OPPT_Asbestos, Part I: Chrysotile_Supplemental Search

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2979

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OPPT REs

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Journal Article

Abstract  There is ongoing argument about the potency of chrysotile asbestos to cause malignant mesothelioma. Risk assessment for chrysotile is influenced by the alleged absence of mesotheliomas among workers at the Raybestos Manhattan friction products plant in Connecticut, a plant that essentially used only chrysotile asbestos. Regrettably, the statement that there is an absence of mesothelioma deaths in the Connecticut plant is false. In this paper, we report on our review of the work histories and pathological reports of five individuals from the Connecticut plant who were diagnosed with mesothelioma. We discuss the Connecticut plant in relation to the most recent epidemiological information for chrysotile. Calculation suggests that mesothelioma rates at this plant were similar to those observed among Quebec miners and the South Carolina textile plant. We urge everyone concerned with the risk assessment of chrysotile asbestos to make use of all available data.

Journal Article

Abstract  The chronic toxicity of vitreous fibers is substantially dependent on their biopersistence. Removal of fibers deposited in the respiratory tract is dependent on a combination of physiological clearance processes (like mechanical translocation) and physico-chemical processes like dissolution and leaching. This publication presents data of about 60 different fibers investigated in the biopersistence test which was standardized in the European Union. This test is based on in vivo investigation of biopersistence after intratracheal instillation in rats of a respirable fiber fraction, and it is a basis for the regulatory classification of vitreous fibers. Regression analysis is carried out employing the data of glass fiber compositions and the corresponding results of biopersistence tests (half-times). The study leads to a model that enables prediction of half-times for stone wool fibers as well as for glass wool fibers on the basis of their chemical composition. The aim of this paper was to investigate the stringency of the existing limits for the range of the chemical composition of glass and stone wools in view of the currently available data base. For regulatory purposes, however, this model is currently not sufficient to replace biopersistence tests completely.

Journal Article

Abstract  BIOSIS COPYRIGHT: BIOL ABS. With a grant from the Italian Ministry of the Environment, the National Institute of Health (Istituto Superiore de Sanita) promoted and coordinated some activities aimed at determining the extent and the intensity of contamination of waters used for human consumption by some chemical agents, and describing causes and modalities of contamination and human health implications. The chemical agents examined were herbicides, nitrates, trihalomethanes, asbestos, manganese and fluoride. In this paper a first nationwide picture of these problems is reported.

DOI
Journal Article

Abstract  Geopolymers are environmentally friendly substitutes for Portland cement; in many applications, geopolymers not only reduce greenhouse gas emissions but also are recyclable. The hardening mechanism of geopolymer polymerization differs from that of ordinary Portland cement. In the present research, two methods are used to evaluate the microstructure of this inorganic material. In the first method, complete polymerization was observed by means of scanning electron microscopy (SEM) to reveal the foundations of strength establishment. The SEM results show that the synthesized geopolymer maintained a layer structure of metakaolinite particulates. Therefore, it was thought that the geopolymeric reaction mainly occurred at the surface of microflakes of metakaolinite particulates. In order to further investigate the polymerization process of the material, two Raman spectrum frequency ranges-875 nm and 325 nm-were used in the study because of their capability to characterize the mineral/hydrated phases under a thick post-treatment layer. Also, in order to facilitate quality control of the production and explore the extreme compressive strengths of metakaolin cement, the polymerization mechanism and microstructures of the products were monitored step by step using Raman spectroscopy. The lessons learned in the research program can be used to advance the research methodology needed for further investigation of the strength enhancement of the geopolymer.

WoS
Journal Article

Abstract  Investigations were performed on tannery wastewater, previously coagulated with FeCl(3). An electrolyzer was equipped with two graphite cathodes and Ti/SnO(2)/PdO(2)/RuO(2) anode, divided by the diaphragm made of asbestos fibre. The current density was: cathodic 2.0 A/dm(2) and anodic 2.1 A/dm(2). After 55 min of the process the catholyte was transferred into the anodic space and the process was continued. After 55 min of electro-Fenton process, the COD was reduced by 52.0% (current efficiency of COD removal was 10.6%). Electrooxidation continued by the anodic process resulted in elimination of ammonia in 55 min and a total reduction of COD by 72.9%. The coupled process d could be considered a simulation of the combined process under flow conditions. The effect of this process was compared to that of a two-steps process: Fenton process followed by indirect anodic oxidation.

