, this method of silica surface modification could be a novel method in improvement of the final properties of filled SBR by nanosilica.

  16. Uptake and loss of absorbed dissolved cadmium to Clarias ...

    African Journals Online (AJOL)

    GRACE

    2006-06-16

    Jun 16, 2006 ... Res NATO Sci. Comm. Conf. 7: 187-195 London. Eisler R, Gardner GR (1973). Acute toxicology to an estuarine teleost of mistures of cadmuim, copper, and zinc salts. J. Fish. Biol. 5: 131 – 142. Eisler R (1974). Radio cadmium exchange with seawater by. Fundulus heteroclitus (L) (Pisces: Cyprinodontidae) ...

  17. Effects of Cadmium Compounds (Cadmium Para Hydroxybenzoate and Cadmium Chloride) on the Liver of Mature Mice

    OpenAIRE

    ERSAN, Yusuf; ARI, İsmail; KOÇ, Evren

    2014-01-01

    In this study, 4 experimental groups and 1 control group containing adult mice (Mus musculus var. albinos) were used to examine the effects of 2 different cadmium compounds, namely cadmium para hydroxybenzoate, which was newly synthesized, and cadmium chloride on the liver of mice. In various test concentrations, both cadmium compounds were intraperitoneally injected into adult mice every day for 15 days. With standard histological techniques samples were obtained from the livers of the mice...

  18. Effects of Calcined clay minerals and Silica fume on the compressive strength of concrete

    Directory of Open Access Journals (Sweden)

    Abolfazl Soltani

    2017-05-01

    Full Text Available Pozzolanic materials are well known as potential replacements for cement manufacturing in order to increase compressive strength and improve durability of concrete in different environments and leading to save energy particularly reducing global warming effect. The present study reveals the effect of calcined clay minerals as natural pozzolanic material, separately and in combination with and without silica fume. To achieve this aim, 15 mixed designs with a constant water to cementitious ratio of  0.38 is made. In six mixed designs only metakaolin, zeolite or silica fume  and in eight other designs metakaolin and silica fume or zeolite and silica fume have been combined. Mixes containing metakaolin or zeolite with ratio of 10 or 20 percent and silica fume with 7 or 10 percent show significant increasing in compressive strength and improving durability, being valuable replacement for cement (in percentages. In particular, the best practice is attributed to the age of 28 days for compressive strength the replacement of the composition is 10% zeolite with 7% of silica fume and for electrical resistance the replacement of the composition is 10% zeolite with 7% of silica fume.

  19. Oxidation process of cadmium sulfide

    International Nuclear Information System (INIS)

    Hashimoto, Koshiro; Toda, Yoshitomo; Sato, Takayori

    1977-01-01

    Complicated thermogravimetric curve was observed on oxidation process of cadmium sulfide precipitate in air. Phases of various oxidation stage were identified by X-ray diffraction method. Cadmium sulfide was first oxidized to cadmium oxide at 400 0 C, while the successive reaction with sulfur dioxide and oxygen gases gave rise to cadmium sulfate. The phases such as 2 CdS. CdSO 4 , Cd 3 SO 6 and β-CdSO 4 appeared during the oxidation process up to 1100 0 C, at which all the particles were converted into cadmium oxide at 1100 0 C. Cadmium sulfide kept in nitrogen gas above 700 0 C was directly converted into cadmium oxide when oxygen gas was introduced into the furnace. (auth.)

  20. Modifying welding process parameters can reduce the neurotoxic potential of manganese-containing welding fumes.

    Science.gov (United States)

    Sriram, Krishnan; Lin, Gary X; Jefferson, Amy M; Stone, Samuel; Afshari, Aliakbar; Keane, Michael J; McKinney, Walter; Jackson, Mark; Chen, Bean T; Schwegler-Berry, Diane; Cumpston, Amy; Cumpston, Jared L; Roberts, Jenny R; Frazer, David G; Antonini, James M

    2015-02-03

    Welding fumes (WF) are a complex mixture of toxic metals and gases, inhalation of which can lead to adverse health effects among welders. The presence of manganese (Mn) in welding electrodes is cause for concern about the potential development of Parkinson's disease (PD)-like neurological disorder. Consequently, from an occupational safety perspective, there is a critical need to prevent adverse exposures to WF. As the fume generation rate and physicochemical characteristics of welding aerosols are influenced by welding process parameters like voltage, current or shielding gas, we sought to determine if changing such parameters can alter the fume profile and consequently its neurotoxic potential. Specifically, we evaluated the influence of voltage on fume composition and neurotoxic outcome. Rats were exposed by whole-body inhalation (40 mg/m(3); 3h/day × 5 d/week × 2 weeks) to fumes generated by gas-metal arc welding using stainless steel electrodes (GMA-SS) at standard/regular voltage (25 V; RVSS) or high voltage (30 V; HVSS). Fumes generated under these conditions exhibited similar particulate morphology, appearing as chain-like aggregates; however, HVSS fumes comprised of a larger fraction of ultrafine particulates that are generally considered to be more toxic than their fine counterparts. Paradoxically, exposure to HVSS fumes did not elicit dopaminergic neurotoxicity, as monitored by the expression of dopaminergic and PD-related markers. We show that the lack of neurotoxicity is due to reduced solubility of Mn in HVSS fumes. Our findings show promise for process control procedures in developing prevention strategies for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce adverse neurological risks. Published by Elsevier Ireland Ltd.

  1. Modifying welding process parameters can reduce the neurotoxic potential of manganese-containing welding fumes

    International Nuclear Information System (INIS)

    Sriram, Krishnan; Lin, Gary X.; Jefferson, Amy M.; Stone, Samuel; Afshari, Aliakbar; Keane, Michael J.; McKinney, Walter; Jackson, Mark; Chen, Bean T.; Schwegler-Berry, Diane; Cumpston, Amy; Cumpston, Jared L.; Roberts, Jenny R.; Frazer, David G.; Antonini, James M.

    2015-01-01

    Welding fumes (WF) are a complex mixture of toxic metals and gases, inhalation of which can lead to adverse health effects among welders. The presence of manganese (Mn) in welding electrodes is cause for concern about the potential development of Parkinson’s disease (PD)-like neurological disorder. Consequently, from an occupational safety perspective, there is a critical need to prevent adverse exposures to WF. As the fume generation rate and physicochemical characteristics of welding aerosols are influenced by welding process parameters like voltage, current or shielding gas, we sought to determine if changing such parameters can alter the fume profile and consequently its neurotoxic potential. Specifically, we evaluated the influence of voltage on fume composition and neurotoxic outcome. Rats were exposed by whole-body inhalation (40 mg/m 3 ; 3 h/day × 5 d/week × 2 weeks) to fumes generated by gas–metal arc welding using stainless steel electrodes (GMA-SS) at standard/regular voltage (25 V; RVSS) or high voltage (30 V; HVSS). Fumes generated under these conditions exhibited similar particulate morphology, appearing as chain-like aggregates; however, HVSS fumes comprised of a larger fraction of ultrafine particulates that are generally considered to be more toxic than their fine counterparts. Paradoxically, exposure to HVSS fumes did not elicit dopaminergic neurotoxicity, as monitored by the expression of dopaminergic and PD-related markers. We show that the lack of neurotoxicity is due to reduced solubility of Mn in HVSS fumes. Our findings show promise for process control procedures in developing prevention strategies for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce adverse neurological risks

  2. Effect of Silica Fume on two-stage Concrete Strength

    Science.gov (United States)

    Abdelgader, H. S.; El-Baden, A. S.

    2015-11-01

    Two-stage concrete (TSC) is an innovative concrete that does not require vibration for placing and compaction. TSC is a simple concept; it is made using the same basic constituents as traditional concrete: cement, coarse aggregate, sand and water as well as mineral and chemical admixtures. As its name suggests, it is produced through a two-stage process. Firstly washed coarse aggregate is placed into the formwork in-situ. Later a specifically designed self compacting grout is introduced into the form from the lowest point under gravity pressure to fill the voids, cementing the aggregate into a monolith. The hardened concrete is dense, homogeneous and has in general improved engineering properties and durability. This paper presents the results from a research work attempt to study the effect of silica fume (SF) and superplasticizers admixtures (SP) on compressive and tensile strength of TSC using various combinations of water to cement ratio (w/c) and cement to sand ratio (c/s). Thirty six concrete mixes with different grout constituents were tested. From each mix twenty four standard cylinder samples of size (150mm×300mm) of concrete containing crushed aggregate were produced. The tested samples were made from combinations of w/c equal to: 0.45, 0.55 and 0.85, and three c/s of values: 0.5, 1 and 1.5. Silica fume was added at a dosage of 6% of weight of cement, while superplasticizer was added at a dosage of 2% of cement weight. Results indicated that both tensile and compressive strength of TSC can be statistically derived as a function of w/c and c/s with good correlation coefficients. The basic principle of traditional concrete, which says that an increase in water/cement ratio will lead to a reduction in compressive strength, was shown to hold true for TSC specimens tested. Using a combination of both silica fume and superplasticisers caused a significant increase in strength relative to control mixes.

  3. Characterization of Particulate Fume and Oxides Emission from Stainless Steel Plasma Cutting.

    Science.gov (United States)

    Wang, Jun; Hoang, Tien; Floyd, Evan L; Regens, James L

    2017-04-01

    Plasma cutting is a metal fabrication process that employs an electrically conductive plasma arc to cut metals. The metal fume emitted from stainless steel plasma cutting may consist of hexavalent chromium (Cr6+), which is a carcinogen, and other toxicants. Overexposure to plasma cutting fume may cause pulmonary toxicity and other health effects. This study was to evaluate the effects of operation parameters (arc current and arc time) on the fume formation rates, Cr6+ and other oxides concentrations, particle size distributions (PSD), and particle morphology. A fume chamber and high-volume pump were used to collect fume produced from cutting ER308L stainless steel plates with arc currents varying between 20 and 50 A. The amount of fume collected on glass fiber filters was gravimetrically determined and normalized to arc time. Cr6+ and other oxides in the fume were analyzed using ion chromatography. PSD of the fume was examined using a scanning mobility particle sizer and an aerodynamic particle sizer for fine and coarse fractions, respectively. The particle morphology was imaged through a transmission electron microscope (TEM). Total fume generation rate increased with arc current and ranged from 16.5 mg min-1 at 20 A to 119.0 mg min-1 at 50 A. Cr6+ emissions (219.8-480.0 µg min-1) from the plasma cutting were higher than welding fume in a previous study. Nitrogen oxides level can be an indicator of oxidation level and Cr6+ formation (R = 0.93). Both PSD measurement and TEM images confirmed a multimodal size distribution. A high concentration of a fine fraction of particles with geometric mean sizes from 96 to 235 nm was observed. Higher arc current yielded more particles, while lower arc current was not able to penetrate the metal plates. Hence, the worker should optimize the arc current to balance cut performance and fume emission. The findings indicated that arc current was the dominant factor in fume emission from plasma cutting. Appropriate ventilation and

  4. Cadmium plating replacements

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  5. zinc, chromium, cadmium

    African Journals Online (AJOL)

    2016-06-30

    Jun 30, 2016 ... Cadmium also causes destruction of the immune system, thus, predisposes the consumer to infectious diseases like tuberculosis (Khan et al., 2008). ... years, sputum specimens positive for acid-fast bacilli by microscopy and clinical and radiographic abnormalities consistent with pulmonary tuberculosis.

  6. Speciation of Dissolved Cadmium

    DEFF Research Database (Denmark)

    Holm, Peter Engelund; Andersen, Sjur; Christensen, Thomas Højlund

    1995-01-01

    Equilibrium dialysis and ion exchange methods, as well as computer calculations (GEOCHEM), were applied for speciation of dissolved cadmium (Cd) in test solutions and leachate samples. The leachate samples originated from soil, compost, landfill waste and industrial waste. The ion exchange (IE...

  7. Acute toxicity of copper and cadmium for piauçu, Leporinus macrocephalus, and curimatã, Prochilodus vimboides - DOI: 10.4025/actascibiolsci.v31i3.5069

    OpenAIRE

    Gomes, Levy Carvalho; UVV; Chippari-Gomes, Adriana Regina; UVV; Oss, Rodrigo Nunes; Fernandes, Luis Fernando Loureiro; UFES; Magris, Rafael de Almeida; UFES

    2009-01-01

    Ninety-six-hour static bioassays were conducted in the laboratory to determine lethal concentrations (96-h LC50) of copper and cadmium for curimatã (Prochilodus vimboides) and piauçu (Leporinus macrocephalus). The 96-h LC50 of copper were 0.047 and 0.090 mg L-1, and of cadmium 3.16 and 7.42 mg L-1 for curimatã and piauçu, respectively. Curimatã is a preferred indigenous species for toxicological studies in the Doce River basin due to its availability in the hatcheries of the region and high s...

  8. Minimum acceptable face velocities of laboratory fume hoods and guidelines for their classification

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, N.E.; Porter, W.E.; Alcorn, S.P.; Everett, W.S.; Hunt, J.B.; Morehead, J.F.; Higdon, H.F.

    1978-06-01

    Data developed to support the requirement of a 100 LFM minimum face velocity requirement for laboratory fume hoods are summarized. Also included is a description of the Y-12 test hood as well as guidelines for a hood classification scheme.

  9. Morphological Evolution of Low-Grade Silica Fume at Elevated Temperature

    Science.gov (United States)

    Chen, Junhong; Li, Tong; Li, Xiaoping; Chou, Kuo-Chih; Hou, Xinmei

    2017-07-01

    To solve the environmental pollution problem caused by low-grade silica fume (SiO2, air was investigated using TG-DTA, SEM and TEM techniques. The structural development of silica fume was further analyzed using FT-IR and Raman spectrum. The results show that silica fume contains many defects of broken bands such as Si-O or ≡Si at room temperature. When exposed to the moister or water, the broken bonds tend to react with water and result in the formation of Si-OH and adjacent hydroxyl groups of Si-OH•OH-Si. At elevated temperature up to 900 °C, the structure of silica fume becomes compact due to the reconstruction of the broken bonds caused by the dehydration reaction.

  10. The mechanism of cesium immobilization in densified silica-fume blended cement pastes

    International Nuclear Information System (INIS)

    Bar-Nes, G.; Katz, A.; Peled, Y.; Zeiri, Y.

    2008-01-01

    The role of silica-fume agglomerates, found in densified silica-fume (DSF) pastes, in the immobilization mechanism of Cs ions was studied. Samples of cementitious pastes containing two different forms of silica fume - DSF and raw silica fume (RSF) - were prepared. Leaching experiments showed that both additives reduced the leachability of the metal ion, but the effect of the DSF paste was much stronger. Scanning Electron Microscopy, together with Differential Thermal Analysis, proved that no agglomerated particles were present in the RSF pastes and that the extent of pozzolanic reactivity was higher. We therefore believe that unreacted silica within the DSF agglomerates adsorbs Cs ions and consequently increases their immobilization. Furthermore, this work suggests that during the pozzolanic reaction, a hydrated rim develops around the agglomerate that acts as an additional diffusion barrier for the Cs ions, resulting in an increased efficiency of Cs immobilization

  11. Improvement of RVNRL film properties by adding fumed silica and hydroxy apatite

    Directory of Open Access Journals (Sweden)

    Adul Thiangchanya

    2003-01-01

    Full Text Available The effect of adding fumed silica and hydroxy apatite to Radiation Vulcanized Natural Rubber Latex (RVNRL for improving tear strength, aging properties, degradability and water-soluble protein content of rubber films has been investigated. The addition of fumed silica and hydroxy apatite in RVNRL improves tear strength and aging properties of rubber films, whereas tensile strength and degradability of rubber films were unchanged during storage at room temperature. The water-soluble protein content in rubber films was reduced by immobilization of the fumed silica and hydroxy apatite and enhanced by addition of ZnO. This may reduce allergy problems of natural rubber latex products caused by water-soluble protein. The MST of the RVNRL with fumed silica and hydroxy apatite indicated that the latex must be used within two months after mixing because of its stability.

  12. Minimum acceptable face velocities of laboratory fume hoods and guidelines for their classification

    International Nuclear Information System (INIS)

    Bolton, N.E.; Porter, W.E.; Alcorn, S.P.; Everett, W.S.; Hunt, J.B.; Morehead, J.F.; Higdon, H.F.

    1978-06-01

    Data developed to support the requirement of a 100 LFM minimum face velocity requirement for laboratory fume hoods are summarized. Also included is a description of the Y-12 test hood as well as guidelines for a hood classification scheme

  13. A comparison between atmospheric/humidity and vacuum cyanoacrylate fuming of latent fingermarks.

    Science.gov (United States)

    Farrugia, Kevin J; Fraser, Joanna; Friel, Lauren; Adams, Duncan; Attard-Montalto, Nicola; Deacon, Paul

    2015-12-01

    A number of pseudo-operational trials were set up to compare the atmospheric/humidity and vacuum cyanoacrylate fuming processes on plastic carrier bags. The fuming processes were compared using two-step cyanoacrylate fuming with basic yellow 40 (BY40) staining and a one-step fluorescent cyanoacrylate fuming, Lumicyano 4%. Preliminary work using planted fingermarks and split depletions were performed to identify the optimum vacuum fuming conditions. The first pseudo-operational trial compared the different fuming conditions (atmospheric/humidity vs. vacuum) for the two-step process where an additional 50% more marks were detected with the atmospheric/humidity process. None of the marks by the vacuum process could be observed visually; however, a significant number of marks were detected by fluorescence after BY40 staining. The second trial repeated the same work in trial 1 using the one-step cyanoacrylate process, Lumicyano at a concentration of 4%. Trial 2 provided comparable results to trial 1 and all the items were then re-treated with Lumicyano 4% at atmospheric/humidity conditions before dyeing with BY40 to provide the sequences of process A (Lumicyano 4% atmospheric-Lumicyano 4% atmospheric-BY40) and process B (Lumicyano 4% vacuum-Lumicyano 4% atmospheric-BY40). The number of marks (visual and fluorescent) was counted after each treatment with a substantial increase in the number of detected marks in the second and third treatments of the process. The increased detection rate after the double Lumicyano process was unexpected and may have important implications. Trial 3 was performed to investigate whether the amount of cyanoacrylate and/or fuming time had an impact on the results observed in trial 2 whereas trial 4 assessed if the double process using conventional cyanoacrylate, rather than Lumicyano 4%, provided an increased detection rate. Trials 3 and 4 confirmed that doubling the amount of Lumicyano 4% cyanoacrylate and fuming time produced a lower

  14. Comparative microscopic study of human and rat lungs after overexposure to welding fume.

    Science.gov (United States)

    Antonini, James M; Roberts, Jenny R; Schwegler-Berry, Diane; Mercer, Robert R

    2013-11-01

    Welding is a common industrial process used to join metals and generates complex aerosols of potentially hazardous metal fumes and gases. Most long-time welders experience some type of respiratory disorder during their time of employment. The use of animal models and the ability to control the welding fume exposure in toxicology studies have been helpful in developing a better understanding of how welding fumes affect health. There are no studies that have performed a side-by-side comparison of the pulmonary responses from an animal toxicology welding fume study with the lung responses associated with chronic exposure to welding fume by a career welder. In this study, post-mortem lung tissue was donated from a long-time welder with a well-characterized work background and a history of extensive welding fume exposure. To simulate a long-term welding exposure in an animal model, Sprague-Dawley rats were treated once a week for 28 weeks by intratracheal instillation with 2mg of a stainless steel, hard-surfacing welding fume. Lung tissues from the welder and the welding fume-treated rats were examined by light and electron microscopy. Pathological analysis of lung tissue collected from the welder demonstrated inflammatory cell influx and significant pulmonary injury. The poor and deteriorating lung condition observed in the welder examined in this study was likely due to exposure to very high levels of potentially toxic metal fumes and gases for a significant number of years due to work in confined spaces. The lung toxicity profile for the rats treated with welding fume was similar. For tissue samples from both the welder and treated rats, welding particle accumulations deposited and persisted in lung structures and were easily visualized using light microscopic techniques. Agglomerates of deposited welding particles mostly were observed within lung cells, particularly alveolar macrophages. Analysis of individual particles within the agglomerates showed that these

  15. Effect of silica fume on reaction products of uranium (VI) with portland cement

    International Nuclear Information System (INIS)

    Tan Hongbin; Shaanxi Univ. of Technology, Hanzhong; Li Yuxiang

    2005-01-01

    Simulation of radioactive waste of U(VI) by uranyl nitrate and the effects of different additive quantities (12%, 20%, 30%, 35%, 40%) of silica fume on the products of U(VI) with Portland cement were studied at a hydrothermal condition of 180 degree C for a duration of one week. The X-ray powder diffraction examination results showed that the calcium uranate would be transformed into uranophane when the cement contained 30% silica fume. (authors)

  16. Indirect Prediction of Welding Fume Diffusion inside a Room Using Computational Fluid Dynamics

    OpenAIRE

    Sujit Dahal; Taehyeung Kim; Kwangseog Ahn

    2016-01-01

    Welding is an important and widely used process in the manufacturing and maintenance of various works involving metals and alloys. While welding has broad applications, the welding fume generated during the process has impacts on workers’ health, which needs to be addressed. One of the major steps that can be undertaken to take care of this issue is the use of ventilation, which requires knowledge of characteristics and dispersion of the welding fume in the workers’ breathing zone. It is diff...

  17. SIMRAC welding occupational health and safety resources CD and booklet on welding fume

    CSIR Research Space (South Africa)

    Stanton, WD

    2003-07-01

    Full Text Available and Gases 7. Training 8. Legislation 9. Occupational Exposure Limits (OELs) 10. Air Monitoring 11. Medical Monitoring Appendix 1 - Assessment and management of risks from particulate fume and gases Appendix 2 - Hazards of welding in confined spaces... Appendix 3 - Solvents and degreasers Appendix 4 - Material Safety Data Sheets (MSDS) and Labelling Appendix 5 - Materials causing risks from fumes and gases during soldering Appendix 6 - Relevant OELs Appendix 7 - International and National Standards...

  18. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; McGeer, James C.; Vijayan, Mathilakath M.

    2014-01-01

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  19. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); McGeer, James C. [Department of Biology, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-01-15

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  20. Non-occupational exposure to paint fumes during pregnancy and fetal growth in a general population.

    Science.gov (United States)

    Sørensen, Mette; Andersen, Anne-Marie N; Raaschou-Nielsen, Ole

    2010-05-01

    Occupational exposure to organic solvents during pregnancy has been associated with reduced fetal growth. Though organic solvents in the form of paint fumes are also found in the home environment, no studies have investigated the effect of such exposure in a general population. We studied associations between residential exposure to paint fumes during pregnancy and fetal growth within the Danish National Birth Cohort which consecutively recruited pregnant women from 1996 to 2002 from all over Denmark. Around the 30th pregnancy week, 19,000 mothers were interviewed about use of paint in their residence during pregnancy. The mothers were also asked about smoking habits and alcohol consumption during pregnancy, pre-pregnancy weight, height, parity and occupation. Information on birth weight and gestational age was obtained from national registers. We found that 45% of the mothers had been exposed to paint fumes in their residence during pregnancy. We found a statistically significant inverse relationship between exposure to paint fumes and the risk of being small for gestational age. There were no statistically significant associations between exposure to paint fumes and birth weight and risk of preterm birth after adjustment for potential confounders. Our results suggest that there are no causal relationship between non-occupational exposure to paint fumes in the residence during pregnancy and fetal growth. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Alternatives for Benzene in the Extraction of Bitumen Fume from Exposure Sample Media.

    Science.gov (United States)

    Sutter, Benjamin; Ravera, Christel; Hussard, Caroline; Langlois, Eddy

    2016-01-01

    Benzene is frequently used to extract collected bitumen fumes from personal sampler substrates. However, this solvent is particularly dangerous because of its carcinogenicity (group 1 of the International Agency for Research on Cancer classification). Therefore, to prevent the exposure of laboratory technicians to benzene during the fume extraction step from samplers, a compromise had to be found to identify a less toxic solvent with the same extraction capacity. To compare the extraction capacities of selected solvents, bitumen fumes were generated in the laboratory from three different batches of road surfacing bitumen collected on dedicated bitumen fume samplers. The samplers were then extracted by benzene and the solvents tested. Of 11 selected solvents less toxic than benzene and used in studies on bitumen and bitumen fume analyses, n-hexane and n-heptane were identified as alternatives to benzene. In particular, the results demonstrated that n-heptane was the best candidate solvent for benzene replacement, due to its extraction efficiency comparable to benzene for the three bitumen fumes tested and its low toxicity, which is highly compatible with benzene replacement. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  2. Cadmium in Sweden - environmental risks

    Energy Technology Data Exchange (ETDEWEB)

    Parkman, H.; Iverfeldt, Aa. [Swedish Environmental Research Inst. (Sweden); Borg, H.; Lithner, G. [Stockholm Univ. (Sweden). Inst. for Applied Environmental Research

    1998-03-01

    This report aims at assessing possible effects of cadmium in the Swedish environment. Swedish soils and soft freshwater systems are, due to a generally poor buffering capacity, severely affected by acidification. In addition, the low salinity in the Baltic Sea imply a naturally poor organism structure, with some important organisms living close to their limit of physiological tolerance. Cadmium in soils is mobilized at low pH, and the availability and toxicity of cadmium in marine systems are enhanced at low salinity. The Swedish environment is therefore extra vulnerable to cadmium pollution. The average concentrations of cadmium in the forest mor layers, agricultural soils, and fresh-waters in Sweden are enhanced compared to `back-ground concentrations`, with a general increasing trend from the north to the south-west, indicating strong impact of atmospheric deposition of cadmium originating from the central parts of Europe. In Swedish sea water, total cadmium concentrations, and the fraction of bio-available `free` cadmium, generally increases with decreasing salinity. Decreased emissions of cadmium to the environment have led to decreasing atmospheric deposition during the last decade. The net accumulation of cadmium in the forest mor layer has stopped, and even started to decrease. In northern Sweden, this is due to the decreased deposition, but in southern Sweden the main reason is increased leakage of cadmium from the topsoil as a consequence of acidification. As a result, cadmium in the Swedish environments is undergoing an extended redistribution between different soil compartments, and from the soils to the aquatic systems. 90 refs, 23 figs, 2 tabs. With 3 page summary in Swedish

  3. Cadmium: The deformed metal

    International Nuclear Information System (INIS)

    Stubbs, R.L.

    1979-01-01

    The paper, which is a somewhat abridged version of the introductory paper of the 2nd International Cadmium Conference in Cannes on February 6 to 8, 1979, outlines the present trends in production, reserves, consumption, world trade, prices, and cost. Due to the lack of statistics on the USSR and other socialist countries, the review is limited to the non-socialist world. (orig./IHOE) [de

  4. Interaction of chelating agents with cadmium in mice and rats

    International Nuclear Information System (INIS)

    Eybl, V.; Sykora, J.; Koutensky, J.; Caisova, D.; Schwartz, A.; Mertl, F.

    1984-01-01

    The influence of several chelating agents (CaDTPA, ZnDTPA, CaEDTA, ZnEDTA, DMSA, D-penicillamine and DMPS, DMP and DDC) on the acute toxicity of CdCl 2 and on the whole body retention and tissue distribution of cadmium after the IV application of /sup 115mCdCl 2 was compared in mice. The chelating agents were applied immediately after the application of cadmium. CaDTPA, ZnDTPA and DMSA appeared to be the most effective antidotes. However, DMSA increased the amount of cadmium retained in kidneys. The treatement of cadmium-poisoned mice with the combination of DMSA (IP) and ZnDTPA (SC) (all the compounds were injected in equimolar dose) decreased the toxicity of cadmium more than treatment with one chelating agents (given in a 2:1 dose). However, by studying the effect of these chelating agents and their combination application of the antidotes showed little or no improvement over the results obtained with the most effective of the individual components. In the urine of rats injected with CdCl 2 and treated with the chelating agents (CaDTPA, ZnDTPA, DMSA), the presence of cadmium complexes was demonstrated. The formation of mixed ligand chelates in vivo was not proved. Experiments in mice given a single injection of /sup 115m/Cd-labeled Cd complexes of DMPS, DMSA and DTPA showed a high retention of cadmium in the organisms after the IV application of CdDMPS and CdDMSA complexes

  5. Metallothionein protection of cadmium toxicity

    International Nuclear Information System (INIS)

    Klaassen, Curtis D.; Liu, Jie; Diwan, Bhalchandra A.

    2009-01-01

    The discovery of the cadmium (Cd)-binding protein from horse kidney in 1957 marked the birth of research on this low-molecular weight, cysteine-rich protein called metallothionein (MT) in Cd toxicology. MT plays minimal roles in the gastrointestinal absorption of Cd, but MT plays important roles in Cd retention in tissues and dramatically decreases biliary excretion of Cd. Cd-bound to MT is responsible for Cd accumulation in tissues and the long biological half-life of Cd in the body. Induction of MT protects against acute Cd-induced lethality, as well as acute toxicity to the liver and lung. Intracellular MT also plays important roles in ameliorating Cd toxicity following prolonged exposures, particularly chronic Cd-induced nephrotoxicity, osteotoxicity, and toxicity to the lung, liver, and immune system. There is an association between human and rodent Cd exposure and prostate cancers, especially in the portions where MT is poorly expressed. MT expression in Cd-induced tumors varies depending on the type and the stage of tumor development. For instance, high levels of MT are detected in Cd-induced sarcomas at the injection site, whereas the sarcoma metastases are devoid of MT. The use of MT-transgenic and MT-null mice has greatly helped define the role of MT in Cd toxicology, with the MT-null mice being hypersensitive and MT-transgenic mice resistant to Cd toxicity. Thus, MT is critical for protecting human health from Cd toxicity. There are large individual variations in MT expression, which might in turn predispose some people to Cd toxicity.

  6. Toxicological studies of cadmium and zinc on the crayfish Orconectes virilis

    International Nuclear Information System (INIS)

    Mirenda, R.J.

    1985-01-01

    The acute toxicities of cadmium and of zinc to the crayfish Oronectes virilis were determined. Adult, intermolt crayfish were exposed to a series of concentrations of either cadmium or zinc for a two week period. Cadmium was found to be a cumulative poison to the crayfish; LC50 values decreased from 6.1 mg Cd/I for 96 hours to 0.7 mg Cd/I for two weeks. An incipient LC50 was also estimated to be 0.0604 mg Cd/I. Zinc was found to have a relatively low toxicity to O. virilis under the present exposure conditions. Whole animal and tissue analyses for cadmium or zinc were performed on the crayfish used in the acute toxicity tests. Whole animals concentrations both for cadmium and for zinc exhibited a linear relationship to exposure concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations of cadmium and zinc, and displayed a linear relationship to exposure concentrations (r = 0.82 and 0.87 respectively). The hepatopancreas displayed a plateau in metal concentrations and is probably the main storage site for both metals in the crayfish. The relationship of cadmium concentration to exposure concentration in the antennal glands also showed linearity (r = 0.65), while zinc levels reached a steady state level. All the remaining tissues analyzed exhibited a plateau in metal concentration

  7. Isolation, identification and cadmium adsorption of a high cadmium ...

    African Journals Online (AJOL)

    The morphology was analyzed under scanning electron microscopy (SEM). The growth in the 100 mg/l cadmium medium was investigated and the biomass was analyzed by energy dispersive X-ray (EDX) spectroscopy. The results showed that strain M1 which tolerated 80 mM cadmium belong to Paecilomyces lilacinus.

  8. Isolation, identification and cadmium adsorption of a high cadmium ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... fertilizers (Udo et al., 2001). Cadmium is a non-essential element and highly toxic .... 250 ml Czapek liquid media contained 0 and 100 mg/l cadmium and were added in 500 ml shake flasks, and 1 ± 0.1 g wet ..... Fungi Intimately Associated with the Brown Seaweed Fucus serratus. Appl. Environ. Microbiol.

  9. Genotoxic effects of fumes from asphalt modified with waste plastic and tall oil pitch.

    Science.gov (United States)

    Lindberg, Hanna K; Väänänen, Virpi; Järventaus, Hilkka; Suhonen, Satu; Nygren, Jonas; Hämeilä, Mervi; Valtonen, Jarkko; Heikkilä, Pirjo; Norppa, Hannu

    2008-05-31

    As the use of recycled materials and industrial by-products in asphalt mixtures is increasing, we investigated if recycled additives modify the genotoxicity of fumes emitted from asphalt. Fumes were generated in the laboratory at paving temperature from stone-mastic asphalt (SMA) and from SMA modified with waste plastic (90% polyethylene, 10% polypropylene) and tall oil pitch (SMA-WPT). In addition, fumes from SMA, SMA-WPT, asphalt concrete (AC), and AC modified with waste plastic and tall oil pitch (AC-WPT) were collected at paving sites. The genotoxicity of the fumes was studied by analysis of DNA damage (measured in the comet assay) and micronucleus formation in human bronchial epithelial BEAS 2B cells in vitro and by counting mutations in Salmonella typhimurium strains TA98 and YG1024. DNA damage was also assessed in buccal leukocytes from road pavers before and after working with SMA, SMA-WPT, AC, and AC-WPT. The chemical composition of the emissions was analysed by gas chromatography/mass spectrometry. The SMA-WPT fume generated in the laboratory induced a clear increase in DNA damage in BEAS 2B cells without metabolic activation. The laboratory-generated SMA fume increased the frequency of micronucleated BEAS 2B cells without metabolic activation. None of the asphalt fumes collected at the paving sites produced DNA damage with or without metabolic activation. Fumes from SMA and SMA-WPT from the paving sites increased micronucleus frequency without metabolic activation. None of the asphalt fumes studied showed mutagenic activity in Salmonella. No statistically significant differences in DNA damage in buccal leukocytes were detected between the pre- and post-shift samples collected from the road pavers. However, a positive correlation was found between DNA damage and the urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) after work shift, which suggested an association between occupational exposures during road paving and genotoxic effects. Our

  10. Investigation of cadmium-induced alterations in renal glomerular function

    International Nuclear Information System (INIS)

    Long, T.J.

    1982-01-01

    This research was designed to test the hypothesis that certain aspects of cadmium-induced renal dysfunction are the result of glomerular, rather than classic tubular, injury. To determine whether cadmium-induced proteinuria was due to altered glomerular function, cadmium was administered chronically at a concentration of 185 ppm in the drinking water. This protocol resulted in the production of proteinuria which when analyzed by high pressure liquid chromatography and radioimmunoassay was indistinguishable from that occurring in control rats. Glomerular filtration rate, renal blood flow, and filtration fraction were all significantly depressed after 20-30 weeks of exposure. In order to further investigate these alterations in glomerular function, an acute exposure model was developed. It was found that a single i.p. injection of cadmium in mercaptoethanol resulted in the onset of acute renal failure. The clinical picture was characterized by a reduction in glomerular filtrate rate of 50-90% within 24 hours, with partial to total recovery occurring by day 7 post-exposure. Histological evidence indicated that to a large extent the reduction in GFR was due to tubular blockade and/or backleak of filtrate across damaged tubules

  11. Cadmium in blood and hypertension

    International Nuclear Information System (INIS)

    Eum, Ki-Do; Lee, Mi-Sun; Paek, Domyung

    2008-01-01

    Objectives:: This study is to examine the effect of cadmium exposure on blood pressure in Korean general population. Methods:: The study population consisted of 958 men and 944 women who participated in the 2005 Korean National Health and Nutrition Examination Survey (KNHANES), in which blood pressure and blood cadmium were measured from each participant. Results:: The mean blood cadmium level was 1.67 μg/L (median level 1.55). The prevalence of hypertension was 26.2%. The blood cadmium level was significantly higher among those subjects with hypertension than those without (mean level 1.77 versus 1.64 μg/dL). After adjusting for covariates, the odds ratio of hypertension comparing the highest to the lowest tertile of cadmium in blood was 1.51 (95% confidence interval 1.13 to 2.05), and a dose-response relationship was observed. Systolic, diastolic, and mean arterial blood pressure were all positively associated with blood cadmium level, and this effect of cadmium on blood pressure was markedly stronger when the kidney function was reduced. Conclusions:: Cadmium exposures at the current level may have increased the blood pressure of Korean general population

  12. Projectbeschrijving Cadmium-informatiepunt (CIP)

    NARCIS (Netherlands)

    Meijer PJ

    1989-01-01

    To minimize the use of cadmium the Central Government has decided to perform the purchase of products and materials within the Central Government as much as possible within the Draft Cadmium Decree. The activities to achieve this are as far as could be seen at the start of the project in june

  13. Experimental study, in rat wistar, of cadmium distribution and elimination as a function of administration route. Cadmium 109 maximum permissible concentration

    International Nuclear Information System (INIS)

    Valero, Marc.

    1979-01-01

    The absorption and the elimination of cadmium have been investigated in rats wistar after oral administration or after inhalation. Before studying gastro-intestinal absorption, it appeared necessary to precise acute toxicity of orally administred cadmium. The distribution of cadmium within organes was determined following a single or multiple oral doses, and we specially studied retention of a Cd dose ingested after several weeks of treatment with Cd-Acetate. Pulmonary and gastro-intestinal absorption of cadmium after ihalation of Cd-microparticles were studied. Data obtained from these studies on rats and extrapolated to man were used to calculate mximum permissible concentration (M.P.C.) of Cd-109 in water and in air [fr

  14. Cadmium exposure in the Swedish environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This report gives a thorough description of cadmium in the Swedish environment. It comprises three parts: Cadmium in Sweden - environmental risks;, Cadmium in goods - contribution to environmental exposure;, and Cadmium in fertilizers, soil, crops and foods - the Swedish situation. Separate abstracts have been prepared for all three parts

  15. Profiling mild steel welding processes to reduce fume emissions and costs in the workplace.

    Science.gov (United States)

    Keane, Michael J; Siert, Arlen; Chen, Bean T; Stone, Samuel G

    2014-05-01

    To provide quantitative information to choose the best welding processes for minimizing workplace emissions, nine gas metal arc welding (GMAW) processes for mild steel were assessed for fume generation rates, normalized fume generation rates (milligram fume per gram of electrode consumed), and normalized generation rates for elemental manganese, nickel, and iron. Shielded metal arc welding (SMAW) and flux-cored arc-welding (FCAW) processes were also profiled. The fumes were collected quantitatively in an American Welding Society-type fume chamber and weighed, recovered, homogenized, and analyzed by inductively coupled atomic emission spectroscopy for total metals. The processes included GMAW with short circuit, globular transfer, axial spray, pulsed spray, Surface Tension Transfer™, Regulated Metal Deposition™, and Cold Metal Transfer™ (CMT) modes. Flux-cored welding was gas shielded, and SMAW was a single rod type. Results indicate a wide range of fume emission factors for the process variations studied. Fume emission rates per gram of electrode consumed were highest for SMAW (~13 mg fume g(-1) electrode) and lowest for GMAW processes such as pulsed spray (~1.5mg g(-1)) and CMT (~1mg g(-1)). Manganese emission rates per gram of electrode consumed ranged from 0.45 mg g(-1) (SMAW) to 0.08 mg g(-1) (CMT). Nickel emission rates were generally low and ranged from ~0.09 (GMAW short circuit) to 0.004 mg g(-1) (CMT). Iron emission rates ranged from 3.7 (spray-mode GMAW) to 0.49 mg g(-1) (CMT). The processes studied have significantly different costs, and cost factors are presented based on a case study to allow comparisons between processes in specific cost categories. Costs per linear meter of weld were $31.07 (SMAW), $12.37 (GMAW short circuit), and $10.89 (FCAW). Although no single process is the best for minimizing fume emissions and costs while satisfying the weld requirements, there are several processes that can minimize emissions. This study provides

  16. Profiling Mild Steel Welding Processes to Reduce Fume Emissions and Costs in the Workplace

    Science.gov (United States)

    Keane, Michael J.; Siert, Arlen; Chen, Bean T.; Stone, Samuel G.

    2015-01-01

    To provide quantitative information to choose the best welding processes for minimizing workplace emissions, nine gas metal arc welding (GMAW) processes for mild steel were assessed for fume generation rates, normalized fume generation rates (milligram fume per gram of electrode consumed), and normalized generation rates for elemental manganese, nickel, and iron. Shielded metal arc welding (SMAW) and flux-cored arc-welding (FCAW) processes were also profiled. The fumes were collected quantitatively in an American Welding Society-type fume chamber and weighed, recovered, homogenized, and analyzed by inductively coupled atomic emission spectroscopy for total metals. The processes included GMAW with short circuit, globular transfer, axial spray, pulsed spray, Surface Tension Transfer™, Regulated Metal Deposition™, and Cold Metal Transfer™ (CMT) modes. Flux-cored welding was gas shielded, and SMAW was a single rod type. Results indicate a wide range of fume emission factors for the process variations studied. Fume emission rates per gram of electrode consumed were highest for SMAW (~13 mg fume g−1 electrode) and lowest for GMAW processes such as pulsed spray (~1.5 mg g−1) and CMT (~1 mg g−1). Manganese emission rates per gram of electrode consumed ranged from 0.45 mg g−1 (SMAW) to 0.08 mg g−1 (CMT). Nickel emission rates were generally low and ranged from ~0.09 (GMAW short circuit) to 0.004 mg g−1 (CMT). Iron emission rates ranged from 3.7 (spray-mode GMAW) to 0.49 mg g−1 (CMT). The processes studied have significantly different costs, and cost factors are presented based on a case study to allow comparisons between processes in specific cost categories. Costs per linear meter of weld were $31.07 (SMAW), $12.37 (GMAW short circuit), and $10.89 (FCAW). Although no single process is the best for minimizing fume emissions and costs while satisfying the weld requirements, there are several processes that can minimize emissions. This study provides

  17. Effects of Exposure to Welding Fume on Lung Function: Results from the German WELDOX Study.

    Science.gov (United States)

    Lehnert, M; Hoffmeyer, F; Gawrych, K; Lotz, A; Heinze, E; Berresheim, H; Merget, R; Harth, V; Van Gelder, R; Hahn, J-U; Hartwig, A; Weiß, T; Pesch, B; Brüning, T

    2015-01-01

    The association between exposure to welding fume and chronic obstructive pulmonary disease (COPD) has been insufficiently clarified. In this study we assessed the influence of exposure to welding fume on lung function parameters. We investigated forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, and expiratory flow rates in 219 welders. We measured current exposure to respirable particles and estimated a worker's lifetime exposure considering welding techniques, working conditions and protective measures at current and former workplaces. Multiple regression models were applied to estimate the influence of exposure to welding fume, age, and smoking on lung function. We additionally investigated the duration of working as a welder and the predominant welding technique. The findings were that age- and smoking-adjusted lung function parameters showed no decline with increasing duration, current exposure level, and lifetime exposure to welding fume. However, 15% of the welders had FEV1/FVC below the lower limit of normal, but we could not substantiate the presence of an association with the measures of exposure. Adverse effects of cigarette smoking were confirmed. In conclusion, the study did not support the notion of a possible detrimental effect of exposure to welding fume on lung function in welders.

  18. Highly Efficient Fumed Silica Nanoparticles for Peptide Bond Formation: Converting Alanine to Alanine Anhydride.

    Science.gov (United States)

    Guo, Chengchen; Jordan, Jacob S; Yarger, Jeffery L; Holland, Gregory P

    2017-05-24

    In this work, thermal condensation of alanine adsorbed on fumed silica nanoparticles is investigated using thermal analysis and multiple spectroscopic techniques, including infrared (IR), Raman, and nuclear magnetic resonance (NMR) spectroscopies. Thermal analysis shows that adsorbed alanine can undergo thermal condensation, forming peptide bonds within a short time period and at a lower temperature (∼170 °C) on fumed silica nanoparticle surfaces than that in bulk (∼210 °C). Spectroscopic results further show that alanine is converted to alanine anhydride with a yield of 98.8% during thermal condensation. After comparing peptide formation on solution-derived colloidal silica nanoparticles, it is found that fumed silica nanoparticles show much better efficiency and selectivity than solution-derived colloidal silica nanoparticles for synthesizing alanine anhydride. Furthermore, Raman spectroscopy provides evidence that the high efficiency for fumed silica nanoparticles is likely related to their unique surface features: the intrinsic high population of strained ring structures present at the surface. This work indicates the great potential of fumed silica nanoparticles in synthesizing peptides with high efficiency and selectivity.

  19. Medical Experts and Agnotology in the Fumes Controversy of the Huelva Copper Mines (1888-1890).

    Science.gov (United States)

    Guillem-Llobat, Ximo

    2017-07-01

    Huelva's copper mines (Spain) have been active for centuries but in the second half of the nineteenth century extractive activities in Riotinto, Tharsis, and other mines in the region were intensified in order to reach world leadership. The method used in these mines for copper extraction from low grade ores generated continuous emissions of fumes that were extremely controversial. The inhabitants had complained about the fumes for decades but as activity intensified so did complaints. The killing of anti-fumes demonstrators in 1888 led to the passing of a Royal Decree banning the open-air roasting of ore and to the drafting of numerous reports on the hazards of the fumes. Major state and provincial medical institutions, as well as renowned hygienists and engineers, took part in the assessment, contributing to a scientific controversy especially rich in content. In my paper I will analyse the production and circulation of knowledge and ignorance about the impact of fumes on public health, as well as the role of medical experts and expertise in the controversy. The analysis will focus on the reports drafted between the 1888 ban and its 1890 repeal, and will show the changing nature of the expert assessment and the numerous paths followed by experts in producing ignorance. The paper will conclude by considering other stakeholders, who may shed some light on the reasons behind the performance of the medical experts.

  20. Acute Respiratory Distress Syndrome (ARDS After Nitric Acid Inhalation

    Directory of Open Access Journals (Sweden)

    Gülay Kır

    2014-12-01

    Full Text Available Lung injury resulting from inhalation of chemical products continues to be associated with high morbidity and mortality. Concentrated nitric acids are also extremely corrosive fuming chemical liquids. Fumes of nitric acid (HNO3 and various oxides of nitrogen such as nitric oxide (NO and nitrogen dioxide (NO2 may cause fatal illnesses such as severe pulmonary edema and acute respiratory distress syndrome (ARDS when inhaled. Intensive respiratory management including mechanical ventilation with positive end expiratory pressure (PEEP, inverse ratio ventilation, replacement of surfactant and extracorporeal membrane oxygenation (ECMO, steroids and n-acetylcysteine (NAC may improve survival. In this case report we present the diagnosis and successful treatment of a 57 years old male patient who developed ARDS following pulmonary edema due to nitric acid fumes inhalation.

  1. Biomonitoring of cadmium in pig production

    OpenAIRE

    Lindén, Anna

    2002-01-01

    Cadmium is a nephrotoxic metal with increasing levels in arable soils. The non-smoking population is exposed to cadmium mainly from vegetable food, especially cereal products. The major part of pig feed is cereals, and accumulated cadmium in pig kidney could reflect cadmium in the local agricultural environment. In this thesis, the possibility to use pig kidney as a bioindicator of the availability of cadmium in the agricultural environment was evaluated. There were significant correlations b...

  2. Silica Fume Functionalized With Amine-Based Additives as a Modifier to Enhance Asphalt Resistance to Oxidation

    Science.gov (United States)

    Abutalib, Nader Turki

    This dissertation investigates the practical feasibility of functionalizing silica fume particles with the amine groups in Bio-binder and pure APTES chemical to disperse silica fume in asphalt binder matrix to produce silica-fume-modified binder (SFMB). Dispersed silica fume was then introduced to asphalt to reduce oxidative aging. It has been widely reported that asphalt binder oxidation is one of the phenomena that reduces the service life of asphalt pavement by negatively affecting its rheological properties. This in turn can lead to a more brittle pavement, which is more prone to cracks due to thermal stress and traffic loading. It has been shown that the introduction of 4% silica fume to asphalt can reduce asphalt oxidative aging. However, the challenge with a higher percentage of silica fume was found to be the agglomeration of nano- particles to form micro-size clusters, which can reduce the effectiveness of silica fume while making asphalt binder more susceptible to shear. Therefore, this dissertation studies the effectiveness of functionalizing the SFMB to reduce asphalt oxidative aging while alleviating the agglomeration effect. To do so, various percentages of bio-binder (BB) and bio-char (BC) were introduced to SFMB, and the rheological properties and high-temperature performance of each specimen were evaluated by measuring the rotational viscosity and complex shear modulus before and after oxidative aging. It is hypothesized that fine-graded BC and BB with nano- to micro-level particles can be used to reduce asphalt oxidation and create a new generation of low- agglomeration SFMB with higher resistance to oxidative aging. To further study the effects of functionalization on dispersion of silica fume, silica fume particles were produced with different functional groups: amine (APTES) groups and phosphonate (THPMP) groups. Agglomeration studies using a scanning electron microscope and zeta potential analysis indicate that modifying asphalt binder with

  3. Cadmium immobilization by hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Smičiklas Ivana D.

    2003-01-01

    Full Text Available The contamination of air, soil and water by cadmium is a great environmental problem. If cadmium occurs in nature in ionic form, soluble in water, it easily enters into the food chain. Hydroxyapatite (HAP, Ca-o(POAe(OH2 is a sparingly soluble salt and an excellent matrix for the removal of heavy metals from solutions. Considerable research attention has been paid to the bond between Cc/2+ ions and synthetic hydroxyapatite of known composition. The sorption mechanism is complex. The dominant process is ion exchange, but surface adsorption, surface complexation and coprecipitation can also contribute to the overall mechanism. The sorption capacity depends on the characteristics of hydroxyapatite itself and on the experimental conditions. Under optimum conditions a maximum capacity of 0.8 mol Cd2+/mol HAP can be achieved. HAP is a potential sorbent for the remediation of contaminated water and soil, for industrial waste treatment, and it is also referenced as a material that can be used as a barrier around waste depositories.

