Beryllium In Air Research Articles

Analytical Possibilities of Detecting Trace Quantities of Beryllium by ERIAD Mass-Spectrometry

The possibility of mass-spectrometric determination of the beryllium concentration in the air in work rooms is examined. Experiments have shown that the ERIAD ion source (electro-sprayng with controlled atomization in the source) gives the required rapid-analysis of the beryllium content, including at a level 10 times lower than the maximum admissible concentration. Evaluations show that such analysis takes no more than 30 min, including sample preparation; one mass-spectrometer can service 10‐12 sampling points. The aim of the present work is to determine the possibility of using mass-spectrometry with the ERIAD ion source (electrospraying controlled fragmentation and atomization of ions in the source) for fast determination of small concentrations of beryllium in air. Beryllium is an important material used in metallurgy as an alloying additive and in modern microelectronics and the nuclear industry. Its yearly production is several tens of tons, and the demand for it is constantly growing. Beryllium is a toxic element. Strict standards allowing a maximum concentration not exceeding 10 ‐6 g/m 3 in air in a work zone, where it usually exists as an oxide or salts adsorbed on dust particles, have been adopted in our country. There are significant difficulties in sensor monitoring of these requirements: the methods adopted entail multistage sample preparation, including concentrating the samples and chemical release [1]. This method does not permit fast analysis of the beryllium content in air, which in the case of possible accidents or arbitrary emissions can have serious consequences. The conventional optical methods of analysis with excitation of the atoms in inductively coupled plasma or spark excitation are ineffective for detecting trace quantities of beryllium because of the small number of optical lines and their considerable overlapping with the lines of other elements. In practice, a concentration below 50 ppm cannot be determined adequately by these methods without preliminary concentration. Mass-spectrometry has a considerable advantage over other methods of analysis used for detection and quantitative determination of the beryllium concentration because there are no lines of other chemical elements in the region of the mass spectrum where its atomic line lies (9 amu). However, difficulties arise when the beryllium atoms are ionized. For example, surface ionization is ineffective because the ionization potential of beryllium atoms is high (>9 eV); mass-spectrometry with inductively coupled plasma creates a significant spread of the ions at the exit from the source. It is reduced by using a cool

Migration of Beryllium via Multiple Exposure Pathways among Work Processes in Four Different Facilities

Inhalation of beryllium is associated with the development of sensitization; however, dermal exposure may also be important. The primary aim of this study was to elucidate relationships among exposure pathways in four different manufacturing and finishing facilities. Secondary aims were to identify jobs with increased levels of beryllium in air, on skin, and on surfaces; identify potential discrepancies in exposure pathways, and determine if these are related to jobs with previously identified risk.Beryllium was measured in air, on cotton gloves, and on work surfaces. Summary statistics were calculated and correlations among all three measurement types were examined at the facility and job level. Exposure ranking strategies were used to identify jobs with higher exposures.The highest air, glove, and surface measurements were observed in beryllium metal production and beryllium oxide ceramics manufacturing jobs that involved hot processes and handling powders. Two finishing and distribution facilities that handle solid alloy products had lower exposures than the primary production facilities, and there were differences observed among jobs. For all facilities combined, strong correlations were found between air-surface (rp ≥ 0.77), glove-surface (rp ≥ 0.76), and air-glove measurements (rp ≥ 0.69). In jobs where higher risk of beryllium sensitization or disease has been reported, exposure levels for all three measurement types were higher than in jobs with lower risk, though they were not the highest. Some jobs with low air concentrations had higher levels of beryllium on glove and surface wipe samples, suggesting a need to further evaluate the causes of the discrepant levels.Although such correlations provide insight on where beryllium is located throughout the workplace, they cannot identify the direction of the pathways between air, surface, or skin. Ranking strategies helped to identify jobs with the highest combined air, glove, and/or surface exposures. All previously identified high-risk jobs had high air concentrations, dermal mass loading, or both, and none had low dermal and air. We have found that both pathways are relevant.[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a file describing the forms of beryllium materials encountered during production and characteristics of the aerosols by process areas.]