DOI
Journal Article

Abstract  The permanent deformation performance of asphalt concrete is strongly dependent on the rheological properties of the asphalt binder. It has been recognized that the asphalt's low shear viscosity (LSV) characterizes the mixture's rutting resistance. At the same time, the pavement temperature is one of the main factors that significantly affect the mixture performance. In this work the rutting performance of mixtures prepared with the same aggregate gradation and different binders [conventional (C), multigrade (M) and polymer modified (PM) asphalts] were evaluated by using wheel tracking tests (WTT) performed at 50, 60, 70 and 80A degrees C; in parallel, the LSV of asphalts were measured at the same temperatures. The relationship between the asphalt's LSV and rutting, to predict asphalt mixture performance, was discussed and a criterion to consider the effect of LSV is proposed.

Journal Article

Abstract  AIMS: To investigate the consequences of improvement in the workplace environment over six decades (1940-96) in asbestos miners and millers from a developing country (Brazil).

METHODS: A total of 3634 Brazilian workers with at least one year of exposure completed a respiratory symptoms questionnaire, chest radiography, and a spirometric evaluation. The study population was separated into three groups whose working conditions improved over time: group I (1940-66, n = 180), group II (1967-76, n = 1317), and group III (1977-96, n = 2137).

RESULTS: Respiratory symptoms were significantly related to spirometric abnormalities, smoking, and latency time. Breathlessness, in particular, was also associated with age, pleural abnormality and increased cumulative exposure to asbestos fibres. The odds ratios (OR) for parenchymal and/or non-malignant pleural disease were significantly lower in groups II and III compared to group I subjects (0.29 (0.12-0.69) and 0.19 (0.08-0.45), respectively), independent of age and smoking status. Similar results were found when groups were compared at equivalent latency times (groups I v II: 30-45 years; groups II v III: 20-25 years). Ageing, dyspnoea, past and current smoking, and radiographic abnormalities were associated with ventilatory impairment. Lower spirometric values were found in groups I and II compared to group III: lung function values were also lower in higher quartiles of latency and of cumulative exposure in these subjects.

CONCLUSIONS: Progressive improvement in occupational hygiene in a developing country is likely to reduce the risk of non-malignant consequences of dust inhalation in asbestos miners and millers.

Journal Article

Abstract  The Carotene and Retinol Efficacy Trial (CARET) was a double-blind, placebo-controlled trial of the daily administration of 25,000 IU vitamin A and 30 mg beta-carotene for the prevention of lung cancer. Of close to 18,500 participants, more than 4,000 were asbestos-exposed men recruited from shipyard and construction trades at five study centers in the United States. While the primary endpoint of the trial was the incidence of lung cancer, a number of questions about the natural history of asbestos-related disease will also be addressed. The mean age at entry into the trial was 57 years and the mean duration of follow-up on active intervention was 4 years. With the exception of 133 never-smoker pilot participants (3%), all subjects recruited were by intention current (38%) or ex-smokers (58%), with a mean cumulative smoking exposure at entry of 43 pack-years. Mean years from first asbestos exposure were 35, and mean duration of asbestos exposure in a high-risk trade was 19 years. The distribution of radiographic abnormalities was as follows: normal, 34%; parenchymal opacities (ILO profusion score > 1/0) alone, 18%; pleural thickening alone, 27%; both parenchymal opacities and pleural thickening, 21%. The CARET cohort, when compared to previously reported asbestos-exposed cohorts, is characterized by substantial asbestos exposure and high proportion of asbestos-related radiographic findings. The active intervention was halted in 1996, after a mean duration of 40 years. Passive follow-up of the cohort will continue until the year 2000.