  4. Retention, distribution, and excretion of repeatedly administered cadmium-109 in the albino rat

    International Nuclear Information System (INIS)

    Shanbaky, M.M.

    1975-01-01

    This study was initiated to investigate uptake, distribution, and excretion of cadmium after prolonged intravenous and oral administrations. In both the intravenous and the oral studies cadmium was administered at 48 hr intervals for 30, 60, and 90 days to the first, second, and third animal groups, respectively. The total cadmium administered to each rat equaled 1 / 10 of the acute LD 50 (the intravenous LD 50 = 2.0 mg/kg, and the oral LD 50 = 150 mg/kg). In the excretion groups, urine and feces were collected every 48 hr during the experiment. All tissues and excreta were assayed for cadmium-109 activity by internal liquid scintillation counting. In the intravenous study the liver showed the highest cadmium retention. There were no significant differences between the mean retention values for liver in the intravenous study. Renal cadmium levels in the 120-day group were significantly higher than that of any of the other groups. In the oral study, the liver showed a mean retention of 0.90 percent on day 30, 0.96 percent on day 60, 0.68 percent on day 90, and 0.61 percent on day 120. The kidneys retained 0.13 percent, 0.19 percent, and 0.20 percent for the 30-day, 60-day, 90-day, and 120-day groups, respectively. In both the intravenous and the oral studies hepatic and renal cadmium levels were highly correlated. Cadmium excretion during the first three months of the intravenous study was cyclic in nature. After three months, about 22 percent of the total amount of intravenously administered cadmium had been excreted. In the oral study, almost all the administered cadmium was excreted

  5. Study of flow patterns in fume hood enclosures

    International Nuclear Information System (INIS)

    Pathanjali, C.; Rahman, M.M.

    1996-01-01

    A three-dimensional model for flow inside a fume hood enclosure was developed and numerical computations were carried out to explore the flow pattern and possible path of contaminant transport under different operating conditions of the hood. Equations for the conservation of mass and momentum were solved for different flow rate and opening conditions in the hood. The face velocity was maintained constant at its rated value of 0.4 m/s. The flow was assumed to enter through the front window opening (positive x-direction) and leave the cupboard through an opening on the top of the hood (positive z-direction). The flow was assumed to be fully turbulent. The κ-var-epsilon model was used for the prediction of turbulence. The flow pattern for different sash openings were studied. The flow patterns around an object located at the bottom of the hood was studied for different locations of the object. In addition, the effect of a person standing in front of the hood on the flow pattern was investigated. It was found that air entering the hood proceeds directly to the back wall, impinges it and turns upward toward the top wall and exits through the outlet. The flow finds its way around any object forming a recirculating region at its trailing surface. With an increase in the sash opening, the velocity becomes higher and the fluid traces the path to the outlet more quickly. The volume occupied by recirculating flow decreases with increase in sash opening. The computed flow patterns will be very useful to design experiments with optimum sash opening providing adequate disposal of contaminants with minimum use of conditioned air from inside the room

  6. 42 CFR 84.1152 - Silica dust loading test; respirators designed as protection against dusts, fumes, and mists...

    Science.gov (United States)

    2010-10-01

    ... AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1152... protection against dusts, fumes, and mists having an air contamination level less than 0.05 milligram per...

  7. 42 CFR 84.1141 - Isoamyl acetate tightness test; dust, fume, and mist respirators designed for respiratory...

    Science.gov (United States)

    2010-10-01

    ...; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84... mist respirators designed for respiratory protection against fumes of various metals having an air... protection against fumes of various metals having an air contamination level not less than 0.05 milligram per...

  8. 42 CFR 84.1151 - DOP filter test; respirators designed as respiratory protection against dusts, fumes, and mists...

    Science.gov (United States)

    2010-10-01

    ... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1151 DOP... respiratory protection against dusts, fumes, and mists having an air contamination level less than 0.05...

  9. A new method for infrared imaging of air currents in and around critical hazard fume hoods

    Energy Technology Data Exchange (ETDEWEB)

    Mulac, W.A.; McCreary, J.R. [Argonne National Lab., IL (United States); Schmalz, H. [Argonne National Lab., IL (United States)]|[Thermal Surveys, Inc., Rockford, IL (United States)

    1992-11-01

    A real time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods is being developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a non-toxic gas is used to render real-time video images of the presence and flow of the gas. The gas, nitrous oxide, is ejected in a continuous stream in and around fume hoods that are to be certified capable of containing hazardous fumes. The principle advantage is that various scenarios of air flow displacement in and outside the hood can be easily investigated; the principle limitation is the necessity of high tracer gas concentration to obtain strong visualizations. We hope that this technique can be found to be an effective and safe method to test hoods in locations that were built before present regulations were promulgated.

  10. A new method for infrared imaging of air currents in and around critical hazard fume hoods

    Energy Technology Data Exchange (ETDEWEB)

    Mulac, W.A.; McCreary, J.R. (Argonne National Lab., IL (United States)); Schmalz, H. (Argonne National Lab., IL (United States) Thermal Surveys, Inc., Rockford, IL (United States))

    1992-01-01

    A real time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods is being developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a non-toxic gas is used to render real-time video images of the presence and flow of the gas. The gas, nitrous oxide, is ejected in a continuous stream in and around fume hoods that are to be certified capable of containing hazardous fumes. The principle advantage is that various scenarios of air flow displacement in and outside the hood can be easily investigated; the principle limitation is the necessity of high tracer gas concentration to obtain strong visualizations. We hope that this technique can be found to be an effective and safe method to test hoods in locations that were built before present regulations were promulgated.

  11. Performance of Portland cement mixes containing silica fume and mixed with lime-water

    Directory of Open Access Journals (Sweden)

    Metwally A.A. Abd Elaty

    2014-12-01

    Test results show that using lime-water in mixing enhances consistency degree compared to the corresponding control mixes. Furthermore, it delays both initial and final setting times compared with traditional water due to the common ion effect principles. Moreover, combined use of lime-water and silica fume enhances the pozzolanic reaction that was identified by the strength development at both early and later ages. The existence of CH crystals for higher percentages of silica fume (up to 30% for further reaction at later ages was observed by XRD results. Moreover, combined use of silica fume and lime-water ensures a high alkaline media around steel bars from the moment of ingredients mixing as long as later ages despite of pozzolanic reaction that was identified from results of chloride attack.

  12. A new method for infrared imaging of air currents in and around critical hazard fume hoods

    International Nuclear Information System (INIS)

    Mulac, W.A.; McCreary, J.R.; Schmalz, H.

    1992-01-01

    A real time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods is being developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a non-toxic gas is used to render real-time video images of the presence and flow of the gas. The gas, nitrous oxide, is ejected in a continuous stream in and around fume hoods that are to be certified capable of containing hazardous fumes. The principle advantage is that various scenarios of air flow displacement in and outside the hood can be easily investigated; the principle limitation is the necessity of high tracer gas concentration to obtain strong visualizations. We hope that this technique can be found to be an effective and safe method to test hoods in locations that were built before present regulations were promulgated

  13. Testing Silica Fume-Based Concrete Composites under Chemical and Microbiological Sulfate Attacks

    Directory of Open Access Journals (Sweden)

    Adriana Estokova

    2016-04-01

    Full Text Available Current design practices based on descriptive approaches to concrete specification may not be appropriate for the management of aggressive environments. In this study, the durability of cement-based materials with and without the addition of silica fume, subjected to conditions that leach calcium and silicon, were investigated. Chemical corrosion was simulated by employing various H2SO4 and MgSO4 solutions, and biological corrosion was simulated using Acidithiobacillus sp. bacterial inoculation, leading to disrupted and damaged surfaces; the samples’ mass changes were studied following both chemical and biological attacks. Different leaching trends were observed via X-ray fluorescence when comparing chemical with biological leaching. Lower leaching rates were found for concrete samples fortified with silica fume than those without silica fume. X-ray diffraction and scanning electron microscopy confirmed a massive sulfate precipitate formation on the concrete surface due to bacterial exposure.

  14. Stabilization of heavy metals in MSWI fly ash using silica fume

    International Nuclear Information System (INIS)

    Li, Xinying; Chen, Quanyuan; Zhou, Yasu; Tyrer, Mark; Yu, Yang

    2014-01-01

    Highlights: • The stabilization of heavy metals in MSWI fly ash was investigated. • The addition of silica fume effectively reduced the leaching of Pb and Cd. • The relation of solid phase transformation and leaching behavior of heavy metals was discussed. - Abstract: The objective of this work was to investigate the feasibility and effectiveness of silica fume on stabilizing heavy metals in municipal solid waste incineration (MSWI) fly ash. In addition to compressive strength measurements, hydrated pastes were characterized by X-ray diffraction (XRD), thermal-analyses (DTA/TG), and MAS NMR ( 27 Al and 29 Si) techniques. It was found that silica fume additions could effectively reduce the leaching of toxic heavy metals. At the addition of 20% silica fume, leaching concentrations for Cu, Pb and Zn of the hydrated paste cured for 7 days decreased from 0.32 mg/L to 0.05 mg/L, 40.99 mg/L to 4.40 mg/L, and 6.96 mg/L to 0.21 mg/L compared with the MSWI fly ash. After curing for 135 days, Cd and Pb in the leachates were not detected, while Cu and Zn concentrations decreased to 0.02 mg/L and 0.03 mg/L. The speciation of Pb and Cd by the modified version of the European Community Bureau of Reference (BCR) extractions showed that these metals converted into more stable state in hydrated pastes of MSWI fly ash in the presence of silica fume. Although exchangeable and weak-acid soluble fractions of Cu and Zn increased with hydration time, silica fume addition of 10% can satisfy the requirement of detoxification for heavy metals investigated in terms of the identification standard of hazardous waste of China

  15. Experimental investigation on high performance RC column with manufactured sand and silica fume

    Science.gov (United States)

    Shanmuga Priya, T.

    2017-11-01

    In recent years, the use High Performance Concrete (HPC) has increased in construction industry. The ingredients of HPC depend on the availability and characteristics of suitable alternative materials. Those alternative materials are silica fume and manufactured sand, a by products from ferro silicon and quarry industries respectively. HPC made with silica fume as partial replacement of cement and manufactured sand as replacement of natural sand is considered as sustainable high performance concrete. In this present study the concrete was designed to get target strength of 60 MPa as per guide lines given by ACI 211- 4R (2008). The laboratory study was carried out experimentally to analyse the axial behavior of reinforced cement HPC column of size 100×100×1000mm and square in cross section. 10% of silica fume was preferred over ordinary portland cement. The natural sand was replaced by 0, 20, 40, 60, 80 and 100% with Manufactured Sand (M-Sand). In this investigation, totally 6 column specimens were cast for mixes M1 to M6 and were tested in 1000kN loading frame at 28 days. From this, Load-Mid height deflection curves were drawn and compared. Maximum ultimate load carrying capacity and the least deflection is obtained for the mix prepared by partial replacement of cement with 10% silica fume & natural sand by 100% M-Sand. The fine, amorphous and pozzalonic nature of silica fume and fine mineral particles in M- Sand increased the stiffness of HPC column. The test results revealed that HPC can be produced by using M-Sand with silica fume.

  16. Stabilization of heavy metals in MSWI fly ash using silica fume

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinying; Chen, Quanyuan [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620 (China); Zhou, Yasu [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); Tyrer, Mark [Mineral Industry Research Organisation, Solihull B37 7HB (United Kingdom); Yu, Yang [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China)

    2014-12-15

    Highlights: • The stabilization of heavy metals in MSWI fly ash was investigated. • The addition of silica fume effectively reduced the leaching of Pb and Cd. • The relation of solid phase transformation and leaching behavior of heavy metals was discussed. - Abstract: The objective of this work was to investigate the feasibility and effectiveness of silica fume on stabilizing heavy metals in municipal solid waste incineration (MSWI) fly ash. In addition to compressive strength measurements, hydrated pastes were characterized by X-ray diffraction (XRD), thermal-analyses (DTA/TG), and MAS NMR ({sup 27}Al and {sup 29}Si) techniques. It was found that silica fume additions could effectively reduce the leaching of toxic heavy metals. At the addition of 20% silica fume, leaching concentrations for Cu, Pb and Zn of the hydrated paste cured for 7 days decreased from 0.32 mg/L to 0.05 mg/L, 40.99 mg/L to 4.40 mg/L, and 6.96 mg/L to 0.21 mg/L compared with the MSWI fly ash. After curing for 135 days, Cd and Pb in the leachates were not detected, while Cu and Zn concentrations decreased to 0.02 mg/L and 0.03 mg/L. The speciation of Pb and Cd by the modified version of the European Community Bureau of Reference (BCR) extractions showed that these metals converted into more stable state in hydrated pastes of MSWI fly ash in the presence of silica fume. Although exchangeable and weak-acid soluble fractions of Cu and Zn increased with hydration time, silica fume addition of 10% can satisfy the requirement of detoxification for heavy metals investigated in terms of the identification standard of hazardous waste of China.

  17. Autogenous Deformation and Change of the Relative Humidity in Silica Fume-Modified Cement Paste

    DEFF Research Database (Denmark)

    Jensen, Ole mejlhede; Hansen, Per Freiesleben

    1996-01-01

    Even during sealed curing and at a constant temperature a hardening cement paste will deform and the relative humidity within its pores will lower. This autogenous deformation and autogenous relative humidity change may be so significant that the cement paste cracks if the deformation is restrained....... This article focuses on the influence of silica fume addition on autogenous deformation and autogenous relative humidity change. Continuous measurement of autogenous deformation and autogenous relative humidity change for more than 1 year and 1« years, respectively, was performed. The investigations show...... thatsilica fume addition markedly increases the autogenous shrinkage as well as the autogenous relative humidity change....

  18. Dynamic Moisture Sorption and Desorption in Fumed Silica-filled Silicone Foam

    Energy Technology Data Exchange (ETDEWEB)

    Trautschold, Olivia Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-02

    Characterizing dynamic moisture sorption and desorption in fumed silica-filled silicone foam is necessary for determining material compatibilities and life predictions, particularly in sealed environments that may be exposed to a range of environmental conditions. Thermogravimetric analysis (TGA) and near infrared spectroscopy (NIR) were performed on S5470 fumed silica-filled silicone foam to determine the weight percent of moisture at saturation. Additionally, TGA was used to determine the time, temperature, and relative humidity levels required for sorption and desorption of physisorbed moisture in S5470.

  19. Transport and Deposition of Welding Fume Agglomerates in a Realistic Human Nasal Airway.

    Science.gov (United States)

    Tian, Lin; Inthavong, Kiao; Lidén, Göran; Shang, Yidan; Tu, Jiyuan

    2016-07-01

    Welding fume is a complex mixture containing ultra-fine particles in the nanometer range. Rather than being in the form of a singular sphere, due to the high particle concentration, welding fume particles agglomerate into long straight chains, branches, or other forms of compact shapes. Understanding the transport and deposition of these nano-agglomerates in human respiratory systems is of great interest as welding fumes are a known health hazard. The neurotoxin manganese (Mn) is a common element in welding fumes. Particulate Mn, either as soluble salts or oxides, that has deposited on the olfactory mucosa in human nasal airway is transported along the olfactory nerve to the olfactory bulb within the brain. If this Mn is further transported to the basal ganglia of the brain, it could accumulate at the part of the brain that is the focal point of its neurotoxicity. Accounting for various dynamic shape factors due to particle agglomeration, the current computational study is focused on the exposure route, the deposition pattern, and the deposition efficiency of the inhaled welding fume particles in a realistic human nasal cavity. Particular attention is given to the deposition pattern and deposition efficiency of inhaled welding fume agglomerates in the nasal olfactory region. For particles in the nanoscale, molecular diffusion is the dominant transport mechanism. Therefore, Brownian diffusion, hydrodynamic drag, Saffman lift force, and gravitational force are included in the model study. The deposition efficiencies for single spherical particles, two kinds of agglomerates of primary particles, two-dimensional planar and straight chains, are investigated for a range of primary particle sizes and a range of number of primary particles per agglomerate. A small fraction of the inhaled welding fume agglomerates is deposited on the olfactory mucosa, approximately in the range 0.1-1%, and depends on particle size and morphology. The strong size dependence of the deposition

  20. Phase analysis of fume during arc weld brazing of steel sheets with protective coatings

    Directory of Open Access Journals (Sweden)

    J. Matusiak

    2016-04-01

    Full Text Available The article presents the results of research of the phase identification and of the quantitative phase analysis of fume generated during Cold Metal Transfer (CMT, ColdArc and Metal Inert Gas / Metal Active Gas (MIG / MAG weld brazing. Investigations were conducted for hot - dip coated steel sheets with zinc (Zn and zinc-iron (Zn - Fe alloy coatings. Arc shielding gases applied during the research-related tests were Ar + O2, Ar + CO2, Ar + H2 and Ar + CO2 + H2 gas mixtures. The analysis of the results covers the influence of the chemical composition of shielding gas on the chemical composition of welding fume.

  1. Cadmium effects on the thyroid gland.

    Science.gov (United States)

    Jancic, Snezana A; Stosic, Bojan Z

    2014-01-01

    Cadmium has been listed as one of the 126 priority pollutants and a category I carcinogen. Carcinogenic effects of cadmium on the lungs, testicles, and prostate are widely recognized, but there has been insufficient research on the effect of cadmium on the thyroid gland. Cadmium has the affinity to accumulate not only in the liver, kidneys, and pancreas but also in the thyroid gland. It has been established that cadmium blood concentration correlates positively with its accumulation in the thyroid gland. Women of fertile age have higher cadmium blood and urine concentrations than men. In spite of its redox inertia, cadmium brings about oxidative stress and damage to the tissue by indirect mechanisms. Mitochondria are considered to be the main intracellular targets for cadmium. Colloid cystic goiter, adenomatoid follicular hyperplasia with low-grade dysplasia and thyroglobulin hypo- and asecretion, and parafollicular cell diffuse and nodular hyperplasia and hypertrophy are often found in chronic cadmium toxicity. © 2014 Elsevier Inc. All rights reserved.

  2. Cadmium-containing waste and recycling possibilities

    International Nuclear Information System (INIS)

    Wiegand, V.; Rauhut, A.

    1981-01-01

    To begin with, the processes of cadmium production from zinc ores in smelting plants or from intermediates of other metal works are described. A considerable amount of the cadmium is obtained in the recycling process in zinc, lead, and copper works. The way of the cadmium-containing intermediaries, processing, enrichment, and disposal of cadmium waste are described. Uses of cadmium and its compounds are mentioned, and cadmium consumption in the years 1973-1977 in West Germany is presented in a table. Further chapters discuss the production and the way of waste during production and processing of cadmium-containing products, the problem of cadmium in household refuse and waste incineration plants, and the problem of cadmium emissions. (IHOE) [de

  3. Discovery of the cadmium isotopes

    International Nuclear Information System (INIS)

    Amos, S.; Thoennessen, M.

    2010-01-01

    Thirty-seven cadmium isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  4. Lead and cadmium in wild birds in southeastern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Fernandez, A.J.; Sanchez-Garcia, J.A.; Luna, A. [Univ. of Murcia (Spain); Jimenez-Montalban, P. [Regional Environmental Agency, Murcia (Spain). Centro de Recuperacion de Fauna Silvestre El Valle

    1995-12-01

    The main purpose of this study was to monitor exposure to lead and cadmium in wild birds in Murcia, a southeastern region of Spain on the Mediterranean coast. This region lies on one of the African-European flyways. Samples of liver, kidney, brain, bone, and whole blood from several species of wild birds were obtained during 1993. The authors found a clear relationship between cadmium and lead concentrations in birds and their feedings habits. Vultures (Gyps fulvus) had the highest concentrations of lead (mean 40 {micro}g/dl in blood), and seagulls (Larus argentatus and Larus ridibundus) the highest concentrations of cadmium (mean 4.43 {micro}g/g in kidney). Insectivores had high concentrations of both metals, and diurnal and nocturnal raptors showed the lowest tissue concentrations. The findings that tissue and blood concentrations were generally not elevated suggests environmental (rather than acute) exposure. Birds from more industrialized areas of the region studied here had higher concentrations of both lead and cadmium.

  5. Cadmium determination in wrapping paper

    Energy Technology Data Exchange (ETDEWEB)

    Ostapczuk, P. (Institute of Applied Physical Chemistry, Research Center Juelich (Germany)); Knezevic, G. (Fraunhofer Inst. fuer Verpackung und Lebensmitteltechnologie, Muenchen (Germany)); Matter, L. (Chemisches und Lebensmitteluntersuchungsamt der Stadt Duisburg (Germany)); Steinle, G. (Suedzucker AG, Gruenstadt (Germany))

    1993-01-01

    The determination of cadmium in wrapping paper was carried out by the 'Inorganic Constituents' working group in an interlaboratory comparison. Pressure digestion in PTFE bombs and high pressure ashing in quartz vessels with nitric acid were used. Eleven participants used ET AAS and only two DPASV for cadmium determination. The mean of all (13) participants was 0.059 [+-] 0.027 mg/kg. Individual data are presented. (orig.).

  6. Influence of welding fume on systemic iron status.

    Science.gov (United States)

    Casjens, Swaantje; Henry, Jana; Rihs, Hans-Peter; Lehnert, Martin; Raulf-Heimsoth, Monika; Welge, Peter; Lotz, Anne; Gelder, Rainer Van; Hahn, Jens-Uwe; Stiegler, Hugo; Eisele, Lewin; Weiss, Tobias; Hartwig, Andrea; Brüning, Thomas; Pesch, Beate

    2014-11-01

    Iron is the major metal found in welding fumes, and although it is an essential trace element, its overload causes toxicity due to Fenton reactions. To avoid oxidative damage, excess iron is bound to ferritin, and as a result, serum ferritin (SF) is a recognized biomarker for iron stores, with high concentrations linked to inflammation and potentially also cancer. However, little is known about iron overload in welders. Within this study, we assessed the iron status and quantitative associations between airborne iron, body iron stores, and iron homeostasis in 192 welders not wearing dust masks. Welders were equipped with personal samplers in order to determine the levels of respirable iron in the breathing zone during a working shift. SF, prohepcidin and other markers of iron status were determined in blood samples collected after shift. The impact of iron exposure and other factors on SF and prohepcidin were estimated using multiple regression models. Our results indicate that respirable iron is a significant predictor of SF and prohepcidin. Concentrations of SF varied according to the welding technique and respiratory protection used, with a median of 103 μg l(-1) in tungsten inert gas welders, 125 μg l(-1) in those wearing air-purifying respirators, and 161 μg l(-1) in other welders. Compared to welders with low iron stores (SF < 25 μg l(-1)), those with excess body iron (SF ≥ 400 μg l(-1)) worked under a higher median concentration of airborne iron (60 μg m(-3) versus 148 μg m(-3)). Even though air concentrations of respirable iron and manganese were highly correlated, and low iron stores have been reported to increase manganese uptake in the gastrointestinal tract, no correlation was seen between SF and manganese in blood. In conclusion, monitoring SF may be a reasonable method for health surveillance of welders. Respiratory protection with air-purifying respirators can decrease iron exposure and avoid chronically higher SF in welders working with

  7. Biological indicators of cadmium exposure and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, Z.A.; Smith, L.M.

    1986-01-01

    The increasing environmental and occupational exposure of populations to cadmium creates the need for biological indicators of cadmium exposure and toxicity. The advantages and disadvantages of monitoring blood cadmium, urinary, fecal, hair, and tissue cadmium, serum creatine, beta 2-microglobulin, alpha 1-anti-trypsin and other proteins, and urinary amino acids, enzymes, total proteins, glucose, beta 2-microglobulin, retinol-binding protein, lysozyme, and metallothionein are discussed. It is concluded that urinary cadmium, metallothionein and beta 2-microglubulin may be used together to assess cadmium exposure and toxicity. 66 references.

  8. Relationship between welding fume concentration and systemic inflammation after controlled exposure of human subjects with welding fumes from metal inert gas brazing of zinc-coated materials.

    Science.gov (United States)

    Brand, Peter; Bauer, Marcus; Gube, Monika; Lenz, Klaus; Reisgen, Uwe; Spiegel-Ciobanu, Vilia Elena; Kraus, Thomas

    2014-01-01

    It has been shown that exposure of subjects to emissions from a metal inert gas (MIG) brazing process of zinc-coated material led to an increase of high-sensitivity C-reactive protein (hsCRP) in the blood. In this study, the no-observed-effect level (NOEL) for such emissions was assessed. Twelve healthy subjects were exposed for 6 hours to different concentrations of MIG brazing fumes under controlled conditions. High-sensitivity C-reactive protein was measured in the blood. For welding fumes containing 1.20 and 1.50 mg m zinc, high-sensitivity C-reactive protein was increased the day after exposure. For 0.90 mg m zinc, no increase was detected. These data indicate that the no-observed-effect level for emissions from a MIG brazing process of zinc-coated material in respect to systemic inflammation is found for welding fumes with zinc concentrations between 0.90 and 1.20 mg m.

  9. [Evaluation of measurement uncertainty of welding fume in welding workplace of a shipyard].

    Science.gov (United States)

    Ren, Jie; Wang, Yanrang

    2015-12-01

    To evaluate the measurement uncertainty of welding fume in the air of the welding workplace of a shipyard, and to provide quality assurance for measurement. According to GBZ/T 192.1-2007 "Determination of dust in the air of workplace-Part 1: Total dust concentration" and JJF 1059-1999 "Evaluation and expression of measurement uncertainty", the uncertainty for determination of welding fume was evaluated and the measurement results were completely described. The concentration of welding fume was 3.3 mg/m(3), and the expanded uncertainty was 0.24 mg/m(3). The repeatability for determination of dust concentration introduced an uncertainty of 1.9%, the measurement using electronic balance introduced a standard uncertainty of 0.3%, and the measurement of sample quality introduced a standard uncertainty of 3.2%. During the determination of welding fume, the standard uncertainty introduced by the measurement of sample quality is the dominant uncertainty. In the process of sampling and measurement, quality control should be focused on the collection efficiency of dust, air humidity, sample volume, and measuring instruments.

  10. Exposure of welders to fumes, Cr, Ni, Cu and gases in Dutch industries

    NARCIS (Netherlands)

    Wal, J.F. van der

    1985-01-01

    The exposure of welders in Dutch industries to total particulate, chromium, nickel and copper fume during the welding of unalloyed, stainless and high alloyed steels has been investigated. The exposure to the gases NO2, NO and ozone is also discussed. The results are presented in tables and graphs.

  11. Effect Of Inhalation Exposure To Kerosene And Petrol-Fumes On ...

    African Journals Online (AJOL)

    Changes in total body weight, some anaemia-diagnostic indices (haematocrit or packed cell volume (PCV), haemoglobin (Hb) and total serum protein) were determined in rats (Wistar albino strain) after 2 weeks of 4 hours daily inhalation exposure to ungraded concentrations of kerosene and petrol fumes. The results ...

  12. Blunted behavioral and c Fos responses to acidic fumes in the African naked mole-rat.

    Science.gov (United States)

    LaVinka, Pamela Colleen; Park, Thomas J

    2012-01-01

    Acidosis in the skin triggers activation of pain pathways and behaviors indicative of pain in vertebrates. The exception is the naked mole-rat, the only known vertebrate to show physiological and behavioral insensitivity to acid pain in the skin. The goal of the present study was to determine behavioral and physiological responses of this species to airborne acidic fumes, which would be expected to affect the trigeminal pain pathway in other species. Behaviorally, naked mole-rats did not avoid fumes from moderately high concentrations of acetic acid (10 and 20%), and c Fos labeling showed no increase in activity in the trigeminal nuclei and nucleus tractus solitarius. In contrast, these concentrations triggered behavioral aversion and increased Fos activity in other laboratory rodents. For a very high concentration of acetic acid (50%), naked mole-rats showed significant avoidance behavior and increased Fos labeling in the nucleus tractus solitarius caudal region, which receives vagal chemosensory information. However, there was no increase in trigeminal labeling, and in fact, activity significantly decreased. This pattern is opposite of that associated with another irritant, ammonia fumes, which elicited an increase in trigeminal but not nucleus tractus solitarius Fos labeling, and no behavioral avoidance. Behavioral avoidance of acidic fumes, but no increased labeling in the trigeminal pain nucleus is consistent with the notion of adaptations to blunt acid pain, which would be advantageous for naked mole-rats as they normally live under chronically high levels of acidosis-inducing CO(2).

  13. Blunted behavioral and c Fos responses to acidic fumes in the African naked mole-rat.

    Directory of Open Access Journals (Sweden)

    Pamela Colleen LaVinka

    Full Text Available Acidosis in the skin triggers activation of pain pathways and behaviors indicative of pain in vertebrates. The exception is the naked mole-rat, the only known vertebrate to show physiological and behavioral insensitivity to acid pain in the skin. The goal of the present study was to determine behavioral and physiological responses of this species to airborne acidic fumes, which would be expected to affect the trigeminal pain pathway in other species. Behaviorally, naked mole-rats did not avoid fumes from moderately high concentrations of acetic acid (10 and 20%, and c Fos labeling showed no increase in activity in the trigeminal nuclei and nucleus tractus solitarius. In contrast, these concentrations triggered behavioral aversion and increased Fos activity in other laboratory rodents. For a very high concentration of acetic acid (50%, naked mole-rats showed significant avoidance behavior and increased Fos labeling in the nucleus tractus solitarius caudal region, which receives vagal chemosensory information. However, there was no increase in trigeminal labeling, and in fact, activity significantly decreased. This pattern is opposite of that associated with another irritant, ammonia fumes, which elicited an increase in trigeminal but not nucleus tractus solitarius Fos labeling, and no behavioral avoidance. Behavioral avoidance of acidic fumes, but no increased labeling in the trigeminal pain nucleus is consistent with the notion of adaptations to blunt acid pain, which would be advantageous for naked mole-rats as they normally live under chronically high levels of acidosis-inducing CO(2.

  14. The Renal Toxicity of Welding Fumes in Heavy Equipment Manufacturer Workers

    Directory of Open Access Journals (Sweden)

    Mulyana

    2015-09-01

    Full Text Available Exposure to welding fumes in the workplace has been associated with decreasing renal function. We studied renal function parameters in men workers from heavy equipment manufacturer exposed to welding fumes. This study aimed to evaluate renal function status among worker exposed to welding fumes. A case-control design, random study, was conducted among welder (35 subjects and non welder (35 subjects with more than 1 years experience in the same job task in a heavy equipment manufacturer. All subjects were completed physical examination, informed consent, questionnaire and laboratory tests. Renal function was measured as creatinine serum using enzimatic method. Urinary heavy metals level was analyzed using inductively coupled plasma mass spectrometry. Comparisson analysis between group was performed to determined median level for each variable. Linear regression model was developed to predict renal function function parameter status urinary heavy metals level as variable. This study showed there were higher creatinine serum, chromium, iron, manganese and nickel in welder than non welder(p<0.05. After multivariate analysis, urinary nickel is a predictor for renal function status among welder. Exposure to welding fumes was significantly correlated with renal function status in welder. Nickel is the predictive variable for renal function. Although statistically significant but in clinical field needs carefully interpreting data.

  15. Effect of Silica fume and superplasticizer on steel-concrete bond

    International Nuclear Information System (INIS)

    Esfahani, M. R.

    2001-01-01

    This paper presents a study on the influence of silica fume and super plasticizer on bond strength. The study included tests of fifty short length pull-out specimens in five series. The effect of silica fume and super plasticizer on bond strength was evaluated separately by tests of specimens made of concretes with similar strengths but different admixtures. Test results showed that the addition of silica fume in the concrete mixture had not a negative effect on bond strength. Also, there was not a considerable decrease in bond strength of specimens made of concrete with super plasticizer. Comparing the measured bond strengths normalized with respect to the square root of the concrete compressive strength, it was seen that the normalized bond strength increased with the concrete strength. this result agrees with the model previously proposed by the author for local bond strength. For the specimens made of high strength concrete including silica fume and super plasticizer, the normalized bond strength did not increase with the concrete strength

  16. Low Temperature Synthesis of Belite Cement Based on Silica Fume and Lime.

    Science.gov (United States)

    Tantawy, M A; Shatat, M R; El-Roudi, A M; Taher, M A; Abd-El-Hamed, M

    2014-01-01

    This paper describes the low temperature synthesis of belite (β-C2S) from silica fume. Mixtures of lime, BaCl2, and silica fume with the ratio of (Ca + Ba)/Si = 2 were hydrothermally treated in stainless steel capsule at 110-150°C for 2-5 hours, calcined at 600-700°C for 3 hours, and analyzed by FTIR, XRD, TGA/DTA, and SEM techniques. Dicalcium silicate hydrate (hillebrandite) was prepared by hydrothermal treatment of lime/silica fume mixtures with (Ca + Ba)/Si = 2 at 110°C for 5 hours. Hillebrandite partially dehydrates in two steps at 422 and 508°C and transforms to γ-C2S at 734°C which in turn transforms to α'-C2S at 955°C which in turn transforms to β-C2S when cooled. In presence of Ba(2+) ions, β-C2S could be stabilized with minor transformation to γ-C2S. Mixture of silica fume, lime, and BaCl2 with the ratio of (Ca + Ba)/Si = 2 was successfully utilized for synthesis of β-C2S by hydrothermal treatment at 110°C for 5 hours followed by calcination of the product at 700°C for 3 hours.

  17. Effect of silica fume on compressive strength of oil-polluted concrete in different marine environments

    Science.gov (United States)

    Shahrabadi, Hamid; Sayareh, Sina; Sarkardeh, Hamed

    2017-12-01

    In the present research, effect of silica fume as an additive and oil polluted sands as aggregates on compressive strength of concrete were investigated experimentally. The amount of oil in the designed mixtures was assumed to be constant and equal to 2% of the sand weight. Silica fume accounting for 10%, 15% and 20% of the weight is added to the designed mixture. After preparation and curing, concrete specimens were placed into the three different conditions: fresh, brackish and saltwater environments (submerged in fresh water, alternation of exposed in air & submerged in sea water and submerged in sea water). The result of compressive strength tests shows that the compressive strength of the specimens consisting of silica fume increases significantly in comparison with the control specimens in all three environments. The compressive strength of the concrete with 15% silica fume content was about 30% to 50% higher than that of control specimens in all tested environments under the condition of using polluted aggregates in the designed mixture.

  18. A novel method for assessing respiratory deposition of welding fume nanoparticles.

    Science.gov (United States)

    Cena, L G; Keane, M J; Chisholm, W P; Stone, S; Harper, M; Chen, B T

    2014-01-01

    Welders are exposed to high concentrations of nanoparticles. Compared to larger particles, nanoparticles have been associated with more toxic effects at the cellular level, including the generation of more reactive oxygen species activity. Current methods for welding-fume aerosol exposures do not differentiate between the nano-fraction and the larger particles. The objectives of this work are to establish a method to estimate the respiratory deposition of the nano-fraction of selected metals in welding fumes and test this method in a laboratory setting. Manganese (Mn), Nickel (Ni), Chromium (Cr), and hexavalent chromium (Cr(VI)) are commonly found in welding fume aerosols and have been linked with severe adverse health outcomes. Inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography (IC) were evaluated as methods for analyzing the content of Mn, Ni, Cr, and Cr(VI) nanoparticles in welding fumes collected with nanoparticle respiratory deposition (NRD) samplers. NRD samplers collect nanoparticles at deposition efficiencies that closely resemble physiological deposition in the respiratory tract. The limits of detection (LODs) and quantitation (LOQs) for ICP-MS and IC were determined analytically. Mild and stainless steel welding fumes generated with a robotic welder were collected with NRD samplers inside a chamber. LODs (LOQs) for Mn, Ni, Cr, and Cr(VI) were 1.3 μg (4.43 μg), 0.4 μg (1.14 μg), 1.1 μg (3.33 μg), and 0.4 μg (1.42 μg), respectively. Recovery of spiked samples and certified welding fume reference material was greater than 95%. When testing the method, the average percentage of total mass concentrations collected by the NRD samplers was ~30% for Mn, ~50% for Cr, and ~60% for Ni, indicating that a large fraction of the metals may lie in the nanoparticle fraction. This knowledge is critical to the development of toxicological studies aimed at finding links between exposure to welding fume nanoparticles and adverse health

  19. PEMANFAATAN LIMBAH SERBUK MARMER PADA BETON SEBAGAI BAHAN PENGGANTI SEBAGIAN SEMEN DENGAN VARIASI PENGGUNAAN SILICA FUME

    Directory of Open Access Journals (Sweden)

    Agil Fitri Handayani

    2015-02-01

    Full Text Available The Utilization of Marble Powder Waste in Concrete Ma­­­­­­­­terials as a Partial Material Substitution of Cement  with the Variation Use of Silica Fume. The purpose of this study was to determine the effect of marble powder and silica fume on the mechanical pro­per­ties of concrete. This study used an experimental design using 16 group of testing materials with variety types of mixtures between marble powder and silica fume 0.00; 5.00; 10.00; and 15.00%. The wa­ter-cement ratio was 0.50 and a low dosage of superplasticizer, which was 0.50%. The behavior of fresh concrete were calculated and the mechanical properties of concrete were tested on con­crete age of 28 days. The results showed the marble powder main com­position was Silicon Dioxide (SiO2 17.63% and Calcium Carbonate (CaCO3 2.73%. Mar­ble powder was more appropriate to be used as fillers than to be used as a partial substitution of ce­ment. The optimum mechanical properties of concrete was produced by the mixtures of 5.00% mar­ble powder  and 6.22% silica fume which resulted in compressive strength of 29.04 MPa.   Tujuan penelitian ini adalah untuk mengetahui pengaruh peng­gunaan ser­buk marmer dan silica fume terhadap sifat mekanik beton. Penelitian ini meng­gu­na­kan desain eksperimen dengan 16 kelompok benda uji dengan variasi ser­buk marmer dan silica fume 0,00; 5,00; 10,00; dan 15,00%. Faktor air semen di­gu­nakan 0,50 dan superplasticizer dengan dosis rendah 0,50%. Perilaku beton segar di­perhitungkan dan sifat mekanik beton diuji pada umur beton 28 hari. Hasil analisis me­nunjukkan kom­posisi utama serbuk marmer adalah Silikon Dioksida (SiO2 17,63% dan Kalsium Kar­bonat (CaCO3 2,73%. Serbuk marmer lebih tepat digunakan se­bagai bahan pe­ng­isi atau filler dari pada sebagai pengganti semen. Sifat mekanik be­ton optimum di­ha­sil­kan pada campuran serbuk marmer 5,00% dan silica fume 6,22% dengan kuat tekan be­ton yang dihasilkan  mencapai 29

  20. Welding fumes from stainless steel gas metal arc processes contain multiple manganese chemical species.

    Science.gov (United States)

    Keane, Michael; Stone, Samuel; Chen, Bean

    2010-05-01

    Fumes from a group of gas metal arc welding (GMAW) processes used on stainless steel were generated using three different metal transfer modes and four different shield gases. The objective was to identify and measure manganese (Mn) species in the fumes, and identify processes that are minimal generators of Mn species. The robotic welding system was operated in short-circuit (SC) mode (Ar/CO2 and He/Ar), axial spray (AXS) mode (Ar/O2 and Ar/CO2), and pulsed axial-spray (PAXS) mode (Ar/O2). The fumes were analyzed for Mn by a sequential extraction process followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, and by X-ray diffraction (XRD). Total elemental Mn, iron (Fe), chromium (Cr) and nickel (Ni) were separately measured after aqua regia digestion and ICP-AES analysis. Soluble Mn2+, Fe2+, Fe3+, and Ni2+ in a simple biological buffer (phosphate-buffered saline) were determined at pH 7.2 and 5.0 after 2 h incubation at 37 C by ion chromatography. Results indicate that Mn was present in soluble form, acid-soluble form, and acid-soluble form after reduction by hydroxylamine, which represents soluble Mn0 and Mn2+ compounds, other Mn2+ compounds, and (Mn3+ and Mn4+) compounds, respectively. The dominant fraction was the acid-soluble Mn2+ fraction, but results varied with the process and shield gas. Soluble Mn mass percent in the fume ranged from 0.2 to 0.9%, acid-soluble Mn2+ compounds ranged from 2.6 to 9.3%, and acid plus reducing agent-soluble (Mn3+ and Mn4+) compounds ranged from 0.6 to 5.1%. Total Mn composition ranged from 7 to 15%. XRD results showed fumes had a crystalline content of 90-99% Fe3O4, and showed evidence of multiple Mn oxides, but overlaps and weak signals limited identification. Small amounts of the Mn2+ in the fume (welding process. Mn generation rates for the fractions were tabulated, and the influence of ozone is discussed. The conclusions are that exposures to welding fumes include multiple Mn species, both

  1. Effects of waterborne cadmium on metabolic rate, oxidative stress, and ion regulation in the freshwater fish, inanga (Galaxias maculatus).

    Science.gov (United States)

    McRae, Nicole K; Gaw, Sally; Glover, Chris N

    2018-01-01

    The freshwater fish Galaxias maculatus (inanga) is a widespread Southern hemisphere species, but despite its habitation of lowland near-coastal waters with a high potential for cadmium contamination, nothing is known regarding its sensitivity to this toxic trace metal. Acute (96h) exposures were therefore performed to determine sublethal responses of inanga to waterborne cadmium at a regulatory trigger value (nominally 0.2μgL -1 ; measured 1μgL -1 ), an environmental level (measured at 2.5μgL -1 ), and an effect level (measured at 10μgL -1 ). Whole body (tissue remaining following excision of kidney and liver) cadmium burden remained constant up until an exposure concentration of 10μgL -1 , at which point cadmium concentration increased significantly. A transient effect of cadmium on metabolic rate was observed, with an impaired oxygen consumption noted at 2.5, but not 1 or 10, μg L -1 . Cadmium did not impair influx rates of either sodium or calcium, and no effects of cadmium on oxidative stress parameters (catalase activity, lipid peroxidation) were noted in the kidney. However, at cadmium concentrations of 2.5 and 10μgL -1 , lipid peroxidation in the liver increased, concomitant with a decline in hepatic catalase activity. These data indicate that there are significant differences in the mechanisms of cadmium toxicity in inanga, relative to better-studied Northern hemisphere species, especially with respect to ionoregulatory impacts. However, effects were induced at cadmium concentrations unlikely to be encountered in any but the most highly contaminated waterways, and thus our data suggest that current trigger values for cadmium concentrations in Australian and New Zealand waters are likely to be protective of inanga. Copyright © 2017. Published by Elsevier B.V.

  2. Zinc-induced protection against cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Early, J.L.; Schnell, R.C.

    1978-02-01

    Pretreatment of male rats with cadmium acetate potentiates the duration of hexobarbital hypnosis and inhibits the rate of hepatic microsomal drug metabolism. Pretreatment of rats with zinc acetate protects against these alterations in drug action elicited by cadmium.

  3. Uptake and distribution of cadmium in corn

    International Nuclear Information System (INIS)

    Peel, J.W.; Vetter, R.J.; Christian, J.E.; Kessler, W.V.; McFee, W.W.

    1978-01-01

    The uptake and distribution of cadmium in corn (Zea mays) treated at various time intervals after planting and sampled at various times after treatment were measured. Cadmium was found to accumulate in all parts sampled. As shown in field studies, stems and leaves generally concentrated more cadmium than did husks, cobs, kernels, silks, or tassels. Samples of stems and leaves from corn treated 23 days after planting and sampled 5 days later exhibited higher concentrations of cadmium than samples taken 25, 45, 65, or 85 days after treatment. Concentrations generally decreased with time. Greenhouse studies showed that corn exposed to cadmium for the longest period of time accumulated the greatest total cadmium. The highest cadmium concentrations were found in the base or lowest leaves sampled 45 days after planting; this suggests a useful technique for quick screening corn crops for cadmium pollution

  4. Physicochemical and toxicological characteristics of welding fume derived particles generated from real time welding processes.

    Science.gov (United States)

    Chang, Cali; Demokritou, Philip; Shafer, Martin; Christiani, David

    2013-01-01

    Welding fume particles have been well studied in the past; however, most studies have examined welding fumes generated from machine models rather than actual exposures. Furthermore, the link between physicochemical and toxicological properties of welding fume particles has not been well understood. This study aims to investigate the physicochemical properties of particles derived during real time welding processes generated during actual welding processes and to assess the particle size specific toxicological properties. A compact cascade impactor (Harvard CCI) was stationed within the welding booth to sample particles by size. Size fractionated particles were extracted and used for both off-line physicochemical analysis and in vitro cellular toxicological characterization. Each size fraction was analyzed for ions, elemental compositions, and mass concentration. Furthermore, real time optical particle monitors (DustTrak™, TSI Inc., Shoreview, Minn.) were used in the same welding booth to collect real time PM2.5 particle number concentration data. The sampled particles were extracted from the polyurethane foam (PUF) impaction substrates using a previously developed and validated protocol, and used in a cellular assay to assess oxidative stress. By mass, welding aerosols were found to be in coarse (PM 2.5–10), and fine (PM 0.1–2.5) size ranges. Most of the water soluble (WS) metals presented higher concentrations in the coarse size range with some exceptions such as sodium, which presented elevated concentration in the PM 0.1 size range. In vitro data showed size specific dependency, with the fine and ultrafine size ranges having the highest reactive oxygen species (ROS) activity. Additionally, this study suggests a possible correlation between welders' experience, the welding procedure and equipment used and particles generated from welding fumes. Mass concentrations and total metal and water soluble metal concentrations of welding fume particles may be

  5. Alterations in cardiomyocyte function after pulmonary treatment with stainless steel welding fume in rats.

    Science.gov (United States)

    Popstojanov, Risto; Antonini, James M; Salmen, Rebecca; Ye, Morgan; Zheng, Wen; Castranova, Vincent; Fekedulegn, Desta B; Kan, Hong

    2014-01-01

    Welding fume is composed of a complex of different metal particulates. Pulmonary exposure to different welding fumes may exert a negative impact on cardiac function, although the underlying mechanisms remain unclear. To explore the effect of welding fumes on cardiac function, Sprague-Dawley rats were exposed by intratracheal instillation to 2 mg/rat of manual metal arc hard surfacing welding fume (MMA-HS) once per week for 7 wk. Control rats received saline. Cardiomyocytes were isolated enzymatically at d 1 and 7 postexposure. Intracellular calcium ([Ca(2+)]i) transients (fluorescence ratio) were measured on the stage of an inverted phase-contrast microscope using a myocyte calcium imaging/cell length system. Phosphorylation levels of cardiac troponin I (cTnI) were determined by Western blot. The levels of nonspecific inflammatory marker C-reactive protein (CRP) and proinflammatory cytokine interleukin-6 (IL-6) in serum were measured by enzyme-linked immunosorbent assay (ELISA). Contraction of isolated cardiomyocytes was significantly reduced at d 1 and d 7 postexposure. Intracellular calcium levels were decreased in response to extracellular calcium stimulation at d 7 postexposure. Changes of intracellular calcium levels after isoprenaline hydrochloride (ISO) stimulation were not markedly different between groups at either time point. Phosphorylation levels of cTnI in the left ventricle were significantly lower at d 1 postexposure. The serum levels of CRP were not markedly different between groups at either time point. Serum levels of IL-6 were not detectable in both groups. Cardiomyocyte alterations observed after welding fume treatment were mainly due to alterations in intracellular calcium handling and phosphorylation levels of cTnI.

  6. Effects on the efficiency of activated carbon on exposure to welding fumes

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, D. [Southern Company Services, Inc., Birmingham, AL (United States)

    1995-02-01

    It is the intention of this paper to document that certain types of welding fumes have little or no effect on the effectiveness of the carbon filter air filtration efficiency when directly exposed to a controlled amount of welding fumes for a short-term period. The welding processes studied were restricted to shielded metal arc welding (SMAW), flux cored arc welding (FCAW), gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) processes. Contrary to the SMAW and FCAW processes, the GTAW (or TIG) and the GMAW (or MIG) welding processes do not require the use of flux as part of the overall process. Credit was taken for these processes occurring in inert gas environments and producing minimal amount of smoke. It was concluded that a study involving the SMAW process would also envelop the effects of the TIG and MIG welding processes. The quantity of welding fumes generated during the arc welding process is a function of the particular process, the size and type of electrode, welding machine amperage, and operator proficiency. For this study, the amount of welding for specific testing was equated to the amount of welding normally conducted during plant unit outages. Different welding electrodes were also evaluated, and the subsequent testing was limited to an E7018 electrode which was judged to be representative of all carbon and stainless steel electrodes commonly used at the site. The effect of welding fumes on activated charcoal was tested using a filtration unit complete with prefilters, upstream and downstream high efficiency particulate air (HEPA) filters, and a carbon adsorber section. The complete system was field tested in accordance with ANSI N510 standards prior to exposing the filters and the adsorber bed to welding fumes. The carbon samples were tested at an established laboratory using ASTM D3803-1989 standards.

  7. Airborne nanoparticle exposures associated with the manual handling of nanoalumina and nanosilver in fume hoods

    International Nuclear Information System (INIS)

    Tsai, Su-Jung; Ada, Earl; Isaacs, Jacqueline A.; Ellenbecker, Michael J.