Journal Article

Abstract  BACKGROUND: Most studies on asbestos-related diseases describe the associations between exposure and disease and the factors influencing that association. It is recognized that there is a long latency period between exposure and disease, but the health status of affected individuals after long-term non-exposure is uncertain.

OBJECTIVES: To describe the changes in pulmonary function tests (PFTs) and computed tomographic imaging of the thorax over a 15 year period after cessation of exposure to asbestos in a cohort of Israeli power plant workers.

METHODS: Israeli power plant workers whose PFTs and thoracic CT imaging between 1993 and 1998 revealed asbestos-related disease underwent a second clinical, functional and imaging evaluation up to 15 years later. The two sets of results were compared.

RESULTS: Of the original cohort of 59 males, 35 were still alive and 18 of them agreed to take part in the current study. The mean length of their exposure was 30 +/- 10.06 years (range 7-43 years). Comparison of the initial and follow-up examination findings revealed a significant increase in calcification of the pleural plaques (from 37% to 66%, P = 0.008) and a deterioration in PFT results (P= 0.04). Of the 24 men who died, malignant disease was the cause of death in 53%, mostly in sites other than the respiratory system.

CONCLUSIONS: PFTs declined and CT findings worsened in subjects who were formerly exposed to asbestos and had not been exposed to it for over a decade. Continued monitoring of individuals exposed to asbestos, even decades after the cessation of exposure, is recommended.

Journal Article

Abstract  The 1980 International Labour Office (ILO) classification of posteroanterior chest radiographs was used to obtain the scores for profusion of small opacities and pleural abnormalities of 172 men with confirmed or suspected disease of the lungs due to asbestos. After allowance had been made for age, stature, and smoking habit the quantitative score for area of diffuse pleural thickening seen in profile on both lateral chest walls contributed to reductions in inspiratory capacity, expiratory reserve volume, and forced expiratory flow rates. Occlusion of one or both costophrenic angles in the presence of diffuse thickening was associated with further reduction in inspiratory capacity. Profusion of small opacities was associated with a reduction in transfer factor. Diffuse pleural thickening and occlusion of costophrenic angles were associated with relatively low values for the forced expiratory flow rates (MEF50FVC) and FEV1/FVC, whereas small opacities were associated with relatively high values. Thus overall increased, normal, or reduced values of MEF50FVC and FEV1/FVC might occur, depending on the distribution of the radiographic abnormalities. The findings contribute to the validation of the ILO pleural scores; those for diffuse pleural thickening and occlusion of costophrenic angles should be used jointly with the scores for profusion of parenchymal small opacities in interpreting the lung function of persons exposed to asbestos.

Journal Article

Abstract  Forty-five men with asbestos-related pleural plaques detected at a health screening centre were investigated with measurement of lung volumes, airways resistance, ventilatory capacity, transfer factor, gas distribution, closing volume and static recoil pressures of the lung. The men were subjectively healthy, had confirmed exposure to asbestos and had normal chest radiograms apart from the presence of pleural plaques. Most of the men had been exposed to small or moderate amounts of asbestos with a mean duration of 39 years since first exposure. Sixty-seven per cent of the men were smokers or ex-smokers. The lung function was evaluated using regression formulas which included smoking variables. The results clearly demonstrate the presence of lung parenchymal involvement with increased stiffness of the lungs and decreased lung volumes. The change in elastic recoil pressure of the lungs, in total lung capacity and residual volume show significant correlation with measures of asbestos exposure and extent of pleural changes. No synergistic effects between tobacco smoking and asbestos exposure on lung function could be demonstrated. Measurements of the static elastic lung recoil (Pst(max) and Cst/TLC) and total lung capacity were the most sensitive tests for separating the pleural plaque carriers from the controls.

Journal Article

Abstract  OBJECTIVES: A cross sectional study was undertaken to assess lung health among plumbers and pipefitters. Respiratory symptoms, lung function, and radiographic changes among 99 actively employed plumbers and pipefitters with > or = 20 years of union membership were compared with 100 telephone workers.