    2009-01-01

    Manual handling of nanoparticles is a fundamental task of most nanomaterial research; such handling may expose workers to ultrafine or nanoparticles. Recent studies confirm that exposures to ultrafine or nanoparticles produce adverse inflammatory responses in rodent lungs and such particles may translocate to other areas of the body, including the brain. An important method for protecting workers handling nanoparticles from exposure to airborne nanoparticles is the laboratory fume hood. Such hoods rely on the proper face velocity for optimum performance. In addition, several other hood design and operating factors can affect worker exposure. Handling experiments were performed to measure airborne particle concentration while handling nanoparticles in three fume hoods located in different buildings under a range of operating conditions. Nanoalumina and nanosilver were selected to perform handling experiments in the fume hoods. Air samples were also collected on polycarbonate membrane filters and particles were characterized by scanning electron microscopy. Handling tasks included transferring particles from beaker to beaker by spatula and by pouring. Measurement locations were the room background, the researcher's breathing zone and upstream and downstream from the handling location. Variable factors studied included hood design, transfer method, face velocity/sash location and material types. Airborne particle concentrations measured at breathing zone locations were analyzed to characterize exposure level. Statistics were used to test the correlation between data. The test results found that the handling of dry powders consisting of nano-sized particles inside laboratory fume hoods can result in a significant release of airborne nanoparticles from the fume hood into the laboratory environment and the researcher's breathing zone. Many variables were found to affect the extent of particle release including hood design, hood operation (sash height, face velocity

  8. Stabilization of heavy metals in MSWI fly ash using silica fume.

    Science.gov (United States)

    Li, Xinying; Chen, Quanyuan; Zhou, Yasu; Tyrer, Mark; Yu, Yang

    2014-12-01

    The objective of this work was to investigate the feasibility and effectiveness of silica fume on stabilizing heavy metals in municipal solid waste incineration (MSWI) fly ash. In addition to compressive strength measurements, hydrated pastes were characterized by X-ray diffraction (XRD), thermal-analyses (DTA/TG), and MAS NMR ((27)Al and (29)Si) techniques. It was found that silica fume additions could effectively reduce the leaching of toxic heavy metals. At the addition of 20% silica fume, leaching concentrations for Cu, Pb and Zn of the hydrated paste cured for 7 days decreased from 0.32 mg/L to 0.05 mg/L, 40.99 mg/L to 4.40 mg/L, and 6.96 mg/L to 0.21 mg/L compared with the MSWI fly ash. After curing for 135 days, Cd and Pb in the leachates were not detected, while Cu and Zn concentrations decreased to 0.02 mg/L and 0.03 mg/L. The speciation of Pb and Cd by the modified version of the European Community Bureau of Reference (BCR) extractions showed that these metals converted into more stable state in hydrated pastes of MSWI fly ash in the presence of silica fume. Although exchangeable and weak-acid soluble fractions of Cu and Zn increased with hydration time, silica fume addition of 10% can satisfy the requirement of detoxification for heavy metals investigated in terms of the identification standard of hazardous waste of China. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Total Fume and Metal Concentrations during Welding in Selected Factories in Jeddah, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mohammad Khalid Goknil

    2010-07-01

    Full Text Available Welding is a major industrial process used for joining metals. Occupational exposure to welding fumes is a serious occupational health problem all over the world. The degree of risk to welder’s health from fumes depends on composition, concentration, and the length of exposure. The aim of this study was to investigate workers’ welding fume exposure levels in some industries in Jeddah, Saudi Arabia. In each factory, the air in the breathing zone within 0.5 m from welders was sampled during 8-hour shifts. Total particulates, manganese, copper, and molybdenum concentrations of welding fumes were determined. Mean values of eight-hour average particulate concentrations measured during welding at the welders breathing zone were 6.3 mg/m3 (Factory 1, 5.3 mg/m3 (Factory 2, 11.3 mg/m3 (Factory 3, 6.8 mg/m3 (Factory 4, 4.7 mg/m3 (Factory 5, and 3.0 mg/m3 (Factory 6. Mean values of airborne manganese, copper, and molybdenum levels measured during welding were in the range of 0.010 mg/m3–0.477 mg/m3, 0.001 mg/m3–0.080 mg/m3 and 0.001 mg/m3–0.058 mg/m3 respectively. Mean values of calculated equivalent exposure values were: 1.50 (Factory 1, 1.56 (Factory 2, 5.14 (Factory 3, 2.21 (Factory 4, 2.89 (Factory 5, and 1.20 (Factory 6. The welders in factories 1, 2, 3, and 4 were exposed to welding fume concentration above the SASO limit value, which may increase the risk of respiratory health problems.

  10. Total fume and metal concentrations during welding in selected factories in Jeddah, Saudi Arabia.

    Science.gov (United States)

    Balkhyour, Mansour Ahmed; Goknil, Mohammad Khalid

    2010-07-01

    Welding is a major industrial process used for joining metals. Occupational exposure to welding fumes is a serious occupational health problem all over the world. The degree of risk to welder's health from fumes depends on composition, concentration, and the length of exposure. The aim of this study was to investigate workers' welding fume exposure levels in some industries in Jeddah, Saudi Arabia. In each factory, the air in the breathing zone within 0.5 m from welders was sampled during 8-hour shifts. Total particulates, manganese, copper, and molybdenum concentrations of welding fumes were determined. Mean values of eight-hour average particulate concentrations measured during welding at the welders breathing zone were 6.3 mg/m(3) (Factory 1), 5.3 mg/m(3) (Factory 2), 11.3 mg/m(3) (Factory 3), 6.8 mg/m(3) (Factory 4), 4.7 mg/m(3) (Factory 5), and 3.0 mg/m(3) (Factory 6). Mean values of airborne manganese, copper, and molybdenum levels measured during welding were in the range of 0.010 mg/m(3)-0.477 mg/m(3), 0.001 mg/m(3)-0.080 mg/m(3) and 0.001 mg/m(3)-0.058 mg/m(3) respectively. Mean values of calculated equivalent exposure values were: 1.50 (Factory 1), 1.56 (Factory 2), 5.14 (Factory 3), 2.21 (Factory 4), 2.89 (Factory 5), and 1.20 (Factory 6). The welders in factories 1, 2, 3, and 4 were exposed to welding fume concentration above the SASO limit value, which may increase the risk of respiratory health problems.

  11. Global metabolomic profiling reveals an association of metal fume exposure and plasma unsaturated fatty acids.

    Directory of Open Access Journals (Sweden)

    Yongyue Wei

    Full Text Available Welding-associated air pollutants negatively affect the health of exposed workers; however, their molecular mechanisms in causing disease remain largely unclear. Few studies have systematically investigated the systemic toxic effects of welding fumes on humans.To explore the effects of welding fumes on the plasma metabolome, and to identify biomarkers for risk assessment of welding fume exposure.The two-stage, self-controlled exploratory study included 11 boilermakers from a 2011 discovery panel and 8 boilermakers from a 2012 validation panel. Plasma samples were collected pre- and post-welding fume exposure and analyzed by chromatography/mass spectrometry.Eicosapentaenoic or docosapentaenoic acid metabolic changes post-welding were significantly associated with particulate (PM2.5 exposure (p<0.05. The combined analysis by linear mixed-effects model showed that exposure was associated with a statistically significant decline in metabolite change of eicosapentaenoic acid [β(95% CI = -0.013(-0.022 ≈ -0.004; p = 0.005], docosapentaenoic acid n3 [β(95% CI = -0.010(-0.018 ≈ -0.002; p = 0.017], and docosapentaenoic acid n6 [β(95% CI = -0.007(-0.013 ≈ -0.001; p = 0.021]. Pathway analysis identified an association of the unsaturated fatty acid pathway with exposure (p Study-2011 = 0.025; p Study-2012 = 0.021; p Combined = 0.009. The functional network built by these fatty acids and their interactive genes contained significant enrichment of genes associated with various diseases, including neoplasms, cardiovascular diseases, and lipid metabolism disorders.High-dose exposure of metal welding fumes decreases unsaturated fatty acids with an exposure-response relationship. This alteration in fatty acids is a potential biological mediator and biomarker for exposure-related health disorders.

  12. Characterization of Tungsten Inert Gas (TIG) Welding Fume Generated by Apprentice Welders.

    Science.gov (United States)

    Graczyk, Halshka; Lewinski, Nastassja; Zhao, Jiayuan; Concha-Lozano, Nicolas; Riediker, Michael

    2016-03-01

    Tungsten inert gas welding (TIG) represents one of the most widely used metal joining processes in industry. Its propensity to generate a greater portion of welding fume particles at the nanoscale poses a potential occupational health hazard for workers. However, current literature lacks comprehensive characterization of TIG welding fume particles. Even less is known about welding fumes generated by welding apprentices with little experience in welding. We characterized TIG welding fume generated by apprentice welders (N = 20) in a ventilated exposure cabin. Exposure assessment was conducted for each apprentice welder at the breathing zone (BZ) inside of the welding helmet and at a near-field (NF) location, 60cm away from the welding task. We characterized particulate matter (PM4), particle number concentration and particle size, particle morphology, chemical composition, reactive oxygen species (ROS) production potential, and gaseous components. The mean particle number concentration at the BZ was 1.69E+06 particles cm(-3), with a mean geometric mean diameter of 45nm. On average across all subjects, 92% of the particle counts at the BZ were below 100nm. We observed elevated concentrations of tungsten, which was most likely due to electrode consumption. Mean ROS production potential of TIG welding fumes at the BZ exceeded average concentrations previously found in traffic-polluted air. Furthermore, ROS production potential was significantly higher for apprentices that burned their metal during their welding task. We recommend that future exposure assessments take into consideration welding performance as a potential exposure modifier for apprentice welders or welders with minimal training. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  13. Induction of Plac8 promotes pro-survival function of autophagy in cadmium-induced prostate carcinogenesis.

    Science.gov (United States)

    Kolluru, Venkatesh; Pal, Deeksha; Papu John, A M Sashi; Ankem, Murali K; Freedman, Jonathan H; Damodaran, Chendil

    2017-11-01

    Chronic exposure to cadmium is known to be a risk factor for human prostate cancer. Despite over-whelming evidence of cadmium causing carcinogenicity in humans, the specific underlying molecular mechanisms that govern metal-induced cellular transformation remain unclear. Acute exposure (up to 72 h) to cadmium induces apoptosis in normal prostate epithelial cells (RWPE-1), while chronic exposure (>1 year) transforms these cells to a malignant phenotype (cadmium-transformed prostate epithelial cells; CTPE). Increased expression of autophagy-regulated genes; Plac8, LC3B and Lamp-1; in CTPE cells was associated with cadmium-induced transformation. Increased expression of Plac8, a regulator of autophagosome/autolysosome fusion, facilitates the pro-survival function of autophagy and upregulation of pAKT (ser473) and NF-κβ, to allow CTPE to proliferate. Likewise, inhibition of Plac8 suppresses CTPE cell growth. Additionally, overexpression of Plac8 in RWPE-1 cells induces resistance to cadmium toxicity. Pharmacological inhibitors and an inducer of autophagy failed to affect Plac8 expression and CTPE cell viability, suggesting a unique role for Plac8 in cadmium-induced prostate epithelial cell transformation. These results support a role for Plac8 as an essential component in the cadmium-induced transformation of normal prostate epithelial cells to a cancerous state. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Characterization of Stainless Steel Welding Fume Particles : Influence of Stainless Steel Grade, Welding Parameters and Particle Size

    OpenAIRE

    Mei, Nanxuan

    2016-01-01

    Welding is a widely used method to join two pieces of stainless steel. Since it produces a large amount of fume during the process, it can cause adverse health effects. The welding fume particles contain many elements. Among them Cr, Mn and Ni are of concern. These three elements can cause diseases if inhaled by humans, especially Cr(VI). In this project, welding fume particles are collected during welding of different stainless steel grades (austenitic AISI 304L and duplex LDX2101). Furtherm...

  15. Single and Combined Exposure to Zinc- and Copper-Containing Welding Fumes Lead to Asymptomatic Systemic Inflammation.

    Science.gov (United States)

    Markert, Agnieszka; Baumann, Ralf; Gerhards, Benjamin; Gube, Monika; Kossack, Veronika; Kraus, Thomas; Brand, Peter

    2016-02-01

    Recently, it has been shown that exposure to welding fumes containing both zinc and copper leads to asymptomatic systemic inflammation in humans as shown by an increase of blood C-reactive protein. In the present study, it was investigated which metal is responsible for this effect. Fifteen healthy male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc. For each exposure blood C-reactive protein increased. Copper- and zinc-containing welding fumes are able to induce systemic inflammation.

  16. Cadmium uptake by plants

    Energy Technology Data Exchange (ETDEWEB)

    Haghiri, F.

    1973-01-01

    Absorption of /sup 115m/Cd by soybean (Gylcine max l.) plants via foliar and root systems and translocation into the seed was determined. The uptake of /sup 115m/Cd by soybeans via the root system was more efficient than that of the foliar placement. Growth and Cd concentrations of soybean and wheat (Triticum aestivum l.) tops were influenced by soil-applied Cd. In both crops, the Cd concentration of plant tops increased while yield decreased with increasing levels of applied Cd. Cadmium toxicitiy began to occur in both crops at the lowest level of soil applied Cd (2.5 ppM). With soybean plants, Cd toxicity symptoms resembled fe chlorosis. For wheat plants there were no visual symptoms other than the studied growth. The relative concentration of Cd found in several vegetable crops varied depending on the plant species. The relative Cd concentration in descending order for various vegetables was lettuce (Lactuca sativa l.) > radish top (Raphanus sativus l.) > celery stalk (Apium graveolens l.) > celery leaves greater than or equal to green pepper (Capsicum frutescens l.) > radish roots.

  17. antioxidants, cadmium-induced toxicity, serum biochemical

    African Journals Online (AJOL)

    Daniel Owu

    histopathological parameters of the liver, kidney and testes of the Wister rate were investigated. Cadmium (CD) in the dose range ... and their mechanisms of actions. Key words: vitamin C, cadmium, kidney, testes, hormones, antioxidants ... Cancer (Jarup et al 1998; Kjellstrom 1992;. Waalkes et al 1999), Cadmium has also ...

  18. Bioavailability of cadmium from linseed and cocoa

    DEFF Research Database (Denmark)

    Hansen, Max; Sloth, Jens Jørgen; Rasmussen, Rie Romme

    In Denmark and EU the exposure of cadmium from food is at a level that is relatively close to the Tolerable Daily Intake (TDI). This report describes an investigation of the bioavailability of cadmium in selected food items known to contain high levels of cadmium. The purpose was to provide data ...... or crushed linseed nor the intake of cocoa and chocolate....

  19. 29 CFR 1928.1027 - Cadmium.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Cadmium. 1928.1027 Section 1928.1027 Labor Regulations...) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR AGRICULTURE Occupational Health § 1928.1027 Cadmium. See § 1910.1027, Cadmium. [61 FR 9255, Mar. 7, 1996] ...

  20. Hsp27, Hsp70, and metallothionein in MDCK and LLC-PK1 renal epithelial cells: effects of prolonged exposure to cadmium

    International Nuclear Information System (INIS)

    Bonham, Rita T.; Fine, Michael R.; Pollock, Fiona M.; Shelden, Eric A.

    2003-01-01

    Cadmium is a widely distributed industrial and environmental toxin. The principal target organ of chronic sublethal cadmium exposure is the kidney. In renal epithelial cells, acute high-dose cadmium exposure induces differential expression of proteins, including heat shock proteins. However, few studies have examined heat shock protein expression in cells after prolonged exposure to cadmium at sublethal concentrations. Here, we assayed total cell protein, neutral red uptake, cell death, and levels of metallothionein and heat shock proteins Hsp27 and inducible Hsp70 in cultures of MDCK and LLC-PK1 renal epithelial cells treated with cadmium for 3 days. Treatment with cadmium at concentrations equal to or greater than 10 μM (LLC-PK1) or 25 μM (MDCK) reduced measures of cell vitality and induced cell death. However, a concentration-dependent increase in Hsp27 was detected in both cell types treated with as little as 5 μM cadmium. Accumulation of Hsp70 was correlated only with cadmium treatment at concentrations also causing cell death. Metallothionein was maximally detected in cells treated with cadmium at concentrations that did not reduce cell vitality, and further increases were not detected at greater concentrations. These results reveal that heat shock proteins accumulate in renal epithelial cells during prolonged cadmium exposure, that cadmium induces differential expression of heat shock protein in epithelial cells, and that protein expression patterns in epithelial cells are specific to the cadmium concentration and degree of cellular injury. A potential role for Hsp27 in the cellular response to sublethal cadmium-induced injury is also implicated by our results

  1. Coprecipitation of cadmium with calcite

    International Nuclear Information System (INIS)

    Fujino, Osamu; Kumagai, Tetsu; Shigematsu, Tsunenobu; Matsui, Masakazu

    1976-01-01

    The distribution of cadmium between precipitates of calcite and saturated aqueous solution was measured at 25 0 C to understand the distribution of cadmium in the bivalves. Calcite was precipitated from calcium bicarbonate solution by the gradual release of carbon dioxide. The cadmium ions were coprecipitated in calcite, obeying the logarithmic distribution law. The apparent distribution coefficient was decreased as α, α'-dipyridyl increased, but the true distribution coefficient was found to be an almost constant value, 560. This value is fairly close to the ratio of solubility product constants K sub(calcite)/K sub(CdCO 3 ), 890. This suggests that the deviation of the present solid solution from ideality is not very large. (auth.)

  2. Electron transfer of monovalent cadmium

    International Nuclear Information System (INIS)

    Lerat-Parizot, O.; Potier, J.; Hickel, B.

    1993-01-01

    The surveys presented here concern monovalent Cadmium in aqueous solutions, produced by reduction of Cd(II), using pulsed radiolysis. We specifically studied the Cd(I) reactivity when complexed in certain synthetic ionophores. Cd(I), being an extremely powerful reducing agent, regains its stable valence by transferring an electron to an acceptor. Organic molecules are introduced into a solvent, permitting the analysis of the transfer rate of this electron. We investigated the influence of the ligand specificities and the variation of the electron transfer rate, that depend on the potential difference between Cadmium and the acceptor being used. 34 refs

  3. The Study Of Histopathological Effects Of Welding Fumes On Spermatogenesis In Rat

    Directory of Open Access Journals (Sweden)

    Arab M R

    2005-07-01

    Full Text Available Background: Fumes generated during electric welding are one of air pollutants of working place in industrial companies, which can cause some clinical signs and diseases in worker, including mucosal irritation, changing of semen quality and cancer. Chronic exposure of workers with these fumes can cause reduce sperm motility and forward penetration and decrease in normal sperm count. Although a lot of researches were done in this field up to now, there is little information about histopathological effects of these fumes on germinal epithelium. The aim of this study was to identify structural changes of germinal epithelium in Rat as an experimental model after exposure to fumes of electric welding in exposure chamber. Material and Methods: A total number of 60 Sprague Dawley Rats were chosen and divided into experimental (40 and control (20 groups. Each of groups was subdivided into 2, 4, 6 and 8-week subgroups. The number of Rat in each subgroup of experimental and control group was 10 and 5 respectively. Animals were housed in standard situation. After adaptation experimental group were exposed to fumes of electric welding (AMA 2000 electrode, 100 Ampere, 0.1 cm/s speed of electrode welding for 2 hour/day and 5 day/week. The rate of air turn over in exposure chamber was fixed to 12-15/hour. The amount of O3, CO, CO2, NO + NO2 and particulate matter were measured by Galtec detectors and Cellulose acetate filter respectively. According to time table animals were killed and specimens from testis were taken and fixed in formaline buffer solution and processed routinely. Sections with 5-7 micrometer in thickness were stained by H-E, PAS, PNA and Alcian blue pH=2.5. The thickness of germinal epithelium was measured and data were analyzed by Kruskall Wallis test. Results: The results of this study showed a few quantitative and qualitative changes in germinal epithelium. Vasodilatation of vessels in tunica albuginea and interstitial tissue, decreasing of

  4. The comparative assessment of welders’ exposure to welding fumes based on mass and number concentration

    Directory of Open Access Journals (Sweden)

    Javad Sajedifar

    2016-12-01

    Full Text Available Introduction: Nowadays, Shielded Metal Arc Welding (SMAW is the most widely used arc welding. During the welding operation, typically, various harmful agents such as fumes, gases, heat, sound and ultraviolet radiation are produced of which fume is the most important component from the viewpoint of occupational health. The present study aims to compare the number and the mass concentration emitted in SMAW to determine the most appropriate index of exposure to fumes in the welding processes. Material and Method: In this study, the portable laser aerosol spectrometer and dust monitor of GRIMM, model 1.106, was used to measure the number and mass concentration of fumes emitted from SMAW on 304 stainless steel with a thickness of 0.4 mm. Air sampling was performed at a distance of 41 cm representing the welder’s breathing zone. The measurements of number concentration (NC and mass concentration (MC were taken under the condition of 25 volt voltage and direct current of the electrode polarity. Result: The total NC and MC of welding fumes in welder’s breathing zone was 1140451 particles per liter and 1631.11 micrograms per cubic meter, respectively. The highest number concentration was found to correspond to the particles with 0.35 to 0.5 micrometer-sized distribution (NC1; 938976 particles per liter and the lowest was related to the particles with 5 to 6.5 micrometer-sized distribution (NC7; 288 particles per liter and the particles larger than 6.5 micrometer (NC8; 463 particles per liter. Moreover, the highest mass concentration was related to the particles with 0.35 to 0.5 micrometer-sized distribution (MC1; 450 micrograms per cubic meter and the particles larger than 6.5 micrometer (MC8; 355 micrograms per cubic meter. Conclusion: The findings indicated that there is no agreement between number and mass concentration as two particles assessment index, and as the particles’ size become smaller, the mismatch of them is becoming more apparent

  5. Effect of stainless steel manual metal arc welding fume on free radical production, DNA damage, and apoptosis induction.

    Science.gov (United States)

    Antonini, James M; Leonard, Stephen S; Roberts, Jenny R; Solano-Lopez, Claudia; Young, Shih-Houng; Shi, Xianglin; Taylor, Michael D

    2005-11-01

    Questions exist concerning the potential carcinogenic effects after welding fume exposure. Welding processes that use stainless steel (SS) materials can produce fumes that may contain metals (e.g., Cr, Ni) known to be carcinogenic to humans. The objective was to determine the effect of in vitro and in vivo welding fume treatment on free radical generation, DNA damage, cytotoxicity and apoptosis induction, all factors possibly involved with the pathogenesis of lung cancer. SS welding fume was collected during manual metal arc welding (MMA). Elemental analysis indicated that the MMA-SS sample was highly soluble in water, and a majority (87%) of the soluble metal was Cr. Using electron spin resonance (ESR), the SS welding fume had the ability to produce the biologically reactive hydroxyl radical (*OH), likely as a result of the reduction of Cr(VI) to Cr(V). In vitro treatment with the MMA-SS sample caused a concentration-dependent increase in DNA damage and lung macrophage death. In addition, a time-dependent increase in the number of apoptotic cells in lung tissue was observed after in vivo treatment with the welding fume. In summary, a soluble MMA-SS welding fume was found to generate reactive oxygen species and cause DNA damage, lung macrophage cytotoxicity and in vivo lung cell apoptosis. These responses have been shown to be involved in various toxicological and carcinogenic processes. The effects observed appear to be related to the soluble component of the MMA-SS sample that is predominately Cr. A more comprehensive in vivo animal study is ongoing in the laboratory that is continuing these experiments to try to elucidate the potential mechanisms that may be involved with welding fume-induced lung disease.

  6. Histological Study of Toxic Effects of Solder Fumes on Thickness of Germinal Epithelium in Seminiferous Tubule in Rat

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab

    2014-10-01

    Full Text Available Background: Toxic fumes generating during soldering contains various contaminants. The aim of the study was to determine toxic effects of solder fumes in thickness of semniferous tubule in Rat. Materials and Methods 48 male adult rats were randomly divided into experimental (n=30 and control (n=18 groups. Based on exposure time, each group was further divided into three subgroups such as 2, 4 and 6 weeks. The concentrations of toxic fumes were measured by standard method. Rats of experimental group were exposed to solder fumes for 1 hour/day. According to time table rats of experimental and control subgroups were killed. After fixation of testis, paraffin sections were stained by Hematoxylin & Eosin. The thicknesses of germinal epithelium were measured and data were analyzed by SPSS software version 17 with Mann Whitney test. Results: The results showed that the concentration of fumes was 0.193 mg/m3 for formaldehyde, 0.35 mg/m3 for Stanum (Sn and 3 mg/m3 for Pb. Although there was no significant difference for weight of rats’ testis between control and experimental subgroups, there was only a significant difference for the thickness of germinal epithelium between 6 week experimental and control subgroups ( p<0.02. Conclusion: The results of study showed that solder fumes can change the structure and thickness of seminiferous epithelium in experimental groups in a time dependent manner.

  7. Influence of cadmium on ketamine-induced anesthesia and brain microsomal Na[sup +], K[sup +]-ATPase in mice

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Y.; Sangiah, S. (Oklahoma State Univ., Stillwater, OK (United States))

    1994-10-01

    Cadmium is a rare metallic element, present in almost all types of food. Shellfish, wheat and rice accumulate very high amounts. Occupational and environmental pollutants are the main sources of cadmium exposure. Cadmium has a very long biologic half-life. Exposure to Cadmium causes anemia, hypertension, hepatic, renal, pulmonary and cardiovascular disorders as well as being a possible mutagen, teratogen and carcinogen. Acute cadmium treatment increased the hexobarbital sleeping time and inhibited hepatic microsomal drug metabolism due to a decrease in cytochrome P[sub 450] content. Cadmium potentiated ethanol-induced sleep in a dose-dependent manner. Cadmium has been shown to inhibit brain microsomal Na[sup +], K[sup +]-ATPase activity in vitro and in vivo. Cadmium and ethanol additively inhibited brain Na[sup +], K[sup +]-ATPase. This might be a direct interaction between cadmium and ethanol in the central nervous system. Ketamine is an intravenous anesthetic agent. It acts on central nervous system and produces [open quotes]dissociative anaesthesia.[close quotes] Ketamine provides adequate surgical anesthesia and is used alone in humans and/or combination with xylazine, an [alpha][sub 2]-adrenergic agonist in animals. It produces CNS depression, analgesia, amnesia, immobility and a feeling of dissociation from the environment. Ketamine is a non-competitive antagonist of the NMDA subset of the glutamate receptor. This perhaps results in an increase in neuronal activity leading to disorganization of normal neurotransmission and produces dissociative anesthetic state. Because it is different from most other anesthetics, ketamine may be expected to have a unique effect on brain biochemical parameters and enzymes. The purpose of this study was to examine the interactions between cadmium and ketamine on the central nervous system and ATPase, in an attempt to further understand the mechanism of action. 12 refs., 3 figs.

  8. [Investigation of urinary cadmium reference of general population in two rural high background areas of soil cadmium and non-cadmium-polluted in China].

    Science.gov (United States)

    Han, Jingxiu; Li, Qiujuan; Yao, Dancheng; Zheng, Jiangang; Zhang, Wenli; Shang, Qi

    2014-09-01

    To study the reference of urinary. cadmium of the general population in rural high background areas of soil cadmium and non-cadmium contaminated in China. In rural high background areas of soil cadmium and non-cadmium contaminated, randomly selected non-occupational-cadmium exposed population 1134 people (male 519, female 615) with each gender and age groups, questionnaire surveyed and collected random urine. Urinary cadmium and urinary creatinine (Cr) concentration were tested, excluding urinary Cr 3 g/L. Analyze the impact factors of urinary cadmium and calculated 95% quantile (P,95 ) of urinary cadmium after correction by urinary Cr. Female median urinary cadmium was significantly higher than men, male smokers median urinary cadmium was significantly higher than male non-smokers (P 30 year-old. According to gender, and 15 -30, 30 years old, analysis the upper limit of cadmium in urine. The 95% upper limit of urinary cadmium of 30 year-old female (12.24 microg/gCr) was significantly higher than other populations ( population exceeded the upper limit (5 microg/gCr) of the occupational cadmium poisoning diagnostic criteria in China (GBZ 17-2002). In the two rural high background areas of soil cadmium and non-cadmium polluted , urinary cadmium reference of non-cadmium-occupational-exposed male is <9.0 microg/gCr, and female <13.0 microg/gCr.

  9. Chloride accelerated test: influence of silica fume, water/binder ratio and concrete cover thickness

    Directory of Open Access Journals (Sweden)

    E. Pereira

    Full Text Available In developed countries like the UK, France, Italy and Germany, it is estimated that spending on maintenance and repair is practically the same as investment in new constructions. Therefore, this paper aims to study different ways of interfering in the corrosion kinetic using an accelerated corrosion test - CAIM, that simulates the chloride attack. The three variables are: concrete cover thickness, use of silica fume and the water/binder ratio. It was found, by analysis of variance of the weight loss of the steel bars and chloride content in the concrete cover thickness, there is significant influence of the three variables. Also, the results indicate that the addition of silica fume is the path to improve the corrosion protection of low water/binder ratio concretes (like 0.4 and elevation of the concrete cover thickness is the most effective solution to increase protection of high water/binder ratio concrete (above 0.5.

  10. Non-occupational exposure to paint fumes during pregnancy and fetal growth in a general population

    DEFF Research Database (Denmark)

    Sørensen, Mette; Andersen, Anne-Marie N; Raaschou-Nielsen, Ole

    2010-01-01

    Occupational exposure to organic solvents during pregnancy has been associated with reduced fetal growth. Though organic solvents in the form of paint fumes are also found in the home environment, no studies have investigated the effect of such exposure in a general population. We studied...... associations between residential exposure to paint fumes during pregnancy and fetal growth within the Danish National Birth Cohort which consecutively recruited pregnant women from 1996 to 2002 from all over Denmark. Around the 30th pregnancy week, 19,000 mothers were interviewed about use of paint...... in their residence during pregnancy. The mothers were also asked about smoking habits and alcohol consumption during pregnancy, pre-pregnancy weight, height, parity and occupation. Information on birth weight and gestational age was obtained from national registers. We found that 45% of the mothers had been exposed...

  11. Controversial effects of fumed silica on the curing and thermomechanical properties of epoxy composites

    Directory of Open Access Journals (Sweden)

    2010-06-01

    Full Text Available The effect of fumed silica on the curing of a trimethylolpropane epoxy resin was investigated by thermal analysis methods like Differential Scanning Calorimetry (DSC, and Dynamic Mechanical Analysis (DMA. The fumed silica used here is a by-product of the silicon and ferrosilicon industry, consisting of micro and nanosized particles. Both the curing reaction and the properties of the obtained composites were affected by the filler content. Different trends were observed for filler contents above and below the 30 wt%. Up to 30 wt%, the behaviour can be explained as a predominantly agglomeration effect. For 30 wt% and higher filler contents, single particles seem to play a more important role.

  12. Mass spectrometric investigation of synthetic glycoside of muramyl dipeptide immobilized on fumed silica surface

    International Nuclear Information System (INIS)

    Kulik, Tetiana V.; Azizova, Liana R.; Palyanytsya, Borys B.; Zemlyakov, Alexander E.; Tsikalova, Victoria N.

    2010-01-01

    N-Acetylmuramyl-L-alanyl-D-isoglutamine or muramyl dipeptide is a cleavage product of peptidoglycan by lysozyme. This study explored the use of the temperature-programmed desorption mass spectrometry (TPDMS) in analysis of glycoside of muramyl dipeptide: O-{(4-tert-butylcyclohexyl)-2-acetamido-2, 3-dideoxy-β-D-glucopyranoside-3-yl}-D-lactoyl-L-alanyl-D-isoglutamine (MDP) on the surface of fumed silica. Stages of pyrolysis of MDP in condensed state and on the silica surface have been determined. Three stages have been clear identified under pyrolysis of MDP on the silica surface. Kinetic parameters of thermal reactions on the fumed silica surface and in the condensed state have been calculated.

  13. Upgrading offshore pipelines concrete coated by silica fume additive against aggressive mechanical laying

    Directory of Open Access Journals (Sweden)

    M.I. Abdou

    2016-06-01

    Full Text Available Studies have been carried out to investigate the possibility of utilizing a broad range of micro-silica partial additions with cement in the production of concrete coating. This study investigated the strength properties and permeability of micro-silica concrete to achieve resistance toward concrete cracking and damage during laying. The chemical composition of micro-silica (silica fume was determined, and has been conducted on concrete mixes with additions of 3 up to 25% by weight of cement in concrete. Properties of hardened concrete such as compressive strength, flexural strength, and permeability have been assessed and analyzed. Cubic specimens and beams were produced and cured in a curing tank for 7 and 28 days. Testing results have shown that additions of silica fume to cement between 5% and 7%, which acts as a filler and cementations material, developed high flexural and compressive strength with reduction of permeability.

  14. Silica Fume and Fly Ash Admixed Can Help to Improve the PRC Durability Combine Microscopic Analysis

    Directory of Open Access Journals (Sweden)

    Xiao Li-guang

    2016-01-01

    Full Text Available Silica fume/Fly ash RPC can greatly improve durability. When Silica fume to replace the same amount of 8% of the proportion of cement, re-mixed 15min of mechanically activated Fly ash content of 10%, by chloride ion flux detector measuring, complex doped than the reference RPC impermeability improved significantly; In addition, by using static nitrogen adsorption method showed, RPC internal pore structure determination, the hole integral volume was lower than the reference admixed RPC integral pore volume significantly; And combined SEM microscopic experimental methods, mixed of RPC internal structure and the formation mechanism analysis showed that, SF/FA complex fully embodies the synergy doped composites “Synergistic” principle.

  15. Aerosol characterization and pulmonary responses in rats after short-term inhalation of fumes generated during resistance spot welding of galvanized steel

    Directory of Open Access Journals (Sweden)

    James M. Antonini

    Full Text Available Resistance spot welding is a common process to join metals in the automotive industry. Adhesives are often used as sealers to seams of metals that are joined. Anti-spatter compounds sometimes are sprayed onto metals to be welded to improve the weldability. Spot welding produces complex aerosols composed of metal and volatile compounds (VOCs which can cause lung disease in workers. Male Sprague-Dawley rats (n = 12/treatment group were exposed by inhalation to 25 mg/m3 of aerosol for 4 h/day × 8 days during spot welding of galvanized zinc (Zn-coated steel in the presence or absence of a glue or anti-spatter spray. Controls were exposed to filtered air. Particle size distribution and chemical composition of the generated aerosol were determined. At 1 and 7 days after exposure, bronchoalveolar lavage (BAL was performed to assess lung toxicity. The generated particles mostly were in the submicron size range with a significant number of nanometer-sized particles formed. The primary metals present in the fumes were Fe (72.5% and Zn (26.3%. The addition of the anti-spatter spray and glue did affect particle size distribution when spot welding galvanized steel, whereas they had no effect on metal composition. Multiple VOCs (e.g., methyl methacrylate, acetaldehyde, ethanol, acetone, benzene, xylene were identified when spot welding using either the glue or the anti-spatter spray that were not present when welding alone. Markers of lung injury (BAL lactate dehydrogenase and inflammation (total BAL cells/neutrophils and cytokines/chemokines were significantly elevated compared to controls 1 day after exposure to the spot welding fumes. The elevated pulmonary response was transient as lung toxicity mostly returned to control values by 7 days. The VOCs or the concentrations that they were generated during the animal exposures had no measurable effect on the pulmonary responses. Inhalation of galvanized spot welding fumes caused acute lung toxicity

  16. Characteristics of PAHs from deep-frying and frying cooking fumes.

    Science.gov (United States)

    Yao, Zhiliang; Li, Jing; Wu, Bobo; Hao, Xuewei; Yin, Yong; Jiang, Xi

    2015-10-01

    Cooking fumes are an important indoor source of polycyclic aromatic hydrocarbons (PAHs). Because indoor pollution has a more substantial impact on human health than outdoor pollution, PAHs from cooking fumes have drawn considerable attention. In this study, 16 PAHs emitted through deep-frying and frying methods using rapeseed, soybean, peanut, and olive oil were examined under a laboratory fume hood. Controlled experiments were conducted to collect gas- and particulate-phase PAHs emitted from the cooking oil fumes, and PAH concentrations were quantified via high-performance liquid chromatography (HPLC). The results show that deep-frying methods generate more PAHs and benzo[a]pyrene (B[a]P) (1.3 and 10.9 times, respectively) because they consume greater volumes of edible oil and involve higher oil temperatures relative to those of frying methods. In addition, the total B[a]Peq concentration of deep-frying is 2.2-fold larger than that of frying. Regarding the four types of edible oils studied, rapeseed oil produced more PAH emission than the other three oil varieties. For all of the cooking tests, three- and four-ringed PAHs were the main PAH components regardless of the food and oil used. Concerning the PAH partition between gas and particulate phase, the gaseous compounds accounted for 59-96 % of the total. Meanwhile, the particulate fraction was richer of high molecular weight PAHs (five-six rings). Deep-frying and frying were confirmed as important sources of PAH pollution in internal environments. The results of this study provide additional insights into the polluting features of PAHs produced via cooking activities in indoor environments.

  17. Influence of silica fume on mechanical and physical properties of recycled aggregate concrete

    OpenAIRE

    Çakır, Özgür; Sofyanlı, Ömer Özkan

    2015-01-01

    Several studies related to sustainable concrete construction have encouraged development of composite binders, involving Portland cement, industrial by-products, and concrete mixes with partial replacement of natural aggregate with recycled aggregate. In this paper, the effects of incorporating silica fume (SF) in the concrete mix design to improve the quality of recycled aggregates in concrete are presented. Portland cement was replaced with SF at 0%, 5% and 10%. Specimens were manufactured ...

  18. In situ polymerization of L-Lactide in the presence of fumed silica

    International Nuclear Information System (INIS)

    Prebe, A.; Alcouffe, P.; Cassagnau, Ph.; Gerard, J.F.

    2010-01-01

    Chemiorheology, i.e. rheological changes during the polymerization, of a biosourced monomer, i.e. L-Lactide, containing fumed silica have been studied. For that purpose, the reaction was proceeded in situ between the plates of a dynamic rheometer. The polymerization kinetics was followed from the variation of the complex shear modulus versus reaction time. Moreover, at temperatures lower than the crystallization temperature, it was possible to follow the crystallization process while the polymerization takes place. Adding fumed silica particles into the monomer leads to the formation of a physical (percolated) network from particle-particle interactions, i.e. silica, in the L-Lactide probably hydrophilic interactions. The gel-like structure was kept while the polymerization as long as the strain remains low indicating that the silica particle network remains weak. Furthermore, the mechanism of the break down of the gel structure under large deformation as well as the recovery was discussed. It seems that the non-linearity effect of the nanocomposites stems in the silica inter-particle interactions. It was found that silica particles do not have any effect on the temperature of crystallization - molar mass relation but could act as nucleating agent. In situ polymerization of L-Lactide in the presence of 5 wt.% of modified fumed silica was carried out in a reactor. It was found that fumed hydrophilic silica leaded to a microcomposite with highly dense agglomerates in the polymer matrix whereas with a less hydrophilic silica it was possible to decrease the size of the agglomerates increasing the dispersion. The finest dispersion state was achieved with the 'initiating' functionalized silica leading to a 'grafting from' polymerization of the L-Lactide. Such functionalized silica leads to a nanoscale dispersion in a one-step bulk polymerization with only a few small agglomerates.

  19. Characterization of the early pulmonary inflammatory response associated with PTFE fume exposure

    Science.gov (United States)

    Johnston, C. J.; Finkelstein, J. N.; Gelein, R.; Baggs, R.; Oberdorster, G.; Clarkson, T. W. (Principal Investigator)

    1996-01-01

    Heating of polytetrafluoroethylene (PTFE) has been described to release fumes containing ultrafine particles (approximately 18 nm diam). These fumes can be highly toxic in the respiratory tract inducing extensive pulmonary edema with hemorrhagic inflammation. Fischer-344 rats were exposed to PTFE fumes generated by temperatures ranging from 450 to 460 degrees C for 15 min at an exposure concentration of 5 x 10(5) particles/cm3, equivalent to approximately 50 micrograms/m3. Responses were examined 4 hr post-treatment when these rats demonstrated 60-85% neutrophils (PMNs) in their lung lavage. Increases in abundance for messages encoding the antioxidants manganese superoxide dismutase and metallothionein (MT) increased 15- and 40-fold, respectively. For messages encoding the pro- and anti-inflammatory cytokines: inducible nitric oxide synthase, interleukin 1 alpha, 1 beta, and 6 (IL-1 alpha, IL-1 beta, and IL-6), macrophage inflammatory protein-2, and tumor necrosis factor-alpha (TNF alpha) increases of 5-, 5-, 10-, 40-, 40-, and 15-fold were present. Vascular endothelial growth factor, which may play a role in the integrity of the endothelial barrier, was decreased to 20% of controls. In situ sections were hybridized with 33P cRNA probes encoding IL-6, MT, surfactant protein C, and TNF alpha. Increased mRNA abundance for MT and IL-6 was expressed around all airways and interstitial regions with MT and IL-6 demonstrating similar spatial distribution. Large numbers of activated PMNs expressed IL-6, MT, and TNF alpha. Additionally, pulmonary macrophages and epithelial cells were actively involved. These observations support the notion that PTFE fumes containing ultrafine particles initiate a severe inflammatory response at low inhaled particle mass concentrations, which is suggestive of an oxidative injury. Furthermore, PMNs may actively regulate the inflammatory process through cytokine and antioxidant expression.

  20. Increased levels of oxidative DNA damage attributable to cooking-oil fumes exposure among cooks.

    Science.gov (United States)

    Ke, Yuebin; Cheng, Jinquan; Zhang, Zhicheng; Zhang, Renli; Zhang, Zhunzhen; Shuai, Zhihong; Wu, Tangchun

    2009-07-01

    Previous investigations have indicated that cooks are exposed to polycyclic aromatic hydrocarbons (PAHs) from cooking-oil fumes. However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene(1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36); all were male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 h prior to sampling was estimated from questionnaires. The urine samples were frozen for later analyses of 8-OHdG and 1-OHP levels by high-performance liquid chromatography. Excretion in urine of 8-OHdG was similar for controls (mean 1.2micromol/mol creatinine, n = 36), and for those who had been in the kitchen with an exhaust-hood operating (mean 1.5micromol/mol creatinine, n = 45). Cooks exposed to cooking-oil fumes without exhaust-hood operation had significantly increased excretion of 8-OHdG (mean 2.3micromol/mol creatinine, n = 18), compared with controls. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. The results indicate that exposure to PAH or possibly other compounds in cooking-oil fumes may cause oxidative DNA damage.

  1. Risk Communication Concerning Welding Fumes for the Primary Preventive Care of Welding Apprentices in Southern Brazil

    OpenAIRE

    Cezar-Vaz, Marta Regina; Bonow, Clarice Alves; Cezar Vaz, Joana

    2015-01-01

    This study’s aim was to assess the perceptions of welding apprentices concerning welding fumes being associated with respiratory and cardiovascular disorders and assess the implementation of risk communication as a primary prevention tool in the welding training process. This quasi-experimental, non-randomized study with before-and-after design was conducted with 84 welding apprentices in Southern Brazil. Poisson Regression analysis was used. Relative Risk was the measure used with a 95% co...

  2. Chelating agents and cadmium toxicity: problems and prospects.

    OpenAIRE

    Nordberg, G F

    1984-01-01

    Symptoms and signs in humans after excessive exposure to cadmium usually involve the gastrointestinal tract after single oral intake, the lung after acute inhalation, and the kidney after long-term exposure. These organs are usually considered to be the "critical" organs, i.e., the organs most sensitive at a certain type of exposure. The type of Cd-related damage that is most common in humans is probably the renal toxicity after long-term exposure. Most animal experiments, including the most ...

  3. Neurobehavioral toxicity of cadmium sulfate to the planarian Dugesia dorotocephala

    Energy Technology Data Exchange (ETDEWEB)

    Grebe, E.; Schaeffer, D.J. (Univ. of Illinois, Urbana (United States))

    1991-05-01

    The authors are developing bioassays which use planarians (free-living platyhelminthes) for the rapid determination of various types of toxicity, including acute mortality, tumorigenicity, and short-term neurobehavioral responses. Their motivation for using these animals is due to their importance as components of the aquatic ecology of unpolluted streams their sensitivity to low concentrations of environmental toxicants and the presence of a sensitive neurological system with a true brain which allows for complex social behavior. A previous paper described the results of a neurobehavioral bioassay using phenol in a crossover study. This paper reports a similar crossover study using cadmium sulfate.

  4. Risk communication concerning welding fumes for the primary preventive care of welding apprentices in southern Brazil.

    Science.gov (United States)

    Cezar-Vaz, Marta Regina; Bonow, Clarice Alves; Vaz, Joana Cezar

    2015-01-19

    This study's aim was to assess the perceptions of welding apprentices concerning welding fumes being associated with respiratory and cardiovascular disorders and assess the implementation of risk communication as a primary prevention tool in the welding training process. This quasi-experimental, non-randomized study with before-and-after design was conducted with 84 welding apprentices in Southern Brazil. Poisson Regression analysis was used. Relative Risk was the measure used with a 95% confidence interval and 5% (p ≤ 0.05) significance level. Significant association was found between perceptions of worsened symptoms of respiratory disorders caused by welding fumes and educational level (p = 0.049), the use of goggles to protect against ultraviolet rays (p = 0.023), and access to services in private health facilities without insurance coverage (p = 0.001). Apprentices younger than 25 years old were 4.9 times more likely to perceive worsened cardiovascular symptoms caused by welding fumes after risk communication (RR = 4.91; CI 95%: 1.09 to 22.2). The conclusion is that risk communication as a primary preventive measure in continuing education processes implemented among apprentices, who are future welders, was efficacious. Thus, this study confirms that risk communication can be implemented as a primary prevention tool in welding apprenticeships.

  5. Electrospun Ultrafine Fiber Composites Containing Fumed Silica: From Solution Rheology to Materials with Tunable Wetting.

    Science.gov (United States)

    Dufficy, Martin K; Geiger, Mackenzie T; Bonino, Christopher A; Khan, Saad A

    2015-11-17

    Fumed silica (FS) particles with hydrophobic (R805) or hydrophilic (A150) surface functionalities are incorporated in polyacrylonitrile (PAN) fibers by electrospinning to produce mats with controlled wettability. Rheological measurements are conducted to elucidate the particle-polymer interactions and characterize the system while microscopic and analytic tools are used to examine FS location within both fibers and films to aid in the fundamental understanding of wetting behavior. Unlike traditional polymers, we find these systems to be gel-like, yet electrospinnable; the fumed silica networks break down into smaller aggregates during the electrospinning process and disperse both within and on the surface of the fibers. Composite nanofiber mats containing R805 FS exhibit an apparent contact angle over 130° and remain hydrophobic over 30 min, while similar mats with A150 display rapid surface-wetting with a static contact angle of ∼30°. Wicking experiments reveal that the water absorption properties can be further manipulated, with R805 FS-impregnated mats taking up only 8% water relative to mat weight in 15 min. In contrast, PAN fibers containing A150 FS absorb 425% of water in the same period, even more than the pure PAN fiber (371%). The vastly different responses to water demonstrate the versatility of FS in surface modification, especially for submicron fibrous mats. The role of fumed silica in controlling wettability is discussed in terms of their surface functionality, placement on nanofibers and induced surface roughness.

  6. A comparative evaluation of metakaolin and silica fume to control alkali-silica reaction in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Nkinamubanzi, P.C.; Fournier, B.; Chevrier, R. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Materials Technology Laboratory

    2007-07-15

    This study evaluated the efficacy of different types of cementing materials. An accelerated modified mortar bar test was used to evaluate the efficacy of supplementary cementing materials (SCMs) including silica fume, metakaolin, fly ash, and slag in binary and ternary cementitious systems. Spratt and Sudbury aggregates were used as reference reactive aggregates. Thermal analyses of past specimens incorporating silica fume and metakaolin were conducted. The role of alkalis in pozzolanic reaction products through pore solution analysis on paste specimens was also investigated. The study showed that additions of metakaolin was needed to achieve expansion reductions similar to reductions obtained using silica fume. The cause was attributed to the lower alkali binding capacity and portlandite consumption of the metakaolin material. The study also showed that the efficacy of the SCMs in counteracting alkali-silica reactions (ASR) in concrete varied widely depending on the nature and the composition of the materials used, as well as on the reactivity level of the aggregates and the proportion of the SCMs in the concrete mixtures. 17 refs., 10 tabs., 19 figs, 2 appendices.

  7. Exposure to Cooking Oil Fumes and Oxidative Damages: A Longitudinal Study in Chinese Military Cooks

    Science.gov (United States)

    Lai, Ching-Huang; Jaakkola, Jouni J.K.; Chuang, Chien-Yi; Liou, Saou-Hsing; Lung, Shih-Chun; Loh, Ching-Hui; Yu, Dah-Shyong; Strickland, Paul T.