METHODS: A respiratory symptom questionnaire was administered, including smoking and occupational histories. Spirometry was conducted according to standard criteria. Posteroanterior chest radiographs were evaluated by two experienced chest physicians, with a third arbitrating disagreed films. Members of the union were categorised as pipefitters (n = 57), plumbers (n = 16), or welders (n = 26), based on longest service, and compared with the telephone workers and internally (between groups). Lung health was also compared with employment in several work sectors common to Alberta for time, and for time weighted by exposure to dust and fumes.

RESULTS: Compared with the telephone workers, plumbers and pipefitters had more cough and phlegm, lower forced vital capacity, and more radiographic changes (20% with any change), including circumscribed (10%) and diffuse pleural thickening (9%). None of the plumbers and pipefitters had small radiographic opacities. Among the three subgroups of workers, plumbers had the highest prevalence of radiographic changes. Both plumbers and pipefitters showed higher odds ratios for cough and phlegm than the welders. No differences between groups were found for lung function. Indicators of lung health were not related to work in any sector.

CONCLUSIONS: Plumbers and pipefitters had increased prevalence of symptoms suggestive of an irritant effect with no evidence of bronchial responsiveness. The chest radiographs showed evidence of asbestos exposure, especially in the plumbers, but at lower levels than previously reported. Health screening programmes for these workers should be considered, although the logistical problems associated with screening in this group would be considerable.

Journal Article

Abstract  From the County of Uppsala, Sweden, more than 1600 persons with pleural plaques and/or asbestos-related pleural thickening have been seen at the Uppsala University Hospital during a period of about 15 years. During the observation time, 40 patients developed lesions mainly affecting the upper lobes of the lung. They were all men, 41 to 78-years-old, and all had been occupationally exposed to asbestos. The mean latency time from the first exposure was 34 years. The mean width of the apical pleural thickening was 21 mm. In 21 patients the lesions were on the right side, in 15 they were bilateral, and in only four patients was the left side alone affected. Biopsies from the pleura were available in twelve patients and from the lung parenchyma in eight. The biopsies of the lungs all showed varying degrees of asbestosis and of the pleura nonspecific pleuritis. The lesions tended to progress and in all cases except one they were part of a diffuse pleural and parenchymal fibrosis involving the rest of the lung. Consequently, the pulmonary function was impaired, with the vital capacity reduced to an average of 62% and total lung capacity to 68% of the predicted value. In many patients there was contraction of the upper lobe and deviation of the trachea towards the same side. Upper lobe changes are a relatively rare complication of exposure to asbestos but are important to recognise. Other possible causes of upper lobe changes such as tuberculosis must always be excluded before the diagnosis is made.

Journal Article

Abstract  To evaluate the complaint of exertional dyspnea in asbestos-exposed shipyard workers, pulmonary function tests were performed at rest and during exercise on 90 subjects with pleural plaques. We divided the subjects into four groups based on resting pulmonary function studies. Group I subjects (eight) had a restrictive defect; group II subjects (30) had an obstructive defect; group III subjects (six) had an isolated reduction in diffusing capacity; and group IV subjects (46) had a normal study. Subjects with a restrictive defect demonstrated minor physiologic abnormalities during exercise. Subjects with an obstructive defect demonstrated abnormalities consistent with their obstructive defect. Subjects in groups III and IV demonstrated an abnormally elevated wasted ventilation fraction, which may be an early indicator of interstitial disease due to asbestos exposure. We believe exercise testing was a useful tool in excluding the presence of significant functional exercise limitation due to asbestos exposure in the majority of subjects and also in disclosing some physiologic abnormalities in some of the subjects in our study.