    2014-01-01

    Cooking oil fumes contain polycyclic aromatic hydrocarbons (PAHs), heterocyclic aromatic amines, benzene, and formaldehyde which may cause oxidative damages to DNA and lipids. We assessed the relations between exposure to cooking oil fumes (COF) and subsequent oxidative DNA damage and lipid peroxidation among military cooks and office-based soldiers. The study population, including 61 Taiwanese male military cooks and a reference group of 37 office soldiers, collected urine samples pre-shift of the first weekday and post-shift of the fifth workday. We measured airborne particulate PAHs in military kitchens and offices and concentrations of urinary 1-OHP, a biomarker of PAH exposure, urinary 8-hydroxydeoxyguanosine (8-OHdG), a biomarkers of oxidative DNA damage, and urinary isoprostane (Isop). Airborne particulate PAHs levels in kitchens significantly exceeded those in office areas. The concentrations of urinary 1-OHP among military cooks increased significantly after 5 days of exposure to COF. Using generalized estimating equation (GEE) analysis adjusting for confounding, a change in log(8-OHdG) and log(Isop) were statistically significantly related to a unit change in log(1-OHP) (regression coefficient [β], β= 0.06, 95% CI 0.001 to 0.12) and (β= 0.07, 95% CI 0.001 to 0.13), respectively. Exposure to PAHs, or other compounds in cooking-oil fumes, may cause both oxidative DNA damage and lipid peroxidation. PMID:22968348

  8. Comparison of Powder Dusting and Cyanoacrylate Fuming Techniques in Retrieving Latent Fingerprint Exposed to Environment Conditions

    International Nuclear Information System (INIS)

    Mayalvanan, Y.; Sri Pawita Albakri Amir Hamzah; Chuan, L.L.; Muhamad Hilmi Baba; Amidon Anan

    2014-01-01

    Latent fingerprints are one of the best evidence to prove the presence of an individuals presence at the crime scene. There are many techniques available for a successful fingerprint lifting. Two of the most common ones are fingerprint powder dusting and cyanoacrylate fuming. This research aims to compare both techniques and determine which has a higher success rate in retrieving fingerprints exposed to local environmental conditions for three days. Fingerprint samples were collected from 18 subjects on glass, perspex and aluminium slides. These samples were then exposed to local environmental conditions for three days. The fingerprints were then developed using the aforementioned techniques. Based on the results, it can be safely said that, fuming results in clearer fingerprints and more minutiae can be found from the retrieved fingerprints even with exposure to less than optimum local conditions. This proves that fuming is a better fingerprint lifting method to resolve latent fingerprint compared to powder dusting. Surface on which the fingerprint is retrieved from influences the quality of clarity of a latent fingerprint. (author)

  9. Factors Affecting the Capture Efficiency of a Fume Extraction Torch for Gas Metal Arc Welding.

    Science.gov (United States)

    Bonthoux, Francis

    2016-07-01

    Welding fumes are classified as Group 2B 'possibly carcinogenic' and this prompts to the implementation of local exhaust ventilation (LEV). The fume extraction torch with LEV integrated into the tool is the most attractive solution but its capture efficiency is often disappointing in practice. This study assesses the main parameters affecting fume capture efficiency namely the extraction flow rate, the positioning of the suction openings on the torch, the angle of inclination of the torch to the workpiece during welding, the metal transfer modes, and the welding deposition rate. The theoretical velocity induced by suction, estimated from the extraction flow rate and the position of the suction openings, is the main parameter affecting effectiveness of the device. This is the design parameter and its value should never be Welding with high deposition rates (>1.1g s(-1)) and spray transfer leads to low capture efficiency if induced velocities are <0.5 m s(-1) The results of the study can be used in the design of integrated on-torch extraction systems and provide information for fixing system objectives. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  10. [Study on the chemical components of edible oil fume in kitchen and its genotoxity on Drosophila].

    Science.gov (United States)

    Li, S; Wang, Y; Zhang, J; Zhao, X

    1999-01-30

    To study the chemical components of the condensate of edible oil fume in kitchen and its genotoxicity on Drosophila. Analysis for the chemical components was carried out by gas chromatography and mass spectra (GC/MS) and its genotoxicity was studied by sex linked recessive lethal (SLRL) test in Drosophila. A total of 74 organic compounds were found in samples of condensed oil from the fume in kitchen. It included hydroxylic acids, hydrocarbons, alcohols, esters, aldehydes, ketones, aromatic compounds, and steroids, etc. The total mutagenicity rates in SLRL test induced by the samples at concentrations of 110,320 and 960 mg/L were 0.1732%, 0.4306% and 0.1707% respectively. The sterility rates of the first broods were 2.564%, 2.056% and 2.845% at above 3 concentrations respectively(P < 0.05, as compared with the control). The mutagenicity rate of the second brood at 320 mg/L was 0.530% and that of the third brood at 110 mg/L 0.540%(P < 0.001). Some of the compounds in the condensate of edible oil fume were proved to have high recessive lethal effect and genotoxic effect on the reproductive system of Drosophila.

  11. Rapid Detection of Transition Metals in Welding Fumes Using Paper-Based Analytical Devices

    Science.gov (United States)

    Volckens, John

    2014-01-01

    Metals in particulate matter (PM) are considered a driving factor for many pathologies. Despite the hazards associated with particulate metals, personal exposures for at-risk workers are rarely assessed due to the cost and effort associated with monitoring. As a result, routine exposure assessments are performed for only a small fraction of the exposed workforce. The objective of this research was to evaluate a relatively new technology, microfluidic paper-based analytical devices (µPADs), for measuring the metals content in welding fumes. Fumes from three common welding techniques (shielded metal arc, metal inert gas, and tungsten inert gas welding) were sampled in two welding shops. Concentrations of acid-extractable Fe, Cu, Ni, and Cr were measured and independently verified using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results from the µPAD sensors agreed well with ICP-OES analysis; the two methods gave statistically similar results in >80% of the samples analyzed. Analytical costs for the µPAD technique were ~50 times lower than market-rate costs with ICP-OES. Further, the µPAD method was capable of providing same-day results (as opposed several weeks for ICP laboratory analysis). Results of this work suggest that µPAD sensors are a viable, yet inexpensive alternative to traditional analytic methods for transition metals in welding fume PM. These sensors have potential to enable substantially higher levels of hazard surveillance for a given resource cost, especially in resource-limited environments. PMID:24515892

  12. Nano-Sized Fume Biogas Production from Food Waster Using Semi-Continuous Anaerobic Digester.

    Science.gov (United States)

    Park, Keum-Joo; Seo, Seong-Gyu; Kim, Eun-Sik; Islam, M N; Song, Hyung-Woon; Yoon, Hyung-Sun

    2018-02-01

    In this study, the nano-sized fume biogas production from food waste was investigated using lab scale semi-continuous stirred tank reactor (SCSTR) at 35 °C with 30d HRT and 30L working volume. The mesophilic digestion test was performed with three different feed materials (food waste) and food to microorganism (F/M) ratios (0.13, 0.34, and 0.27) in the same experiment. The results showed that the F/M ratios significantly affected the biogas production rate. The highest production rate was obtained at F/M ratio of 0.13. Nano-sized fume biogas produced in anaerobic digestion consists of 68.7% CH4, 31.2% CO2 and 30~200 nm particle. The average nano-sized fume biogas and methane production of digester were 29.96 L/Kg versus day-1 and 20.58 L/Kg versus day-1, respectively. The CH4 could be calculated as the heat energy 1.85 Kcal/Kg VS day-1. The digestion was operated without addition of chemicals or nutrients into the system.

  13. Risk Communication Concerning Welding Fumes for the Primary Preventive Care of Welding Apprentices in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Marta Regina Cezar-Vaz

    2015-01-01

    Full Text Available This study’s aim was to assess the perceptions of welding apprentices concerning welding fumes being associated with respiratory and cardiovascular disorders and assess the implementation of risk communication as a primary prevention tool in the welding training process. This quasi-experimental, non-randomized study with before-and-after design was conducted with 84 welding apprentices in Southern Brazil. Poisson Regression analysis was used. Relative Risk was the measure used with a 95% confidence interval and 5% (p ≤ 0.05 significance level. Significant association was found between perceptions of worsened symptoms of respiratory disorders caused by welding fumes and educational level (p = 0.049, the use of goggles to protect against ultraviolet rays (p = 0.023, and access to services in private health facilities without insurance coverage (p = 0.001. Apprentices younger than 25 years old were 4.9 times more likely to perceive worsened cardiovascular symptoms caused by welding fumes after risk communication (RR = 4.91; CI 95%: 1.09 to 22.2. The conclusion is that risk communication as a primary preventive measure in continuing education processes implemented among apprentices, who are future welders, was efficacious. Thus, this study confirms that risk communication can be implemented as a primary prevention tool in welding apprenticeships.

  14. Development of Welding Fumes Health Index (WFHI) for Welding Workplace's Safety and Health Assessment.

    Science.gov (United States)

    Hariri, Azian; Paiman, Nuur Azreen; Leman, Abdul Mutalib; Md Yusof, Mohammad Zainal

    2014-08-01

    This study aimed to develop an index that can rank welding workplace that associate well with possible health risk of welders. Welding Fumes Health Index (WFHI) were developed based on data from case studies conducted in Plant 1 and Plant 2. Personal sampling of welding fumes to assess the concentration of metal constituents along with series of lung function tests was conducted. Fifteen metal constituents were investigated in each case study. Index values were derived from aggregation analysis of metal constituent concentration while significant lung functions were recognized through statistical analysis in each plant. The results showed none of the metal constituent concentration was exceeding the permissible exposure limit (PEL) for all plants. However, statistical analysis showed significant mean differences of lung functions between welders and non-welders. The index was then applied to one of the welding industry (Plant 3) for verification purpose. The developed index showed its promising ability to rank welding workplace, according to the multiple constituent concentrations of welding fumes that associates well with lung functions of the investigated welders. There was possibility that some of the metal constituents were below the detection limit leading to '0' value of sub index, thus the multiplicative form of aggregation model was not suitable for analysis. On the other hand, maximum or minimum operator forms suffer from compensation issues and were not considered in this study.

  15. Mechanisms of cadmium induced genomic instability

    International Nuclear Information System (INIS)

    Filipič, Metka

    2012-01-01

    Cadmium is an ubiquitous environmental contaminant that represents hazard to humans and wildlife. It is found in the air, soil and water and, due to its extremely long half-life, accumulates in plants and animals. The main source of cadmium exposure for non-smoking human population is food. Cadmium is primarily toxic to the kidney, but has been also classified as carcinogenic to humans by several regulatory agencies. Current evidence suggests that exposure to cadmium induces genomic instability through complex and multifactorial mechanisms. Cadmium dose not induce direct DNA damage, however it induces increase in reactive oxygen species (ROS) formation, which in turn induce DNA damage and can also interfere with cell signalling. More important seems to be cadmium interaction with DNA repair mechanisms, cell cycle checkpoints and apoptosis as well as with epigenetic mechanisms of gene expression control. Cadmium mediated inhibition of DNA repair mechanisms and apoptosis leads to accumulation of cells with unrepaired DNA damage, which in turn increases the mutation rate and thus genomic instability. This increases the probability of developing not only cancer but also other diseases associated with genomic instability. In the in vitro experiments cadmium induced effects leading to genomic instability have been observed at low concentrations that were comparable to those observed in target organs and tissues of humans that were non-occupationally exposed to cadmium. Therefore, further studies aiming to clarify the relevance of these observations for human health risks due to cadmium exposure are needed.

  16. Cadmium risks to freshwater life: derivation and validation of low-effect criteria values using laboratory and field studies

    Science.gov (United States)

    Mebane, Christopher A.

    2006-01-01

    In 2001, the U.S. Environmental Protection Agency (EPA) released updated aquatic life criteria for cadmium. Since then, additional data on the effects of cadmium to aquatic life have become available from studies supported by the EPA, Idaho Department of Environmental Quality (IDEQ), and the U.S. Geological Survey, among other sources. Updated data on the effects of cadmium to aquatic life were compiled and reviewed and low-effect concentrations were estimated. Low-effect values were calculated using EPA's guidelines for deriving numerical national water-quality criteria for the protection of aquatic organisms and their uses. Data on the short-term (acute) effects of cadmium on North American freshwater species that were suitable for criteria derivation were located for 69 species representing 57 genera and 33 families. For longer-term (chronic) effects of cadmium on North American freshwater species, suitable data were located for 28 species representing 21 genera and 17 families. Both the acute and chronic toxicity of cadmium were dependent on the hardness of the test water. Hardness-toxicity regressions were developed for both acute and chronic datasets so that effects data from different tests could be adjusted to a common water hardness. Hardness-adjusted effects values were pooled to obtain species and genus mean acute and chronic values, which then were ranked by their sensitivity to cadmium. The four most sensitive genera to acute exposures were, in order of increasing cadmium resistance, Oncorhynchus (Pacific trout and salmon), Salvelinus ('char' trout), Salmo (Atlantic trout and salmon), and Cottus (sculpin). The four most sensitive genera to chronic exposures were Hyalella (amphipod), Cottus, Gammarus (amphipod), and Salvelinus. Using the updated datasets, hardness dependent criteria equations were calculated for acute and chronic exposures to cadmium. At a hardness of 50 mg/L as calcium carbonate, the criterion maximum concentration (CMC, or 'acute

  17. Toxicity of Cadmium, Copper, and Zinc to the Threatened Chiricahua Leopard Frog (Lithobates [Rana] chiricahuensis).

    Science.gov (United States)

    Calfee, Robin D; Little, Edward E

    2017-12-01

    The Chiricahua leopard frog (Lithobates chiricahuensis) is in decline throughout the western United States, and is particularly sensitive to physical, chemical and biotic changes in their habitat. Acute toxicity tests revealed that among the metals detected in Chiricahua leopard frog habitat, copper was toxic at concentrations lower than those observed in the environment. Developing tadpoles were chronically exposed for 60 days to cadmium, copper and zinc because of the potential for long term exposure to these metals during early development. Cadmium was toxic, but at concentrations above observed environmental levels. Copper was especially toxic to this species at concentrations of about 10% of concentrations observed in their habitats. The onset of toxicity occurred within a few days of exposure, thus pulsed exposures from rain events could potentially be acutely toxic to tadpoles of this species. Zinc did not appear to have a negative impact during the acute or chronic exposures.

  18. Welding fumes exposure decreases forced vital capacity but not height among welders

    Directory of Open Access Journals (Sweden)

    Titis Mariyamah

    2012-09-01

    Full Text Available AbstrakLatar belakang: Asap pengelasan antara lain dapat menyebabkan penurunan kapasitas vital paksa (KVP. Tujuan penelitian ini adalah untuk mengidentifi kasi beberapa faktor yang dapat berhubungan dengan KVP pada pengelas.Metode: Studi ini menggunakan desain potong lintang pada subjek pengelas di pabrik mobil sekitar Jakarta tahun 2012. Responden dipilih secara purposif. Pemeriksaan KVP menggunakan spirometri. Data pajanan asap didapatkan dari data yang dimiliki perusahaan. Data demografi , kebiasaan, dan pekerjaan diperoleh dengan wawancara.Hasil: Jumlah responden 124 dari 150, rentang umur 19-55 tahun dan telah bekerja antara 1-16 tahun. Data pajanan asap pada area pengelasan adalah 15 mg/m3, Pajanan asap pengelasan cenderung menurunkan kapasitas vital paksa [koefi sient regresi (r = -0,004, 95% interval kepercayaan (CI = -0,01;-0,00] dan makin tinggi tinggi badan cenderung KVP meningkat (r= 0,35; 95% CI = 0,02;0,05.Kesimpulan: Pajanan asap pengelasan cenderung menurunkan KVP, sebaliknya semakin tinggi tinggi badan cenderung meningkatkan KVP. (Health Science Indones 2012;1:41-4Kata kunci: pajanan asap pengelasan, tinggi badan, kapasitas vital paksaAbstractBackground: Welding fumes caused the decreasing of forced vital capacity (FVC. The study aimed to identify several factors related to FVC.Methods: The subject of this cross-sectional study consisted of welders in an automobile manufacture outskirt of Jakarta in 2012. We used purposive sampling selection. The assessments of FVC were using spirometri. Exposure fumes value of the workplace based on the assessements of the factory. Demographic and employment data was selected from interview.Results: A number 124 out of 150 welders which aged between 19-55 years who’s had 1-16 years worked. Exposure fumes value was 15 mg/m3 in the factory. The welding fume exposure decreased FVC [regressioncoeffi cient (r = -0.004; 95% confi dence interval (CI = -0.01;-0.00]. On the other site, those who had

  19. Radionuclide study of the action of cadmium on alveolar macrophages

    International Nuclear Information System (INIS)

    Reulet, Maryse.

    1976-01-01

    The experimental toxicity of cadmium was studied on the lung, using cadmium sulfate, cadmium acetate and the radioactive isotope cadmium 109 in chloride or acetate form. The results are given in the following order: part one is devoted to the results of investigations on chronic cadmium poisoning and the role of alveolar macrophages in this poisoning; in part two the uptake of cadmium on alveolar macrophages is studied with cadmium 109, administered intraperitoneally; in part three the action of cadmium on the phospholipid metabolism of alveolar macrophages is examined. The cadmium, as sulfate or acetate, is administered in several ways: by intraperitoneal injection; or by inhalation of cadmium dusts or aerosols. The effect of cadmium on the oxidative metabolism of alveolar macrophages is studied in part four. This work is carried out 'in vitro' and 'in vivo' after cadmium oxide dusting of the air [fr

  20. Cadmium resistance in Drosophila: a small cadmium binding substance

    International Nuclear Information System (INIS)

    Jacobson, K.B.; Williams, M.W.; Richter, L.J.; Holt, S.E.; Hook, G.J.; Knoop, S.M.; Sloop, F.V.; Faust, J.B.

    1985-01-01

    A small cadmium-binding substance (CdBS) has been observed in adult Drosophila melanogaster that were raised for their entire growth cycle on a diet that contained 0.15 mM CdCl 2 . Induction of CdBS was observed in strains that differed widely in their sensitivity of CdCl 2 . This report describes the induction of CdBS and some of its characteristics. 17 refs., 4 figs., 1 tab

  1. Cadmium and Cadmium/Zinc Ratios and Tobacco-Related Morbidities

    Directory of Open Access Journals (Sweden)

    Patricia Richter

    2017-09-01

    Full Text Available Metals are one of five major categories of carcinogenic or toxic constituents in tobacco and tobacco smoke. Cadmium is highly volatile and a higher percentage of the total tobacco cadmium content is efficiently transferred to mainstream tobacco smoke than many other toxic metals in tobacco. Inhaled cadmium bioaccumulates in the lungs and is distributed beyond the lungs to other tissues, with a total body biological half-life of one to two decades. Chronic cadmium exposure through tobacco use elevates blood and urine cadmium concentrations. Cadmium is a carcinogen, and an inducer of proinflammatory immune responses. Elevated exposure to cadmium is associated with reduced pulmonary function, obstructive lung disease, bronchogenic carcinoma, cardiovascular diseases including myocardial infarction, peripheral arterial disease, prostate cancer, cervical cancer, pancreatic cancer, and various oral pathologies. Cadmium and zinc have a toxicologically inverse relationship. Zinc is an essential element and is reportedly antagonistic to some manifestations of cadmium toxicity. This review summarizes associations between blood, urine, and tissue cadmium concentrations with emphasis on cadmium exposure due to tobacco use and several disease states. Available data about zinc and cadmium/zinc ratios and tobacco-related diseases is summarized from studies reporting smoking status. Collectively, data suggest that blood, urine, and tissue cadmium and cadmium/zinc ratios are often significantly different between smokers and nonsmokers and they are also different in smokers for several diseases and cancers. Additional biomonitoring data such as blood or serum and urine zinc and cadmium levels and cadmium/zinc ratios in smokers may provide further insight into the development and progression of diseases of the lung, cardiovascular system, and possibly other organs.

  2. Cadmium and Cadmium/Zinc Ratios and Tobacco-Related Morbidities

    OpenAIRE

    Patricia Richter; Obaid Faroon; R. Steven Pappas

    2017-01-01

    Metals are one of five major categories of carcinogenic or toxic constituents in tobacco and tobacco smoke. Cadmium is highly volatile and a higher percentage of the total tobacco cadmium content is efficiently transferred to mainstream tobacco smoke than many other toxic metals in tobacco. Inhaled cadmium bioaccumulates in the lungs and is distributed beyond the lungs to other tissues, with a total body biological half-life of one to two decades. Chronic cadmium exposure through tobacco use ...

  3. Cadmium and Cadmium/Zinc Ratios and Tobacco-Related Morbidities.

    Science.gov (United States)

    Richter, Patricia; Faroon, Obaid; Pappas, R Steven

    2017-09-29

    Metals are one of five major categories of carcinogenic or toxic constituents in tobacco and tobacco smoke. Cadmium is highly volatile and a higher percentage of the total tobacco cadmium content is efficiently transferred to mainstream tobacco smoke than many other toxic metals in tobacco. Inhaled cadmium bioaccumulates in the lungs and is distributed beyond the lungs to other tissues, with a total body biological half-life of one to two decades. Chronic cadmium exposure through tobacco use elevates blood and urine cadmium concentrations. Cadmium is a carcinogen, and an inducer of proinflammatory immune responses. Elevated exposure to cadmium is associated with reduced pulmonary function, obstructive lung disease, bronchogenic carcinoma, cardiovascular diseases including myocardial infarction, peripheral arterial disease, prostate cancer, cervical cancer, pancreatic cancer, and various oral pathologies. Cadmium and zinc have a toxicologically inverse relationship. Zinc is an essential element and is reportedly antagonistic to some manifestations of cadmium toxicity. This review summarizes associations between blood, urine, and tissue cadmium concentrations with emphasis on cadmium exposure due to tobacco use and several disease states. Available data about zinc and cadmium/zinc ratios and tobacco-related diseases is summarized from studies reporting smoking status. Collectively, data suggest that blood, urine, and tissue cadmium and cadmium/zinc ratios are often significantly different between smokers and nonsmokers and they are also different in smokers for several diseases and cancers. Additional biomonitoring data such as blood or serum and urine zinc and cadmium levels and cadmium/zinc ratios in smokers may provide further insight into the development and progression of diseases of the lung, cardiovascular system, and possibly other organs.

  4. Effects of chelating agents on oral uptake and renal deposition and excretion of cadmium

    International Nuclear Information System (INIS)

    Engstroem, B.

    1984-01-01

    The gastrointestinal absorption, transport, tissue deposition and excretion of cadmium was studied in adult male mice given a single oral LD 50 dose of 109 Cd-labeled CdCl 2 alone or in combination with nitrilotriacetic acid (NTA), sodium tripolyphosphate (STPP) or ethylenediaminetetraacetic acid (EDTA). Blood, intestinal mucosa, liver and kidneys were analyzed for 109 Cd at different times after exposure and the influence of the chelating agents on Cd binding to metallothionein and other tissue ligands was also studied. The effect of different chelating agents on acute cadmium toxicity and metabolism seemed to be due to changes in the stability of the administered chelate complexes, due to variation in pH and to the availability of metal binding ligands such as metallothionein in vivo. NTA, STPP and EDTA had no effect on the metabolism or toxicity of cadmium after long-term low dose oral exposure. 43 references, 4 tables, 9 figures

  5. Electrodialytic Removal of Cadmium from Straw Ash

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne

    1999-01-01

    A problem with flyash from straw and wood combustion is the high level of heavy metals, especially cadmium. Two electrodialytic remediation experiments were carried out on cadmium polluted flyash from straw combustion. The flyash could be cleaned to 1/3 of its initial level after 24 days...... of remediation. Further removal of cadmium could be possible with longer remediation time or a higher current density...

  6. Cadmium telluride photovoltaic radiation detector

    Science.gov (United States)

    Agouridis, D.C.; Fox, R.J.

    A dosimetry-type radiation detector is provided which employs a polycrystalline, chlorine-compensated cadmium telluride wafer fabricated to operate as a photovoltaic current generator used as the basic detecting element. A photovoltaic junction is formed in the wafer by painting one face of the cadmium telluride wafer with an n-type semi-conductive material. The opposite face of the wafer is painted with an electrically conductive material to serve as a current collector. The detector is mounted in a hermetically sealed vacuum containment. The detector is operated in a photovoltaic mode (zero bias) while DC coupled to a symmetrical differential current amplifier having a very low input impedance. The amplifier converts the current signal generated by radiation impinging upon the barrier surface face of the wafer to a voltage which is supplied to a voltmeter calibrated to read quantitatively the level of radiation incident upon the detecting wafer.

  7. Distribution of cadmium between calcium carbonate and solution, 2

    International Nuclear Information System (INIS)

    Kitano, Yasushi; Kanamori, Nobuko; Fujiyoshi, Ryoko

    1978-01-01

    The distribution coefficient of cadmium between calcite and solution has been measured in the calcium bicarbonate solution containing cadmium and chloride ions, which forms complexes with cadmium ions. It has been confirmed experimentally that cadmium carbonate is present as a solid solution between calcitic calcium carbonate and cadmium carbonate in the carbonate precipitate formed in the solution system. However, the constant value of the thermodynamic distribution coefficient of cadmium between calcite and solution has not been obtained experimentally in the calcium bicarbonate solution containing cadmium and chloride ions. It may have been caused by the very specific behavior of cadmium ions, but the exact reason remains unsolved and must be studied. (Kobatake, H.)

  8. Cadmium Toxicity to Ringed Seals (Phoca hispida)

    DEFF Research Database (Denmark)

    Sonne, Christian; Dietz, R.; Riget, F. F.

    Cadmium concentrations in kidneys from ringed seals (Phoca hispida) from North West Greenland (Qaanaaq) are high. Concentrations range at level known to induce renal toxic effects (mainly tubulopathy) and demineralisation (osteopenia) of the skeletal system (Fanconi's Syndrome) in humans as well...... as laboratory mammals. We have studied possible cadmium induced histopathological changes in the kidneys as well as a demineralisation of the skeletal system (DXA-scanning of lumbal vertebraes). No obvious cadmium induced toxic changes were found. Food composition and physiological adaptations may explain...... the absence of toxic effects of cadmium in ringed seal...

  9. Acquisition of apoptotic resistance in cadmium-induced malignant transformation: specific perturbation of JNK signal transduction pathway and associated metallothionein overexpression.

    Science.gov (United States)

    Qu, Wei; Fuquay, Richard; Sakurai, Teruaki; Waalkes, Michael P

    2006-08-01

    Prior work has shown that chronic cadmium exposed rat liver epithelial cells (CCE-LE) become malignantly transformed after protracted low level cadmium exposure. Acquisition of apoptotic resistance is common in oncogenesis and the present work explores this possibility in CCE-LE cells. CCE-LE cells were resistant to apoptosis induced by etoposide or an acute high concentration of cadmium as assessed by flow cytometry with annexin/FITC. Three key mitogen-activated protein kinases (MAPKs), namely ERK1/2, JNK1/2, and p38, were phosphorylated in CCE-LE cells after acute cadmium exposure. However, the levels of phosphorylated JNK1/2 were markedly decreased in CCE-LE cells compared to control. JNK kinase activity was also suppressed in CCE-LE cells exposed to cadmium. Epidermal growth factor (EGF), used as a positive control for stimulating JNK phosphorylation, was much less effective in CCE-LE cells than control cells. Ro318220 (Ro), a strong activator of JNK, increased phosphorylated JNK1/2 to levels similar to the cadmium-treated control cells and also enhanced apoptosis in response to cadmium in CCE-LE cells. Metallothionein (MT), which is thought to potentially inhibit apoptosis, was strongly overexpressed in CCE-LE cells. Further, in MT knockout (MT-/-) fibroblasts, JNK1/2 phosphorylation was markedly increased after cadmium exposure compared with similarly treated wild-type (MT+/+) cells. These results indicate cadmium-transformed cells acquired apoptotic resistance, which may be linked to the specific suppression of the JNK pathway and is associated with MT overexpression, which, in turn, may impact this signal transduction pathway. The acquisition of apoptotic resistance may play an important role in cadmium carcinogenesis by contributing to both tumor initiation and malignant progression.

  10. Lead and cadmium in food

    International Nuclear Information System (INIS)

    Gliesmann, S.; Kruse, H.; Kriews, M.; Mangels, H.

    1992-08-01

    The amounts of lead and cadmium produced and processed in these days are considerable. As a result, our environment is increasingly polluted by heavy metals and industrial installations, motor vehicles or incinerating plants appear to be among the main culprits here. Air and water are the media permitting the entry of heavy metals into our natural environment where they accumulate in the soil and then gradually migrate into the plants. Their further transport in the food constitutes the third step in the environmental spread of heavy metals. The consumption of muscle and organ meats, of vegetables, fruits, canned food and drinking water is unavoidably associated with some ingestion of lead and cadmium. The degree to which they are taken up and stored in different tissues is determined by absorption properties and the nutritional state of the organism. Cadmium tends to accumulate in the kidneys, lead is mainly stored in the bones. A continuously increasing uptake finally results in health injuries that range from unspecific complaints to damaged kidneys or bones and disorders of liver function. Children and elderly people are at a particular risk here. The level of food contamination is such that screening for heavy metals must be rigorously carried out once appropriate legal thresholds have been set, which ought to be based on proven detrimental effects of lead and cadmium on our health and also take account of infants and children or any other risk groups, where particular caution must be exercised. It should be pointed out that such thresholds have so far not been determined. (orig./MG) [de

  11. Toxicity and Bioconcentration of Cadmium and Copper in Artemia Urmiana Nauplii

    Directory of Open Access Journals (Sweden)

    Mohammad Mohiseni

    2017-01-01

    Full Text Available Background: Artemia urmiana are small crustaceans that because of its non-selective filter feeder pattern potentially may absorb high level of heavy metals through their living environment. In this study, the effects of different levels of cadmium and copper on survival, catalase activity and metals bioconcentration rates in A. urmiana nauplii have been investigated. Methods: The research was carried out in February 2012 at University of Tehran, Tehran, Iran. First experiment was conducted in nine concentrations with six replication, then LC50 and probable interactions between experimental metals were evaluated. In the second experiment, concentrations of metals absorbed by Artemia and catalase activity were measured based on the acute toxicity indices, including NOEC, LOEC and LC50 at individual and mixed concentrations. Results: The toxicity of copper sulphate (LC50= 29.87 was 2.5 times greater than cadmium chloride (LC50=79.08 and the toxicity interaction between cadmium and copper was synergistic. The rate of copper uptake in Artemia was higher than cadmium and increased concentration of heavy metals significantly decreased the bioconcentration factor. Comparison of mixed and individual concentrations showed that cadmium significantly decreased copper uptake, while it seems that cadmium bioconcentration was improved consequently. Biochemical analysis showed that the catalase activity was affected undesirably in different individual and mixed concentrations; however, these changes were not significant. Conclusion: A. urmiana nauplia seems to be highly resistant toward cadmium and copper in their culture medium and demonstrated excessive potential for uptake of heavy metals from their rearing environment.

  12. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; Vijayan, Mathilakath M.

    2011-01-01

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  13. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Vijayan, Mathilakath M., E-mail: mvijayan@uwaterloo.ca [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2011-05-15

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  14. Effects of cadmium on the glial architecture in lizard brain

    Directory of Open Access Journals (Sweden)

    Rossana Favorito

    2017-01-01

    Full Text Available The glial cells are positioned to be the first cells of the brain parenchyma to face molecules crossing the blood-brain barrier with a relevant neuroprotective role from cytotoxic action of heavy metals on the nervous system. Cadmium is a highly toxic metal and its levels in the environment are increasing due to industrial activities. This element can pass the blood-brain barrier and have neurotoxic activity. For this reason we have studied the effects of cadmium on the glial architecture in the lizard Podarcis siculus, a significant bioindicator of chemical exposure due to its persistence in a variety of habitats. The study was performed on two groups of lizards. The first group of P. siculus was exposed to an acute treatment by a single i.p. injection (2 mg/kg-BW of CdCl2 and sacrificed after 2, 7 and 16 days. The second one was used as control. The histology of the brain was studied by Hematoxylin/Eosin and Cresyl/Violet stains while the glial structures were analyzed by immunodetection of the glial fibrillary acidic protein (GFAP, the most widely accepted marker for astroglial cells. Evident morphological alterations of the brain were observed at 7 and 16 days from the injection, when we revealed also a decrease of the GFAP-immunopositive structures in particular in the rhombencephalic ventricle, telencephalon and optic tectum. These results show that in the lizards an acute exposure to cadmium provokes morphological cellular alterations in the brain but also a decrement of the expression of GFAP marker with possible consequent damage of glial cells functions.

  15. Serious pneumococcal disease outbreak in men exposed to metal fume - detection, response and future prevention through pneumococcal vaccination.

    Science.gov (United States)

    Ewing, Judith; Patterson, Lynsey; Irvine, Neil; Doherty, Lorraine; Loughrey, Anne; Kidney, Joe; Sheppard, Carmen; Kapatai, Georgia; Fry, Norman K; Ramsay, Mary; Jessop, Lucy

    2017-07-13

    Welders and those exposed to metal fume are known to be at increased risk of pneumococcal pneumonia and invasive pneumococcal disease. Current UK guidance recommends that vaccination against pneumococcus be considered in those at risk of frequent or continuous occupational exposure to metal fume, taking into account the exposure control measures in place. We report an outbreak of serious pneumococcal disease that occurred between April and June 2015 among a multinational workforce exposed to metal fumes while working on the refurbishment of an oil rig in a Belfast shipyard. Four confirmed and five probable cases were identified, which occurred despite the use of environmental control measures and the availability of respiratory protective equipment. To provide direct protection to those at risk of pneumococcal disease and to eradicate carriage of pneumococcus and interrupt transmission, pneumococcal polysaccharide vaccine (PPV23) and antibiotic prophylaxis were offered to 680 individuals identified as potentially exposed to metal fume. Low levels of prior pneumococcal vaccination were reported among this target group (vaccine-preventable strains covered by the conjugate and polysaccharide pneumococcal vaccines currently available. We propose that consideration should be given to strengthening implementation around pneumococcal vaccination for those exposed to metal fume through their work, even when other control measures are in place, to reduce the risk of future cases and outbreaks of serious pneumococcal disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Systemic serum amyloid A as a biomarker for exposure to zinc and/or copper-containing metal fumes.

    Science.gov (United States)

    Baumann, R; Gube, M; Markert, A; Davatgarbenam, S; Kossack, V; Gerhards, B; Kraus, T; Brand, P

    2018-01-01

    Zinc- and copper-containing welding fumes increase systemic C-reactive protein (CRP). The aim of this study was to investigate the performance of the biomarkers serum amyloid A (SAA) and soluble vascular cell adhesion molecule-1 (VCAM-1) in this regard. Fifteen male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc for 6 h. Plasma samples were collected before, 6 and 24 h after start of exposure and biomarkers therein were measured by electrochemiluminescent assay. For each exposure, systemic concentrations of systemic SAA, but not VCAM-1, increased significantly at 24 h after exposure start compared with baseline ("copper only": P=0.0005, "zinc only": P=0.027, "copper and zinc": P=0.001). SAA showed a wider range of concentrations than did CRP and its levels increased up to 19-fold after welding fume exposure. The recognition of copper as a potential harmful component in welding fumes, also independent from zinc, deserves further consideration. SAA might represent a new sensitive biomarker for potential subclinical sterile inflammation after inhalation of copper- and/or zinc-containing welding fumes. As elevations of CRP and SAA protein have both been linked to a higher risk for cardiovascular disease, these findings might particularly be important for long-term welders.

  17. p53-dependent but ATM-independent inhibition of DNA synthesis and G2 arrest in cadmium-treated human fibroblasts

    International Nuclear Information System (INIS)

    Cao Feng; Zhou Tong; Simpson, Dennis; Zhou Yingchun; Boyer, Jayne; Chen Bo; Jin Taiyi; Cordeiro-Stone, Marila; Kaufmann, William

    2007-01-01

    This study focused on the activation of cell cycle checkpoint responses in diploid human fibroblasts that were treated with cadmium chloride and the potential roles of ATM and p53 signaling pathways in cadmium-induced responses. The alkaline comet assay indicated that cadmium caused a dose-dependent increase in DNA damage. Cells that were rendered p53-defective by expression of a dominant-negative p53 allele or knockdown of p53 mRNA were more resistant to cadmium-induced inactivation of colony formation than normal and ataxia telangiectasia (AT) cells. Synchronized fibroblasts in S were more sensitive to cadmium toxicity than cells in G1, suggesting that cadmium may target some element of DNA replication. Cadmium produced a dose- and time-dependent inhibition of DNA synthesis. An immediate inhibition was associated with severe delay in progression through S phase and a delayed inhibition seen 24 h after treatment was associated with accumulation of cells in G2. AT and normal cells displayed similar patterns of inhibition of DNA synthesis and G2 delay after treatment with cadmium, while p53-defective cells displayed significantly less of the delayed inhibition of DNA synthesis and accumulation in G2 post-treatment. Total p53 protein and ser15-phosphorylated p53 were induced by cadmium in normal and AT cells. The p53 transactivation target Gadd45α was induced in both p53-effective and p53-defective cells after 4 h cadmium treatment, and this was associated with an acute inhibition of mitosis. Cadmium produced a very unusual pattern of toxicity in human fibroblasts, inhibiting DNA replication and inducing p53-dependent growth arrest but without induction of p21 Cip1/Waf1 or activation of Chk1

  18. Improvement of cadmium phytoremediation after soil inoculation with a cadmium-resistant Micrococcus sp.

    Science.gov (United States)

    Sangthong, Chirawee; Setkit, Kunchaya; Prapagdee, Benjaphorn

    2016-01-01

    Cadmium-resistant Micrococcus sp. TISTR2221, a plant growth-promoting bacterium, has stimulatory effects on the root lengths of Zea mays L. seedlings under toxic cadmium conditions compared to uninoculated seedlings. The performance of Micrococcus sp. TISTR2221 on promoting growth and cadmium accumulation in Z. mays L. was investigated in a pot experiment. The results indicated that Micrococcus sp. TISTR2221significantly promoted the root length, shoot length, and dry biomass of Z. mays L. transplanted in both uncontaminated and cadmium-contaminated soils. Micrococcus sp. TISTR2221 significantly increased cadmium accumulation in the roots and shoots of Z. mays L. compared to uninoculated plants. At the beginning of the planting period, cadmium accumulated mainly in the shoots. With a prolonged duration of cultivation, cadmium content increased in the roots. As expected, little cadmium was found in maize grains. Soil cadmium was significantly reduced with time, and the highest percentage of cadmium removal was found in the bacterial-inoculated Z. mays L. after transplantation for 6 weeks. We conclude that Micrococcus sp. TISTR2221 is a potent bioaugmenting agent, facilitating cadmium phytoextraction in Z. mays L.

  19. Cadmium binding components in the supernatant fraction of the small intestinal mucosa of rats administered cadmium

    International Nuclear Information System (INIS)

    Taguchi, Tetsuya; Suzuki, Shosuke

    1978-01-01

    Cadmium binding protein was isolated by gel filtration from the supernatant fraction of the small intestines of rats continuously administered cadmium for 1, 3, 6, 9, 32 and 96 days. About two-thirds of the total amount of absorbed cadmium was associated with the cytosol of mucosal tissues scraped from the small intestines. Cadmium was almost always bound to proteins, molecular weights of which ranged from 5,400 to 9,800. Cadmium in livers and that in intestinal mucosa were in the same binding state, but as there was some lag period between the induction of the Cd-binding proteins of both tissues, the protein of the small intestinal mucosal cells must have been induced at the mucosa itself by contact with cadmium. The Cd-binding protein of the mucosal cells may play an important role in absorbing cadmium, because no other form of this metal was found in the mucosal cells of the small intestines. (Kobatake, H.)

  20. Welding fumes exposure, body mass index and duration of smoking decrease physical fi tness among welders

    Directory of Open Access Journals (Sweden)

    Rudy Wahyu Perdana

    2012-09-01

    Full Text Available AbstrakLatar belakang: Pajanan asap pengelasan dapat mengganggu kesehatan, antara lain penurunan kebugaran jasmani. Penelitian ini bertujuan menganalisis efek pajanan asap pengelasan terhadap kebugaran jasmani pengelas.Metode: Penelitian menggunakan desain potong lintang dan subjek penelitian dipilih secara purposif di antara pengelas di suatu pabrik knalpot di sekitar Jakarta tahun 2012. Beberapa karakteristik demografi , riwayat pekerjaan, dan kebiasaan subjek diperloleh dengan wawancara. Kebugaran jasmani diperiksa dengan metode Queen’s College Step Test. Total pajanan asap dinilai menggunakan metode semi kuantitatif yaitu perkalian pajanan asap dengan masa kerja sebagai pengelas.Hasil: Subjek penelitian berjumlah 110 orang, yang berusia antara 19-55 tahun, dengan masa kerja 1-16 tahun. Pajanan asap diperusahaan sebesar 15 mg/m3 menurut data pemeriksaan rutin perusahaan tahun 2012. Umur dan aktivitas fi sik tidak berkorelasi terhadap tingkat kebugaran jasmani pengelas. Akan tetapi didapatkan korelasi negatif antara total pajanan asap, index massa tubuh (IMT, dan kebiasaan lama merokok terhadap tingkat kebugaran jasmani pengelas. Korelasi terhadap tingkat kebugaran jasmani pengelas tersebut adalah: total pajanan asap [koefi sien regresi (r = -0,07; 95% koefi sien interval (CI = -0,10; -0,04]; IMT (r =-0,38; 95% CI = -0,64;-0,09; dan kebiasaan lama merokok (r = -0,16; 95% CI = -0,28;-0,04Kesimpulan: Peningkatan pajanan asap pengelasan, index massa tubuh, dan lama merokok menurunkan tingkat kebugaran jasmani pengelas. (Health Science Indones 2012;1:37-40Kata kunci: pajanan asap, kebugaran jasmani, Queen’s College Step Test AbstractBackground: Welding fumes exposure caused health disorders, one of them are decreasing the level of physical fi tness. This study aimed to analyze the effect of welding fumes exposure with the level of welder’sphysical fi tness.Methods: This cross-sectional using purposive selected by sampling selection method

  1. Evaluation of leakage from fume hoods using tracer gas, tracer nanoparticles and nanopowder handling test methodologies.

    Science.gov (United States)

    Dunn, Kevin H; Tsai, Candace Su-Jung; Woskie, Susan R; Bennett, James S; Garcia, Alberto; Ellenbecker, Michael J

    2014-01-01

    The most commonly reported control used to minimize workplace exposures to nanomaterials is the chemical fume hood. Studies have shown, however, that significant releases of nanoparticles can occur when materials are handled inside fume hoods. This study evaluated the performance of a new commercially available nano fume hood using three different test protocols. Tracer gas, tracer nanoparticle, and nanopowder handling protocols were used to evaluate the hood. A static test procedure using tracer gas (sulfur hexafluoride) and nanoparticles as well as an active test using an operator handling nanoalumina were conducted. A commercially available particle generator was used to produce sodium chloride tracer nanoparticles. Containment effectiveness was evaluated by sampling both in the breathing zone (BZ) of a mannequin and operator as well as across the hood opening. These containment tests were conducted across a range of hood face velocities (60, 80, and 100 ft/min) and with the room ventilation system turned off and on. For the tracer gas and tracer nanoparticle tests, leakage was much more prominent on the left side of the hood (closest to the room supply air diffuser) although some leakage was noted on the right side and in the BZ sample locations. During the tracer gas and tracer nanoparticle tests, leakage was primarily noted when the room air conditioner was on for both the low and medium hood exhaust airflows. When the room air conditioner was turned off, the static tracer gas tests showed good containment across most test conditions. The tracer gas and nanoparticle test results were well correlated showing hood leakage under the same conditions and at the same sample locations. The impact of a room air conditioner was demonstrated with containment being adversely impacted during the use of room air ventilation. The tracer nanoparticle approach is a simple method requiring minimal setup and instrumentation. However, the method requires the reduction in

  2. Assessment of aggregates- cement paste border in concretes containing silica fume and fly ash

    Directory of Open Access Journals (Sweden)

    Ali Sademomtazi

    2017-12-01

    Full Text Available The bond between aggregate and cement paste, called the interfacial transition zone (ITZ is an important parameter that effect on the mechanical properties and durability of concrete. Transition zone microstructure and porosity (pores of cement paste or concrete are affected by the type and properties of materials used which evaluated in this research. On the other hand, the use of efficient, low-cost and reliable method is particularly important for evaluating of concrete performance against the chloride ion penetration and its relationships with transition zone as a suitable index to assess the durability. So far, various methods to approach the electrical Indices are presented. In this research, the effect of pozzolanic materials fly ash (10%, 20% and 30% and silica fume (5% and 10% as substitute of cement by weight in binary and ternary mixtures on the fresh and hardened concrete properties were investigated. To determine mechanical properties, the compressive strength, splitting tensile strength and modulus of elasticity tests were performed. Also, water penetration depth, porosity, water sorptivity, specific electrical resistivity, rapid chloride penetration test (RCPT and rapid chloride migration test (RCMT tests were applied to evaluate concrete durability. To examine the border of aggregate and cement paste morphology of concrete specimens, scanning electron microscope images (SEM was used. The fresh concrete results showed that the presence of silica fume in binary and ternary mixtures reduced workability and air content but fly ash increased them. Adding silica fume to mixtures of containing flay ash while increasing mechanical strength reduced the porosity and pores to 18%. The presence of pozzolanic materials in addition to increasing bond quality and uniformity of aggregate-cement matrix border a considerably positive effect on the transport properties of concrete.

  3. Smog chamber study on the evolution of fume from residential coal combustion.

    Science.gov (United States)

    Geng, Chunmei; Wang, Kun; Wang, Wei; Chen, Jianhua; Liu, Xiaoyu; Liu, Hongjie

    2012-01-01

    Domestic coal stoves are widely used in countryside and greenbelt residents in China for heating and cooking, and emit considerable pollutants to the atmosphere because of no treatment of their exhaust, which can result in deteriorating local air quality. In this study, a dynamic smog chamber was used to investigate the real-time emissions of gaseous and particulate pollutants during the combustion process and a static smog chamber was used to investigate the fume evolution under simulate light irradiation. The real-time emissions revealed that the total hydrocarbon (THC) and CO increased sharply after ignition, and then quickly decreased, indicating volatilization of hydrocarbons with low molecular weight and incomplete combustion at the beginning stage of combustion made great contribution to these pollutants. There was evident shoulder peak around 10 min combustion for both THC and CO, revealing the emissions from vitrinite combustion. Additionally, another broad emission peak of CO after 30 min was also observed, which was ascribed to the incomplete combustion of the inertinite. Compared with THC and CO, there was only one emission peak for NOx, SO2 and particular matters at the beginning stage of combustion. The fume evolution with static chamber simulation indicated that evident consumption of SO2 and NOx as well as new particle formation were observed. The consumption rates for SO2 and NOx were about 3.44% hr(-1) and 3.68% hr(-1), the new particle formation of nuclei particles grew at a rate of 16.03 nm/hr during the first reaction hour, and the increase of the diameter of accumulation mode particles was evident. The addition of isoprene to the diluted mixture of the fume could promote 03 and secondary particle formation.

  4. Fuels planning: science synthesis and integration; environmental consequences fact sheet 12: Water Erosion Prediction Project (WEPP) Fuel Management (FuMe) tool

    Science.gov (United States)

    William Elliot; David Hall

    2005-01-01

    The Water Erosion Prediction Project (WEPP) Fuel Management (FuMe) tool was developed to estimate sediment generated by fuel management activities. WEPP FuMe estimates sediment generated for 12 fuel-related conditions from a single input. This fact sheet identifies the intended users and uses, required inputs, what the model does, and tells the user how to obtain the...

  5. Assessment of the Biological Effects of Welding Fumes Emitted From Metal Active Gas and Manual Metal Arc Welding in Humans.

    Science.gov (United States)

    Dewald, Eva; Gube, Monika; Baumann, Ralf; Bertram, Jens; Kossack, Veronika; Lenz, Klaus; Reisgen, Uwe; Kraus, Thomas; Brand, Peter

    2015-08-01

    Emissions from a particular welding process, metal inert gas brazing of zinc-coated steel, induce an increase in C-reactive protein. In this study, it was investigated whether inflammatory effects could also be observed for other welding procedures. Twelve male subjects were separately exposed to (1) manual metal arc welding fumes, (2) filtered air, and (3) metal active gas welding fumes for 6 hours. Inflammatory markers were measured in serum before, and directly, 1 and 7 days after exposure. Although C-reactive protein concentrations remained unchanged, neutrophil concentrations increased directly after exposure to manual metal arc welding fumes, and endothelin-1 concentrations increased directly and 24 hours after exposure. After exposure to metal active gas and filtered air, endothelin-1 concentrations decreased. The increase in the concentrations of neutrophils and endothelin-1 may characterize a subclinical inflammatory reaction, whereas the decrease of endothelin-1 may indicate stress reduction.

  6. [Investigation of urinary cadmium characteristics of the general population in three non-cadmium-polluted rural areas in China].