Journal Article

Abstract  The effects of asbestos-induced benign pleural conditions on pulmonary function have been controversial since this subject was first studied in the mid-1960s. Firm conclusions have been difficult to reach because of (1) the difficulty of taking into account asbestos exposure, which may have effects on pulmonary function other than those mediated through pleural lesions, (2) the disagreement over the type and extent of radiographic pleural abnormalities, (3) the imprecision in measuring pulmonary function, and (4) the numerous potential confounding factors of reduced pulmonary function, such as cigarette smoking, age, concurrent occupational exposures, and prior chest diseases or trauma. This article critically evaluates the published reports on the functional significance of asbestos-induced pleural conditions. The results of this analysis lead to the conclusion that (1) pleural plaques are not associated with clinically significant reductions in pulmonary function, (2) diffuse pleural thickening, when extensive, can severely impair ventilation, and (3) restriction with a preserved diffusing capacity is the expected pattern when pleural lesions are responsible for reduced pulmonary function.

Journal Article

Abstract  Fifteen of 71 women (21.1%) who had worked in shipyards before May, 1961 had radiographic signs of asbestos disease. There were irregular opacities in the lung parenchyma in seven and pleural disease in eight, two of whom had pleural calcifications. The 71 women who volunteered to be studied had a mean age of 61.5 years. Chronic bronchitis was diagnosed in 21%, 71% had dyspnea on climbing two flights of stairs, and 42% had wheezing. These prevalences were 50% higher than in wives of shipyard workers. In 50 white women, mean values for expiratory flow rates, log (FEF25-75) and log (FEF75-85), were decreased for non-, ex- and current smokers as compared to normal nonsmokers. Ex-smokers and current smokers showed the greater effects. Diffusing capacity (DLCOsb) and alveolar volume (ALV) were also reduced in all three smoking categories. Comparison to a reference population without asbestos exposure showed that for current, ex- and nonsmoking subgroups, there were significant reductions in log (FEF25-75), DLCOsb, and ALV for nonsmokers, reductions in FEV1, log (FEV25-75), and log (FEF75-85) in ex-smokers, and reduced ALV in current smokers. These decreases may reflect a locality effect. Further studies are recommended.

Journal Article

Abstract  Clinical study of 42 cases of pleural plaques occurring in Sweden from 1961-1967. The frequency of pleural plaques is found to be greatest among workers in the construction industry and workshops where temporary and irregular use of asbestos containing work materials has occurred. The long latency period following asbestos exposure before pleural plaques are observed reduces the value of pleural plaques as a sign of asbestosis. Strict commercial and technical control of the use of asbestos is recommended.