    Science.gov (United States)

    Han, Jingxiu; Hu, Ji; Sun, Hong; Jing, Qiqing; Wang, Xiaofeng; Lou, Xiaoming; Ding, Zhen; Chen, Xiaodong; Zhang, Wenli; Shang, Qi

    2014-11-01

    To investigate the characteristics of urinary cadmium of the non-occupational-cadmium-exposed population in non-cadmium contaminated rural area in China. Randomly selected non-occupational cadmium exposed population 2548 people (male 1290, female 1258) with each gender and age groups, questionnaire surveyed and collected random urine. Urinary cadmium and urinary creatinine (Cr) concentration were tested, excluding urinary Cr 3 g/L. Analyze the impact factors of urinary cadmium and calculated 95% quantile (P95) of urinary cadmium after correction by urinary Cr. Urinary cadmium increased with age and showed an upward trend. The urinary cadmium of the population of ≥ 30 years old was significantly higher than that of populations (China (GB Z17-2002). The urinary cadmium reference value of non-occupational-cadmium-exposed populations is China, but for smoking women over 30 year-old it needs more research to explore.

  7. 29 CFR 1926.1127 - Cadmium.

    Science.gov (United States)

    2010-07-01

    ... determination, and the name and social security number of each employee. (3) Monitoring frequency (periodic... cadmium; any history of renal, cardiovascular, respiratory, hematopoietic, reproductive, and/or musculo... future exposure to cadmium; smoking history and current status; reproductive history; current use of...

  8. REMOVAL OF CADMIUM FROM AQUEOUS SOLUTION USING ...

    African Journals Online (AJOL)

    The discharge of industrial effluents containing appreciably high concentrations of heavy metals such as zinc, cadmium, lead, ... synthesized products for the removal of cadmium ion from aqueous solution. This involves investigation ... manganese, and the charge is not compensated by the presence of other cation. Table 1.

  9. Association of urinary cadmium and myocardial infarction

    International Nuclear Information System (INIS)

    Everett, Charles J.; Frithsen, Ivar L.

    2008-01-01

    We conducted a cross-sectional analysis of individuals 45-79 years old in the National Health and Nutrition Examination Survey III (1988-1994) (NHANES III). Myocardial infarction was determined by electrocardiogram (ECG). Our sample included 4912 participants, which when weighted represented 52,234,055 Americans. We performed adjusted logistic regressions with the Framingham risk score, pack-years of smoking, race-ethnicity, and family history of heart attack, and diabetes as covariates. Urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.86 (95% CI 1.26-2.75) compared to urinary cadmium <0.43 μg/g creatinine. This result supports the hypothesis that cadmium is associated with coronary heart disease. When logistic regressions were done by gender, women, but not men, showed a significant association of urinary cadmium with myocardial infarction. Women with urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.80 (95% CI 1.06-3.04) compared to urinary cadmium <0.43 μg/g creatinine. When the analysis was restricted to never smokers (N=2187) urinary cadmium ≥0.88 μg/g creatinine had an odds ratio of 1.85 (95% CI 1.10-3.14) compared to urinary cadmium <0.43 μg/g creatinine

  10. Cadmium in the bioenergy system - a synthesis

    International Nuclear Information System (INIS)

    Ahlfont, K.

    1997-12-01

    Cadmium is a toxic metal without any known positive biological effects. Both emissions and atmospheric deposition of cadmium have decreased radically in Sweden during recent years. In Sweden, about 150 tonnes of cadmium was supplied to the technosphere in 1990, mostly originating from NiCd batteries. More than 100 tonnes of cadmium accumulated in the technosphere. Mankind takes up cadmium from water, food and particulate atmospheric pollution. Even small amounts may be injurious in the long-term since the half-life in the kidneys is 30 years. Cadmium in biofuel and ashes are generally a cause of discussion. Ashes from biofuel constitute a nutrient resource that should be returned to the soil. A possible risk with spreading ashes is the spreading of heavy metals, and then foremost cadmium, which is among the heavy metals that forest soils are considered to tolerate the least. Several studies on cadmium in the bioenergy system have been made, both within the Research Programme for Recycling of Wood-ash, and within Vattenfall's Bioenergy Project. The present report is intended to provide a picture of the current state of knowledge and to review plans for the future With a 3 page summary in English. 51 refs, 1 fig, 3 tabs

  11. Cadmium and children: Exposure and health effects.

    NARCIS (Netherlands)

    Schoeters, G.; Hond, E. Den; Zuurbier, M.; Naginiene, R.; Hazel, P.J. van den; Stilianakis, N.; Ronchetti, R.; Koppe, J.G.

    2006-01-01

    Cadmium exposure and accumulation in the body start at young age. Exposure routes in children are mainly via food, environmental tobacco smoke and house dust. Excretion from the body is limited. Cadmium accumulation in the kidney is responsible for effects such as nephrotoxicity and osteoporosis

  12. 29 CFR 1915.1027 - Cadmium.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Cadmium. 1915.1027 Section 1915.1027 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED... Cadmium. Note: The requirements applicable to shipyard employment under this section are identical to...

  13. Cadmium toxcity in the pregnant rat

    International Nuclear Information System (INIS)

    Martin, P.G.; Hitchcock, B.B.; King, J.F.

    1978-01-01

    Iron-deficient and normal pregnant rats were assigned to groups that either received a dose of cadmium (0.025, 0.050, or 0.100 mmole) plus 8 μCi of /sup 115m/Cd on day 18 of gestation or served as a nondosed group. Animals were either sacrificed 3 days after the dosing or allowed to litter (nondosed and 0.100 mmole cadmium groups only); pups and dams were sacrificed at 14 days of age. Viability of iron-deficient dams and fetuses and pups from iron-deficient dams was affected by the 0.100 mmole cadmium dose to a greater degree than was that in comparable normal animals. Although calculated amounts of cadmium deposited in the dam's liver, kidney, blood, tibia, and fetuses were greater in iron-deficient than in normal animals at all doses, differences were not significant except in the amount of cadmium accumulated in the placenta at the highest cadmium doses. Total deposition in the placentas/litter was similar for normal and iron-deficient groups at each dose level. The decreased viability may have been due to the dam's decreased food intake; blockage of nutrients, especially minerals, by cadmium--protein complexes in the placenta; or hormonal interruptions of pregnancy by steroid--cadmium complexes

  14. Zone refining of cadmium and related characterization

    Indian Academy of Sciences (India)

    We present the zone refining results of cadmium using horizontal resistive zone refiner under constant flow of moisture free hydrogen gas. The boron impurity in cadmium can be avoided using quartz (GE 214 grade) boat in lieu of high pure graphite boat. The analytical results using inductively coupled plasma optical ...

  15. Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes.

    Science.gov (United States)

    Aberare, Ogbevire L; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

    2011-06-01

    Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Twenty-five Wister albino rats (of both sexes) were used for this study between the 4(th) of August and 7(th) of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (Plevel of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. These results showed that frequent exposure to petrol fumes may be highly deleterious to the liver cells.

  16. Novel Cadmium Resistance Determinant in Listeria monocytogenes.

    Science.gov (United States)

    Parsons, Cameron; Lee, Sangmi; Jayeola, Victor; Kathariou, Sophia

    2017-03-01

    Listeria monocytogenes is a foodborne pathogen that can cause severe disease (listeriosis) in susceptible individuals. It is ubiquitous in the environment and often exhibits resistance to heavy metals. One of the determinants that enables Listeria to tolerate exposure to cadmium is the cadAC efflux system, with CadA being a P-type ATPase. Three different cadA genes (designated cadA1 to cadA3 ) were previously characterized in L. monocytogenes A novel putative cadmium resistance gene ( cadA4 ) was recently identified through whole-genome sequencing, but experimental confirmation for its involvement in cadmium resistance is lacking. In this study, we characterized cadA4 in L. monocytogenes strain F8027, a cadmium-resistant strain of serotype 4b. By screening a mariner-based transposon library of this strain, we identified a mutant with reduced tolerance to cadmium and that harbored a single transposon insertion in cadA4 The tolerance to cadmium was restored by genetic complementation with the cadmium resistance cassette ( cadA4C ), and enhanced cadmium tolerance was conferred to two unrelated cadmium-sensitive strains via heterologous complementation with cadA4C Cadmium exposure induced cadA4 expression, even at noninhibitory levels. Virulence assessments in the Galleria mellonella model suggested that a functional cadA4 suppressed virulence, potentially promoting commensal colonization of the insect larvae. Biofilm assays suggested that cadA4 inactivation reduced biofilm formation. These data not only confirm cadA4 as a novel cadmium resistance determinant in L. monocytogenes but also provide evidence for roles in virulence and biofilm formation. IMPORTANCE Listeria monocytogenes is an intracellular foodborne pathogen causing the disease listeriosis, which is responsible for numerous hospitalizations and deaths every year. Among the adaptations that enable the survival of Listeria in the environment are the abilities to persist in biofilms, grow in the cold, and

  17. Exposure to welding fumes activates DNA damage response and redox-sensitive transcription factor signalling in Sprague-Dawley rats.

    Science.gov (United States)

    Krishnaraj, Jayaraman; Kowshik, Jaganathan; Sebastian, Robin; Raghavan, Sathees C; Nagini, Siddavaram

    2017-05-15

    Occupational exposure to welding fumes containing a complex mixture of genotoxic heavy metals, radiation, gases and nanoparticles poses a serious health hazard to welders. Since their categorization as possible carcinogens, welding fumes have gained increasing attention as high priority agents for risk assessment. The present study was undertaken to investigate the effects of welding fume inhalation on oxidative stress, DNA damage response (DDR), and nuclear factor erythroid 2-related factor-2 (Nrf2) and nuclear factor kappa B (NFκB) signalling in the lung tissues of male Sprague-Dawley rats . METHODS: Animals were divided into five groups. Group 1 animals served as control. Rats in groups 2-5 were exposed to 50mg/m 3 stainless steel (SS) welding fumes for 1h for 1day, 1 week, 2 weeks, and 4 weeks respectively. Reactive oxygen species (ROS) generation, 8-oxo-2'-deoxyguanosine (8-oxodG), xenobiotic-metabolizing enzymes (XMEs) and antioxidants were analysed. DNA damage sensors, DNA repair enzymes, inflammatory mediators, cell cycle progression, apoptosis and key players in Nrf2 and NFκB signalling were assessed by flow cytometry, quantitative real-time reverse transcriptase PCR, immunoblotting, immunohistochemistry and immunofluorescence. Rats exposed to welding fumes showed increased levels of chromium and ROS in lung tissues associated with accumulation of 8-oxodG and enhanced expression of XMEs and antioxidants. This was accompanied by upregulation of DNA damage sensors, cell cycle arrest in G1/S phase, overexpression of a multitude of DNA repair enzymes and caspase-mediated apoptosis. In addition, exposure to welding fumes induced activation of Nrf2 and NFκB signalling with enhanced expression of inflammatory mediators. The results of the present study unequivocally demonstrate that exposure of rats to SS welding fumes alters the expression of 37 genes involved in oxidative stress, detoxification, inflammation, DNA repair, cell cycle progression, and apoptosis

  18. Molecular and cellular mechanisms of cadmium carcinogenesis

    International Nuclear Information System (INIS)

    Waisberg, Michael; Joseph, Pius; Hale, Beverley; Beyersmann, Detmar

    2003-01-01

    Cadmium is a heavy metal, which is widely used in industry, affecting human health through occupational and environmental exposure. In mammals, it exerts multiple toxic effects and has been classified as a human carcinogen by the International Agency for Research on Cancer. Cadmium affects cell proliferation, differentiation, apoptosis and other cellular activities. Cd 2+ does not catalyze Fenton-type reactions because it does not accept or donate electrons under physiological conditions, and it is only weakly genotoxic. Hence, indirect mechanisms are implicated in the carcinogenicity of cadmium. In this review multiple mechanisms are discussed, such as modulation of gene expression and signal transduction, interference with enzymes of the cellular antioxidant system and generation of reactive oxygen species (ROS), inhibition of DNA repair and DNA methylation, role in apoptosis and disruption of E-cadherin-mediated cell-cell adhesion. Cadmium affects both gene transcription and translation. The major mechanisms of gene induction by cadmium known so far are modulation of cellular signal transduction pathways by enhancement of protein phosphorylation and activation of transcription and translation factors. Cadmium interferes with antioxidant defense mechanisms and stimulates the production of reactive oxygen species, which may act as signaling molecules in the induction of gene expression and apoptosis. The inhibition of DNA repair processes by cadmium represents a mechanism by which cadmium enhances the genotoxicity of other agents and may contribute to the tumor initiation by this metal. The disruption of E-cadherin-mediated cell-cell adhesion by cadmium probably further stimulates the development of tumors. It becomes clear that there exist multiple mechanisms which contribute to the carcinogenicity of cadmium, although the relative weights of these contributions are difficult to estimate

  19. Cadmium mobility and accumulation in soils of the European Communities

    NARCIS (Netherlands)

    Fraters B; van Beurden AUCJ

    1993-01-01

    In this overview of the effects of cadmium pollution on agricultural soils in the European Community, both the cadmium loads on agricultural land and the soil sensitivity to cadmium accumulation have been estimated. Cadmium loads have been estimated separately for arable land and grassland. The

  20. Collective acute poisoning by nitrous gases

    Energy Technology Data Exchange (ETDEWEB)

    Touze, M.D.; Desjars, P.; Baron, D.; Tasseau, F.; Delajartre, A.Y.; Nicolas, F.

    1983-09-01

    A collective nitrous fumes poisoning (five cases) is reported. Two patients (case 3 and case 4) were comatose, in severe respiratory distress. Shock and slate blue cyanosis were noted. Physical examination and chest X ray revealed acute pulmonary edema-Methemoglobin levels were 71,3% (case 3) and 58% (case 4). Despite treatment both of them died from severe hypoxia resulting in cardiorespiratory arrest. Post-mortem examination was performed upon these four men. On admission the last one (case 5) was conscious, and in good hemodynamic condition. Acute pulmonary edema and cyanosis were present. Methemoglobin level was 37,3%. This patient recovered appropriate therapy. For case 1 and 2 acute anoxia due to methemoglobinemia seems to be cause of death. For cases 3 and 4 death is due to hypoxemia associated with pulmonary edema.

  1. Association of lead and cadmium exposure with frailty in US older adults

    International Nuclear Information System (INIS)

    García-Esquinas, Esther; Navas-Acien, Ana; Pérez-Gómez, Beatriz; Artalejo, Fernando Rodríguez

    2015-01-01

    Background: Environmental lead and cadmium exposure is associated with higher risk of several age-related chronic diseases, including cardiovascular disease, chronic kidney disease and osteoporosis. These diseases may lead to frailty, a geriatric syndrome characterized by diminished physiologic reserve in multiple systems with decreased ability to cope with acute stressors. However, no previous study has evaluated the association between lead or cadmium exposure and frailty. Methods: Cross-sectional study among individuals aged ≥60 years who participated in the third U.S. National Health and Nutrition Examination Survey and had either blood lead (N=5272) or urine cadmium (N=4887) determinations. Frailty was ascertained with a slight modification of the Fried criteria, so that individuals meeting ≥3 of 5 pre-defined criteria (exhaustion, low body weight, low physical activity, weakness and slow walking speed), were considered as frail. The association between lead and cadmium with frailty was evaluated using logistic regression with adjustment for relevant confounders. Results: Median (intertertile range) concentrations of blood lead and urine cadmium were 3.9 µg/dl (2.9–4.9) and 0.62 µg/l (0.41–0.91), respectively. The prevalence of frailty was 7.1%. The adjusted odds ratios (95% confidence interval) of frailty comparing the second and third to the lowest tertile of blood lead were, respectively, 1.40 (0.96–2.04) and 1.75 (1.33–2.31). Lead concentrations were also associated with the frequency of exhaustion, weakness and slowness. The corresponding odds ratios (95% confidence interval) for cadmium were, respectively, 0.97 (0.68–1.39) and 1.55 (1.03–2.32), but this association did not hold after excluding participants with reduced glomerular filtration rate: 0.70 (0.43–1.14) and 1.09 (0.56–2.11), respectively. Conclusions: In the US older adult population, blood lead but not urine cadmium concentrations showed a direct dose

  2. Association of lead and cadmium exposure with frailty in US older adults

    Energy Technology Data Exchange (ETDEWEB)

    García-Esquinas, Esther, E-mail: esthergge@gmail.com [Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autónoma de Madrid/ IdiPAZ, Madrid (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Navas-Acien, Ana [Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD (United States); Pérez-Gómez, Beatriz [CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Environmental Epidemiology and Cancer Unit, National Center for Epidemiology, Carlos III Institute of Health, Madrid (Spain); Artalejo, Fernando Rodríguez [Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autónoma de Madrid/ IdiPAZ, Madrid (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain)

    2015-02-15

    Background: Environmental lead and cadmium exposure is associated with higher risk of several age-related chronic diseases, including cardiovascular disease, chronic kidney disease and osteoporosis. These diseases may lead to frailty, a geriatric syndrome characterized by diminished physiologic reserve in multiple systems with decreased ability to cope with acute stressors. However, no previous study has evaluated the association between lead or cadmium exposure and frailty. Methods: Cross-sectional study among individuals aged ≥60 years who participated in the third U.S. National Health and Nutrition Examination Survey and had either blood lead (N=5272) or urine cadmium (N=4887) determinations. Frailty was ascertained with a slight modification of the Fried criteria, so that individuals meeting ≥3 of 5 pre-defined criteria (exhaustion, low body weight, low physical activity, weakness and slow walking speed), were considered as frail. The association between lead and cadmium with frailty was evaluated using logistic regression with adjustment for relevant confounders. Results: Median (intertertile range) concentrations of blood lead and urine cadmium were 3.9 µg/dl (2.9–4.9) and 0.62 µg/l (0.41–0.91), respectively. The prevalence of frailty was 7.1%. The adjusted odds ratios (95% confidence interval) of frailty comparing the second and third to the lowest tertile of blood lead were, respectively, 1.40 (0.96–2.04) and 1.75 (1.33–2.31). Lead concentrations were also associated with the frequency of exhaustion, weakness and slowness. The corresponding odds ratios (95% confidence interval) for cadmium were, respectively, 0.97 (0.68–1.39) and 1.55 (1.03–2.32), but this association did not hold after excluding participants with reduced glomerular filtration rate: 0.70 (0.43–1.14) and 1.09 (0.56–2.11), respectively. Conclusions: In the US older adult population, blood lead but not urine cadmium concentrations showed a direct dose

  3. Comparative proteome analysis of high and low cadmium accumulating soybeans under cadmium stress.

    Science.gov (United States)

    Hossain, Zahed; Hajika, Makita; Komatsu, Setsuko

    2012-12-01

    A comparative proteomic study was performed to unravel the protein networks involved in cadmium stress response in soybean. Ten-day-old seedlings of contrasting cadmium accumulating soybean cultivars-Harosoy (high cadmium accumulator), Fukuyutaka (low cadmium accumulator), and their recombinant inbred line CDH-80 (high cadmium accumulator) were exposed to 100 μM CdCl(2) treatment for 3 days. Root growth was found to be affected under cadmium stress in all. Varietal differences at root protein level were evaluated. NADP-dependent alkenal double bond reductase P1 was found to be more abundant in low cadmium accumulating Fukuyutaka. Leaf proteome analysis revealed that differentially expressed proteins were primarily involved in metabolism and energy production. The results indicate that both high and low cadmium accumulating cultivars and CDH-80 share some common defense strategies to cope with the cadmium stress. High abundance of enzymes involved in glycolysis and TCA cycle might help cadmium challenged cells to produce more energy necessary to meet the high energy demand. Moreover, enhanced expressions of photosynthesis related proteins indicate quick utilization of photoassimilates in energy generation. Increased abundance of glutamine synthetase in all might be involved in phytochelatin mediated detoxification of cadmium ions. In addition, increased abundance of antioxidant enzymes, namely superoxide dismutase, ascorbate peroxidase, catalase, ensures cellular protection from reactive oxygen species mediated damages under cadmium stress. Enhanced expression of molecular chaperones in high cadmium accumulating cultivar might be another additional defense mechanism for refolding of misfolded proteins and to stabilize protein structure and function, thus maintain cellular homeostasis.

  4. Use of cadmium telluride solar cells and environmental aspects

    International Nuclear Information System (INIS)

    Karus, M.; Wittassek, R.; Linden, W.

    1990-05-01

    Cadmium telluride solar cells for power generation may give rise to environmental pollution with cadmium in the event of incidents during fabrication, fires during operation or inappropriate disposal after use. Fires may liberate more than 50% of cadmium contained; disposal at municipal landfills and sufficient contact with water may even release 100% of cadmium. According to the waste disposal regulations in force, cadmium telluride cells, because of their cadmium content and the high risk of cadmium liberation on contact with water, must be disposed of in underground storages of category six. (orig.) [de

  5. Occupational exposure to asphalt fume can cause oxidative DNA damage among road paving workers.

    Science.gov (United States)

    Bal, Ceylan; Ağış, Erol R; Büyükşekerci, Murat; Gündüzöz, Meşide; Tutkun, Lütfiye; Yılmaz, Ömer H

    2018-03-07

    We designed the present study to determine the effect of occupational exposure to asphalt fumes on oxidative status and DNA damage in road paving workers. Sixty road paving workers exposed to asphalt fumes and forty non-exposed control subjects were recruited. Occupational exposure to PAHs was assessed by urinary 1-hydroxypyrene (1-OHP) excretion. Serum thiol disulfide homeostasis (TDH), total oxidant status (TOS) and total antioxidant status (TAS) and urinary 8-hydro-deoxyguanosine (8-OH-dG) level were evaluated by automated colourimetric method. The urinary concentrations of 1-OHP and 8-OH-dG were significantly higher in the exposed group than in the control group (P < 0.001). Disulfide/thiol ratio, TOS, and TAS were also significantly higher for the asphalt workers. A positive correlation existed between urinary 1-OHP and 8-OH-dG, TOS and TAS. Study results indicate that exposure to PAHs induces oxidative stress and causes genotoxic effects in asphalt workers. © 2018 Wiley Periodicals, Inc.

  6. Manganese in exhaled breath condensate: a new marker of exposure to welding fumes.

    Science.gov (United States)

    Hulo, Sébastien; Chérot-Kornobis, Nathalie; Howsam, Mike; Crucq, Sébastien; de Broucker, Virginie; Sobaszek, Annie; Edme, Jean-Louis

    2014-04-07

    To evaluate manganese in exhaled breath condensate (Mn-EBC) as an indicator of exposure to fumes from metal inert gas welding process. We collected EBC and urine from 17 welders and 16 unexposed control subjects after 5 days exposure. Concentrations of manganese (Mn), nickel (Ni), iron (Fe) and chromium (Cr) were measured in EBC and urine samples and correlated with cumulative exposure indices for the working week (CIW) and for the total welding years (WY), based on duration of welding activity and atmospheric metal measurements. Concentrations of Mn and Ni in EBC were significantly higher among welders than controls whereas this difference was not significant for Mn in urine. Levels of Mn and Ni in EBC were not correlated with their respective levels in urine. The linear regressions found significant positive coefficients between Mn-EBC, Ni-EBC, Ni-U and Cr-U concentrations and the cumulative exposure indices. Taking into account tobacco use, statistical analysis showed the same trends except for the relationship between Mn-U and CIW. This pilot study showed that Mn-EBC, as well as Ni-EBC, can serve as reliable indices of occupational exposure to welding fumes and provide complimentary toxicokinetic information to that provided by urine analyses. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Lipase immobilization for catalytic applications obtained using fumed silica deposited with MAPLE technique

    Science.gov (United States)

    Bloisi, Francesco; Califano, Valeria; Perretta, Giuseppe; Nasti, Libera; Aronne, Antonio; Di Girolamo, Rocco; Auriemma, Finizia; De Rosa, Claudio; Vicari, Luciano R. M.

    2016-06-01

    Lipases are enzymes used for catalyzing reactions of acylglycerides in biodiesel production from lipids, where enzyme immobilization on a substrate is required. Silica nanoparticles in different morphologies and configurations are currently used in conjunction with biological molecules for drug delivery and catalysis applications, but up to date their use for triglycerides has been limited by the large size of long-chain lipid molecules. Matrix assisted pulsed laser evaporation (MAPLE), a laser deposition technique using a frozen solution/suspension as a target, is widely used for deposition of biomaterials and other delicate molecules. We have carried out a MAPLE deposition starting from a frozen mixture containing fumed silica and lipase in water. Deposition parameters were chosen in order to increase surface roughness and to promote the formation of complex structures. Both the target (a frozen thickened mixture of nanoparticles/catalyst in water) and the deposition configuration (a small target to substrate distance) are unusual and have been adopted in order to increase surface contact of catalyst and to facilitate access to long-chain molecules. The resulting innovative film morphology (fumed silica/lipase cluster level aggregation) and the lipase functionality (for catalytic biodiesel production) have been studied by FESEM, FTIR and transesterification tests.

  8. Exposure of Petrol Station Attendants and Auto Mechanics to Premium Motor Sprit Fumes in Calabar, Nigeria

    Directory of Open Access Journals (Sweden)

    N. E. Udonwa

    2009-01-01

    Full Text Available A population-based-cross-sectional survey was carried out to investigate the potential risk of exposure to premium motor spirit (PMS fumes in Calabar, Nigeria, among Automobile Mechanics (AM, Petrol Station Attendants (PSA and the general population. Structured questionnaire was administered on the randomly chosen subjects to elicit information on their exposure to PMS. Duration of exposure was taken as the length of work in their various occupations. Venous blood was taken for methaemoglobin (MetHb and packed cells volume (PCV. Mean MetHb value was higher in AM (7.3% and PSA (5.8% than in the subjects from the general population (2.7%. PCV was lower in PSA (30.8%, than AM (33.3% and the subjects from the general population (40.8%. MetHb level was directly proportional, and PCV inversely related, to the duration of exposure. The study suggested increased exposure to petrol fumes among AM, PSA, and MetHb as a useful biomarker in determining the level of exposure to benzene in petrol vapour.

  9. Green binding material using alkali activated blast furnace slag with silica fume

    Directory of Open Access Journals (Sweden)

    Mohamad Sayed

    2012-12-01

    Full Text Available Recently million tons of cement is produced in Egypt accompanied with million tons of CO2 emission which causes annually negative impact on the environment. Granulated blast furnace slag and silica fume are produced as by-product from iron and chemical industries with limited recycling facility. This paper represents an experimental study aimed to safe ferrosilicon alloy of slag and silica fume to produce cementless binding material using both of Sodium Hydroxide and water glass liquid (Sodium Silicate as alkaline activator. Experimental program was designed to study silica/slag ratio, percentage of alkali activator, water/binding ratio, incorporation of superplasticizer, and curing condition on the properties of the produced binding material. Compressive strength and mineralogical analysis were conducted on the polymeric binding material to asses the effectiveness of the main variables. The tests were divided into two stages; in the first stage compressive strength was conducted for all mixes while X-ray, microscopic scan (SEM, and infrared analysis (IR were carried out for the most pronounced promising mixes. The results showed that ratio of 25% of silica/slag is the most effective ratio and 5% of each of Sodium Hydroxide and Sodium Silicate was the optimum percentage of the alkaline activator. Additionally the use of superplasticizer is essential as it positively reduces the mixing water and maintains the binding material with acceptable workability.

  10. Physico-mechanical properties of high performance concrete using different aggregates in presence of silica fume

    Directory of Open Access Journals (Sweden)

    Salah A. Abo-El-Enein

    2014-04-01

    Full Text Available Heavy weight high performance concrete (HPC can be used when particular properties, such as high strength and good radiation shielding are required. Such concrete, using ilmenite and hematite coarse aggregates can significantly have higher specific gravities than those of concrete made with dolomite and air-cooled slag aggregates. Four different concrete mixes with the same cement content and different w/c ratios were designed using normal dolomite aggregate, air-cooled slag by-product and two different types of iron ore aggregates. High performance concrete (grade-M60 can be achieved using superplasticizer to reduce the water/cement ratio; the effect of SF on the performance of concrete was studied by addition of 10% silica fume to the total cement content. The physico-mechanical properties of coarse aggregates and hardened concrete were studied. The results show that, Ilmenite coarse aggregate gives higher physical and mechanical properties than the other aggregates. Also, addition of 10% silica fume developed a stronger and a denser interfacial transition zone (ITZ between concrete particles and the cement matrix. Crushed air-cooled slag can be used to produce a high-strength concrete with better mechanical properties than corresponding concrete made with crushed hematite and ilmenite. Heavy density concrete made with fine aggregates of ilmenite and air-cooled slag are expected to be suitable as shielding materials to attenuate gamma rays.

  11. Numerical analysis of the influence of particle charging on the fume formation process in arc welding

    International Nuclear Information System (INIS)

    Tashiro, Shinichi; Matsui, Sho; Tanaka, Manabu; Murphy, Anthony B

    2013-01-01

    In order to clarify the influence of electrostatic forces caused by charging of particles on the coagulation process in fume formation in arc welding, a previously developed fume formation model is modified to consider the influence of charging, for both local thermodynamic equilibrium (LTE) and non-LTE conditions. The model takes into account formation of the particles from metal vapour by nucleation, growth of the particles by condensation of metal vapour and coagulation of the particles by collisions to form secondary particles. Results are obtained for both ballistic and Brownian motion of the particles. It is found that the growth of secondary particles is suppressed when the average particle charge becomes significant, because charging of the particle hinders collisions among secondary particles through the strong repulsive electrostatic force. Furthermore, deviations from LTE strongly affect the coagulation process, because the increased electron density at a given gas temperature increases the charging of particles. Brownian motion leads to larger secondary particles, since the average particle speed is increased. The influence of Brownian motion and particle charging cancel each other to a large extent, particularly when deviations from LTE are considered. (paper)

  12. Spinning, drawing and physical properties of polypropylene nanocomposite fibers with fumed nanosilica

    Directory of Open Access Journals (Sweden)

    I. Dabrowska

    2015-03-01

    Full Text Available Nanocomposite fibers of isotactic polypropylene – fumed silica AR805 were prepared by melt compounding using a two-step process: melt-spinning and hot drawing at various draw ratios up to 15. Transmission electron microscopy revealed uniform dispersion of the silica nanoparticles in polypropylene matrix, although at higher concentrations and lower draw ratios the nanoparticles showed increasing tendency to form small agglomerates. On the other hand, at low concentrations the uniform distribution of fumed silica improved mechanical properties of the composite fibers, especially at higher draw ratios. Crystallinity and melting temperature of fibers were found to significantly increase after drawing. Elastic modulus at draw ratio = 10 rose from 5.3 GPa for neat PP up to 6.2–8.1 GPa for compositions in the range 0.25–2 vol% of the filler. Moreover, higher tensile strength and creep resistance were achieved, while strain at break was rather insensitive to the filler fraction. Considering all experimental results, a failure model was proposed to explain the toughness improvement during the drawing process by the induced orientation of polymer chains and the formation of voids.

  13. Effect of containing silica fume on cytotoxicity of white mineral trioxide aggregate.

    Science.gov (United States)

    Pirzadeh-Ashraf, Ahmad; Lotfi, Mehrdad; Zarandi, Ali; Yazdani, Ebrahim; Mozafari, Aysan; Pornasrollah, Alireza

    2018-01-01

    Mineral trioxide aggregate (MTA) has a high biocompatibility and its physical properties could be improved by adding the containing silica fume an amorphous silicon dioxide (condensed silica fume [CSF]). The aim of this study was to evaluate the cytotoxicity of MTA mixed with CSF on the viability of L929 mouse fibroblast cell using 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide reduction assay (MTT assay). In this in vitro study white MTA was mixed with distilled water according to the manufacturer's instructions. Mixtures of White MTA with 10%, 15%, and 20% CSF by weight were prepared and mixed with distilled water. Cytotoxicity of mixtures was compared with MTT assay on L929 mouse fibroblast cell line after 24, 48, and 72 h. Differences in cytotoxicity were assessed by one-way analysis of variance (ANOVA). Mean ± SD of vital cell counts cultured in MTA, MTA + 10% CSF, MTA + 15% CSF, and MTA + 20% CSF were 98% ± 6%, 97% ± 6%, 94% ± 4%, and 98% ± 4%, respectively. One-way ANOVA did not reveal any statistically significant difference between the groups ( P > 0.05). It may be concluded that addition of CSF to MTA may not influence its cytotoxicity.

  14. 1-Hydroxypyrene Levels in Blood Samples of Rats After Exposure to Generator Fumes

    Science.gov (United States)

    Ifegwu, Clinton; Igwo-Ezikpe, Miriam N.; Anyakora, Chimezie; Osuntoki, Akinniyi; Oseni, Kafayat A.; Alao, Eragbae O.

    2013-01-01

    Polynuclear Aromatic Hydrocarbons (PAHs) are a major component of fuel generator fumes. Carcinogenicity of these compounds has long been established. In this study, 37 Swiss albino rats were exposed to generator fumes at varied distances for 8 hours per day for a period of 42 days and the level of 1-hydroxypyrene in their blood was evaluated. This study also tried to correlate the level of blood 1-hyroxypyrene with the distance from the source of pollution. Plasma was collected by centrifuging the whole blood sample followed by complete hydrolysis of the conjugated 1-hydroxypyrene glucuronide to yield the analyte of interest, 1-hydroxypyrene, which was achieved using beta glucuronidase. High performance liquid chromatography (HPLC) with UV detector was used to determine the 1-hydroxypyrene concentrations in the blood samples. The mobile phase was water:methanol (12:88 v/v) isocratic run at the flow rate of 1.2 mL/min with CI8 stationary phase at 250 nm. After 42 days of exposure, blood concentration level of 1-hydroxypyrene ranged from 34 μg/mL to 26.29 μg/mL depending on the distance from source of exposure. The control group had no 1-hydroxypyrene in their blood. After the period of exposure, percentage of death correlated with the distance from the source of exposure. Percentage of death ranged from 56% to zero depending on the proximity to source of pollution. PMID:24179393

  15. Toenail as Non-invasive Biomarker in Metal Toxicity Measurement of Welding Fumes Exposure - A Review

    Science.gov (United States)

    Bakri, S. F. Z.; Hariri, A.; Ma'arop, N. F.; Hussin, N. S. A. W.

    2017-01-01

    Workers are exposed to a variety of heavy metal pollutants that are released into the environment as a consequence of workplace activities. This chemical pollutants are incorporated into the human by varies of routes entry and can then be stored and distributed in different tissues, consequently have a potential to lead an adverse health effects and/or diseases. As to minimize the impact, a control measures should be taken to avoid these effects and human biological marker is a very effective tool in the assessment of occupational exposure and potential related risk as the results is normally accurate and reproducible. Toenail is the ideal matrix for most common heavy metals due to its reliability and practicality compared to other biological samples as well as it is a non-invasive and this appears as a huge advantage of toenail as a biomarker. This paper reviews studies that measure the heavy metals concentration in toenail as non-invasive matrix which later may adapt in the investigation of metal fume emitted from welding process. The development of new methodology and modern analytical techniques has allowed the use of toenail as non-invasive approach. The presence of a heavy metal in this matrix reflects an exposure but the correlations between heavy metal levels in the toenail must be established to ensure that these levels are related to the total body burden. These findings suggest that further studies on interactions of these heavy metals in metal fumes utilizing toenail biomarker endpoints are highly warranted especially among welders.

  16. Experiment to decipher the effect of heavy metal cadmium on coastal benthic foraminifer Pararotalia Nipponica (Asano)

    Digital Repository Service at National Institute of Oceanography (India)

    Linshy, V.N.; Saraswat, R.; Kurtarkar, S.R.; Nigam, R.

    health hazards including kidney damage (Jarup et al., 1998; Bernard, 2004), bone damage (Kazantzis, 2004), acute respiratory diseases (Barbee and Prince, 1999), gastro-intestinal problems (Nordberg, 2004) and even cancer in humans (Il'yasova, 2005... and Environmentsl Safety, 7: 9–24. Il'yasova, D. S.G.G. 2005. Cadmium and renal cancer. Toxicology and Applied Pharmacology, 207, 179-186. IOSHIC. 1999 International occupational safety and health information centre. Metals in basics of chemical safety, chapter...

  17. Absorption and tissue distribution of cadmium in mice after chronic feeding with cadmium chloride and cadmium-methallothionein

    International Nuclear Information System (INIS)

    Cherian, M.G.

    1983-01-01

    Mice were fed 20 μg cadmium chloride (CdCl 2 ) and cadmium-methallothionein (CdMt) once a week for 5 weeks using Cd-109 as a tracer. Body burden measurements suggest that the levels in tissues drop after the third week when CdMt is the source, but continue to increase with CdCl 2 . Tissue distribution is tabulated as % retained cadmium for various organs tested. Major sites of accumulations are the liver, kidneys, pancreas, and gastrointestinal tract

  18. Cadmium Exposure is Associated with the Prevalence of Dyslipidemia.

    Science.gov (United States)

    Zhou, Zhou; Lu, Yong-Hui; Pi, Hui-Feng; Gao, Peng; Li, Min; Zhang, Lei; Pei, Li-Ping; Mei, Xiang; Liu, Lin; Zhao, Qi; Qin, Qi-Zhong; Chen, Yu; Jiang, Yue-Ming; Zhang, Zhao-Hui; Yu, Zheng-Ping

    2016-01-01

    Cadmium is a widespread environmental and occupational pollutant that accumulates in human body with a biological half-life exceeding 10 years. Cadmium exposure has been demonstrated to increase rates of cardiovascular diseases. Whether occupational cadmium exposure is associated with the increase in the prevalence of dyslipidemia and hence contributes to the risk of cardiovascular diseases is still equivocal. To test the hypothesis that exposure to cadmium is related to the prevalence of dyslipidemia, we examined the associations between blood cadmium concentration and the prevalence of dyslipidemia in workers occupationally exposed to cadmium in China. A cross-sectional survey on demographic data, blood cadmium level and lipid profile in cadmium exposed workers from seven cadmium smelting factories in central and southwestern China was conducted. We measured blood cadmium concentration and lipid components of 1489 cadmium exposed workers. The prevalence of dyslipidemia was compared across blood cadmium quartiles. Associations between the blood cadmium concentrations and the prevalence of dyslipidemia were assessed using confounder adjusted linear and logistic regressions. The blood cadmium concentration was 3.61±0.84µg/L ( mean ±SD). The prevalence of dyslipidemia in this occupational population was 66.3%. Mean blood cadmium concentration of workers with dyslipedemia was significantly higher than that of workers without dyslipidemia (p dyslipidemia increased dose-dependently with elevations in blood cadmium concentrations (p for trend dyslipidemia across the increasing blood cadmium quartiles were 1.21(1.16-1.55), 1.56(1.11-1.87), 1.79(1.26-2.25) respectively (referencing to 1.00; p for trend dyslipidemia remained unchanged (all p for trend dyslipidemia. Cadmium exposure could alter lipid metabolism in humans. It is imperative to control cadmium exposure of occupational population in cadmium related industries and reduce adverse health effects. © 2016 The

  19. Radiochemical separation of cadmium-109

    International Nuclear Information System (INIS)

    Egamediev, S.; Mukhtarov, A.; Nurbaeva, D.; Rakhmanov, A.

    2006-01-01

    Full text: Cadmium-109 has a half-life of 461.9 days and decays by electron capture to 109 Ag with the emission of 88 keV γ-ray (3.79%) along with the characteristic X-ray from the K level of Ag, with energy of 22.5 keV. This radionuclide has found widespread use as a photon source in x-ray fluorescence analysis devices employed in industry for numerous applications such as the direct determination of gold in ores, the analysis of metals and identification of steels. Other applications range from its use as an electron source for measurement of densities of air-pollution samples, to tracer studies in mushrooms and mice and rats. In the nuclear medicine field there is growing interest in employing 109 Cd in a 109 Cd/ 109mA g generator, as an alternative to other biomedical generators of ultra short-lived gamma emitters. There are several methods for the production of 109 Cd in literature: 1. Bombardment of silver cyclotron target via 109 Ag(d,2n) 109 Cd reaction with 16 MeV deuterons. 2. Bombardment of natural silver target via 109 Ag(p,n) 109 Cd reaction with 14 MeV protons. 3. Proton bombardment of natural indium target with 96 MeV protons. 4. Irradiation of enriched 107 Ag target in high-flux nuclear reactor at neutron flux 2x10 15 n·cm -2 ·s -1 via 107 Ag(n,γ) 108 Ag → 108 Cd (n,γ) 109 Cd reaction. 5. Irradiation of enriched 108 Cd target in nuclear reactor at neutron flux 1x10 14 n·cm -2 ·s -1 via 108 Cd (n,γ) 109 Cd reaction. The production of 109 Cd with proton beam via 109 Ag(p,n) 109 Cd reaction is ideal for the cyclotron U-150, since it is not required the change of the regime for the machine functioning. Because of its relatively long half-life the time required for separation is also not an important factor, but its use as an X-ray source requires a very high radiochemical purity. In the present work we studied two methods for separation of 109 Cd from model solution of silver targets. First method is based on precipitation of silver as

  20. Response of Saccharomyces cerevisiae to cadmium stress

    International Nuclear Information System (INIS)

    Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C.; Rosa, Carlos Augusto

    2009-01-01

    The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K + and Na + ) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

  1. Response of Saccharomyces cerevisiae to cadmium stress

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia], e-mail: luamatu@uol.com.br; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Lab. de Ativacao Neutronica], e-mail: menezes@cdtn.br; Rosa, Carlos Augusto [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Microbiologia], e-mail: carlrosa@icb.ufmg

    2009-07-01

    The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K{sup +} and Na{sup +}) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

  2. Cadmium decontamination using in-house resin

    International Nuclear Information System (INIS)

    Pal, Sangita; Thalor, K.L; Prabhakar, S.; Srivastava, V.K.; Goswami, J.L.; Tewari, P.K.; Dhanpal, Pranav; Goswami, J.L.

    2010-01-01

    A selective and strong in-house chelator has been studied w.r.t. basic parameters like concentration, time, and elution. De-contamination of cadmium, mercury, chromium, lead etc by using high uptake values fro cadmium ions proves its selectivity with high elution ratio ensures further decontamination of run-off water during natural calamities. In three step cascade use the concentration of original cadmium solution (500 ppm) decocted to safe disposable attribute. This polymeric ligand exchanger displayed outlet effluent concentration to 1 ppm and less than 200 ppb when treated for inlet feed concentration of 50 ppm and 500 ppm respectively. (author)

  3. Cadmium electrode and process for its production

    Energy Technology Data Exchange (ETDEWEB)

    Rampel, G.G.; Puglisi, V.J.

    1991-11-12

    This patent describes a cadmium electrode for use in a rechargeable cell employing an alkaline electrolyte. It comprises an electrically conductive substrate supporting an electrochemically active material; an interconnecting network of aliphatic alcohol soluble polyamide, the solubility limit of the polyamide in n- propanol being at least about 7.4 percent by weight, linked to the substrate and serving as a binder and an anti- agglomerant retarding cadmium agglomeration during use of the electrode; and a mixture of particulate electrochemically active cadmium material retained in and dispersed through the network and in electrical contact with the substrate during charge and discharge of the electrode.

  4. Effects of cadmium on hypoxia-induced expression of hemoglobin and erythropoietin in larval sheepshead minnow, Cyprinodon variegatus

    International Nuclear Information System (INIS)

    Dangre, A.J.; Manning, S.; Brouwer, M.

    2010-01-01

    Hypoxia and toxic metals are two common stressors found in the estuarine environment. To date little information is available on the combined effects of these stressors on early larval development in fish. We investigated the effect of cadmium and hypoxia exposure alone as well in combination on larval Cyprinodon variegatus. The LC 10 for cadmium was determined to be 0.3 ppm in a 96 h acute exposure. This concentration was used in all studies. Cadmium in larvae increased significantly with exposure time (1, 3, 5 and 7 days post-hatch). The increase was proportional to body weight and not affected by hypoxia. Cadmium responsive genes were identified by suppression subtractive hybridization (SSH) in Cyprinodonvariegatus larvae after exposure to cadmium for 1, 3, 5 and 7 days. We obtained over 700 sequences from the cadmium cDNA library. Blast search of ESTs suggested that cadmium modulates multiple physiological processes. Pertinent to this study, cadmium was found to down-regulate both embryonic α and β globin, which are expressed in erythrocytes generated during the first, or primitive, wave of erythropoiesis in teleosts. Hemoglobin (Hb) and erythropoietin (Epo) (the hormone that promotes red blood cell production) are known hypoxia-inducible genes. To explore the possibility that cadmium might offset the hypoxia-induced expression of Hb and Epo, we investigated the expression of both genes following hypoxia, cadmium and combined exposures for 1, 3, 5 and 7 days post-hatch. Since Epo had not yet been identified in C. variegatus we first successfully cloned a partial coding sequence of the C. variegatus hormone. Subsequent studies revealed that expression levels of Hb and Epo remained unchanged in the normoxic controls during the time course of the study. Hypoxia increased Epo expression relative to normoxic controls, on days 3, 5 and 7, while cadmium in hypoxia inhibited the increase. Only the changes on days 5 and 7 were statistically significant. Hypoxia also

  5. The influence of blast furnace slag, fly ash and silica fume on corrosion of reinforced concrete in marine environment

    NARCIS (Netherlands)

    Polder, R.B.

    1996-01-01

    Chloride penetration from sea water may cause corrosion of reinforcement in concrete structures. Adding reactive inorganic materials such as blast furnace slag, fly ash or silica fume to the cement matrix improves the resistance against chloride penetration as compared to Portland cement concrete. A

  6. Control of exposure to hexavalent chromium concentration in shielded metal arc welding fumes by nano-coating of electrodes.

    Science.gov (United States)

    Sivapirakasam, S P; Mohan, Sreejith; Santhosh Kumar, M C; Thomas Paul, Ashley; Surianarayanan, M

    2018-02-20

    Background Cr(VI) is a suspected human carcinogen formed as a by-product of stainless steel welding. Nano-alumina and nano-titania coating of electrodes reduced the welding fume levels. Objective To investigate the effect of nano-coating of welding electrodes on Cr(VI) formation rate (Cr(VI) FR) from a shielded metal arc welding process. Methods The core welding wires were coated with nano-alumina and nano-titania using the sol-gel dip coating technique. Bead-on plate welds were deposited on SS 316 LN plates kept inside a fume test chamber. Cr(VI) analysis was done using an atomic absorption spectrometer (AAS). Results A reduction of 40% and 76%, respectively, in the Cr(VI) FR was observed from nano-alumina and nano-titania coated electrodes. Increase in the fume level decreased the Cr(VI) FR. Discussion Increase in fume levels blocked the UV radiation responsible for the formation of ozone thereby preventing the formation of Cr(VI).

  7. Association between cooking oil fume exposure and lung cancer among Chinese nonsmoking women: a meta-analysis.

    Science.gov (United States)

    Xue, Yingbo; Jiang, Ying; Jin, Shan; Li, Yong

    2016-01-01

    Lung cancer has been the main cause of cancer death around the world. Cigarette smoking has been identified as a risk factor for lung cancer in males. However, the etiological factors in nonsmoking women remain elusive. A meta-analysis was conducted to evaluate the relationship between cooking oil fume exposure and lung cancer among Chinese nonsmoking women. Thirteen articles containing three population-based case-control and ten hospital-based case-control studies were included in this meta-analysis. These studies with a total of 3,596 lung cancer women and 6,082 healthy controls were analyzed by RevMan 5.3. Fixed effects model or random effects model was used to obtain pooled estimates of risk ratio. The risk ratios with a 95% CI were 1.74 (95% CI =1.57-1.94) and 2.11 (95% CI =1.54-2.89), respectively. Cooking oil fume exposure as well as not using a kitchen ventilator when cooking was significantly associated with lung cancer among nonsmoking women (Z=10.07, Poil fume exposure, especially lacking a fume extractor, may increase the risk of lung cancer among Chinese nonsmoking women.

  8. 42 CFR 84.1153 - Dust, fume, mist, and smoke tests; canister bench tests; gas masks canisters containing filters...

    Science.gov (United States)

    2010-10-01

    ... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1153 Dust... tests; gas masks canisters containing filters; minimum requirements. 84.1153 Section 84.1153 Public...

  9. Cadmium Concentration in Human Autopsy Tissues.

    Science.gov (United States)

    Lech, Teresa; Sadlik, Józefa K

    2017-10-01

    The concentration of cadmium in human tissues obtained on the basis of autopsies of non-poisoned Polish people (n = 150), aged from 1 to 80 years, examined between 1990 and 2010, is presented. The following values were found in wet digested samples by flame atomic absorption spectrometry (FAAS) (mean ± SD, median, and range, μg/g of wet weight): brain 0.020 ± 0.031, 0.084, 0-0.120 (n = 41); stomach 0.148 ± 0.195, 0.084, 0-1.25 (n = 89); small intestine 0.227 ± 0.231, 0.130, 0-0.830 (n = 39); liver 1.54 ± 1.55, 1.01, 0.015-9.65 (n = 99); kidney 16.0 ± 13.2, 14.0, 0.62-61.3 (n = 91); lung 0.304 ± 0.414, 0.130, 0-1.90 (n = 25); and heart 0.137 ± 0.107, 0.140, 0.017-0.250 (n = 4). Additionally, results (n = 13 people, aged from 2 to 83 years, 63 samples) obtained by inductively coupled plasma optical emission spectrometry (ICP OES) between 2010 and 2015 are given. The obtained data on Cd concentration in the human body can be used to estimate the amounts occurring in "healthy" people and those occurring in cases of chronic or acute poisonings with Cd compounds, which are examined for forensic purposes or to assess environmental exposure levels.