WoS
Journal Article

Abstract  The Nevoria deposit (production 11.88 t Au, 0.41 t Ag) is one of more than 20 gold skarns mined in the 3.1 to 3.0 Ga Southern Cross greenstone belt. The belt constitutes part of the continental foreland of the 2.7 to 2.6 Ga Norseman-Wiluna fold belt, the youngest Archean orogen of the Yilgarn craton. The Nevoria skarns are confined to iron formations at the limb of a regional F, anticline bent around the Ghooli orthogneiss dome. The refolding (F-2) took place at 2775 to 2724 Ma during batholith emplacement and contact metamorphism at estimated P-T conditions of 610degrees +/- 50degreesC and 400 +/- 100 MPa (14-km burial depth). This structural setting differs from that of the mezozonal lode gold deposits in the adjacent fold belt, which are controlled by fault-vein arrays in crustal-scale shear zones. The Nevoria orebodies (6-7 g/t Au), composed of pyrrhotite-rich hedenbergite-actinolite and almandine-hornblende skarns, are dated by a concordant U-Pb age (2635.7 +/- 1.2 Ma) and by a less precise Pb-Pb errorchron age (2630 +/- 13 Ma, MSWD = 5.9, n = 7), both defined by allanite-bearing almandine and by cogenetic scheelite. These ages demonstrate that the skarns formed 90 m.y. after amphibolite-facies metamorphism in the Southern Cross greenstone belt and at least 20 m.y. after transpressional faulting related to late-orogenic deformation in the Norseman-Wiluna fold belt. The peak fluid temperature during skarn formation is estimated at 550degrees to 600degreesC, based on the Fe-Mg exchange thermometry of almandine-biotite and almandine-hornblende pairs. Calcic-potassic mineral assemblages in skarn hosted by amphibolite constrain the pressure to 300 to 400 MPa, based on the reaction of biotite + cummingtonite + anorthite to almandine + grossular + biotite. The pressure estimate confirms that the Nevoria deposit formed at considerable depth (11-14 km) in a midcrustal environment. Substantial uplift did not take place until 2565 25 Ma, when biotite in the associated granite closed to Rb-Sr diffusion at 300degreesC ambient temperature. The Nevoria orebodies are cut by pegmatite dikes and are underlain by a 500-m-thick pluton of peraluminous two-mica granite. The concordant zircon U-Pb age (2634 4 Ma) of the granite is indistinguishable from the age of the skarn. The abundance of pegmatite in the main intrusion, increasing upward to a more than 80-m-thick roof zone, indicates that an aqueous fluid separated from the melt. The enrichment of aluminum, Au, As, Bi, Cu, Nb, W, and Zn in the upper pegmatite suggests that these elements were transported to the roof by an early magmatic fluid (700degrees-600degreesC), prior to the development of disseminated muscovite-epidote-carbonate alteration at a lower temperature (400degreesC). The major and trace elements elevated in the pegmatite are also enriched in the ore skarn, implicating the granite as the fluid source. Fluid inclusion data indicate that the magmatic fluid was CO2 bearing, aqueous, and of moderate salinity (about 10 wt % CaCl2 + NaCl equiv). Gold skarn formed in the iron formations above when the infiltrating fluid became progressively reduced during the replacement of grunerite. Other gold skarn deposits in the continental foreland of the Norseman-Wiluna fold belt show a similar space-time relationship to differentiated I-type granites (Thornton-Tuttle index >90). These granites (2.66-2.62 Ga) postdate the compressional deformation in the fold belt and are thus classified as postorogenic. The scheelite-bearing Archean gold skarns share characteristic features such as gangue-sulfide mineralogy and granite association with the deep-seated (150-250 MPa), reduced tungsten skarns located on the continental side of the North American Cordillera. Cretaceous deposits such as MacTung contain up to 2 g/t gold, locally.

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Journal Article

Abstract  The possible cause and sources of enhanced ozone at upper tropospheric equatorial Africa, observed by cruise Measurements of OZone by Airbus In Service Aircraft (MOZAIC) during the Northern Hemisphere winter in 1996 and 1997 on flight routes from Johannesburg to Vienna, are investigated. Two enhanced ozone events over upper tropospheric equatorial Africa are identified from MOZAIC observations on April 6, 1996 and March 27, 1997. High resolution ECMWF reanalysis GOME ozone has exhibited enhancement as well during these periods suggesting that the two events are not isolated small scale events but part of a larger scale process. As a result, the source and mechanisms of ozone increase over the region are further analysed using reanalysis data from ECMWF, outgoing long wave radiation (OLR) from NOAA and Meteosat images from NASA, International Satellite Cloud Climatology Project. Equivalent latitude computed from potential vorticity has shown that massive mid- and high-latitude stratospheric ozone rich airmass is funnelled into lower latitude troposphere through troughs extending from large amplitude planetary waves towards equator. The Space-time Fourier decomposition of meridionally averaged zonal wind has revealed that these planetary wave activities are linked to waves with zonal wavenumber 1-2, which prevail during Northern Hemisphere winter. Additional analysis to understand the mechanisms of ozone enhancement was made using Multitaper Method Singular Value Decomposition (MTM-SVD) spectral approach. The analysis confirms that ozone enhancement over the region is dependent on the relative position of positive PV and direction of wind anomalies. The high relative humidity measured simultaneously with ozone onboard MOZAIC, Meteosat imageries and circulation during the events have shown presence of deep convection. The coherent variation of OLR and ozone found over 8-day temporal cycle determined from MTM-SVD has indicated existence of OLR negative forcing in the upper troposphere and positive forcing in the lower stratosphere. These results show coupling of PV intrusion and deep convection over continental equatorial Africa in the same manner as the climatologically preferred intrusion over mid-ocean in eastern pacific. Moreover, the results enrich previous understanding with purely observational high resolution MOZAIC and ERA-Interim datasets, and statistical method. (C) 2013 Elsevier Ltd. All rights reserved.

Journal Article

Abstract  BIOSIS COPYRIGHT: BIOL ABS. RRM CASE STUDY HUMAN CARCINOGEN DYSPNEA TUMOR EXCISION FUSIFORM CELL DIAGNOSIS COMPUTED TOMOGRAPHY HISTOLOGY

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Journal Article

Abstract  The prograde deserpentinized peridotites from the talc zone in the Happo-O'ne complex, central Japan, show differences in their field relation and mineral assemblage with the high-P retrograde peridotites of the other part of the complex. They show a mineral assemblage, olivine + talc + antigorite +/- prograde tremolite +/- chlorite, formed by thermal metamorphism around the granitic intrusion at T, 500-650 degrees C and P< 7 kbar. The olivine has numerous opaque inclusions and high Fo (91.5-96.5) relative to the retrograde olivine, reflecting its formation by deserpentinization. The prograde tremolite, which is low in Al(2)O(3) (<1.0 wt.%), Cr(2)O(3) (<0.35 wt.%), and Na(2)O (<0.6 wt.%) but high in Mg# (up to 0.98) and SiO(2) (up to 59.9 wt.%), is different in size, shape and chemistry from the retrograde tremolite. The prograde peridotites display a U-shaped REE pattern (0.02-0.5 times PM), similar to diopside-zone retrograde metaperidotites, possible protoliths. They are enriched in LILE (e.g., Cs, Pb, Sr, Rb) relative to HESE (e.g., Ta, Hf, Zr, Nb), like their protoliths, because of their local re-equilibration with the fluid released during dehydration of the protoliths. They have high contents of REE and some trace elements (e.g., Cs, Th, U, Ta) relative to their protoliths because of an external-element addition from the granitic magma. In-situ analyses of peridotitic silicates confirmed that the prograde tremolite and talc display a spoon-shaped primitive mantle (PM)-normalized REE pattern (0.1-3 times PM) in which LREE are higher than HREE contents. The prograde tremolite is depleted in Al, Na, Cr, Sc, V. Ti, B, HREE and Li, but is enriched in Si, Cs, U, Th, HFSE (Hf, Zr, Nb, Ta), Rb and Ba relative to the retrograde tremolite; the immobile-element depletion in this tremolite is inherited from its source (antigorite + secondary diopside), whereas the depletion of mobile elements (e.g., Li, B. Na, Al) is ascribed to their mobility during the deserpentinization and/or the depleted character of the source of tremolite. The enrichment of HESE and LILE in the prograde tremolite is related to an external addition of these elements from fluid/melt of the surrounding granitic magma and/or in situ equilibrium with LILE-bearing fluid released during dehydration of serpentinized retrograde metaperidotites and olivine-bearing serpentinites (protoliths). The prograde olivine is higher in REE and most trace-element contents than the retrograde one due to the external addition of these elements; it is enriched in B, Co and Ni, but depleted in Li that was liberated during deserpentinization by prograde metamorphism. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.