  10. Cadmium stress in wheat seedlings: growth, cadmium accumulation and photosynthesis

    DEFF Research Database (Denmark)

    Ci, Dunwei; Jiang, Dong; Wollenweber, Bernd

    2010-01-01

    Cd concentrations in shoots and roots could be explained by the regression model Y = K/(1 + exp(a + bX)). Jing 411 was found to be Cd tolerant considering parameters of chlorophyll content, photosynthesis and chlorophyll fluorescence in which less Cd translocation was from roots into shoots. The high......Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50 μM of CdCl2 in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas exchange, and Cd accumulation in wheat...... parameters were generally depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis and fluorescence and corrected...

  11. Influence of anionic composition during electrodeposition of cadmium from cadmium trilonate electrolyte

    International Nuclear Information System (INIS)

    Kovyazina, L.I.; Timonyuk, V.M.; Ovchinnikova, T.M.

    1982-01-01

    The studies have been conducted to indicate that out of sulfate, chloride, nitrate and hydroxide trilonate electrolytes of cadmium plating consisting (kg/m 3 ): cadmium salt (in conversion to metal) - 31-35, trilon B-120-130, pH 6.5-7.5, cadmium chloride and cadmium sulfate electrolytes are the best ones. They possess high technological parameters (the quality of cathode deposition, the yield in current, disperbility). Comparison of protective properties of coatings of these electrolytes has shown that coatings of chloride electrolytes are less porous and more corrosion resistant

  12. Profiling stainless steel welding processes to reduce fume emissions, hexavalent chromium emissions and operating costs in the workplace.

    Science.gov (United States)

    Keane, Michael; Siert, Arlen; Stone, Samuel; Chen, Bean T

    2016-01-01

    Nine gas metal arc welding (GMAW) processes for stainless steel were assessed for fume generation rates, fume generation rates per g of electrode consumed, and emission rates for hexavalent chromium (Cr(6+)). Elemental manganese, nickel, chromium, iron emissions per unit length of weld, and labor plus consumables costs were similarly measured. Flux-cored arc welding and shielded metal arc (SMAW) processes were also studied. The objective was to identify the best welding processes for reducing workplace exposures, and estimate costs for all processes. Using a conical chamber, fumes were collected, weighed, recovered, and analyzed by inductively coupled atomic emission spectroscopy for metals, and by ion chromatography for Cr(6+). GMAW processes used were Surface Tension Transfer, Regulated Metal Deposition, Cold Metal Transfer, short-circuit, axial spray, and pulsed spray modes. Flux-cored welding used gas shielding; SMAW used E308 rods. Costs were estimated as dollars per m length of a ¼ in (6.3 mm) thick horizontal butt weld; equipment costs were estimated as ratios of new equipment costs to a 250 ampere capacity SMAW welding machine. Results indicate a broad range of fume emission factors for the processes studied. Fume emission rates per g of electrode were lowest for GMAW processes such as pulsed-spray mode (0.2 mg/g), and highest for SMAW (8 mg fume/g electrode). Emission rates of Cr(6+) ranged from 50-7800 µg/min, and Cr(6+) generation rates per g electrode ranged from 1-270 µg/g. Elemental Cr generation rates spanned 13-330 µg/g. Manganese emission rates ranged from 50-300 µg/g. Nickel emission rates ranged from 4-140 µg/g. Labor and consumables costs ranged from $3.15 (GMAW pulsed spray) to $7.40 (SMAW) per meter of finished weld, and were measured or estimated for all 11 processes tested. Equipment costs for some processes may be as much as five times the cost of a typical SMAW welding machine. The results show that all of the GMAW processes in this

  13. Comparative Genotoxicity of Cadmium and Lead in Earthworm Coelomocytes

    Directory of Open Access Journals (Sweden)

    Ptumporn Muangphra

    2011-01-01

    Full Text Available To determine genotoxicity to coelomocytes, Pheretima peguana earthworms were exposed in filter paper studies to cadmium (Cd and lead (Pb for 48 h, at concentrations less than the LC10—Cd: 0.09, 0.19, 0.38, 0.75, and 1.50 μg cm−2; Pb: 1.65, 3.29, 6.58, 13.16, and 26.32 μg cm−2. For Cd at 0.75 μg cm−2, in the micronucleus test (detects chromosomal aberrations, significant increases (<.05 in micronuclei and binucleate cells were observed, and in the comet assay (detects DNA single-strand breaks, tail DNA% was significantly increased. Lead was less toxic with minimal effects on DNA, but the binucleates were significantly increased by Pb at 3.29 μg cm−2. This study shows that Cd is more acutely toxic and sublethally genotoxic than Pb to P. peguana. Cadmium caused chromosomal aberrations and DNA single-strand breaks at 45% of the LC10 concentration. Lead, in contrast, did not induce DNA damage but caused cytokinesis defects.

  14. Particle release and control of worker exposure during laboratory-scale synthesis, handling and simulated spills of manufactured nanomaterials in fume hoods

    Science.gov (United States)

    Fonseca, Ana S.; Kuijpers, Eelco; Kling, Kirsten I.; Levin, Marcus; Koivisto, Antti J.; Nielsen, Signe H.; Fransman, W.; Fedutik, Yijri; Jensen, Keld A.; Koponen, Ismo K.

    2018-02-01

    Fume hoods are one of the most common types of equipment applied to reduce the potential of particle exposure in laboratory environments. A number of previous studies have shown particle release during work with nanomaterials under fume hoods. Here, we assessed laboratory workers' inhalation exposure during synthesis and handling of CuO, TiO2 and ZnO in a fume hood. In addition, we tested the capacity of a fume hood to prevent particle release to laboratory air during simulated spillage of different powders (silica fume, zirconia TZ-3Y and TiO2). Airborne particle concentrations were measured in near field, far field, and in the breathing zone of the worker. Handling CuO nanoparticles increased the concentration of small particles (handling and packaging of ZnO and TiO2 nanoparticles did not result in detectable particle release to the laboratory air. Simulated powder spills showed a systematic increase in the particle concentrations inside the fume hood with increasing amount of material and drop height. Despite powder spills were sometimes observed to eject into the laboratory room, the spill events were rarely associated with notable release of particles from the fume hood. Overall, this study shows that a fume hood generally offers sufficient exposure control during synthesis and handling of nanomaterials. An appropriate fume hood with adequate sash height and face velocity prevents 98.3% of particles release into the surrounding environment. Care should still be made to consider spills and high cleanliness to prevent exposure via resuspension and inadvertent exposure by secondary routes.

  15. Particle release and control of worker exposure during laboratory-scale synthesis, handling and simulated spills of manufactured nanomaterials in fume hoods.

    Science.gov (United States)

    Fonseca, Ana S; Kuijpers, Eelco; Kling, Kirsten I; Levin, Marcus; Koivisto, Antti J; Nielsen, Signe H; Fransman, W; Fedutik, Yijri; Jensen, Keld A; Koponen, Ismo K

    2018-01-01

    Fume hoods are one of the most common types of equipment applied to reduce the potential of particle exposure in laboratory environments. A number of previous studies have shown particle release during work with nanomaterials under fume hoods. Here, we assessed laboratory workers' inhalation exposure during synthesis and handling of CuO, TiO 2 and ZnO in a fume hood. In addition, we tested the capacity of a fume hood to prevent particle release to laboratory air during simulated spillage of different powders (silica fume, zirconia TZ-3Y and TiO 2 ). Airborne particle concentrations were measured in near field, far field, and in the breathing zone of the worker. Handling CuO nanoparticles increased the concentration of small particles (handling and packaging of ZnO and TiO 2 nanoparticles did not result in detectable particle release to the laboratory air. Simulated powder spills showed a systematic increase in the particle concentrations inside the fume hood with increasing amount of material and drop height. Despite powder spills were sometimes observed to eject into the laboratory room, the spill events were rarely associated with notable release of particles from the fume hood. Overall, this study shows that a fume hood generally offers sufficient exposure control during synthesis and handling of nanomaterials. An appropriate fume hood with adequate sash height and face velocity prevents 98.3% of particles release into the surrounding environment. Care should still be made to consider spills and high cleanliness to prevent exposure via resuspension and inadvertent exposure by secondary routes.

  16. Non-occupational exposure to paint fumes during pregnancy and risk of congenital anomalies: a cohort study.

    Science.gov (United States)

    Hjortebjerg, Dorrit; Andersen, Anne-Marie Nybo; Garne, Ester; Raaschou-Nielsen, Ole; Sørensen, Mette

    2012-08-14

    Occupational exposure to organic solvents during the 1st trimester of pregnancy has been associated with congenital anomalies. Organic solvents are also used in the home environments in paint products, but no study has investigated the effect of such exposure in a general population. We studied associations between residential exposure to paint fumes during the 1st trimester of pregnancy and predefined subgroups of congenital anomalies, using data from the Danish National Birth Cohort (DNBC). During 2001 and 2003, a total of 20,103 pregnant women, enrolled in the DNBC, were interviewed in the 30th week of gestation about the use of paint in their residence during pregnancy. By the end of first trimester, information about smoking habits, alcohol consumption and occupation were collected. Information on congenital anomalies was obtained from national registers. Associations were examined by estimating odds ratios (OR) using logistic regression. In total 1404 women (7%) had been exposed to paint fumes during the 1st trimester of pregnancy and 1086 children were diagnosed with congenital anomalies; 73 children with congenital anomalies had been exposed to paint fumes in utero. Exposure to paint fumes seemed positively associated with congenital anomalies of the nervous system (OR 2.19, 95% confidence interval (CI) 0.76 to 6.32), ear, face and neck (OR 2.15, 95% CI 0.84 to 5.55) and the renal system (OR 2.16, 95% CI 1.02 to 4.58) after adjustment for maternal age, smoking, alcohol consumption and occupational solvent exposure. Congenital anomalies in the remaining subgroups were not associated with the exposure. Our results suggest that in the general population, exposure to paint fumes during the 1st trimester of pregnancy may increase the risk of some types of congenital anomalies, but the findings need to be confirmed.

  17. Non-occupational exposure to paint fumes during pregnancy and risk of congenital anomalies: a cohort study

    Directory of Open Access Journals (Sweden)

    Hjortebjerg Dorrit

    2012-08-01

    Full Text Available Abstract Background Occupational exposure to organic solvents during the 1st trimester of pregnancy has been associated with congenital anomalies. Organic solvents are also used in the home environments in paint products, but no study has investigated the effect of such exposure in a general population. Methods We studied associations between residential exposure to paint fumes during the 1st trimester of pregnancy and predefined subgroups of congenital anomalies, using data from the Danish National Birth Cohort (DNBC. During 2001 and 2003, a total of 20 103 pregnant women, enrolled in the DNBC, were interviewed in the 30th week of gestation about the use of paint in their residence during pregnancy. By the end of first trimester, information about smoking habits, alcohol consumption and occupation were collected. Information on congenital anomalies was obtained from national registers. Associations were examined by estimating odds ratios (OR using logistic regression. Results In total 1404 women (7% had been exposed to paint fumes during the 1st trimester of pregnancy and 1086 children were diagnosed with congenital anomalies; 73 children with congenital anomalies had been exposed to paint fumes in utero. Exposure to paint fumes seemed positively associated with congenital anomalies of the nervous system (OR 2.19, 95% confidence interval (CI 0.76 to 6.32, ear, face and neck (OR 2.15, 95% CI 0.84 to 5.55 and the renal system (OR 2.16, 95% CI 1.02 to 4.58 after adjustment for maternal age, smoking, alcohol consumption and occupational solvent exposure. Congenital anomalies in the remaining subgroups were not associated with the exposure. Conclusions Our results suggest that in the general population, exposure to paint fumes during the 1st trimester of pregnancy may increase the risk of some types of congenital anomalies, but the findings need to be confirmed.

  18. Inhalation of gas metal arc-stainless steel welding fume promotes lung tumorigenesis in A/J mice.

    Science.gov (United States)

    Falcone, Lauryn M; Erdely, Aaron; Meighan, Terence G; Battelli, Lori A; Salmen, Rebecca; McKinney, Walter; Stone, Samuel; Cumpston, Amy; Cumpston, Jared; Andrews, Ronnee N; Kashon, Michael; Antonini, James M; Zeidler-Erdely, Patti C

    2017-08-01

    Epidemiologic studies suggest an increased risk of lung cancer with exposure to welding fumes, but controlled animal studies are needed to support this association. Oropharyngeal aspiration of collected "aged" gas metal arc-stainless steel (GMA-SS) welding fume has been shown by our laboratory to promote lung tumor formation in vivo using a two-stage initiation-promotion model. Our objective in this study was to determine whether inhalation of freshly generated GMA-SS welding fume also acts as a lung tumor promoter in lung tumor-susceptible mice. Male A/J mice received intraperitoneal (IP) injections of corn oil or the chemical initiator 3-methylcholanthrene (MCA; 10 µg/g) and 1 week later were exposed by whole-body inhalation to air or GMA-SS welding aerosols for 4 h/d × 4 d/w × 9 w at a target concentration of 40 mg/m 3 . Lung nodules were enumerated at 30 weeks post-initiation. GMA-SS fume significantly promoted lung tumor multiplicity in A/J mice initiated with MCA (16.11 ± 1.18) compared to MCA/air-exposed mice (7.93 ± 0.82). Histopathological analysis found that the increased number of lung nodules in the MCA/GMA-SS group were hyperplasias and adenomas, which was consistent with developing lung tumorigenesis. Metal deposition analysis in the lung revealed a lower deposited dose, approximately fivefold compared to our previous aspiration study, still elicited a significant lung tumorigenic response. In conclusion, this study demonstrates that inhaling GMA-SS welding fume promotes lung tumorigenesis in vivo which is consistent with the epidemiologic studies that show welders may be at an increased risk for lung cancer.

  19. Association between cooking oil fume exposure and lung cancer among Chinese nonsmoking women: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Xue Y

    2016-05-01

    Full Text Available Yingbo Xue, Ying Jiang, Shan Jin, Yong Li Department of Oncology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, People’s Republic of China Abstract: Lung cancer has been the main cause of cancer death around the world. Cigarette smoking has been identified as a risk factor for lung cancer in males. However, the etiological factors in nonsmoking women remain elusive. A meta-analysis was conducted to evaluate the relationship between cooking oil fume exposure and lung cancer among Chinese nonsmoking women. Thirteen articles containing three population-based case–control and ten hospital-based case–control studies were included in this meta-analysis. These studies with a total of 3,596 lung cancer women and 6,082 healthy controls were analyzed by RevMan 5.3. Fixed effects model or random effects model was used to obtain pooled estimates of risk ratio. The risk ratios with a 95% CI were 1.74 (95% CI =1.57–1.94 and 2.11 (95% CI =1.54–2.89, respectively. Cooking oil fume exposure as well as not using a kitchen ventilator when cooking was significantly associated with lung cancer among nonsmoking women (Z=10.07, P<0.00001; Z=4.65, P<0.00001. Cooking oil fume exposure, especially lacking a fume extractor, may increase the risk of lung cancer among Chinese nonsmoking women. Keywords: cooking oil fume exposure, lung cancer, meta-analysis, nonsmoking women 

  20. Large silver-cadmium technology program

    Science.gov (United States)

    Charlip, S.; Lerner, S.

    1971-01-01

    The effects of varying cell design on operation factors on the electrochemical performance of sealed, silver-cadmium cells were determined. A factorial experiment was conducted for all test cells constructed with organic separators. Three operating factors were evaluated: temperature, depth of discharge, and charge rate. The six construction factors considered were separator, absorber, electrolyte quantity, cadmium electrode type, cadmium-to-silver ratio, and auxiliary electrode. Test cells of 4 ampere-hour capacity were fabricated and cycled. The best performing cells, on a 94 minute orbit, at 40% depth of discharge, were those containing silver-treated fibrous sausage casings as the separator, and Teflon-ated, pressed cadmium electrodes. Cycling data of cells with inorganic separators (Astroset) are given. Best performance was shown by cells with nonwoven nylon absorbers. Rigid inorganic separators provided the best barrier to silver migration.

  1. RISK ASSESSMENT AND MANAGEMENT OF ENVIRONMENTAL CADMIUM

    Science.gov (United States)

    Cadmium consumed in foods grown on soils contaminated by industrial Cd+Zn discharge has caused renal tubular dysfunction in exposed humans in discrete situations. However, lack of understanding about environmental Cd has caused wide concern that generalpopulations may...

  2. Cadmium substituted high permeability lithium ferrite

    Indian Academy of Sciences (India)

    , 0.5 and 0.6 were prepared by a double sintering ceramic technique and characterized by X-ray diffraction and scanning electron microscopy (SEM). The lattice parameter is found to increase monotonically with the cadmium content.

  3. Solvent extraction studies on cadmium Pt. 1

    International Nuclear Information System (INIS)

    Alian, A.; El-Kot, A.; Badran, A.; El-Bassiouny, M.S.

    1975-01-01

    An extraction study was performed on tracer concentrations of cadmium halides in absence and presence of sulphuric acid. Inert solvents, nitrobenzene, a long chain amine (Amberlite LA-2) and organophosphorus solvents (TBP and HDEHP) have been investigated. The comparative stability of cadmium chloride and bromide TBP solvates were determined. The presence of sulphuric acid was found to enhance considerably the extraction of cadmium halides by nitrobenzene, Amberlite LA-2 and TBP. The mechanism of extraction has been discussed in light of the obtained results. The systems studied involved halide ions (Cl, Br and I), sulphuric and phosphoric acids. In these systems extraction was negligible for all nonpolar solvents, considerable for nitrobenzene and very high for Amberlite LA-2 and TBP. Work has been carried out for both micro and macro scales in case of sulphuric acid system, and only for the microscale in case of phosphoric acid system, because of the limited solubility of cadmium phosphate in aqueous solutions. (T.G.)

  4. Cadmium induced nephrotoxicity in rats.

    Science.gov (United States)

    Lall, S B; Das, N; Rama, R; Peshin, S S; Khattar, S; Gulati, K; Seth, S D

    1997-02-01

    Onset of hypertension and nephropathy after 1,2, and 4 weeks of exposure to cadmium chloride (1 mg/kg, ip) was studied in rats by measuring changes in blood pressure and renal function (urinary output, electrolytes, serum creatinine, inulin clearance and Na+K+ ATPase). Significant decrease in body weight and rise in blood pressure were observed as early as one week of exposure while microalbuminuria was detected in 50% of the animals after 2 weeks. Na+K+ ATPase, a renal tubular enzyme, was depressed after 1 week with maximum lowering occurring after 4 weeks. There were no detectable changes in fluid intake, urine output, electrolytes, inulin clearance and serum creatinine even after 4 weeks. It is concluded that hypertension and tubular lesion set in earlier than glomerulopathy as indicated by microalbuminuria and the latter could be the consequence of rise in blood pressure.

  5. Exposure to Cadmium Impairs Sperm Functions by Reducing CatSper in Mice

    Directory of Open Access Journals (Sweden)

    Hua-Feng Wang

    2017-05-01

    Full Text Available Background: Cadmium (Cd, a common environmental heavy metal and endocrine disruptor, is known to exert toxic effects on the testes. However, the mechanisms accounting for its toxicity in mature spermatozoa remain unclear. Methods: Adult male C57BL/6 mice were orally administered with CdCl2 for 5 weeks at 3 mg·kg-1·day-1. Additionally, mouse spermatozoa were incubated in vitro with different doses of CdCl2 (0, 10, 50, 250 µM. Several sperm functions including the sperm motility, viability and acrosome reaction (AR ratio were then examined. Furthermore, the current and expression levels of both the sperm-specific Ca2+ channel (CatSper and the sperm-specific K+ channel (KSper were evaluated by patch-clamping and western blotting, respectively. Results: Our data showed that the motility, viability and AR of sperm exposed to cadmium significantly decreased in vivo and in vitro. Interestingly, these changes were correlated with changes in CatSper but not KSper. Conclusion: The findings indicate sperm dysfunction during both chronic and acute cadmium exposure as well as a specific role for CatSper in the reproductive toxicity of cadmium.

  6. Suppression of interleukin-1[beta] and tumour necrosis factor-[alpha] biosynthesis by cadmium in in vitro activated human peripheral blood mononuclear cells

    Energy Technology Data Exchange (ETDEWEB)

    Theocharis, S.E. (Dept. of Experimental Pharmacology, School of Medicine, Univ. of Athens (Greece) First Dept. of Internal Medicine, School of Medicine, Univ. of Athens, Laikon Hospital (Greece)); Panayiotidis, P.G. (First Dept. of Internal Medicine, School of Medicine, Univ. of Athens, Laikon Hospital (Greece)); Souliotis, V.L. (National Hellenic Research Foundation, Inst. of Biological Research and Biotechnology, Athens (Greece))

    1994-12-01

    Cadmium is a highly toxic element responsible for acute and chronic toxicity in man. There is evidence that cadmium induces pathophysiological effects by modulating components of the immune system. Cytokines are being increasingly recognized as essential mediators of normal and pathologic immune responses. Cadmium at concentrations varying from 1.0x10[sup -4] to 3.3x10[sup -6] M inhibited the phytohemagglutinin induced production of interleukin-1[beta] and tumour necrosis factor-[alpha], in in vitro activated human peripheral blood mononuclear cells. The messenger RNA levels of interleukin-1[beta] and tumour necrosis factor-[alpha] were examined during a 24-h culture period, at different time points. The decreased messenger RNA levels at the time points of the maximum expression of interleukin-1[beta] and tumour necrosis factor-[alpha] indicate that cadmium suppresses their production at the transcriptional level. (orig.)

  7. Cadmium poisoning. Knowledge of the risk

    International Nuclear Information System (INIS)

    Peltier, A.; Demange, M.; Carton, M.B.

    1979-01-01

    This data sheet provides an up-to-date summary of information on cadmium poisoning. The following points are examined: - the problem of increasing pollution of soil, water and the food chain; - physical and chemical properties, manufacture, industrial applications; - the toxic action of cadmium and its derivatives; - methods and apparatus for taking and analysis samples from the atmosphere and from body fluids; - existing French regulations; - technical control and medical surveillance [fr

  8. Possible actions for the minimization of the environmental impact of the iron ore sintering fumes

    International Nuclear Information System (INIS)

    Garcia-Carcedo, F.; Ayala, N.; Isidro, A.; Moro, A.; Cornejo, N.; Ferreira, S.; Hernandez, A.; Cobo, A.; Alaiz, E.; Garcia, J. R.

    2004-01-01

    In sintering plants, gaseous emissions are generated which must comply with increasingly demanding environmental regulations. In the sintering process, about 40 kg of coke and 1,700 Nm''3 of air are used per ton of useful sinter. Sintering fumes have a gaseous phase formed mainly of N 2 , O 2 , CO 2 , H 2 O and CO and the minor components SO . SO 3 , NO and NO 2 . Other minor components include unburned organic products and CLH, and minimal proportions of other high impact compounds such as dioxins and furans are also present. Chlorides and heavy metals are present in the solid fraction. This paper reviews the situation of each emission in relation with the applicable regulations, and the possible means of reducing these emissions. (Author) 12 refs

  9. Carbonation of ternary cementitious concrete systems containing fly ash and silica fume

    Directory of Open Access Journals (Sweden)

    Eehab Ahmed Badreldin Khalil

    2015-04-01

    Full Text Available Carbonation is quite a complex physical negative effect phenomenon on concrete especially in the ones containing ternary blends of Portland Cement, fly ash, and silica fume. Nine selected concrete mixtures were prepared with various water to cementitious materials’ ratios and various cementitious contents. The concrete mixtures were adapted in such a way to have the same workability and air content. The fresh concrete properties were kept near identical in slump, air content, and unit weight. The variation was in the hardened concrete mechanical properties of compression and tension strength. The carbonation phenomenon was studied for these mixes showing at which mixes of ternary cementitious content heavy carbonation attacks maybe produced. The main components of such mixes that do affect the carbonation process with time were presented.

  10. Effect of Undensified Silica Fume on the Dispersion of Carbon Nanotubes within a Cementitious Composite

    Science.gov (United States)

    Alrekabi, S.; Cundy, A.; Whitby, Raymond L. D.; Lampropoulos, A.; Savina, I.

    2017-04-01

    The synergistic effect of multi-walled carbon nanotubes (MWCNTs) and Undensified Silica Fume (USF) on the microstructure of cementitious composites has been studied. In the current work, USF was used to enhance the dispersion of nanotubes throughout the composite and prevent the re-agglomeration of nanotubes by providing a physical barrier of particles of small size. Ultrasonication was employed to disperse MWCNTs in water in the presence of polycarboxylate-based superplasticizer (PCE) as a dispersion agent. The results indicate that incorporation of USF considerably improves the dispersion of nanotubes in the composites, with subsequent enhancement of composite packing density. This enhancement can be attributed to the synergistic effect of MWCNTs and USF in reducing the volume of pores through the cementitious composites.

  11. Fumed silica nanoparticle mediated biomimicry for optimal cell-material interactions for artificial organ development.

    Science.gov (United States)

    de Mel, Achala; Ramesh, Bala; Scurr, David J; Alexander, Morgan R; Hamilton, George; Birchall, Martin; Seifalian, Alexander M

    2014-03-01

    Replacement of irreversibly damaged organs due to chronic disease, with suitable tissue engineered implants is now a familiar area of interest to clinicians and multidisciplinary scientists. Ideal tissue engineering approaches require scaffolds to be tailor made to mimic physiological environments of interest with specific surface topographical and biological properties for optimal cell-material interactions. This study demonstrates a single-step procedure for inducing biomimicry in a novel nanocomposite base material scaffold, to re-create the extracellular matrix, which is required for stem cell integration and differentiation to mature cells. Fumed silica nanoparticle mediated procedure of scaffold functionalization, can be potentially adapted with multiple bioactive molecules to induce cellular biomimicry, in the development human organs. The proposed nanocomposite materials already in patients for number of implants, including world first synthetic trachea, tear ducts and vascular bypass graft. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Formulation of a grease from spent bleaching earth, waste cooking oil and fumed silica as additives

    International Nuclear Information System (INIS)

    Mohd Khairul Nizam Mohd Zuhan; Hayder Abdul Bari

    2010-01-01

    The study is to formulate new multi-purpose grease from industrial wastes. In this study we intent to use waste cooking oil and spent bleaching earth as a main ingredients for the grease formulation. Additives such as fumed silica, molybdenum disulphide and other type of additives are introduced to improve the properties of the grease. The best percentage of waste cooking oil, spent bleaching earth and additives added is determined (w/w) during this study to produces the best consistency through penetration test based on NGLI standard. Other properties being determined include drop point, oxidation stability, and oil separation test through ASTM method. From result obtained, some necessary modification and additives addition into spent bleaching earth and waste cooking oil can produce new multi-purpose based grease that can be commercialized. (author)

  13. Cadmium affects retinogenesis during zebrafish embryonic development

    International Nuclear Information System (INIS)

    Hen Chow, Elly Suk; Yu Hui, Michelle Nga; Cheng, Chi Wa; Cheng, Shuk Han

    2009-01-01

    Ocular malformations are commonly observed in embryos of aquatic species after exposure to toxicants. Using zebrafish embryos as the model organism, we showed that cadmium exposure from sphere stage (4 hpf) to end of segmentation stage (24 hpf) induced microphthalmia in cadmium-treated embryos. Embryos with eye defects were then assessed for visual abilities. Cadmium-exposed embryos were behaviorally blind, showing hyperpigmentation and loss of camouflage response to light. We investigated the cellular basis of the formation of the small eyes phenotype and the induction of blindness by studying retina development and retinotectal projections. Retinal progenitors were found in cadmium-treated embryos albeit in smaller numbers. The number of retinal ganglion cells (RGC), the first class of retinal cells to differentiate during retinogenesis, was reduced, while photoreceptor cells, the last batch of retinal neurons to differentiate, were absent. Cadmium also affected the propagation of neurons in neurogenic waves. The neurons remained in the ventronasal area and failed to spread across the retina. Drastically reduced RGC axons and disrupted optic stalk showed that the optic nerves did not extend from the retina beyond the chiasm into the tectum. Our data suggested that impairment in neuronal differentiation of the retina, disruption in RGC axon formation and absence of cone photoreceptors were the causes of microphthalmia and visual impairment in cadmium-treated embryos

  14. Cadmium leaching from thermal treated and gamma irradiated Mexican aluminosilicates

    Energy Technology Data Exchange (ETDEWEB)

    Davila-Rangel, J.I. [Departamento de Quimica, Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, Mexico 11801, D.F. (Mexico); Unidad Academica Centro Regional de Estudios Nucleares, Universidad Autonoma de Zacatecas Cipres 10, Frac. La Penuela, Zacatecas, Zacatecas 98068 (Mexico); Facultad de Ciencias, Universidad Autonoma del Estado de Mexico, Instituto Literario No. 100 Col. Centro C.P. 50000, Toluca, Edo. de Mexico (Mexico); Solache-Rios, M. [Departamento de Quimica, Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, Mexico 11801, D.F. (Mexico)], E-mail: msr@nuclear.inin.mx

    2008-10-15

    Thermal and radiation effects on the leaching of cadmium from two cadmium exchanged zeolitic tuffs and one clay were determined. The cadmium exchanged aluminosilicates were heated at different temperatures (500, 700, 900 and 1100 {sup o}C), and the materials were then treated with NaCl (1 M and 5 M) and HNO{sub 3} (0.001 M and 1 M) solutions to determine the leaching behaviour of cadmium from the materials. The stability of cadmium in the materials increased as the heating temperature was increased. Cadmium leaching from gamma irradiated and heated materials at 1100 {sup o}C was higher than leaching from non-irradiated samples.

  15. Exposure to welding fumes and lower airway infection with Streptococcus pneumoniae.

    Science.gov (United States)

    Suri, Reetika; Periselneris, Jimstan; Lanone, Sophie; Zeidler-Erdely, Patti C; Melton, Geoffrey; Palmer, Keith T; Andujar, Pascal; Antonini, James M; Cohignac, Vanessa; Erdely, Aaron; Jose, Ricardo J; Mudway, Ian; Brown, Jeremy; Grigg, Jonathan

    2016-02-01

    Welders are at increased risk of pneumococcal pneumonia. The mechanism for this association is not known. The capacity of pneumococci to adhere to and infect lower airway cells is mediated by host-expressed platelet-activating factor receptor (PAFR). We sought to assess the effect of mild steel welding fumes (MS-WF) on PAFR-dependent pneumococcal adhesion and infection to human airway cells in vitro and on pneumococcal airway infection in a mouse model. The oxidative potential of MS-WF was assessed by their capacity to reduce antioxidants in vitro. Pneumococcal adhesion and infection of A549, BEAS-2B, and primary human bronchial airway cells were assessed by means of quantitative bacterial culture and expressed as colony-forming units (CFU). After intranasal instillation of MS-WF, mice were infected with Streptococcus pneumoniae, and bronchoalveolar lavage fluid (BALF) and lung CFU values were determined. PAFR protein levels were assessed by using immunofluorescence and immunohistochemistry, and PAFR mRNA expression was assessed by using quantitative PCR. PAFR was blocked by CV-3988, and oxidative stress was attenuated by N-acetylcysteine. MS-WF exhibited high oxidative potential. In A549 and BEAS-2B cells MS-WF increased pneumococcal adhesion and infection and PAFR protein expression. Both CV-3988 and N-acetylcysteine reduced MS-WF-stimulated pneumococcal adhesion and infection of airway cells. MS-WF increased mouse lung PAFR mRNA expression and increased BALF and lung pneumococcal CFU values. In MS-WF-exposed mice CV-3988 reduced BALF CFU values. Hypersusceptibility of welders to pneumococcal pneumonia is in part mediated by the capacity of welding fumes to increase PAFR-dependent pneumococcal adhesion and infection of lower airway cells. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. All rights reserved.

  16. Enantioselective transesterification by Candida antarctica Lipase B immobilized on fumed silica.

    Science.gov (United States)

    Kramer, Martin; Cruz, Juan C; Pfromm, Peter H; Rezac, Mary E; Czermak, Peter

    2010-10-01

    Enzymatic catalysis to produce molecules such as perfumes, flavors, and fragrances has the advantage of allowing the products to be labeled "natural" for marketing in the U.S., in addition to the exquisite selectivity and stereoselectivity of enzymes that can be an advantage over chemical catalysis. Enzymatic catalysis in organic solvents is attractive if solubility issues of reactants or products, or thermodynamic issues (water as a product in esterification) complicate or prevent aqueous enzymatic catalysis. Immobilization of the enzyme on a solid support can address the generally poor solubility of enzymes in most solvents. We have recently reported on a novel immobilization method for Candida antarctica Lipase B on fumed silica to improve the enzymatic activity in hexane. This research is extended here to study the enantioselective transesterification of (RS)-1-phenylethanol with vinyl acetate. The maximum catalytic activity for this preparation exceeded the activity (on an equal enzyme amount basis) of the commercial Novozyme 435(®) significantly. The steady-state conversion for (R)-1-phenylethanol was about 75% as confirmed via forward and reverse reaction. The catalytic activity steeply increases with increasing nominal surface coverage of the support until a maximum is reached at a nominal surface coverage of 230%. We hypothesize that the physical state of the enzyme molecules at a low surface coverage is dominated in this case by detrimental strong enzyme-substrate interactions. Enzyme-enzyme interactions may stabilize the active form of the enzyme as surface coverage increases while diffusion limitations reduce the apparent catalytic performance again at multi-layer coverage. The temperature-, solvent-, and long-term stability for CALB/fumed silica preparations showed that these preparations can tolerate temperatures up to 70°C, continuous exposure to solvents, and long-term storage. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. A Cross-Sectional Study of the Cardiovascular Effects of Welding Fumes.

    Directory of Open Access Journals (Sweden)

    Huiqi Li

    Full Text Available Occupational exposure to particulate air pollution has been associated with an increased risk of cardiovascular disease. However, the risk to welders working today remains unclear. We aimed to elucidate the cardiovascular effects of exposure to welding fumes.In a cross-sectional study, structured interviews and biological sampling were conducted for 101 welders and 127 controls (all non-smoking males from southern Sweden. Personal breathing zone sampling of respirable dust was performed. Blood pressure (BP and endothelial function (using peripheral arterial tonometry were measured. Plasma and serum samples were collected from peripheral blood for measurement of C-reactive protein, low-density lipoprotein, homocysteine, serum amyloid A, and cytokines.Welders were exposed to 10-fold higher levels of particles than controls. Welders had significantly higher BP compared to controls, an average of 5 mm Hg higher systolic and diastolic BP (P ≤ 0.001. IL-8 was 3.4 ng/L higher in welders (P=0.010. Years working as a welder were significantly associated with increased BP (β=0.35, 95%CI 0.13 - 0.58, P=0.0024 for systolic BP; β=0.32, 95%CI 0.16 - 0.48, P<0.001 for diastolic BP, adjusted for BMI but exposure to respirable dust was not associated with BP. No clear associations occurred between welding and endothelial function, or other effect markers.A modest increase in BP was found among welders compared to controls suggesting that low-to-moderate exposure to welding fumes remains a risk factor for cardiovascular disease.

  18. The effect of silica fume and metakaolin on glass-fibre reinforced concrete (GRC ageing

    Directory of Open Access Journals (Sweden)

    Enfedaque Díaz, A.

    2010-12-01

    Full Text Available The deterioration of the mechanical properties of glassfibre reinforced concrete (GRC over time rules out the use of this material in load-bearing structures. While one possible solution to this problem is the addition of pozzolans or metakaolin to the cement mortar, the amounts needed to ensure GRC integrity raise its price to non-competitive levels. Experimental research has been conducted to analyze whether the addition of small amounts of silica fume or metakaolin can prevent or mitigate the ageing issue. Unfortunately, the findings indicate that the addition of small proportions of metakaolin or silica fume to GRC are ineffective in improving its long-term performance.

    Para el uso del mortero de cemento reforzado con fibras de vidrio (GRC en estructuras portantes se han de solucionar los problemas de reducción de las propiedades mecánicas que aparecen con el paso del tiempo. Estos problemas pueden ser solucionados mediante la adición de puzolanas o de metacaolín, a la pasta de mortero de cemento. Sin embargo, la cantidad de metacaolín que ha de ser añadida es elevada y el precio del GRC fabricado está fuera del mercado. Se ha realizado una campaña experimental que analiza si la adición de humo de sílice o de metacaolín en proporciones reducidas consigue evitar o paliar el problema del envejecimiento, que supone un freno al uso del GRC en elementos estructurales. Desgraciadamente, los resultados experimentales muestran que proporciones bajas de metacaolín o de humo de sílice no son efectivas para reducir el problema de pérdida de propiedades mecánicas.

  19. Aerodynamics and performance verifications of test methods for laboratory fume cupboards.

    Science.gov (United States)

    Tseng, Li-Ching; Huang, Rong Fung; Chen, Chih-Chieh; Chang, Cheng-Ping

    2007-03-01

    The laser-light-sheet-assisted smoke flow visualization technique is performed on a full-size, transparent, commercial grade chemical fume cupboard to diagnose the flow characteristics and to verify the validity of several current containment test methods. The visualized flow patterns identify the recirculation areas that would inevitably exist in the conventional fume cupboards because of the fundamental configurations and structures. The large-scale vortex structures exist around the side walls, the doorsill of the cupboard and in the vicinity of the near-wake region of the manikin. The identified recirculation areas are taken as the 'dangerous' regions where the risk of turbulent dispersion of contaminants may be high. Several existing tracer gas containment test methods (BS 7258:1994, prEN 14175-3:2003 and ANSI/ASHRAE 110:1995) are conducted to verify the effectiveness of these methods in detecting the contaminant leakage. By comparing the results of the flow visualization and the tracer gas tests, it is found that the local recirculation regions are more prone to contaminant leakage because of the complex interaction between the shear layers and the smoke movement through the mechanism of turbulent dispersion. From the point of view of aerodynamics, the present study verifies that the methodology of the prEN 14175-3:2003 protocol can produce more reliable and consistent results because it is based on the region-by-region measurement and encompasses the most area of the entire recirculation zone of the cupboard. A modified test method combined with the region-by-region approach at the presence of the manikin shows substantially different results of the containment. A better performance test method which can describe an operator's exposure and the correlation between flow characteristics and the contaminant leakage properties is therefore suggested.

  20. [Association of cooking oil fumes exposure and oxidative DNA damage among occupational exposed populations].

    Science.gov (United States)

    Ke, Yue-bin; Xu, Xin-yun; Yuan, Jian-hui; Fang, Shi-song; Liu, Yi-min; Wu, Tang-chun

    2010-08-01

    Previous investigations indicate that cooks are exposed to polycyclic aromatic hydrocarbons (PAH) from cooking oil fumes (COF). However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene (1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36), all are male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8-OHdG and 1-OHP by high performance liquid chromatography. Excretion in urine of 8-OHdG were similar for controls (mean 1.2 µmol/mol creatinine, n = 36), and for those who had been in the kitchen room with exhaust hood operation (mean 1.5 µmol/mol creatinine, n = 45). COF exposed cooks without exhaust hood operation had increased excretion of 8-OHdG (mean 2.3 µmol/mol creatinine, n = 18). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. Results indicate that exposure to PAH or possibly other compounds in COF may cause oxidative DNA damage.

  1. Cadmium-induced IL-6 and IL-8 expression and release from astrocytes are mediated by MAPK and NF-κB pathways.

    Science.gov (United States)

    Phuagkhaopong, Suttinee; Ospondpant, Dusadee; Kasemsuk, Thitima; Sibmooh, Nathawut; Soodvilai, Sunhapas; Power, Christopher; Vivithanaporn, Pornpun

    2017-05-01

    Chronic exposure to cadmium has been linked to brain cancers, learning disabilities and memory deficits. Previous studies of cadmium toxicity in the central nervous system report cadmium induces oxidative stress in neurons and astrocytes. In the peripheral system, cadmium promotes interleukin-6 (IL-6) and IL-8 production and release. Elevation of IL-6 expression is linked to the pathogenesis of neurodegenerative diseases and astrogliosis. IL-8 plays a role in angiogenesis of gliomas and neurodegenerative diseases. Herein, the effects of non-toxic concentrations of cadmium on the production of IL-6 and IL-8 and the underlying mechanisms were investigated. U-87 MG human astrocytoma cells and primary human astrocytes were exposed to cadmium chloride. At 24h post-exposure to 1 and 10μM, levels of intracellular cadmium in U-87 MG cells were 11.89±3.59 and 53.08±7.59μg/g wet weight, respectively. These concentrations had minimal effects on cell morphology and viability. IL-6 and IL-8 mRNA levels and secretion increased in dose- and time-dependent manners post cadmium exposure. Acute exposure to cadmium increased phosphorylation of ERK1/2, p38 MAPK, and p65 NF-κB. Pretreatment with U0126-an inhibitor of MEK1 and MEK2 kinases-SB203580-a p38 MAPK inhibitor-and SC-514-an IKKβ inhibitor-suppressed cadmium-induced IL-8 expression and release. Upregulation of cadmium-induced IL-6 was inhibited by U0126 and SC-514, but not SB203580. On the other hand, SP600125-a JNK inhibitor-and celecoxib-a selective COX-2 inhibitor-had no effect on production of both cytokines. In conclusion, non-toxic concentrations of cadmium can stimulate IL-6 and IL-8 release through MAPK phosphorylation and NF-κB activation. Suppressing IL-6 and IL-8 production could be novel approaches to prevent cadmium-induced angiogenesis in gliomas and inflammation in the brain. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Determination of cadmium oxide in and on the surface of high purity cadmium metal

    International Nuclear Information System (INIS)

    Kiba, Toshiyasu; Matsumoto, Ken; Shimizu, Genji

    1975-01-01

    In a 100 ml separating funnel were added 50 ml of 1 M ammonium chloride-aqueous ammonia buffer solution(pH 10) and 2.5 ml mercury; after passing nitrogen gas sufficiently to remove oxygen from the vessel and also from the aqueous solution, several pieces of cadmium metal of high purity were put into the vessel. The content was shaken vigorously; the metal went into mercury forming cadmium-amalgam, while the cadmium oxide dissolved itself in the aqueous solution to form cadmium tetrammine complex cations. After Removal of mercury from the funnel, the solution was submitted to the determination of cadmium dissolved in it by means of the atomic absorption spectrophotometry of the EDTA titration. By the above procedure a minute amount of cadmium oxide could be determined precisely with high reproducibility. The critical experiments were also done to clarify the behaviors of cadmium metal and cadmium oxide in this separation process for the purpose of establishing a suitable procedure. (auth.)

  3. Cigarette Smoke Cadmium Breakthrough from Traditional Filters: Implications for Exposure

    Science.gov (United States)

    Pappas, R. Steven; Fresquez, Mark R.; Watson, Clifford H.

    2015-01-01

    Cadmium, a carcinogenic metal, is highly toxic to renal, skeletal, nervous, respiratory, and cardiovascular systems. Accurate and precise quantification of mainstream smoke cadmium levels in cigarette smoke is important because of exposure concerns. The two most common trapping techniques for collecting mainstream tobacco smoke particulate for analysis are glass fiber filters and electrostatic precipitators. We observed that a significant portion of total cadmium passed through standard glass fiber filters that are used to trap particulate matter. We therefore developed platinum traps to collect the cadmium that passed through the filters and tested a variety of cigarettes with different physical parameters for quantities of cadmium that passed though the filters. We found less than 1% cadmium passed through electrostatic precipitators. In contrast, cadmium that passed through 92 mm glass fiber filters on a rotary smoking machine was significantly higher, ranging from 3.5% to 22.9% of total smoke cadmium deliveries. Cadmium passed through 44 mm filters typically used on linear smoking machines to an even greater degree, ranging from 13.6% to 30.4% of the total smoke cadmium deliveries. Differences in the cadmium that passed through from the glass fiber filters and electrostatic precipitator could be explained in part if cadmium resides in the smaller mainstream smoke aerosol particle sizes. Differences in particle size distribution could have toxicological implications and could help explain the pulmonary and cardiovascular cadmium uptake in smokers. PMID:25313385

  4. The Effect of Aging and Silanization on the Mechanical Properties of Fumed Silica-based Dental Composite

    Directory of Open Access Journals (Sweden)

    Khaje S

    2015-12-01

    Full Text Available Statement of Problem: Mechanical strength and durability of dental composites are the main topics studied in this field of science today. This study examined fumed silica-based composite as a strong and durable restorative material through flexural and cycling test methods. Objectives: The purpose of this study was to evaluate the effect of silanization, ageing, cycling and hybridizing on mechanical properties of fumed silica-based resin composite. Materials and Methods: Composites were made of light-cured copolymer based on Bisphenol A glycolmethacrylate (Bis-GMA and Triethylene glycoldimethacrylate (TEGDMA at proportion of 50:50 which reinforced by fumed silica filler. For each composite sample, 5 specimen bars were made using Teflon mould (2 x 2 x 25 mm3. The samples with 12 wt% fumed silica (FS were considered as a base line group. The samples were exposed to cyclic cold water (FS-CCW and hot water (FS-CHW. The effect of silanization and adding more filler was studied together with samples containing 12 wt% (FS-S (12, 16 wt% (FS-S (16 and 20 wt% (FS-S (20 fumed silica filler. The filler was silanized with (γ-MPS. The degree of conversion was assessed with Fourier Transform Infra-Red spectroscopy. Flexural properties were evaluated with the Three-Point Bending test. Flexural data were analyzed with Excel software. Hardness was measured with an Atomic Force Microscope (AFM. Results: The degree of conversion of the resin reached 74% within 24 hrs. Salinization allowed more filler to be wetted by resin. Addition of silanized particles from sample FS-S (12 to sample FS-S (20 improved the mechanical strength. Hybridizing fumed silica with nano-silica (FS-N had no significant effect on the strength, but nano-hardness improved greatly. Ageing and cycling had adverse effects on the strength of the sample FS. The flexural strength of FS-CHW was 72% less than FS sample. Conclusions: Sample FS-N with low diluent and filler percentage complied with the

  5. Distillation of cadmium from uranium plutonium cadmium alloy

    Science.gov (United States)

    Kato, Tetsuya; Iizuka, Masatoshi; Inoue, Tadashi; Iwai, Takashi; Arai, Yasuo

    2005-04-01

    Uranium-plutonium alloy was prepared by distillation of cadmium from U-Pu-Cd ternary alloy. The initial ternary alloy contained 2.9 wt% U and 8.7 wt% Pu other than Cd, which were recovered by molten salt electrolysis with liquid Cd cathode. The distillation experiments were conducted in 10 g scale of the initial alloy using a small-scale distillation furnace equipped with an evaporator and a condenser in a vacuum vessel. After distillation at 1073 K, the weight of the residue was in good agreement with that of the loaded actinides, where the content of Cd decreased to less than 0.05 wt%. The uranium-plutonium alloy product was recovered without adhering to the yttria crucible. The cross section of the product was observed using electron probe micro-analyzer and it was found to consist of a dense material. Almost all of the evaporated Cd was recovered in the condenser and so enclosed well in the apparatus.

  6. Dynamic of cadmium accumulation in the internal organs of rats after exposure to cadmium chloride and cadmium sulphide nanoparticules of various sizes

    Directory of Open Access Journals (Sweden)

    Apykhtina O.L.

    2017-06-01

    Full Text Available The article presents the results of study of cadmium accumulation in the internal organs of Wistar rats after prolonged intraperitoneal administration of cadmium chloride and cadmium sulphide nanoparticles of 4-6 nm and 9-11 nm in size in a dose of 0.08 mg /kg/day calculated as cadmium. Toxic effects were evaluated after 30 injections (1.5 months, 60 injections (3 months, and 1.5 months after the exposure has been ceased. The results of the study showed that the most intensive accumulation of cadmium was observed in the kidneys and liver of experimental animals, which is due to the peculiarities of the toxicokinetics and the route of administration of cadmium compounds. In the kidneys, spleen and thymus of animals exposed to cadmium sulphide nanoparticles, a greater concentration of cadmium than in the organs of animals exposed to cadmium chloride was found. Cadmium accumulated more intensively in the spleen after exposure to larger nanoparticles, than in the kidneys and thymus. In the liver, heart, aorta and brain significant accumulation was observed after cadmium chloride exposure.

  7. Exposure to welding fumes increases lung cancer risk among light smokers but not among heavy smokers: evidence from two case–control studies in Montreal

    Science.gov (United States)

    Vallières, Eric; Pintos, Javier; Lavoué, Jérôme; Parent, Marie-Élise; Rachet, Bernard; Siemiatycki, Jack

    2012-01-01

    We investigated relationships between occupational exposure to gas and arc welding fumes and the risk of lung cancer among workers exposed to these agents throughout the spectrum of industries. Two population-based case–control studies were conducted in Montreal. Study I (1979–1986) included 857 cases and 1066 controls, and Study II (1996–2001) comprised 736 cases and 894 controls. Detailed job histories were obtained by interview and evaluated by an expert team of chemist–hygienists to estimate degree of exposure to approximately 300 substances for each job. Gas and arc welding fumes were among the agents evaluated. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of lung cancer using logistic regression, adjusting for smoking history and other covariates. The two studies provided similar results, so a pooled analysis was conducted. Among all subjects, no significant association was found between lung cancer and gas welding fumes (OR = 1.1; 95% CI = 0.9–1.4) or arc welding fumes (OR = 1.0; 95% CI = 0.8–1.2). However, when restricting attention to light smokers, there was an increased risk of lung cancer in relation to gas welding fumes (OR = 2.9; 95% CI = 1.7–4.8) and arc welding fumes (OR = 2.3; 95% CI = 1.3–3.8), with even higher OR estimates among workers with the highest cumulative exposures. In conclusion, there was no detectable excess risk of lung cancer due to welding fumes among moderate to heavy smokers; but among light smokers we found an excess risk related to both types of welding fumes. PMID:23342253

  8. Exposure to welding fumes increases lung cancer risk among light smokers but not among heavy smokers: evidence from two case-control studies in Montreal.