Journal Article

Abstract  BACKGROUND: Millions of people worldwide are exposed to arsenic-contaminated water. In the largest city in northern Chile (Antofagasta) >250,000 people were exposed to high arsenic drinking water concentrations from 1958 until 1970 when a water treatment plant was installed. Because of its unique geology, limited water sources, and good historical records, lifetime exposure and long-term latency patterns can be assessed in this area with better accuracy than in other arsenic-exposed areas worldwide. METHODS: We performed a population-based case-control study in northern Chile from October 2007 to December 2010 involving 232 lung and 306 bladder cancer cases and 640 age- and gender-matched controls, with detailed information on past exposure and potential confounders, including smoking and occupation. RESULTS: Bladder cancer odds ratios for quartiles of average arsenic concentrations in water before 1971 (<11, 11-90, 91-335, and >335 µg/L) were 1.00, 1.36 (95% confidence interval, 0.78 to 2.37), 3.87 (2.25 to 6.64), and 6.50 (3.69 to 11.43), respectively. Corresponding lung cancer odds ratios were 1.00, 1.27 (0.81 to 1.98), 2.00 (1.24 to 3.24), and 4.32 (2.60 to 7.17). Bladder and lung cancer odds ratios in those highly exposed in Antofagasta during 1958-70 but not thereafter were 6.88 (3.84 to 12.32) and 4.35 (2.57 to 7.36), respectively. Conclusions and Impact: The lung and bladder cancer risks that we found up to 40 years after high exposures have ended are very high, and suggest that prevention, treatment, and other mortality reduction efforts in arsenic-exposed countries will be needed for decades after exposure cessation.

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Journal Article

Abstract  This work deals with investigations on effect of chemically and thermally resistant carbon fibre (CF) additives of various mechanical treatment on structure formation and properties of autoclaved aerated concrete (AAC). It was established that various methods of CF crushing, such as mixing with sand pulp, chopping, grounding, milling in dry way, milling in wet way cause different fineness of disintegrated CF particles and that along with increase in fineness, the crystallinity of AAC binding material is growing what leads to the following: increase in compressive strength by 6-22%; after exposure at temperature of 700 C, decrease in thermal deformation by 5-20%; decrease in mass loss by 7-20%. Upon addition of mechanically not treated CF of 0.1%, the flexural strength increases by 29% versus that of AAC without CF additive. The effect of added mechanically treated CF on flexural strength is less than that of not treated CF. Due to increased CF fineness, the flexural strength increment drops from 21% to 4%. Basing on the results obtained, one can draw a conclusion that CF particles resulted in mechanical treatment have an activated surface and can serve as nuclei of crystallization during the hardening of AAC binding material, which contains a mechanically treated CF additive, thus causing increase in crystallinity of hardened binding material and, consequently, improved performance of AAC. (C) 2011 Elsevier Ltd. All rights reserved.

Journal Article

Abstract  This paper presents the hydrochloric attack of serpentinites. Romanian serpentinites are part of the Danubian crystalline complex. These serpentinites contain mineral serpentine (magnesium silicate) and a small amount of other minerals along with calcium, iron, aluminium, nickel, cobalt, chrome and manganese. For processing, the serpentinite was attacked by hydrochloric acid from two provinces (p.a. and residual hydrochloric acid), using different experimental conditions: acid concentrations between 15-23 per cent HCl, the temperature range of 70-90 degrees C, with stoichiometric ratio between reactants and with acid excess, the extraction time being up to 180 min. In optimum conditions, the magnesium extraction is almost total (99.5 per cent). A well-balanced processing of these serpentinites looks for both the silica residue utilization and the chloride solutions, in order to separate the prevalent magnesium as well as the valuable microcomponents--nickel and cobalt.

Journal Article

Abstract  Interstitial pneumonia develops in association with inhaled particles. In-air microparticle induced X-ray emission (in-air micro) analysis was previously employed to assess the spatial distribution and content of particles in surgical lung biopsy specimens. The aim of this study was to assess the efficacy of in-air micro-analysis for transbronchial lung biopsy specimens in patients with or without occupational exposure. The elements composing lung particles and their locations could be identified by in-air micro-analysis. Silicon was the major component of particles. Quantitative analysis revealed that the elements composing lung particles varied between patients. In a patient with suspected nickel exposure, aluminium, vanadium, and calcium were detected, but was not detected. In a patient without a work history (housewife), various elements were detected. In-air micro-analysis was useful for assessing the spatial distribution and content of particles in specimens from patients. Occupational exposure was not necessarily associated with deposition of particles in the lungs. Therefore, in the diagnosis of, elemental analysis of specimens by in-air micro-analysis could be useful for assessing exposure to particles objectively.

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