    Science.gov (United States)

    Vallières, Eric; Pintos, Javier; Lavoué, Jérôme; Parent, Marie-Élise; Rachet, Bernard; Siemiatycki, Jack

    2012-08-01

    We investigated relationships between occupational exposure to gas and arc welding fumes and the risk of lung cancer among workers exposed to these agents throughout the spectrum of industries. Two population-based case-control studies were conducted in Montreal. Study I (1979-1986) included 857 cases and 1066 controls, and Study II (1996-2001) comprised 736 cases and 894 controls. Detailed job histories were obtained by interview and evaluated by an expert team of chemist-hygienists to estimate degree of exposure to approximately 300 substances for each job. Gas and arc welding fumes were among the agents evaluated. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of lung cancer using logistic regression, adjusting for smoking history and other covariates. The two studies provided similar results, so a pooled analysis was conducted. Among all subjects, no significant association was found between lung cancer and gas welding fumes (OR = 1.1; 95% CI = 0.9-1.4) or arc welding fumes (OR = 1.0; 95% CI = 0.8-1.2). However, when restricting attention to light smokers, there was an increased risk of lung cancer in relation to gas welding fumes (OR = 2.9; 95% CI = 1.7-4.8) and arc welding fumes (OR = 2.3; 95% CI = 1.3-3.8), with even higher OR estimates among workers with the highest cumulative exposures. In conclusion, there was no detectable excess risk of lung cancer due to welding fumes among moderate to heavy smokers; but among light smokers we found an excess risk related to both types of welding fumes.

  9. A study using different types of fumed silica to modify the flowablity, wettability and surface free energy of a model cohesive powder

    OpenAIRE

    Fitriani, Lili

    2017-01-01

    The objectives of this study were to investigate the improvement on flowability of a model cohesive powder using two different types of fumed silica mixed by the dry coating method “mechanofusion” and to explore the relationship between flowability and surface free energy and/or wettability. The first aim was to find the optimum conditions for improving the flowability of a model cohesive powder, glass microspheres (DMV ~ 3.5 µm), by mechanofusion with fumed silica. Conventional blending usin...

  10. Cadmium exposure induces hematuria in Korean adults

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Seok [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Kim, Myounghee, E-mail: dkkim73@gmail.com [Department of Dental Hygiene, College of Health Science, Eulji University, Gyeonggi-do 461-713 (Korea, Republic of); Lee, Su Mi [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lee, Jung Pyo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Sejoong [Department of Internal Medicine, Seoul National University Bundang Hospital, Gyeonggi-do 463-707 (Korea, Republic of); Joo, Kwon Wook [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lim, Chun Soo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Yon Su; Kim, Dong Ki [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of)

    2013-07-15

    Introduction: Toxic heavy metals have adverse effects on human health. However, the risk of hematuria caused by heavy metal exposure has not been evaluated. Methods: Data from 4701 Korean adults were obtained in the Korean National Health and Nutritional Examination Survey (2008–2010). Blood levels of the toxic heavy metals cadmium, lead, and mercury were measured. Hematuria was defined as a result of ≥+1 on a urine dipstick test. The odds ratios (ORs) for hematuria were measured according to the blood heavy metal levels after adjusting for multiple variables. Results: Individuals with blood cadmium levels in the 3rd and 4th quartiles had a greater OR for hematuria than those in the 1st quartile group: 3rd quartile, 1.35 (1.019–1.777; P=0.037); 4th quartile, 1.52 (1.140–2.017; P=0.004). When blood cadmium was considered as a log-transformed continuous variable, the correlation between blood cadmium and hematuria was significant: OR, 1.97 (1.224–3.160; P{sub trend}=0.005). In contrast, no significant correlations between hematuria and blood lead or mercury were found in the multivariate analyses. Discussion: The present study shows that high cadmium exposure is associated with a risk of hematuria. -- Highlights: • A high level of blood cadmium is associated with a high risk of hematuria. • This correlation is independent of several confounding factors. • Blood levels of lead and mercury are not associated with risk of hematuria. • This is the first study on the correlation between cadmium exposure and hematuria risk.

  11. Copper-cadmium interaction in mice: effects of copper status on retention and distribution of cadmium after cadmium exposure

    International Nuclear Information System (INIS)

    Bourcier, D.R.

    1982-01-01

    The role of increased dietary copper in altering the accumulation of cadmium and other metals in tissues, was investigated. Female Swiss-Webster mice were pretreated with cadmium or copper in drinking water for three weeks prior to cadmium exposure for an additional nine weeks, with sub groups from each dose level receiving Cu additions to the Cd supplemented water. In Cd pretreated animals, a significant decrease was observed in Cd concentrations in liver and kidney when Cu was added to Cd in drinking water. Cadmium levels in soluble protein fractions of liver of animals administered 5 ppm Cd were approximately three fold greater than that for the same Cd dose when Cu was added. The same was the case for the metallothionein-like protein fraction (MTP) of the liver cytosol. In copper pretreated animals similar trends were noted in that brain, spleen, liver (but not kidney) Cd levels were decreased in animals receiving Cu additions to the Cd dose. Increased binding of Cd to the MTP fraction was observed after both in vivo and in vitro exposure of intestinal mucosal cells to cadmium

  12. Genotoxic Effect of Atrazine, Arsenic, Cadmium and Nitrate ...

    African Journals Online (AJOL)

    ATZ), Cadmium (Cd), Arsenic (As) and Nitrate (NO3) have both estrogenic activity and carcinogenic potential. Atrazine has clastogenic effects and may also act as tumor promoter as it induces the aromatase enzyme. Arsenic and Cadmium ...

  13. Uptake of cadmium from hydroponic solutions by willows ( Salix spp ...

    African Journals Online (AJOL)

    Salix integra 'Weishanhu') and Yizhibi (S. integra 'Yizhibi') were chosen as model plants to evaluate their potential for uptake of cadmium from hydroponic culture and relative uptake mechanism. Cadmium uptake showed a linear increase in the ...

  14. Hazards to wildlife from soil-borne cadmium reconsidered

    Science.gov (United States)

    Beyer, W.N.

    2000-01-01

    Cadmium is a toxic element that should be included in environmental risk assessments of contaminated soils. This paper argues, however, that hazards to wildlife from cadmium have often been overstated. The literature contains only meager evidence that wild animals have been seriously harmed by cadmium, even at severely contaminated sites. Although some researchers have reported that wildlife have accumulated concentrations of cadmium in their kidneys that were above suggested injury thresholds, the thresholds may be disputed, since they were well below the World Health Organization criterion of 200 mg/kg (wet weight) of cadmium in the renal cortex for protecting human health. Recent risk assessments have concluded that soil cadmium concentrations less than 1 mg/kg are toxic to soil organisms and wildlife, which implies that background concentrations of cadmium naturally found in soils are hazardous. An examination of the databases used to support these assessments suggested that the toxicity of cadmium has been exaggerated.

  15. The Effects of Cadmium at Low Environmental Concentrations on THP-1 Macrophage Apoptosis

    Science.gov (United States)

    Olszowski, Tomasz; Baranowska-Bosiacka, Irena; Gutowska, Izabela; Piotrowska, Katarzyna; Mierzejewska, Katarzyna; Korbecki, Jan; Kurzawski, Mateusz; Tarnowski, Maciej; Chlubek, Dariusz

    2015-01-01

    Cadmium at environmental concentrations is a risk factor for many diseases, including cardiovascular and neurodegenerative diseases, in which macrophages play an important role. The aim of this study was to evaluate the effects of cadmium at low environmental (nanomolar) concentrations on apoptotic processes in THP-1(acute monocytic leukemia cells line)-derived macrophages, with special focus on mitochondrial events involved. Macrophages were incubated with various cadmium chloride (CdCl2) solutions for 48 h at final concentrations of 5 nM, 20 nM, 200 nM and 2 µM CdCl2. Cell viability was measured using flow cytometry. Flow cytometric measurement (annexin V/FITC (annexin V/fluorescein isothiocyanate) and PI (propidium iodide) double staining) was used to quantify the extent of apoptosis. Fluorescence and confocal microscopy were used for imaging of apoptosis process. Changes in mitochondrial membrane potential were monitored using cytofluorimetry after cell staining with JC-1(5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazol-carbocyane iodide) probe. Mitochondrial ROS (reactive oxygen species) levels were measured cytofluorimetrically after incubation of cells with mitochondrial superoxide indicator (MitoSOX) red fluorescent marker. The mRNA expression of Bcl-2 and Bax was analysed with qRT-PCR. Our study demonstrates that cadmium, even at low environmental concentrations, exerts mitochondrial toxicity in THP-1 macrophages. Forty-eight-hour exposure to very low concentrations reduces cell viability and results in cell death by apoptosis and necrosis. The decrease in mitochondrial membrane potential, increased ROS production, increased Bax and decreased Bcl-2 mRNA expression are mitochondrial events involved in cadmium-induced apoptosis. PMID:26370970

  16. An assessment of the effects of a cadmium discharge ordinance

    International Nuclear Information System (INIS)

    Moser, J.H.; Schultz, J.L.

    1982-01-01

    The problem facing the MMSD was high levels of cadmium in Milorganite fertilizer. The cause was determined to be discharges from industry, primarily electroplaters. The solution was the cooperative development of an ordinance to limit the discharge of cadmium. Because the dischargers acted responsibly to comply with the ordinance, the ordinance succeeded in achieving its objective of significantly reducing the cadmium loading to the municipal sewerage system and subsequently reducing the cadmium concentration in Milorganite fertilizer

  17. Cadmium and Its Neurotoxic Effects

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2013-01-01

    Full Text Available Cadmium (Cd is a heavy metal that has received considerable concern environmentally and occupationally. Cd has a long biological half-life mainly due to its low rate of excretion from the body. Thus, prolonged exposure to Cd will cause toxic effect due to its accumulation over time in a variety of tissues, including kidneys, liver, central nervous system (CNS, and peripheral neuronal systems. Cd can be uptaken from the nasal mucosa or olfactory pathways into the peripheral and central neurons; for the latter, Cd can increase the blood brain barrier (BBB permeability. However, mechanisms underlying Cd neurotoxicity remain not completely understood. Effect of Cd neurotransmitter, oxidative damage, interaction with other metals such as cobalt and zinc, estrogen-like, effect and epigenetic modification may all be the underlying mechanisms. Here, we review the in vitro and in vivo evidence of neurotoxic effects of Cd. The available finding indicates the neurotoxic effects of Cd that was associated with both biochemical changes of the cell and functional changes of central nervous system, suggesting that neurotoxic effects may play a role in the systemic toxic effects of the exposure to Cd, particularly the long-term exposure.

  18. The effect of silica fume on early hydration of white Portland cement via fast field cycling-NMR relaxometry

    Science.gov (United States)

    Badea, Codruţa.; Bede, Andrea; Ardelean, Ioan

    2017-12-01

    Fast Field Cycling (FFC) nuclear magnetic resonance (NMR) relaxometry is used to monitor the influence introduced on the hydration process by the addition of silica fume in a cement paste mixture, prepared with white Portland cement. The FFC relaxometry technique was implemented due to its sensitivity to a wider range of molecular motions, which gives more information than other relaxometry techniques performed at a fixed frequency. This unique feature of FFC relaxometry allows better separation of the surface and bulk contributions from the global measured relaxation rate. The relaxation process is dominated by the interaction of water protons with the paramagnetic centers located on the surface of cement grains. In the frame of a two-phase exchange model, this allows the monitoring of the influence of an addition of silica fume on the evolution of surface-to-volume ratio during the early hydration stages.

  19. Assessment of the effect of welding fumes on welders' cognitive failure and health-related quality of life.

    Science.gov (United States)

    Rahmani, Abdolrasoul; Golbabaei, Farideh; Dehghan, Somayeh Farhang; Mazlomi, Adel; Akbarzadeh, Arash

    2016-09-01

    This study examined whether cognitive symptoms and health-related quality of life can be affected by welding fume exposure. Participants consisted of welders (n = 40) and welder assistants (n = 25) from welding units as the exposed group, and office workers (n = 44) as the non-exposed group. All participants were studied using ambient air monitoring and two types of questionnaires: the Cognitive Failures Questionnaire (CFQ) and the 36-item Short Form Health Survey (SF-36). Welders and welder assistants were exposed to higher concentrations of all airborne metals than office employees, except for aluminum and chromium (p health-related quality of life were not related to the measures of welding fume exposure and further research should be performed to find other influencing factors.

  20. Effects of superglue fuming on materials characterization of zip-lock polyethylene bags for route forensic analyses

    International Nuclear Information System (INIS)

    Koester, C.J.; Grant, P.M.; Blankenship, J.F.

    2013-01-01

    Using cyanoacrylate or 'superglue' fuming to develop latent dermatoglyphic prints significantly altered the volatile and semivolatile compounds within the material of polyethylene zip-lock bags. Comparisons of SPME-GC/MS analyses of poly bags obtained before and after application of a glue fuming fingermark-developing technique resulted in markedly different material profiles of the bags. Not only were species added to the chemical composition of a bag, but other compounds that had been initially present were removed. These effects are particularly important for nuclear forensic investigations in the realm of route (pathway) analyses, and may also be of general interest to criminalistics laboratories that examine illicit drugs and their packaging. (author)

  1. The determination of cadmium in sulphide materials

    International Nuclear Information System (INIS)

    Solomons, M.

    1986-01-01

    A spectrophotometric method was developed for the determination of cadmium in sulphide materials containing up to 200 mg of copper, iron, lead, or zinc individually or 100 mg of each of these four elements in admixture. In the method, an initial liquid-liquid extraction of cadmium from the matrix into a solution of tri-n-octylamine in benzene is followed by stripping into nitric acid. The cadmium is measured spectrophotometrically as the dithizone complex in chloroform at 518 nm. For a sample of 0,5 g, the range of the method is 2 to 24 μg of cadmium per gram of sample. The relative standard deviation and accuracy of the method were determined on a reference material of lead concentrate with a certified lead content of 64 per cent and cadmium content of 143 +- 5 μg/g (95 per cent confidence level). The accuracy of the method was found to be about 97 per cent, and the relative standard deviation was 0,018

  2. Gene expression and pathway analysis of human hepatocellular carcinoma cells treated with cadmium.

    Science.gov (United States)

    Cartularo, Laura; Laulicht, Freda; Sun, Hong; Kluz, Thomas; Freedman, Jonathan H; Costa, Max

    2015-11-01

    Cadmium (Cd) is a toxic and carcinogenic metal naturally occurring in the Earth's crust. A common route of human exposure is via diet and cadmium accumulates in the liver. The effects of Cd exposure on gene expression in human hepatocellular carcinoma (HepG2) cells were examined in this study. HepG2 cells were acutely-treated with 0.1, 0.5, or 1.0 μM Cd for 24h; or chronically-treated with 0.01, 0.05, or 0.1 μM Cd for three weeks and gene expression analysis was performed using Affymetrix GeneChip® Human Gene 1.0 ST Arrays. Acute and chronic exposures significantly altered the expression of 333 and 181 genes, respectively. The genes most upregulated by acute exposure included several metallothioneins. Downregulated genes included the monooxygenase CYP3A7, involved in drug and lipid metabolism. In contrast, CYP3A7 was upregulated by chronic Cd exposure, as was DNAJB9, an anti-apoptotic J protein. Genes downregulated following chronic exposure included the transcriptional regulator early growth response protein 1. Ingenuity Pathway Analysis revealed that the top networks altered by acute exposure were lipid metabolism, small molecule biosynthesis, cell morphology, organization, and development; while top networks altered by chronic exposure were organ morphology, cell cycle, cell signaling, and renal and urological diseases/cancer. Many of the dysregulated genes play important roles in cellular growth, proliferation, and apoptosis, and may be involved in carcinogenesis. In addition to gene expression changes, HepG2 cells treated with cadmium for 24h indicated a reduction in global levels of histone methylation and acetylation that persisted 72 h post-treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Effects of ginger ( Zingiber officinale ) on cadmium toxicity ...

    African Journals Online (AJOL)

    transaminase (GOT) and glutamate pyruvate transaminase (GPT), while ginger lowered these parameters. Ginger had better therapeutic than prophylactic detoxication effects on liver cadmium accumulation, especially as further cadmium intake was stopped. It was concluded that cadmium detoxication by ginger was more ...

  4. Uptake of cadmium from hydroponic solutions by willows (Salix spp ...

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2011-11-16

    Nov 16, 2011 ... active absorption and passive absorption occurred in the cadmium uptake by willow roots. Key words: Cadmium ... as biological filter. These traits make it a potential ideal candidate for phytoremediation of cadmium contaminated waters and soils. Dickinson and Pulford, (2005) also reported that willow is a ...

  5. Effect of Low Level Cadmium Exposure on Superoxide Dismutase ...

    African Journals Online (AJOL)

    The data showed a negative correlation between tissue cadmium and SOD in plasma, erythrocyte and brain. While positive associations were observed between blood and tissue (brain and liver) cadmium and SOD, a significant (p < 0.01), negative correlation was found between tissue cadmium and SOD. Conclusion: As ...

  6. Cadmium affects the social behaviour of rainbow trout, Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Sloman, Katherine A.; Scott, Graham R.; Diao Zhongyu; Rouleau, Claude; Wood, Chris M.; McDonald, D. Gord

    2003-10-29

    The present study investigated both the effects of cadmium on the social interactions of rainbow trout and the differential accumulation of waterborne cadmium among social ranks of fish. Fish exposed to waterborne cadmium concentrations of 2 {mu}g l{sup -1} for 24 h, followed by a 1, 2 or 3 day depuration period in clean water, had a decreased ability to compete with non-exposed fish. However, the competitive ability of exposed fish given a 5 day depuration period was not significantly impaired. Cadmium accumulated in the olfactory apparatus of fish exposed to waterborne cadmium for 24 h and decreased significantly only after 5 days depuration in clean water. Among groups of ten fish held in stream tanks, where all fish were exposed to cadmium, there were significant effects on social behaviour and growth rate. Dominance hierarchies formed faster among fish exposed to cadmium than among control fish, and overall growth rates were higher in the cadmium treatment. In groups of ten fish, social status also affected tissue accumulation of cadmium during waterborne exposure, with dominant fish accumulating more cadmium at the gill. In conclusion, exposure to low levels of cadmium, affects the social behaviour of fish, in part due to accumulation in the olfactory apparatus, and dominant fish accumulate more gill cadmium than subordinates during chronic waterborne exposure.

  7. Cadmium affects the social behaviour of rainbow trout, Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Sloman, Katherine A.; Scott, Graham R.; Diao Zhongyu; Rouleau, Claude; Wood, Chris M.; McDonald, D. Gord

    2003-01-01

    The present study investigated both the effects of cadmium on the social interactions of rainbow trout and the differential accumulation of waterborne cadmium among social ranks of fish. Fish exposed to waterborne cadmium concentrations of 2 μg l -1 for 24 h, followed by a 1, 2 or 3 day depuration period in clean water, had a decreased ability to compete with non-exposed fish. However, the competitive ability of exposed fish given a 5 day depuration period was not significantly impaired. Cadmium accumulated in the olfactory apparatus of fish exposed to waterborne cadmium for 24 h and decreased significantly only after 5 days depuration in clean water. Among groups of ten fish held in stream tanks, where all fish were exposed to cadmium, there were significant effects on social behaviour and growth rate. Dominance hierarchies formed faster among fish exposed to cadmium than among control fish, and overall growth rates were higher in the cadmium treatment. In groups of ten fish, social status also affected tissue accumulation of cadmium during waterborne exposure, with dominant fish accumulating more cadmium at the gill. In conclusion, exposure to low levels of cadmium, affects the social behaviour of fish, in part due to accumulation in the olfactory apparatus, and dominant fish accumulate more gill cadmium than subordinates during chronic waterborne exposure

  8. Bioaccumulation of cadmium in the ascidian Styela clava (Herdman ...

    African Journals Online (AJOL)

    The high rate of accumulation and elimination of cadmium from the body reveals the potential of the organism to be used as a biomonitor of short-term cadmium fluctuation in marine systems. Keywords: accumulation;, cadmium; elimination; kinetics; Styela clava. African Journal of Marine Science 2009, 31(3): 289–295 ...

  9. Cadmium recycling in the United States in 2000

    Science.gov (United States)

    Plachy, Jozef

    2003-01-01

    Recycling of cadmium is a young and growing industry that has been influenced by environmental concerns and regulatory constraints. Domestic recycling of cadmium began in 1989 as a byproduct of processing of spent nickel-cadmium batteries. In 1995, International Metals Reclamation Co. Inc. expanded its operations by building a dedicated cadmium recycling plant. In 2000, an estimated 13 percent of cadmium consumption in the United States was sourced from recycled cadmium, which is derived mainly from old scrap or, to lesser degree, new scrap. The easiest forms of old scrap to recycle are small spent nickel-cadmium batteries followed by flue dust generated during recycling of galvanized steel and small amounts of alloys that contain cadmium. Most of new scrap is generated during manufacturing processes, such as nickel-cadmium battery production. All other uses of cadmium are in low concentrations and, therefore, difficult to recycle. Consequently, much of this cadmium is dissipated and lost. The amount of cadmium in scrap that was unrecovered in 2000 was estimated to be 2,030 metric tons, and an estimated 285 tons was recovered. Recycling efficiency was estimated to be about 15 percent.

  10. Determination and estimation of Cadmium intake from Tarom rice ...

    African Journals Online (AJOL)

    Cadmium (Cd) is one of the most well-known environmental intoxicants to humans. Its entrance to food chain causes the serious damage in humans. One of the major sources of Cadmium intake is rice for rice eating countries such as Iran. Cadmium in rice comes from soil through plant roots. Thus, Rice may be the best ...

  11. Cadmium uptake by the green alga Chlorella emersonii | Arikpo ...

    African Journals Online (AJOL)

    Investigations were carried out on the uptake of the heavy metal cadmium (Cd) by the green alga Chlorella emersonii with the aid of an ion selective electrode. Cadmium uptake by Chlorella was very rapid with 70% of total uptake occurring during the first 10 seconds. Uptake of cadmium by Chlorella showed a direct ...

  12. Cadmium-113m as a biogeochemical tracer for cadmium in Lake Michigan

    International Nuclear Information System (INIS)

    Dunn, D.L.

    1987-01-01

    The Lake Michigan watershed has been sampled for 113m Cd. This long-lived metastable isotope of cadmium allowed independent evaluation of cadmium distribution in this dynamic ecosystem. 113m Cd analysis was not hampered by contamination or loss. These are problems which have plagued stable cadmium measurements. Sensitivity and specificity were necessary concerns. 113m Cd has been preconcentrated from large samples in order to obtain sufficient activity for quantification. Specificity for the gross beta activity measured was secured in a rigorous ion exchange decontamination. Confirmation of the suspected 113m Cd beta source was checked by reverse tracer analysis and modified Feather analysis range-energy relationships. The 113m Cd activities confirm the expected semiconservative behavior for cadmium. This behavior manifests itself in a long residence time for cadmium in Lake Michigan. The inefficiency of outflow removal, the low sedimentation rate and the unquantified sediment resuspension and release of cadmium are factors contributing to this residence time. Steady state concentration of cadmium in Lake Michigan will increase if present input rates persist

  13. Exposure to welding fumes is associated with hypomethylation of the F2RL3 gene: a cardiovascular disease marker.

    Science.gov (United States)

    Hossain, Mohammad B; Li, Huiqi; Hedmer, Maria; Tinnerberg, Håkan; Albin, Maria; Broberg, Karin

    2015-12-01

    Welders are at risk for cardiovascular disease. Recent studies linked tobacco smoke exposure to hypomethylation of the F2RL3 (coagulation factor II (thrombin) receptor-like 3) gene, a marker for cardiovascular disease prognosis and mortality. However, whether welding fumes cause hypomethylation of F2RL3 remains unknown. We investigated 101 welders (median span of working as a welder: 7 years) and 127 unexposed controls (non-welders with no obvious exposure to respirable dust at work), age range 23-60 years, all currently non-smoking, in Sweden. The participants were interviewed about their work history, lifestyle factors and diseases. Personal sampling of respirable dust was performed for the welders. DNA methylation of F2RL3 in blood was assessed by pyrosequencing of four CpG sites, CpG_2 (corresponds to cg03636183) to CpG_5, in F2RL3. Multivariable linear regression analysis was used to assess the association between exposure to welding fumes and F2RL3 methylation. Welders had 2.6% lower methylation of CpG_5 than controls (pWelding fumes exposure and previous smoking were associated with F2RL3 hypomethylation. This finding links low-to-moderate exposure to welding fumes to adverse effects on the cardiovascular system, and suggests a potential mechanistic pathway for this link, via epigenetic effects on F2RL3 expression. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  14. A comparative study of the effects of silica fume, metakaolin and pfa on the air content of fresh concrete

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, G. [University of Glamorgan, Pontypridd (United Kingdom). School of Technology

    2000-07-01

    This paper examines the influence of admixture doses on the air content of the fresh concrete in relation to various partial replacement levels of Portland cement by condensed silica fume (CSF) metakaolin (MK) or pulverised fuel ash (PFA). The findings of a study of the interrelationships between the effects of a recently developed highly efficient superplasticiser (HRWRA) and air entraining admixture on the workability and air content in concrete containing CSF, MK or PFA are given. 30 refs., 8 figs., 5 tabs.

  15. Effect of Oil Paint Fumes Inhalation on the Level of Serum Thyroid Hormones and Thyroid Stimulating Hormone in Rats

    Directory of Open Access Journals (Sweden)

    M. Siavashi

    2016-09-01

    Full Text Available Aims: The exposure to chemical materials and colors affects thyroid gland functions. The aim of this study was to investigate the effects of fume inhalation of oil-based paints on the serum level of thyroid hormones in female and male rats. Materials & Methods: In the experimental study, 15 male and 15 female Wistar rats were studied. The rats were divided into six 5-rat groups including a control group and groups with either 1- or 8-hour a day exposure to the paint fumes by gender division. The serum levels of T3, T4, and TSH thyroid hormones were measured after 10 weeks. Data was analyzed by SPSS 20 software using two-way ANOVA and Tukey’s post-hoc. Findings: Mean values of T3 and T4 hormones were significantly reduced in both 1- and 8-hour male and female groups than control group (p<0.001. In addition, the more the inhalation time, the more the reduction was. Any reduction in T3 in females in 1-hour (p<0.001 and 8–hour (p<0.05 groups was significantly more than the males. Nevertheless, a significant reduction in T4 was only in 1-hour group (p<0.001. Mean TSH hormone was significantly increased due to the inhalation of paint fume than control group (p<0.001. In addition, such an increase was significant in the female rats in 8-hour group than the male group (p<0.01. Conclusion: The inhalation of oil-based paint fume leads to a reduction in the serum levels of T3 and T4 thyroid hormones, while increases TSH serum level. Such an effect is stronger in the females.

  16. Ribosomal genes as early targets of cadmium-induced toxicity in Chironomus riparius larvae

    Energy Technology Data Exchange (ETDEWEB)

    Planello, R. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain); Martinez-Guitarte, J.L. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain); Morcillo, G. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain)]. E-mail: gmorcillo@ccia.uned.es

    2007-02-01

    Cadmium is a widespread environmental pollutant that causes severe impacts in organisms. Although the effects of cadmium on aquatic insects have been studied in terms of their toxicity and changes in developmental parameters, little is known about its molecular and genetic effects. We have investigated the alterations in the pattern of gene expression provoked by acute exposure to cadmium in Chironomus riparius Mg. (Diptera, Chironomidae), a sentinel organism widely used in aquatic toxicity testing. The early cytotoxic effects were evaluated using immunocytochemistry and specific fluorescent probes in fourth instar larvae after 12 h of 10 mM cadmium treatments; under these conditions no significant effect on larvae mortality was detected until after 36 h of exposure. The changes in the pattern of gene expression were analysed by means of DNA/RNA hybrid antibodies in the polytene chromosomes from salivary gland cells. A decrease in the activity of the nucleolus is especially remarkable, accompanied by a significant reduction in size and the modification in nucleolar architecture, as shown by FISH. The inhibition of rDNA transcription was further evaluated by Northern blot analysis, which showed a marked decrease in the level of preribosomal rRNA (54% 45S 12 h). However, the BR genes, whose products are the giant polypeptides that constitute the silk-like secretion for constructing housing tubes, remain active. Simultaneously, decondensation and activation take place at some chromosomal regions, especially at the centromeres. The changes observed in the pattern of gene expression do not resemble those found after heat shock or other cell stressors. These data provide the first evidence that cadmium interacts with ribosomal genes and results in a drastic impairment of the functional activity of the nucleolus, an essential organelle for cellular survival. Therefore, the depletion of ribosomes would be a long-term effect of Cd-induced cellular damage. These findings may

  17. Ribosomal genes as early targets of cadmium-induced toxicity in Chironomus riparius larvae

    International Nuclear Information System (INIS)

    Planello, R.; Martinez-Guitarte, J.L.; Morcillo, G.

    2007-01-01

    Cadmium is a widespread environmental pollutant that causes severe impacts in organisms. Although the effects of cadmium on aquatic insects have been studied in terms of their toxicity and changes in developmental parameters, little is known about its molecular and genetic effects. We have investigated the alterations in the pattern of gene expression provoked by acute exposure to cadmium in Chironomus riparius Mg. (Diptera, Chironomidae), a sentinel organism widely used in aquatic toxicity testing. The early cytotoxic effects were evaluated using immunocytochemistry and specific fluorescent probes in fourth instar larvae after 12 h of 10 mM cadmium treatments; under these conditions no significant effect on larvae mortality was detected until after 36 h of exposure. The changes in the pattern of gene expression were analysed by means of DNA/RNA hybrid antibodies in the polytene chromosomes from salivary gland cells. A decrease in the activity of the nucleolus is especially remarkable, accompanied by a significant reduction in size and the modification in nucleolar architecture, as shown by FISH. The inhibition of rDNA transcription was further evaluated by Northern blot analysis, which showed a marked decrease in the level of preribosomal rRNA (54% 45S 12 h). However, the BR genes, whose products are the giant polypeptides that constitute the silk-like secretion for constructing housing tubes, remain active. Simultaneously, decondensation and activation take place at some chromosomal regions, especially at the centromeres. The changes observed in the pattern of gene expression do not resemble those found after heat shock or other cell stressors. These data provide the first evidence that cadmium interacts with ribosomal genes and results in a drastic impairment of the functional activity of the nucleolus, an essential organelle for cellular survival. Therefore, the depletion of ribosomes would be a long-term effect of Cd-induced cellular damage. These findings may

  18. An Accelerated Test Method of Simultaneous Carbonation and Chloride Ion Ingress: Durability of Silica Fume Concrete in Severe Environments

    Directory of Open Access Journals (Sweden)

    S. A. Ghahari

    2016-01-01

    Full Text Available The effects of simultaneous carbonation and chloride ion attack on mechanical characteristics and durability of concrete containing silica fume have been investigated through an accelerated test method. Specimens containing different amounts of silica fume were maintained in an apparatus in which carbon dioxide pressure and concentration and relative humidity were kept constant, and wetting and drying cycles in saline water were applied. Surface resistivity, sorptivity, CO2 consumption, and carbonation and chloride ion ingress depths measurements were taken. Phase change due to carbonation and chloride ion attack was monitored by XRD analysis, and microstructures and interfacial transition zones were studied by implementing SEM as well as mercury intrusion porosimetry. It was expected to have a synergistic effect in the tidal zone where simultaneous carbonation and chloride ion attack happen. However, the observed reduced surface resistivity, compared to specimens maintained in CO2 gas, could be due to the moisture that is available near the surface, hindering CO2 from penetrating into the pores of the specimens. Moreover, the porosity analysis of the specimens showed that the sample containing silica fume cured in the tidal zone had 50.1% less total porosity than the plain cement paste cured in the same condition.

  19. A Scanning Transmission Electron Microscopy Method for Determining Manganese Composition in Welding Fume as a Function of Primary Particle Size.

    Science.gov (United States)

    Richman, Julie D; Livi, Kenneth J T; Geyh, Alison S

    2011-06-01

    Increasing evidence suggests that the physicochemical properties of inhaled nanoparticles influence the resulting toxicokinetics and toxicodynamics. This report presents a method using scanning transmission electron microscopy (STEM) to measure the Mn content throughout the primary particle size distribution of welding fume particle samples collected on filters for application in exposure and health research. Dark field images were collected to assess the primary particle size distribution and energy-dispersive X-ray and electron energy loss spectroscopy were performed for measurement of Mn composition as a function of primary particle size. A manual method incorporating imaging software was used to measure the primary particle diameter and to select an integration region for compositional analysis within primary particles throughout the size range. To explore the variation in the developed metric, the method was applied to 10 gas metal arc welding (GMAW) fume particle samples of mild steel that were collected under a variety of conditions. The range of Mn composition by particle size was -0.10 to 0.19 %/nm, where a positive estimate indicates greater relative abundance of Mn increasing with primary particle size and a negative estimate conversely indicates decreasing Mn content with size. However, the estimate was only statistically significant (psize among welding fume samples can be detected.

  20. Cadmium in the shore crab Carcinus maenas: seasonal variation in cadmium content and uptake and elimination of cadmium after administration via food

    International Nuclear Information System (INIS)

    Bjerregaard, Poul; Bjorn, Lars; Norum, Ulrik; Pedersen, Knud L.

    2005-01-01

    The uptake and assimilation efficiency of cadmium administered via the food in the shore crab Carcinus maenas were investigated together with elimination kinetics and seasonal variations in cadmium content. The majority of shore crabs assimilated between 41 and 86% of the cadmium administered in their food. More than 90% of the cadmium taken up from food was retained in midgut gland. Elimination of cadmium after uptake from one meal of radioactively labelled soft parts of blue mussels could be described by a three-compartment model (percent 109 Cd-retained = 64 x e -0.001107 xt + 25 x e -0.0385 xt + 11 x e -0.888 xt ). The biological half-life for cadmium in the most slowly exchanging compartment (containing 64% of the body burden) was 626 days. Groups of male and female shore crabs were collected from an uncontaminated site in the period May till October and the concentrations of cadmium in midgut gland and gills were determined. Male crabs had higher cadmium concentrations in the midgut gland in June and August (mean 2.7 μg Cd g -1 dry weight) than they had in May, September and October (mean 1.7 μg Cd g -1 dry weight). Females generally had slightly lower cadmium concentrations in the midgut gland than the males, except for a relatively high concentration in May. The cadmium concentrations in gills generally ranged between 0.3 and 0.5 μg Cd g -1 dry weight) except for male values in October (mean 1 μg Cd g -1 dry weight). Some of the seasonal changes in cadmium content of the crabs might plausibly be explained by changes in cadmium uptake from water, i.e. changes during the moult cycle and changes in cadmium uptake rates from water brought about by changes in ambient factors such as salinity and temperature. However, uptake of cadmium from water and transfer to the midgut gland take place at a rate that is two orders of magnitude too low to account for the increase in the cadmium concentrations in midgut gland in male crabs between May and June. The

  1. Cadmium accumulation by Axonopus compressus (Sw. P. Beauv and Cyperus rotundas Linn growing in cadmium solution and cadmium-zinc contaminated soil

    Directory of Open Access Journals (Sweden)

    Paitip Thiravetyan

    2007-05-01

    Full Text Available This research investigated the phyto-remediation potentials of Cyperus rotundas Linn (Nutgrass and Axonopus compressus (Sw. P. Beauv (Carpetgrass for cadmium removal from cadmium solution andcadmium-zinc contaminated soil. Plants growth in the solution showed that cadmium decreased the relative growth rate of both grasses. However, the amount of cadmium accumulated in shoot and root was increasedwith the increase in cadmium concentration and exposure time. Growth in fertile soil mixed with Cd-contaminated zinc silicate residue (65% Si, 19% Ca, 2% Zn, 1% Mg and 0.03% Cd at the ratio of 50:50 (w/wfor 30 days showed that C. rotundas Linn accumulated cadmium in root and shoot to 2,178 and 1,144 mg kg-1 dry weight, respectively. A. compressus (Sw. P. Beauv accumulated cadmium in root and shoot to 1,965and 669 mg kg-1 dry weight, respectively. Scanning electron microscope connected to energy-dispersive X-ray spectroscopy suggested that the mechanism of cadmium accumulation by both grasses involved thecadmium precipitation in the stable form of cadmium silicate, which indicated that C. rotundas Linn and A. compressus (Sw. P. Beauv could be grown to prevent soil erosion and to remediate cadmium-contaminatedsoil.

  2. Analysis of cadmium in high alpha solutions

    International Nuclear Information System (INIS)

    Gray, L.W.; Overman, L.A.; Hodgens, H.F.

    1977-07-01

    Cadmium nitrate is occasionally used as a neutron poison for convenience in the separation of uranium, neptunium, and plutonium. As the classical methods of analysis for cadmium are very time-consuming, a method to isolate it in solution using solvent extraction of uranium, neptunium, and plutonium with TBP in an n-paraffin hydrocarbon was investigated. After removal of the radionuclides, the cadmium is determined by atomic absorption spectroscopy. Precision of the method at the 95 percent confidence level is +-2.4 percent. Alpha content of the solutions was typically reduced from 1-10 x 10 11 dis/(min ml) 238 Pu to 1-15 x 10 4 dis/(min ml). Analysis time was typically reduced from approximately 24 hours per sample to less than 1 hour

  3. Bireactor Electronuclear Systems with Liquid Cadmium Valve

    CERN Document Server

    Bznuni, S A; Zhamkochyan, V M; ASosnin, A N; Polanski, A; Khudaverdyan, A H

    2002-01-01

    Three main types of bireactor electronuclear systems are discussed. From the point of view of assuring high level of functional characteristics and safety bireactor electronuclear systems with booster using enriched uranium (20 %) and with a liquid cadmium valve appears to be the most effective. It is shown by means of Monte-Carlo modeling that such operation conditions can be achieved which lead to the destruction of the intermediate cadmium layer making the systems supercritical (k_{eff}>1). One can avoid the problem by using a special design of the liquid cadmium valve. In comparison with other nuclear systems (critical reactors, one-reactor electronuclear systems) cascade electronuclear systems have essential advantages allowing the decrease of the proton beam current by one order of magnitude and providing at same time the necessary level of power generation and neutron flux. Availability of both the thermal and fast cones allows one to transmute not only transuranics but also the fission products - cesi...

  4. ELECTROKINETIC REMEDIATION STUDY FOR CADMIUM CONTAMINATED SOIL

    Directory of Open Access Journals (Sweden)

    P. Bala Ramudu

    2007-09-01

    Full Text Available This paper presents the results of an experimental research undertaken to evaluate different purging solutions to enhance the removal of cadmium from spiked contaminated field soil by electrokinetic remediation. Three experiments were conducted when soil was saturated with deionised water and subsequently deionised water, ammonium citrate and sodium citrate were used as purging solutions at anode end. One experiment was conducted when the soil was saturated with ammonium citrate and itself was used as the purging solution. Results showed that 49% reduction of cadmium concentration was achieved in the case of soil saturated (washed with ammonium citrate as well as purging solution also was ammonium citrate. The soil pH and washing solutions were the most important factors in controlling the removal of cadmium in electrokinetic remediation process.

  5. Exposure to diesel exhaust fumes in the context of exposure to ultrafine particles

    Directory of Open Access Journals (Sweden)

    Stella Bujak-Pietrek

    2016-08-01

    Full Text Available Objectives: Diesel exhaust fumes emission is a significant source of ultrafine particles, the size of which is expressed in nanometers. People occupationally exposed to diesel exhaust particles include mainly workers servicing vehicles with engines of this type. This article presents the analysis of measurements of ultrafine particle concentrations occurring in the bus depot premises during the work connected with everyday technical servicing of buses. Material and Methods: The measurements were carried out in the everyday servicing (ES room of the bus depot before, during and after the work connected with bus servicing. Determinations included: particle concentrations in terms of particle number and particle surface area, and mass concentrations of aerosol. Results: Mean value of number concentration of 10- to 1000-nm particles increased almost 20-fold, from 7600 particles/cm3 before starting bus servicing procedures to 130 000 particles/cm3 during the bus servicing procedures in the room. During the procedures, the mean surface area concentration of particles potentially deposited in the alveolar (A region was almost 3 times higher than that of the particles depositing in the tracheo-bronchial (TB region: 356.46 μm2/cm3 vs. 95.97 μm2/cm3, respectively. The mass concentration of the fraction of particulate matter with aerodynamic diameter 0.02–1 μm (PM1 increased 5-fold during the analyzed procedures and was 0.042 mg/m3 before, and 0.298 mg/m3 while the procedures continued. Conclusions: At the time when bus servicing procedures continued in the ES room, a very high increase in all parameters of the analyzed particles was observed. The diesel exhaust particles exhibit a very high degree of fragmentation and, while their number is very high and their surface area is very large, their mass concentration is relatively low. The above findings confirm that ultrafine particles found in diesel exhaust fumes may be harmful to the health of the

  6. Reduction of Cadmium Uptake of Rice Plants Using Soil Amendments in High Cadmium Contaminated Soil: A Pot Experiment

    Directory of Open Access Journals (Sweden)

    Dian Siswanto

    2013-05-01

    Full Text Available The aims of this study were to investigate the effect of agricultural residues on reducing cadmium uptake in rice plants. The rice plants growing on no cadmium/free cadmium soils (N, Cd soils (Cds, and Cd soils each amended with 1% w/w of coir pith (CP, coir pith modified with sodium hydroxide (CPm and corncob (CC under high cadmium contaminated soil with an average 145 mg Cd kg-1 soil were investigated. The results showed that the cumulative transpiration of rice grown in various treatments under high cadmium contaminated soil followed the order: Cds > CPm ≥ CP ≥ CC. These transpirations directly influenced cadmium accumulation in shoots and husks of rice plants. The CC and CP seemed to work to reduce the cadmium uptake by rice plants indicated by accumulated cadmium in the husk that were 2.47 and 7.38 mg Cd kg-1 dry weight, respectively. Overall, transpiration tended to drive cadmium accumulation in plants for rice grown in high cadmium contaminated soil. The more that plants uptake cadmium, the lower cadmium that remains in the soil.

  7. Acute pancreatitis

    Science.gov (United States)

    ... its blood vessels. This problem is called acute pancreatitis. Acute pancreatitis affects men more often than women. Certain ... well it can be treated. Complications of acute pancreatitis may include: Acute kidney failure Long-term lung damage (ARDS) Buildup ...

  8. Potentiating effects of oxygen in lungs damaged by methylcyclopentadienyl manganese tricarbonyl, cadmium chloride, oleic acid, and antitumor drugs

    Energy Technology Data Exchange (ETDEWEB)

    Hakkinen, P.J.; Morse, C.C.; Martin, F.M.; Dalbey, W.E.; Haschek, W.M.; Witschi, H.R.

    1983-01-01

    The intraperitoneal administration of methylcyclopentadienyl manganese tricarbonyl (MMT) and cyclophosphamide, exposure to an aerosol of cadmium chloride, intravenous administration of oleic acid, and intratracheal instillation of bleomycin to young female BALB/c mice or CD/CR rats result in acute lung injury. Pulmonary morphology and lung collagen content were examined in animals treated with these chemicals alone or in combination with an elevated oxygen concentration (80%) in the inspired air. In mice, the development of fibrosis could be significantly enhanced if animals treated with MMT, cadmium chloride, cyclophosphamide, or bleomycin were exposed to 80% oxygen immediately following exposure to these agents. In rats only cyclophosphamide- and bleomycin-induced acute lung injury was potentiated by hyperoxia, resulting in significant enhancement of lung collagen content. The pathogenesis responsible for this differential species response of pulmonary injury to hyperoxia remains to be investigated.

  9. Environmental cadmium and breast cancer risk

    OpenAIRE

    Gallagher, Carolyn M.; Chen, John J.; Kovach, John S.

    2010-01-01

    Breast cancer is the most prevalent women's cancer, with an age-adjusted incidence of 122.9 per 100,000 US women. Cadmium, a ubiquitous carcinogenic pollutant with multiple biological effects, has been reported to be associated with breast cancer in one US regional case-control study. We examined the association of breast cancer with urinary cadmium (UCd), in a case-control sample of women living on Long Island (LI), NY (100 with breast cancer and 98 without), a region with an especially high...

  10. Cadmium telluride quantum dots advances and applications

    CERN Document Server

    Donegan, John

    2013-01-01

    Optical Properties of Bulk and Nanocrystalline Cadmium Telluride, Núñez Fernández and M.I. VasilevskiyAqueous Synthesis of Colloidal CdTe Nanocrystals, V. Lesnyak, N. Gaponik, and A. EychmüllerAssemblies of Thiol-Capped CdTe Nanocrystals, N. GaponikFörster Resonant Energy Transfer in CdTe Nanocrystal Quantum Dot Structures, M. Lunz and A.L. BradleyEmission of CdTe Nanocrystals Coupled to Microcavities, Y.P. Rakovich and J.F. DoneganBiological Applications of Cadmium Telluride Semiconductor Quantum Dots, A. Le Cign

  11. Mineral resource of the month: cadmium

    Science.gov (United States)

    Tolcin, Amy C.

    2012-01-01

    The element cadmium was discovered in 1817 by Friedrich Stromeyer, a professor of chemistry at the University of Göttingen in Germany. Stromeyer noticed that a yellowish glow would occur when heat was applied to certain samples of calamine, a zinc-carbonate. This was unusual as the reaction was expected to be colorless. After further testing, Stromeyer deduced that an unknown metallic impurity in the carbonate caused the color change. He called the new metal "cadmium" after "kadmeia," the Greek word for calamine.

  12. Elektrokemisk fjernelse af cadmium fra bioasker

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Simonsen, Peter

    Posteren viser resultater fra elektrokemiske rensningsforsøg på bioasker udført i forbindelse med PSO projekt 5205 "Elektrokemisk fjernelse af cadmium fra bioasker i pilotskala og vurdering af mulighederne for nyttiggørelse af behandlet aske i beton".......Posteren viser resultater fra elektrokemiske rensningsforsøg på bioasker udført i forbindelse med PSO projekt 5205 "Elektrokemisk fjernelse af cadmium fra bioasker i pilotskala og vurdering af mulighederne for nyttiggørelse af behandlet aske i beton"....

  13. Cadmium toxicity in the free-living nematode, Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Popham, J.D.; Webster, J.M.

    1979-10-01

    The effect of cadmium on the fecundity, growth, and fine structure of the free-living nematode Caenorhabditis elegans was studied. High concentrations of cadmium significantly decreased the fecundity and growth of these organisms. Electron microscopy showed that cadmium modifies the structure of the mitochondria in the esophagus and intestine, causes the formation of inclusion bodies in the nucleus of esophageal cells, and alters the morphology of cytosomes in the intestinal cells. The results suggest that the decreased fecundity and growth of cadmium-exposed C. elegans may be due to cadmium interfering with nutrient uptake or assimilation or both.

  14. Fuel conditioning facility electrorefiner cadmium vapor trap operation

    International Nuclear Information System (INIS)

    Vaden, D. E.

    1998-01-01

    Processing sodium-bonded spent nuclear fuel at the Fuel Conditioning Facility at Argonne National Laboratory-West involves an electrometallurgical process employing a molten LiCl-KCl salt covering a pool of molten cadmium. Previous research has shown that the cadmium dissolves in the salt as a gas, diffuses through the salt layer and vaporizes at the salt surface. This cadmium vapor condenses on cool surfaces, causing equipment operation and handling problems. Using a cadmium vapor trap to condense the cadmium vapors and reflux them back to the electrorefiner has mitigated equipment problems and improved electrorefiner operations

  15. Altered ion transport in normal human bronchial epithelial cells following exposure to chemically distinct metal welding fume particles.

    Science.gov (United States)

    Fedan, Jeffrey S; Thompson, Janet A; Meighan, Terence G; Zeidler-Erdely, Patti C; Antonini, James M

    2017-07-01

    Welding fume inhalation causes pulmonary toxicity, including susceptibility to infection. We hypothesized that airway epithelial ion transport is a target of fume toxicity, and investigated the effects of fume particulates from manual metal arc-stainless steel (MMA-SS) and gas metal arc-mild steel (GMA-MS) on ion transport in normal human bronchial epithelium (NHBE) cultured in air-interface. MMA-SS particles, more soluble than GMA-MS particles, contain Cr, Ni, Fe and Mn; GMA-MS particles contain Fe and Mn. MMA-SS or GMA-MS particles (0.0167-166.7μg/cm 2 ) were applied apically to NHBEs. After 18h transepithelial potential difference (V t ), resistance (R t ), and short circuit current (I sc ) were measured. Particle effects on Na + and Cl¯ channels and the Na + ,K + ,2Cl¯-cotransporter were evaluated using amiloride (apical), 5-nitro-2-[(3-phenylpropyl)amino]benzoic acid (NPPB, apical), and bumetanide (basolateral), respectively. MMA-SS (0.0167-16.7μg/cm 2 ) increased basal V t . Only 16.7μg/cm 2 GMA-MS increased basal V t significantly. MMA-SS or GMA-MS exposure potentiated I sc responses (decreases) to amiloride and bumetanide, while not affecting those to NPPB, GMA-MS to a lesser degree than MMA-SS. Variable effects on R t were observed in response to amiloride, and bumetanide. Generally, MMA-SS was more potent in altering responses to amiloride and bumetanide than GMA-MS. Hyperpolarization occurred in the absence of LDH release, but decreases in V t , R t , and I sc at higher fume particulate doses accompanied LDH release, to a greater extent for MMA-SS. Thus, Na + transport and Na + ,K + ,2Cl¯-cotransport are affected by fume exposure; MMA-MS is more potent than GMA-MS. Enhanced Na + absorption and decreased airway surface liquid could compromise defenses against infection. Published by Elsevier Inc.

  16. Effect of taurine supplementation on hepatic metabolism and alleviation of cadmium toxicity and bioaccumulation in a marine teleost, red sea bream, Pagrus major.

    Science.gov (United States)

    Hano, Takeshi; Ito, Katsutoshi; Kono, Kumiko; Ito, Mana; Ohkubo, Nobuyuki; Mochida, Kazuhiko

    2017-02-01

    This study was performed to unravel the mechanism of the beneficial action of taurine on marine teleost fish, red sea bream (Pagrus major), by analyzing the hepatic metabolism. Moreover, the ameliorative effects of the nutrient against cadmium toxicity and bioaccumulation were further evaluated. The fish were fed a diet containing 0 % (TAU0 %), 0.5 % (TAU0.5 %), or 5.0 % (TAU5.0 %) taurine for 40-55 days (d) and subjected to cadmium acute toxicity and bioaccumulation tests. Taurine deficiency in feed severely affected growth and the hepatic metabolic profiles of the fish, including a remarkable increase in myo-inositol, aspartate, and ß-alanine in the TAU0 % group, which indicates a complementary physiological response to taurine deficiency. For the acute toxicity test, fish were fed the test diets for 55 d and were then exposed to different dose of cadmium ranging from 0 to 5.6 mg/L for 96 h. Fish fed taurine had a higher tolerance to cadmium than those not fed taurine. For the bioaccumulation test, fish were fed the test diets for 40 d and then were chronically exposed to 0.2 mg/L of cadmium for 28 d followed by depuration for 21 d. Cadmium concentrations in the liver and muscle of fish fed TAU5.0 % were significantly lower than those of fish fed TAU0 % for the first 7 d of exposure and the first 7 d of elimination. Our findings suggest a possible mechanism for the beneficial role played by taurine and that the inclusion of taurine in fish aquaculture feed may reduce cadmium contamination of fish intended for human consumption.

  17. Cadmium Exposure and Pancreatic Cancer in South Louisiana

    Science.gov (United States)

    Luckett, Brian G.; Su, L. Joseph; Rood, Jennifer C.; Fontham, Elizabeth T. H.

    2012-01-01

    Cadmium has been hypothesized to be a pancreatic carcinogen. We test the hypothesis that cadmium exposure is a risk factor for pancreatic cancer with a population-based case-control study sampled from a population with persistently high rates of pancreatic cancer (south Louisiana). We tested potential dietary and nondietary sources of cadmium for their association with urinary cadmium concentrations which reflect long-term exposure to cadmium due to the accumulation of cadmium in the kidney cortex. Increasing urinary cadmium concentrations were significantly associated with an increasing risk of pancreatic cancer (2nd quartile OR = 3.34, 3rd = 5.58, 4th = 7.70; test for trend P ≤ 0.0001). Potential sources of cadmium exposure, as documented in the scientific literature, found to be statistically significantly associated with increased risk of pancreatic cancer included working as a plumber, pipefitter or welder (OR = 5.88) and high consumption levels of red meat (4th quartile OR = 6.18) and grains (4th quartile OR = 3.38). Current cigarette smoking, at least 80 pack years of smoking, occupational exposure to cadmium and paints, working in a shipyard, and high consumption of grains were found to be statistically significantly associated with increased concentrations of urinary cadmium. This study provides epidemiologic evidence that cadmium is a potential human pancreatic carcinogen. PMID:23319964

  18. Effects of cadmium electrode properties on nickel-cadmium cell performance

    International Nuclear Information System (INIS)

    Zimmerman, A.H.

    1986-01-01

    Tests have been conducted on a number of nickel-cadmium cells that have exhibited a variety of performance problems, ranging from high voltages and pressures during overcharge to low capacity. The performance problems that have been specifically linked to the cadmium electrode are primarily related to two areas, poor sinter and the buildup of excessive pressure during overcharge. A number of specific nickel-cadmium cell and cadmium electrode characterists have been studied in this work to determine what the effects of poor sinter are, and to determine what factors are important in causing excessive pressures during overcharge in cells that otherwise appear normal. Several of the tests appear suitable for screening cells and electrodes for such problems

  19. Biogeochemistry of cadmium and its release to the environment.

    Science.gov (United States)

    Cullen, Jay T; Maldonado, Maria T

    2013-01-01

    Cadmium is at the end of the 4d-transition series, it is relatively mobile and acutely toxic to almost all forms of life. In this review we present a summary of information describing cadmium's physical and chemical properties, its distribution in crustal materials, and the processes, both natural and anthropogenic, that contribute to the metal's mobilization in the biosphere. The relatively high volatility of Cd metal, its large ionic radius, and its chemical speciation in aquatic systems makes Cd particularly susceptible to mobilization by anthropogenic and natural processes. The biogeochemical cycle of Cd is observed to be significantly altered by anthropogenic inputs, especially since the beginning of the industrial revolution drove increases in fossil fuel burning and non-ferrous metal extraction. Estimates of the flux of Cd to the atmosphere, its deposition and processing in soils and freshwater systems are presented. Finally, the basin scale distribution of dissolved Cd in the ocean, the ultimate receptacle of Cd, is interpreted in light of the chemical speciation and biogeochemical cycling of Cd in seawater. Paradoxically, Cd behaves as a nutrient in the ocean and its cycling and fate is intimately tied to uptake by photosynthetic microbes, their death, sinking and remineralization in the ocean interior. Proximate controls on the incorporation of Cd into biomass are discussed to explain the regional specificity of the relationship between dissolved Cd and the algal nutrient phosphate (PO[Formula: see text]) in oceanic surface waters and nutriclines. Understanding variability in the Cd/PO[Formula: see text] is of primary interest to paleoceanographers developing a proxy to probe the links between nutrient utilization in oceanic surface waters and atmospheric CO(2) levels. An ongoing international survey of trace elements and their isotopes in seawater will undoubtedly increase our understanding of the deposition, biogeochemical cycling and fate of this

  20. Influence of hydrophobization of fumed oxides on interactions with polar and nonpolar adsorbates

    Science.gov (United States)

    Gun'ko, V. M.; Pakhlov, E. M.; Goncharuk, O. V.; Andriyko, L. S.; Marynin, A. I.; Ukrainets, A. I.; Charmas, B.; Skubiszewska-Zięba, J.; Blitz, J. P.

    2017-11-01

    A variety of unmodified and modified fumed silica A-300 and silica/titania (ST20 and ST76 at 20 and 76 wt.% of titania, respectively) was prepared to analyze features of their interactions with polar and nonpolar adsorbates. The materials were studied using nitrogen adsorption-desorption, ethanol evaporation kinetics, infrared (IR) spectroscopy, thermogravimetry (TG), photon correlation spectroscopy, differential scanning calorimetry (DSC), DSC and TG thermoporometry, and quantum chemistry. Changes in surface structure of modified nanooxides with increasing hydrophobization degree (ΘMS) from 20% to 100% have a strong affect on the textural characteristics of the materials and adsorption-desorption of various adsorbates. Confined space effects enhanced due to the location of adsorbates in narrow voids between nanoparticles lead to freezing-melting point depression for bound polar and nonpolar adsorbates. The behavior of particles of modified nanooxides in aqueous and water/ethanol media is strongly altered due to enhanced aggregations with increasing value of ΘMS. All of these change are non-monotonic functions of ΘMS which affects (i) rearrangement of nanoparticles, (ii) interactions with polar and nonpolar adsorbates, (iii) location of adsorbates in voids of different sizes, (iv) the clustering of adsorbates and formation of nearly bulk structures.

  1. Number size distribution of fine and ultrafine fume particles from various welding processes.

    Science.gov (United States)

    Brand, Peter; Lenz, Klaus; Reisgen, Uwe; Kraus, Thomas

    2013-04-01

    Studies in the field of environmental epidemiology indicate that for the adverse effect of inhaled particles not only particle mass is crucial but also particle size is. Ultrafine particles with diameters below 100 nm are of special interest since these particles have high surface area to mass ratio and have properties which differ from those of larger particles. In this paper, particle size distributions of various welding and joining techniques were measured close to the welding process using a fast mobility particle sizer (FMPS). It turned out that welding processes with high mass emission rates (manual metal arc welding, metal active gas welding, metal inert gas welding, metal inert gas soldering, and laser welding) show mainly agglomerated particles with diameters above 100 nm and only few particles in the size range below 50 nm (10 to 15%). Welding processes with low mass emission rates (tungsten inert gas welding and resistance spot welding) emit predominantly ultrafine particles with diameters well below 100 nm. This finding can be explained by considerably faster agglomeration processes in welding processes with high mass emission rates. Although mass emission is low for tungsten inert gas welding and resistance spot welding, due to the low particle size of the fume, these processes cannot be labeled as toxicologically irrelevant and should be further investigated.

  2. Mechanism of alkalinity lowering and chemical equilibrium model of high fly ash silica fume cement

    International Nuclear Information System (INIS)

    Hoshino, Seiichi; Honda, Akira; Negishi, Kumi

    2014-01-01

    The mechanism of alkalinity lowering of a High Fly ash Silica fume Cement (HFSC) under liquid/solid ratio conditions where the pH is largely controlled by the soluble alkali components (Region I) has been studied. This mechanism was incorporated in the chemical equilibrium model of HFSC. As a result, it is suggested that the dissolution and precipitation behavior of SO 4 2- partially contributes to alkalinity lowering of HFSC in Region I. A chemical equilibrium model of HFSC incorporating alkali (Na, K) adsorption, which was presumed as another contributing factor of the alkalinity lowering effect, was also developed, and an HFSC immersion experiment was analyzed using the model. The results of the developed model showed good agreement with the experiment results. From the above results, it was concluded that the alkalinity lowering of HFSC in Region I was attributed to both the dissolution and precipitation behavior of SO 4 2- and alkali adsorption, in addition to the absence of Ca(OH) 2 . A chemical equilibrium model of HFSC incorporating alkali and SO 4 2- adsorption was also proposed. (author)

  3. Fume emissions from a low-cost 3-D printer with various filaments.

    Science.gov (United States)

    Floyd, Evan L; Wang, Jun; Regens, James L

    2017-07-01

    3-D printing is an additive manufacturing process involving the injection of melted thermoplastic polymers, which are then laid down in layers to achieve a pre-designed shape. The heated deposition process raises concerns of potential aerosol and volatile organic compounds (VOC) emission and exposure. The decreasing cost of desktop 3-D printers has made the use of 3-D printers more acceptable in non-industrial workplaces lacking sufficient ventilation. Meanwhile, little is known about the characteristics of 3-D printing fume emission. The objective of this study was to characterize aerosols and VOC emissions generated from various filaments used with a low-cost 3-D printer in an environmental testing chamber. A pre-designed object was printed in 1.25 hours using eight types of filaments. A scanning mobility particle sizer and an aerodynamic particle sizer were employed to measure the particle size distribution in sub-half-micron fraction (printers due to high respirablity, especially if used in settings without proper guidance and engineering control.

  4. Reduction of cooking oil fume exposure following an engineering intervention in Chinese restaurants.

    Science.gov (United States)

    Pan, Chih-Hong; Shih, Tung-Sheng; Chen, Chiou-Jong; Hsu, Jin-Huei; Wang, Shun-Chih; Huang, Chien-Ping; Kuo, Ching-Tang; Wu, Kuen-Yuh; Hu, Howard; Chan, Chang-Chuan

    2011-01-01

    A new engineering intervention measure, an embracing air curtain device (EACD), was used to increase the capture efficiency of cooker hoods and reduce cooking oil fume (COF) exposure in Chinese restaurants. An EACD was installed in six Chinese restaurants where the cooks complained of COF exposure. Before- and after-installation measurements were taken to compare changes in particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) in kitchen air, and changes in levels of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). The association between PM and PAHs in air and 8-OHdG and MDA in urine was evaluated by linear mixed-effects regression analysis. Results showed that geometric mean kitchen air levels of PM(10), PM(2.5), PM(1.0) and total particulate PAHs were significantly reduced after the EACDs were introduced. Urinary levels of 8-OHdG and MDA in cooks were also significantly lower after EACD instalment. PM(2.5), PM(1.0) and benzo(a)pyrene (BaP) levels were positively associated with urinary 8-OHdG levels after adjusting for key personal covariates. Urinary MDA levels in cooks were also positively associated with BaP levels after adjusting for key personal covariates. This study demonstrates that the EACD is effective for reducing COF and oxidative stress levels in cooks working in Chinese kitchens.

  5. Effects of cooking method, cooking oil, and food type on aldehyde emissions in cooking oil fumes.

    Science.gov (United States)

    Peng, Chiung-Yu; Lan, Cheng-Hang; Lin, Pei-Chen; Kuo, Yi-Chun

    2017-02-15

    Cooking oil fumes (COFs) contain a mixture of chemicals. Of all chemicals, aldehydes draw a great attention since several of them are considered carcinogenic and formation of long-chain aldehydes is related to fatty acids in cooking oils. The objectives of this research were to compare aldehyde compositions and concentrations in COFs produced by different cooking oils, cooking methods, and food types and to suggest better cooking practices. This study compared aldehydes in COFs produced using four cooking oils (palm oil, rapeseed oil, sunflower oil, and soybean oil), three cooking methods (stir frying, pan frying, and deep frying), and two foods (potato and pork loin) in a typical kitchen. Results showed the highest total aldehyde emissions in cooking methods were produced by deep frying, followed by pan frying then by stir frying. Sunflower oil had the highest emissions of total aldehydes, regardless of cooking method and food type whereas rapeseed oil and palm oil had relatively lower emissions. This study suggests that using gentle cooking methods (e.g., stir frying) and using oils low in unsaturated fatty acids (e.g., palm oil or rapeseed oil) can reduce the production of aldehydes in COFs, especially long-chain aldehydes such as hexanal and t,t-2,4-DDE. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Cadmium impact, accumulation and detection in poplar callus cells.

    Science.gov (United States)

    Kollárová, Karin; Vatehová, Zuzana; Kučerová, Danica; Lišková, Desana

    2017-06-01

    Effect of cadmium cations and their interaction with silicon cations was determined in poplar calli and expressed as changes in callus growth, cell viability and cadmium cation accumulation. Cell viability throughout culture versus cadmium cation accumulation in cells is discussed. At the same time, the study sought appropriate methods for cadmium cation detection in callus cells and also in experiments with low plant material (e.g. protoplasts). Cadmium cations were determined by atomic absorption spectroscopy and using fluorescence microscopy with a specific cadmium cation fluorescent dye. The detection of cadmium cations in callus cells by the latter method appears suitable because the callus cells are surrounded by primary cell walls without auto-fluorescence and these values fit well with atomic absorption spectroscopy quantification. However, the visualisation method has some limits discussed below.

  7. Polarization curves of solutions of high cadmium concentration

    International Nuclear Information System (INIS)

    Zosimovich, D.P.

    1979-01-01

    At electrochemical cadmium deposition on solid cathode of highly purified cadmium (out of solutions, containing 1.07m, 0.445; 0.312; 0.223; 0.107 mol/l of cadmium, 1 mol/l of sulfuric acid and 0.38 mol/l of zinc) it has been detected, that, cadmium deposition from these solutions agrees with the dependence epsilon - lg/isub(d)-i and for all cadmium concentrations investigated presents a straight line. It has been found that dependence of limiting current on cadmium concentration is a straight line; the mean value of the angle coefficient is 0.026; the mean value of semiwave potential constitutes 0.474+-6 mV as to hydrogen scale; the mean coefficient of cadmium diffusion equals to 2.37x10 -5 cm 2 /s -1

  8. Effects of Different Dietary Cadmium Levels on Growth and Tissue Cadmium Content in Juvenile Parrotfish,

    Directory of Open Access Journals (Sweden)

    Okorie E. Okorie

    2014-01-01

    Full Text Available This feeding trial was carried out to evaluate the effects of different dietary cadmium levels on growth and tissue cadmium content in juvenile parrotfish, Oplegnathus fasciatus, using cadmium chloride (CdCl2 as the cadmium source. Fifteen fish averaging 5.5±0.06 g (mean±SD were randomly distributed into each of twenty one rectangular fiber tanks of 30 L capacity. Each tank was then randomly assigned to one of three replicates of seven diets containing 0.30 (C0, 21.0 (C21, 40.7 (C41, 83.5 (C83, 162 (C162, 1,387 (C1,387 and 2,743 (C2,743 mg cadmium/kg diet. At the end of sixteen weeks of feeding trial, weight gain (WG, specific growth rate (SGR and feed efficiency (FE of fish fed C21 were significantly higher than those of fish fed C83, C162, C1,387 and C2,743 (p<0.05. Weight gain, SGR and FE of fish fed C0, C21 and C41 were significantly higher than those of fish fed C162, C1,387 and C2,743. Protein efficiency ratio of fish fed C0, C21 and C41 were significantly higher than those of fish fed C1,387 and C2,743. Average survival of fish fed C0, C21, C41 and C162 were significantly higher than that of fish fed C2,743. Tissue cadmium concentrations increased with cadmium content of diets. Cadmium accumulated the most in liver, followed by gill and then muscle. Muscle, gill and liver cadmium concentrations of fish fed C0, C21, C41 and C83 were significantly lower than those of fish fed C162, C1,387 and C2,743. Based on the ANOVA results of growth performance and tissue cadmium concentrations the safe dietary cadmium level could be lower than 40.7 mg Cd/kg diet while the toxic level could be higher than 162 mg Cd/kg diet.

  9. Cadmium Removal from Water and Soil by a Cadmium-Resistant Rhizobacterium and Its Effect on Plant Root Elongation

    OpenAIRE

    Chirawee Sangthong; Siranan Duangboobpha; Benjaphorn Prapagdee

    2015-01-01

    A cadmium resistant rhizobacterium, Pseudomonas sp. PM2, was isolated from plant roots. It is highly resistant to cadmium toxicity. The minimum inhibitory concentrations of cadmium for Pseudomonas sp. PM2 is 2100 mg/L. Pseudomonas sp. PM2 produced high levels of siderophore and rhamnolipid biosurfactant in 74.88 µM of deferoxamine mesylate equivalents and 329.54 mg/L, respectively. It was able to remove cadmium ion in an aqueous solution by 69.84% at the initial cadmium ion concentration of 2...

  10. Cadmium in Salix. A study to show the capacity of Salix to remove cadmium from farmland

    International Nuclear Information System (INIS)

    Oestman, G.

    1994-01-01

    The aim of this report has been to show the ability of Salix to take up cadmium and how the uptake varies between different types of soil. The information that the results are based on has been obtained from analyses of soil and Salix. The samples were taken at five sites in the district around Lake Maelaren. Two or three stands were taken at each place. The factors studied were the pH, the organic matter content, and the concentration of cadmium in the soil. Salix has a good ability, relative to other crops, to remove cadmium from arable land. The cadmium uptake is 35 times higher with Salix than with straw or energy grass. Salix uptake of cadmium varies between 3 and 14% of the cadmium content in the soil that is accessible to plants. The present annual increase of cadmium in arable land is 1 g/ha, whereas the removal in a Salix plantation is 21 g Cd/ha, yr at an annual growth of 10 tonnes DM. If the Cd uptake is the same each year, then a total of 420 g Cd/ha is removed when Salix is grown over a 20-year period. This is a very large part of the topsoil's total cadmium content, which is 550 g/ha on average in Sweden. The investigation reveals no clear relationship between the Cd concentration in Salix and the concentration of Cd in the soil, the organic matter content or the pH. 22 refs, 4 figs, 2 tabs

  11. Impact of iron status on cadmium uptake in suckling piglets

    International Nuclear Information System (INIS)

    Ohrvik, Helena; Oskarsson, Agneta; Lundh, Thomas; Skerfving, Staffan; Tallkvist, Jonas

    2007-01-01

    Low iron status is known to increase the uptake of dietary cadmium in both adolescents and adults and there are indications that cadmium is absorbed from the intestine by the two major iron transporters divalent metal transporter 1 (DMT1) and ferroportin 1 (FPN1). In addition, it has been suggested that duodenal metallothionein (MT) may limit the transport of cadmium across the intestinal epithelium. The present investigation was undertaken to examine whether iron status influences cadmium absorption in newborns by applying a model of suckling piglets and the possible roles of duodenal DMT1, FPN1 and MT. An oral cadmium dose (20 μg/kg body weight) was given daily for 6 consecutive days on postnatal days (PNDs) 10-15 to iron-deficient or iron-supplemented piglets. The cadmium dose was chosen to keep the cadmium level at a realistically low but still detectable level, and without inducing any adverse health effects in the piglets. As indicators of cadmium uptake, cadmium levels in blood and kidneys were measured on PND 16 by inductively coupled plasma-mass spectrometry (ICP-MS). Cadmium levels in blood were statistically significantly correlated with cadmium levels in kidneys. The cadmium uptake was not higher in iron-deficient suckling piglets; rather, we detected a higher cadmium uptake in the iron-supplemented ones. The expression and localisation of DMT1, FPN1 and MT were not affected by iron status and could therefore not explain the findings. Our results suggest that there are developmental differences in the handling of both iron and cadmium in newborns as compared to adults

  12. Environmental factors and uptake of cadmium among brazers using cadmium-containing hard solders.

    Science.gov (United States)

    Lundberg, I; Sjögren, B; Hallne, U; Hedström, L; Holgersson, M

    1984-06-01

    The influence of different work factors on the uptake of cadmium has been studied in 102 brazers working at least 10% of their work day with cadmium-containing hard solders. The blood concentrations of cadmium varied between less than 1 and 113 micrograms/L (less than 9 and 1010 nmol/L). Blood cadmium concentrations were below 10 micrograms/L (89 nmol/L) in 71 brazers and 31 brazers had levels equal to or above that value. The importance of some environmental factors on the blood-level of cadmium was studied with discrimination analysis. The length of the splice was found to be almost the sole determining factor for the cadmium concentration in blood. All brazers working with splices shorter than 2 cm had blood concentrations below 10 micrograms/L, while 87% of the brazers working with splices longer than 10 cm had blood concentrations equal to or above 10 micrograms/L. Other factors like age, sex, exposure time, smoking habit and brazing method were devoid of any measurable importance.

  13. Remediation of cadmium by Indian mustard (Brassica juncea L. from cadmium contaminated soil: a phytoextraction study

    Directory of Open Access Journals (Sweden)

    Rajeev Kumar Bhadkariya

    2014-05-01

    Full Text Available Cadmium is a toxic metal for living organisms and an environmental contaminant. Soils in many parts of the world are slightly too moderately contaminated by Cd due to long term use and disposal of Cd-contaminated wastes. Cost effective technologies are needed to remove cadmium from the contaminated sites. Soil phytoextraction is engineering based, low cost and socially accepted developing technology that uses plants to clean up contaminants in soils. This technology can be adopted as a remediation of cadmium from Cd-contaminated soils with the help of Brassica juncea plant. The objective of this work was to evaluate the cadmium (Cd accumulate and the tolerance of Brassica juncea. The Cd accumulates in all parts of plants (roots, stems and leaves. It was found that accumulating efficiency increased with the increase in the concentration of applied cadmium metal solution. Maximum accumulation of cadmium was found in roots than stem and leaves. Phytoextraction coefficient and translocation factor were highest to show the validity of the Brassica juncea species for hyperaccumulation of the Cd metal. These results suggested that Brassica juncea has a high ability to tolerate and accumulate Cd, so it might be a promising plant to be used for phytoextraction of Cd contaminated soil. DOI: http://dx.doi.org/10.3126/ije.v3i2.10533 International Journal of the Environment Vol.3(2 2014: 229-237

  14. Rising environmental cadmium levels in developing countries ...

    African Journals Online (AJOL)

    olayemitoyin

    these products. Satarug et al. ( 2003) had indeed predicted that given the current rate of release of cadmium in to the environment, Cd content in the ...... Armour, M.A. et al. (2005) Meeting report: Threat human health and environmental sustainability in the pacific basin. Environ Health. Perspect. 115: 1170-1174. Arthur, J.R. ...

  15. Combustion synthesis of cadmium sulphide nanomaterials

    Indian Academy of Sciences (India)

    Anion-doped cadmium sulphide nanomaterials have been synthesized by using combustionmethod at normal atmospheric conditions. Oxidant/fuel ratios have been optimized in order to obtain CdS with best characteristics. Formation of CdS and size of crystallite were identified by X-ray diffraction and confirmed by ...

  16. Cadmium versus phosphate in the world ocean

    NARCIS (Netherlands)

    Baar, Hein J.W. de; Saager, Paul M.; Nolting, Rob F.; Meer, Jaap van der

    1994-01-01

    Cadmium (Cd) is one of the best studied trace metals in seawater and at individual stations exhibits a more or less linear relation with phosphate. The compilation of all data from all oceans taken from over 30 different published sources into one global dataset yields only a broad scatterplot of Cd

  17. Subcellular localization of cadmium in hyperaccumulator Populus ...

    African Journals Online (AJOL)

    In this study, subcellular localization of cadmium in hyperaccumulator grey poplar (Populus × canescens) was investigated by the transmission electron microscopy (TEM) method. Young Populus × canescens were grown and hydroponic experiments were conducted under four Cd2+ concentrations (10, 30, 50, and 70 μM) ...

  18. Enhanced Electrokinetic Remediation of Cadmium Contaminated Soil

    African Journals Online (AJOL)

    In an attempt to remediate contaminated soil, a new technique of purging cadmium from soil is examined by enhanced electrokinetic method. It involves the passage of low level direct current between two electrodes in the soil to remove contaminant. An apparatus consisting of four principal parts; soil cell, electrode ...

  19. Characterization of nanocrystalline cadmium telluride thin films ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Structural, electrical and optical characteristics of CdTe thin films prepared by a chemical deposi- tion method, successive ionic layer adsorption and reaction (SILAR), are described. For deposition of CdTe thin films, cadmium acetate was used as cationic and sodium tellurite as anionic precursor in aqueous me-.

  20. Cadmium variability in leaves of a

    NARCIS (Netherlands)

    Luyssaert, S.; Meirvenne, M. Van; Lust, N

    2001-01-01

    Abstract: Plant analysis is a valuable tool to evaluate the pollution level. However, leaf sampling is complicated because of the high variability within the crown. To investigate the variability of cadmium (Cd) in the leaves of a tree, we sampled one Salix fragilis L. at 292 locations, each with a

  1. Rise time spectroscopy in cadmium telluride detectors

    International Nuclear Information System (INIS)

    Scharager, Claude; Siffert, Paul; Carnet, Bernard; Le Meur, Roger.

    1980-11-01

    By a simultaneous analysis of rise time and pulse amplitude distributions of the signals issued from various cadmium telluride detectors, it is possible to obtain informations about surface and bulk trapping, field distribution within the detectors, as well as charge collection and transport properties. These investigations have been performed on both pure and chlorine doped and materials for various surfaces preparation conditions [fr

  2. REMOVAL OF CADMIUM FROM AQUEOUS SOLUTION USING ...

    African Journals Online (AJOL)

    All synthesized products were thermally stable up to 300 oC and were highly insoluble in most mineral acids except hot perchloric acid. The sorption of cadmium ion from 0.1 M HNO3 solutions on manganese hexacyanoferrates (II) and (III) was investigated. Both sorption kinetics and isotherms were studied. The sorption ...

  3. Rising environmental cadmium levels in developing countries ...

    African Journals Online (AJOL)

    Summary: Cadmium (Cd) is a ubiquitous environmental pollutant of increasing worldwide concern. It is thought to be of greater concern to rapidly industrializing developing countries because of the increasing pace of industrial activities in these countries with increasing consumption and release into the environment.

  4. doped cadmium potassium phosphate hexahydrate: A substitutional ...

    Indian Academy of Sciences (India)

    Single crystal EPR studies of VO(II)-doped cadmium potassium phosphate hexahydrate (CPPH) have been carried out at room temperature. The angular variation spectra in the three orthogonal planes indicate that the paramagnetic impurity has entered the lattice only substitutionally in place of Cd(II). Spin Hamiltonian ...

  5. New process to discharge negative cadmium electrodes for Ni/Cd batteries

    International Nuclear Information System (INIS)

    Stiker, B.; Vignaud, R.

    1984-01-01

    The new process relates to the chemical oxidation (whether partial or total) of cadmium metal negative electrodes, as used in alkaline nickel-cadmium or silver-cadmium batteries. This process concerns all cadmium electrodes but more particularly the electrodeposited cadmium electrode developed by the company LES PILES WONDER and described in this publication

  6. Cadmium phytoextraction potential of different Alyssum species

    International Nuclear Information System (INIS)

    Barzanti, R.; Colzi, I.; Arnetoli, M.; Gallo, A.; Pignattelli, S.; Gabbrielli, R.; Gonnelli, C.

    2011-01-01

    Highlights: ► The possibility of using serpentine plants for phytoextraction of Cd was investigated. ► Variation in Cd tolerance, accumulation and translocation in three Alyssum plants with different phenotypes were found. ► Alyssum montanum showed higher Cd tolerance and accumulation than the Ni hyperaccumulator Alyssum bertolonii. ► As for the kinetic parameters of the Cd uptake system, A. montanum presented a low apparent K m value. ► The V max values were not significantly different among the plants. - Abstract: This work was planned for providing useful information about the possibility of using serpentine adapted plants for phytoextraction of cadmium, element scarcely represented in such metalliferous environment. To this aim, we investigated variation in cadmium tolerance, accumulation and translocation in three Alyssum plants with different phenotypes: Alyssum bertolonii, that is a serpentine endemic nickel hyperaccumulator, and two populations of Alyssum montanum, one adapted and one not adapted to serpentine soils. Plants were hydroponically cultivated in presence of increasing concentrations of CdSO 4 for two weeks. For the metal concentration used in the experiments, the three different Alyssum populations showed variation in cadmium tolerance, accumulation and content. The serpentine adapted population of A. montanum showed statistically higher cadmium tolerance and accumulation than A. bertolonii and the population of A. montanum not adapted to serpentine soil thus deserving to be investigated for phytoextraction purposes. Furthermore, as for the kinetic parameters of the cadmium uptake system, A. montanum serpentine population presented a low apparent K m value, suggesting a high affinity for this metal of its uptake system, whereas the V max values were not significantly different among the plants. Present data revealed metallicolous plants are also suitable for the phytoremediation of metals underrepresented in the environment of their

  7. Preparation and certification of two new bulk welding fume reference materials for use in laboratories undertaking analysis of occupational hygiene samples.

    Science.gov (United States)

    Butler, Owen; Musgrove, Darren; Stacey, Peter

    2014-01-01

    Workers can be exposed to fume, arising from welding activities, which contain toxic metals and metalloids. Occupational hygienists need to assess and ultimately minimize such exposure risks. The monitoring of the concentration of particles in workplace air is one assessment approach whereby fume, from representative welding activities, is sampled onto a filter and returned to a laboratory for analysis. Inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry are generally employed as instrumental techniques of choice for the analysis of such filter samples. An inherent difficulty, however, with inductively coupled plasma-based analytical techniques is that they typically require a sample to be presented for analysis in the form of a solution. The efficiency of the required dissolution step relies heavily upon the skill and experience of the analyst involved. A useful tool in assessing the efficacy of this dissolution step would be the availability and subsequent analysis of welding fume reference materials with stated elemental concentrations and matrices that match as closely as possible the matrix composition of welding fume samples submitted to laboratories for analysis. This article describes work undertaken at the Health and Safety Laboratory to prepare and certify two new bulk welding fume reference materials that can be routinely used by analysts to assess the performance of the digestion procedures they employ in their laboratories.

  8. Evaluation of the Pulmonary Toxicity of a Fume Generated from a Nickel-, Copper-Based Electrode to be Used as a Substitute in Stainless Steel Welding

    Science.gov (United States)

    Antonini, James M; Badding, Melissa A; Meighan, Terence G; Keane, Michael; Leonard, Stephen S; Roberts, Jenny R

    2014-01-01

    Epidemiology has indicated a possible increase in lung cancer among stainless steel welders. Chromium (Cr) is a primary component of stainless steel welding fume. There is an initiative to develop alternative welding consumables [nickel (Ni)- and copper (Cu)-based alloys] that do not contain Cr. No study has been performed to evaluate the toxicity of fumes generated from Ni- and Cu-based consumables. Dose–response and time-course effects on lung toxicity of a Ni- and Cu-based welding fume (Ni–Cu WF) were examined using an in vivo and in vitro bioassay, and compared with two other well-characterized welding fumes. Even though only trace amounts of Cr were present, a persistent increase in lung injury and inflammation was observed for the Ni–Cu WF compared to the other fumes. The difference in response appears to be due to a direct cytotoxic effect by the Ni–Cu WF sample on lung macrophages as opposed to an elevated production of reactive oxygen species (ROS). PMID:25392698

  9. Size-separated particle fractions of stainless steel welding fume particles - A multi-analytical characterization focusing on surface oxide speciation and release of hexavalent chromium.

    Science.gov (United States)

    Mei, N; Belleville, L; Cha, Y; Olofsson, U; Odnevall Wallinder, I; Persson, K-A; Hedberg, Y S

    2018-01-15

    Welding fume of stainless steels is potentially health hazardous. The aim of this study was to investigate the manganese (Mn) and chromium (Cr) speciation of welding fume particles and their extent of metal release relevant for an inhalation scenario, as a function of particle size, welding method (manual metal arc welding, metal arc welding using an active shielding gas), different electrodes (solid wires and flux-cored wires) and shielding gases, and base alloy (austenitic AISI 304L and duplex stainless steel LDX2101). Metal release investigations were performed in phosphate buffered saline (PBS), pH 7.3, 37°, 24h. The particles were characterized by means of microscopic, spectroscopic, and electroanalytical methods. Cr was predominantly released from particles of the welding fume when exposed in PBS [3-96% of the total amount of Cr, of which up to 70% as Cr(VI)], followed by Mn, nickel, and iron. Duplex stainless steel welded with a flux-cored wire generated a welding fume that released most Cr(VI). Nano-sized particles released a significantly higher amount of nickel compared with micron-sized particle fractions. The welding fume did not contain any solitary known chromate compounds, but multi-elemental highly oxidized oxide(s) (iron, Cr, and Mn, possibly bismuth and silicon). Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Modelling of cadmium fluxes on energy crop land

    International Nuclear Information System (INIS)

    Palm, V.

    1992-04-01

    The flux of cadmium on energy crop land is investigated. Three mechanisms are accounted for; Uptake by plant, transport with water, and sorption to soil. Sorption is described with Freundlich isotherms. The system is simulated mathematically in order to estimate the sensitivity and importance of different parameters on the cadmium flow and sorption. The water flux through the soil and the uptake by plants are simulated with a hydrological model, SOIL. The simulated time period is two years. The parameters describing root distribution and evaporation due to crop are taken from measurements on energy crop (Salix). The resulting water flux, water content in the soil profile and the water uptake into roots, for each day and soil compartment, are used in the cadmium sorption simulation. In the cadmium sorption simulation the flux and equilibrium chemistry of cadmium is calculated. It is shown that the amount of cadmium that accumulates in the plant, and the depth to which the applied cadmium reaches depends strongly on the constants in the sorption isotherm. With an application of 10 mg Cd/m 2 in the given range of Freundlich equations, the simulations gave a plant uptake of between 0 and 30 % of the applied cadmium in two years. At higher concentrations, where cadmium sorption can be described by nonlinear isotherms, more cadmium is present in soil water and is generally more bioavailable. 25 refs

  11. Cadmium-induced fetal toxicity in the rat

    International Nuclear Information System (INIS)

    Levin, A.A.

    1980-01-01

    Cadmium, a heavy metal environment contaminant, induces fetal death and placental necrosis in the Wistar rat. This study investigated fetal, maternal, and placental responses to cadmium intoxication. Subcutaneous injection of CdCl 2 to dams on day 18 of pregnancy produced a high incidence of fetal death (75%) and placental necrosis. Death in the fetus was produced despite limited fetal accumulations of cadmium. Distribution studies using 109 Cd-labeled CdCl 2 demonstrated that less than 0.1% of the injected dose was associated with the fetus. To determine if fetuses were sensitive to these low levels of cadmium, direct injections of CdCl 2 into fetuses were performed in utero. Direct injections produced fetal accumulations 8-fold greater than those following maternal injections. The 8-fold greater fetal accumulations following direct injection were associated with only a 12% fetal mortality compared to the 75% mortality following maternal injections. The data indicated that the fetal toxicity of cadmium following maternal injections was not the result of direct effects of cadmium on the fetus. In conclusion, cadmium-induced fetal death was not the result of direct effects of cadmium on the fetus but may have been induced by placental cellular injury resulting from high accumulations of cadmium in the placenta. A vascular response to placental injury, leading to decreased utero-placental bood flow and cadmium-induced alterations in trophoblastic function, resulted in fetal death

  12. Influence of silica fume on mechanical and physical properties of recycled aggregate concrete

    Directory of Open Access Journals (Sweden)

    Özgür Çakır

    2015-08-01

    Full Text Available Several studies related to sustainable concrete construction have encouraged development of composite binders, involving Portland cement, industrial by-products, and concrete mixes with partial replacement of natural aggregate with recycled aggregate. In this paper, the effects of incorporating silica fume (SF in the concrete mix design to improve the quality of recycled aggregates in concrete are presented. Portland cement was replaced with SF at 0%, 5% and 10%. Specimens were manufactured by replacing natural aggregates with recycled aggregates. Two size fractions (4/12 mm and 8/22 mm as recycled aggregates were used and four series of concrete mixtures were produced. In all concrete mixtures, a constant water/binder ratio at 0.50 was used and concrete mixtures with a target initial slump of S4 class (16–21 cm were prepared. Concrete properties were evaluated by means of compressive strength, tensile splitting strength, water absorption and ultrasonic pulse velocity and it was found that, using 10% SF as a cement replacement for recycled aggregate concretes enhanced the mechanical and physical properties of concrete. At all the test ages the tensile splitting strength gain of the natural aggregate concrete mixture (NA with and without SF was higher than that of the recycled concrete mixtures. Continuous and significant improvement in the tensile splitting strength of recycled aggregate concretes incorporating SF was observed. Similar to compressive strength test results, concrete incorporating 10% SF and containing 4/12 mm fraction recycled aggregates showed better performance among recycled aggregate concretes.

  13. Electrospun hydrophilic fumed silica/polyacrylonitrile nanofiber-based composite electrolyte membranes

    International Nuclear Information System (INIS)

    Jung, Hong-Ryun; Ju, Dong-Hyuk; Lee, Wan-Jin; Zhang, Xiangwu; Kotek, Richard

    2009-01-01

    Hydrophilic fumed silica (SiO 2 )/polyacrylonitrile (PAN) composite electrolyte membranes were prepared by electrospinning composite solutions of SiO 2 and PAN in N,N-dimethylformamide (DMF). Among electrospinning solutions with various SiO 2 contents, the 12 wt% SiO 2 in PAN solution has highest zeta potential (-40.82 mV), and exhibits the best dispersibility of SiO 2 particles. The resultant 12 wt% SiO 2 /PAN nanofiber membrane has the smallest average fiber diameter, highest porosity, and largest specific surface area. In addition, this membrane has a three-dimensional network structure, which is fully interconnected with combined mesopores and macropores because of a good SiO 2 dispersion. Composite electrolyte membranes were prepared by soaking these porous nanofiber membranes in 1 M lithium hexafluorophosphate (LiPF 6 ) in ethylene carbonate (EC)/dimethyl carbonate (DMC) (1:1 vol%). It is found that 12 wt% SiO 2 /PAN electrolyte membrane has the highest conductivity (1.1 x 10 -2 S cm -1 ) due to the large liquid electrolyte uptake (about 490%). In addition, the electrochemical performance of composite electrolyte membranes is also improved after the introduction of SiO 2 . For initial cycle, 12 wt% SiO 2 /PAN composite electrolyte membrane delivers the discharge capacity of 139 mAh g -1 as 98% of theoretical value, and still retains a high value of 127 mAh g -1 as 89% at 150th cycle, which is significantly higher that of pure PAN nanofiber-based electrolyte membranes.

  14. The Far Ultraviolet M-dwarf Evolution Survey (FUMES): Overview and Initial Results

    Science.gov (United States)

    Pineda, J. Sebastian; France, Kevin; Youngblood, Allison

    2018-01-01

    M-dwarf stars are prime targets for exoplanet searches because of their close proximity and favorable properties for both planet detection and characterization, with current searches around these targets having already discovered several Earth-sized planets within their star’s habitable zones. However, the atmospheric characterization and potential habitability of these exoplanetary systems depends critically on the high-energy stellar radiation environment from X-rays to NUV. Strong radiation at these energies can lead to atmospheric mass loss and is a strong driver of photochemistry in planetary atmospheres. Recently, the MUSCLES Treasury Survey provided the first comprehensive assessment of the high-energy radiation field around old, planet hosting M-dwarfs. However, the habitability and potential for such exoplanetary atmospheres to develop life also depends on the evolution of the atmosphere and hence the evolution of the incident radiation field. The strong high-energy spectrum of young M-dwarfs can have devastating consequences for the potential habitability of a given system. We, thus, introduce the Far Ultraviolet M-dwarf Evolution Survey (FUMES), a new HST-STIS observing campaign targeting 10 early-mid M dwarfs with known rotation periods, including 6 targets with known ages, to assess the evolution of the FUV radiation, including Lyα, of M-dwarf stars with stellar rotation period. We present the initial results of our survey characterizing the FUV emission features of our targets and the implications of our measurements for the evolution of the entire high-energy radiation environment around M-dwarfs from youth to old age.

  15. Frankincense and myrrh essential oils and burn incense fume against micro-inhabitants of sacral ambients. Wisdom of the ancients?

    Science.gov (United States)

    Ljaljević Grbić, Milica; Unković, Nikola; Dimkić, Ivica; Janaćković, Peđa; Gavrilović, Milan; Stanojević, Olja; Stupar, Miloš; Vujisić, Ljubodrag; Jelikić, Aleksa; Stanković, Slaviša; Vukojević, Jelena

    2018-03-09

    Essential oils obtained from resins of Boswellia carteri Birdw. and Commiphora myrrha (Nees) Engl., commonly known as frankincense and true myrrh respectively, have been used extensively since 2800 BCE for the treatment of skin sores, wounds, teeth, inflammation, and urinary tract diseases in traditional medicine; for preparation of mummification balms and unguents; and also as incense and perfumes. Since ancient times, burning of frankincense and myrrh in places of worship for spiritual purposes and contemplation (a ubiquitous practice across various religions) had hygienic functions, to refine the smell and reduce contagion by purifying the indoor air. The general purpose of the study was to assess the in vitro antimicrobial potential of the liquid and vapour phases of B. carteri and C. myrrha essential oils and burn incense, as well as to test the effectiveness of their in situ application to cleanse microbially-contaminated air within the ambient of an investigated 17th-century church. The chemical composition of B. carteri and C. myrrha essential oils, obtained by hydrodistillation of frankincense and true myrrh oleo gum resins was determined using GC/MS, and antimicrobial properties of their liquid and vapour phases were assessed by the broth microdilution and microatmosphere diffusion methods. Chemical analysis of burn incense fume obtained using bottle gas washing with dichloromethane as a solvent was performed by GC/MS, while its antimicrobial activity was evaluated using a modified microatmosphere diffusion method to evaluate germination inhibition for fungi and CFU count reduction for bacteria. The in situ antimicrobial activity of B. carteri burn incense and essential oil vapour phase was assessed in the sealed nave and diaconicon of the church, respectively. The dominant compounds of B. carteri EO were α-pinene (38.41%) and myrcene (15.21%), while C. myrrha EO was characterized by high content of furanoeudesma-1,3-diene (17.65%), followed by curzerene

  16. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    Science.gov (United States)

    Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

    2014-01-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  17. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures.

    Science.gov (United States)

    Wang, Ning; Ingersoll, Christopher G; Dorman, Rebecca A; Brumbaugh, William G; Mebane, Christopher A; Kunz, James L; Hardesty, Doug K

    2014-10-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th-82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper. Published 2014 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

  18. Enhanced cadmium phytoremediation of Glycine max L. through bioaugmentation of cadmium-resistant bacteria assisted by biostimulation.

    Science.gov (United States)

    Rojjanateeranaj, Pongsarun; Sangthong, Chirawee; Prapagdee, Benjaphorn

    2017-10-01

    This study examined the potential of three strains of cadmium-resistant bacteria, including Micrococcus sp., Pseudomonas sp. and Arthrobacter sp., to promote root elongation of Glycine max L. seedlings, soil cadmium solubility and cadmium phytoremediation in G. max L. planted in soil highly polluted with cadmium with and without nutrient biostimulation. Micrococcus sp. promoted root length in G. max L. seedlings under toxic cadmium conditions. Soil inoculation with Arthrobacter sp. increased the bioavailable fraction of soil cadmium, particularly in soil amended with a C:N ratio of 20:1. Pot culture experiments observed that the highest plant growth was in Micrococcus sp.-inoculated plants with nutrient biostimulation. Cadmium accumulation in the roots, stems and leaves of G. max L. was significantly enhanced by Arthrobacter sp. with nutrient biostimulation. A combined use of G. max L. and Arthrobacter sp. with nutrient biostimulation accelerated cadmium phytoremediation. In addition, cadmium was retained in roots more than in stems and leaves and G. max L. had the lowest translocation factor at all growth stages, suggesting that G. max L. is a phytostabilizing plant. We concluded that biostimulation-assisted bioaugmentation is an important strategy for improving cadmium phytoremediation efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. [Polycyclic aromatic hydrocarbons and soluble organic fraction in fine particles from solid fraction of biodiesel exhaust fumes].

    Science.gov (United States)

    Szewczyńska, Małgorzata; Pośniak, Małgorzata

    2012-01-01

    This paper presents the results of investigations into the distribution of fine particles in the biodiesel exhaust fumes (bio-DEP), as well as into the content of polycyclic aromatic hydrocarbons (PAHs) and soluble organic fraction (SOF) in the study fractions. Samples of biodiesel B20 and B40 exhaust combustion fumes were generated at the model station composed of a diesel engine from Diesel TDI 2007 Volkswagen. Sioutas personal cascade impactor (SPCI) with Teflon filters and low-pressure impactor ELIPI (Dekati Low Pressure Impactor) were used for sampling diesel exhaust fine particles. The analysis of PAHs adsorbed on particulate fractions was performed by high performance liquid chromatography with fluorescence detection (HPLC/FL). For the determination of dry residue soluble organic fraction of biodiesel exhaust particles the gravimetric method was used. The combustion exhaust fumes of 100% ON contained mainly naphthalene, acenaphthalene, fluorene, phenanthrene, fluoranthene, pyrene, benzo(a)anthracene and chrysene, whilst the exhaust of B40-single PAHs of 4 and 5 rings, such as chrysene, benzo(k)fluoranthene, dibenzo (ah)anthracene and benzo(ghi)perylene. The total content of PAHs in diesel exhaust particles averaged 910 ng/m3 for 100% ON and 340 ng/m3 for B40. The concentrations of benzo(a)antarcene were at the levels of 310 ng/m3 (100% ON) and 90 ng/m3 (B40). The investigations indicated that a fraction < 025 microm represents the main component of diesel exhaust particles, regardless of the used fuel. Bioester B 100 commonly added to diesel fuel (ON) causes a reduction of the total particulates emission and thus reduces the amount of toxic substances adsorbed on their surface.

  20. Abrasion Properties of Steel Fiber Reinforced Silica Fume Concrete According to Los Angeles and Water Abrasion Tests

    Directory of Open Access Journals (Sweden)

    Tsan-Ching CHENG

    2014-12-01

    Full Text Available The current study mainly investigated the influence of different tests on the abrasion resistance of concrete mixed with steel fibers and silica fume. The abrasion resistance was assessed at 28, 56 and 91 days on concretes with water-binder ratios of 0.35 and 0.55 where in some mixes silica fume was substituted by 5 % of cement by weight. Steel fibers of 0.5 % and 1.0 % of concrete volume were also added into the test concrete by replacement of coarse and fine aggregates. The results showed that concrete with higher compressive strength in Los Angeles abrasion tests also had better abrasion resistance. The inclusion of steel fibers into test concrete with a water-binder ratio of 0.35 resulted in a significant increase in compressive strength. This concrete also displayed better abrasion resistance and splitting tensile strength than reference concrete; in the test sample with a water-binder ratio of 0.55, the added steel fibers was unable to effectively produce cementation with the concrete. The inclusion of silica fume improved the abrasion resistance of concretes. In water abrasion testing, the abrasion resistance of concrete containing steel fiber was worse than that of concrete without steel fibers. In the water abrasion testing, the surface of steel fiber reinforced concrete was eroded by water and steel balls, and the impact caused the steel fibers to separate from the concrete and led to higher wear loss. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6460