Exposure Pathway Assessment at a Copper–Beryllium Alloy Facility

Controlling beryllium inhalation exposures to comply with regulatory levels (2 micro g m(-3) of air) does not appear to prevent beryllium sensitization and chronic beryllium disease (CBD). Additionally, it has proven difficult to establish a clear inhalation exposure-response relationship for beryllium sensitization and CBD. Thus, skin may be an important route of exposure that leads to beryllium sensitization. A 2000 survey had identified prevalence of sensitization (7%) and CBD (4%) in a beryllium alloy facility. An improved particulate migration control program, including dermal protection in production areas, was completed in 2002 at the facility. The purpose of this study was to evaluate levels of beryllium in workplace air, on work surfaces, on cotton gloves worn by employees over nitrile gloves, and on necks and faces of employees subsequent to implementation of the program. Over a 6 day period, we collected general area air samples (n = 10), wipes from routinely handled work surfaces (n = 252), thin cotton glove samples (n = 113) worn by employees, and neck wipes (n = 109) and face wipes (n = 109) from the same employees. In production, production support and office areas geometric mean (GM) levels of beryllium were 0.95, 0.59 and 0.05 micro g per 100 cm(2) on work surfaces; 42.8, 73.8 and 0.07 micro g per sample on cotton gloves; 0.07, 0.09 and 0.003 micro g on necks; and 0.07, 0.12 and 0.003 micro g on faces, respectively. Correlations were strong between beryllium in air and on work surfaces (r = 0.79), and between beryllium on cotton gloves and on work surfaces (0.86), necks (0.87) and faces (0.86). This study demonstrates that, even with the implementation of control measures to reduce skin contact with beryllium as part of a comprehensive workplace protection program, measurable levels of beryllium continue to reach the skin of workers in production and production support areas. Based on our current understanding of the multiple exposure pathways that may lead to sensitization, we support prudent control practices such as use of protective gloves to minimize skin exposure to beryllium salts and fine particles.

Measurement of beryllium in lung tissue of a chronic beryllium disease case and cases with sarcoidosis.

The clinical features of chronic beryllium disease (CBD) are similar to many other chronic lung diseases. In particular, it may be difficult to distinguish it from pulmonary sarcoidosis since the two conditions may be very alike in clinical, pathological and radiological features. Aim To determine if the amount of beryllium found in the lungs could be used to differentiate CBD from sarcoidosis and controls. Analyses for beryllium in the autopsied lung tissues of 29 cases and controls were carried out. The cases included one CBD, three confirmed sarcoidosis and 25 controls. Blocks of formalin-fixed tissues were analysed by an atomic absorption spectrophotometer equipped with a graphite furnace. A method for analysis of beryllium in air was modified to permit tissue analysis. The CBD case had a much higher average beryllium level, but some individual results were similar to controls and patients with sarcoidosis. The CBD case had beryllium levels within the range of values reported in the literature. The differentiation between CBD and sarcoidosis could not be made with reasonable assurance based only on the analytic result. Occupational history is very important in making a diagnosis of CBD, along with the analysis of tissues. Tissue analysis helped confirm the diagnosis of compensatable CBD in this particular case.

Secondary emission of beryllia on beryllium

Thin layers of beryllia (BeO) were formed on beryllium (Be) substrates by oxygen-ion bombardment, heating beryllium in air, and by sputtering BeO. The secondary yield (from both secondary and backscattered electrons) was measured relative to BeO thickness and the contaminants present. The carbon content substantially reduces the yield and an expression was introduced to estimate the effect of other low-yield participants. The voltage for highest yield increased with BeO thickness, the yield versus voltage curves were also shown to be dependent on BeO thickness and exhibited sharp maxima. At greater thicknesses, surface voltage charging was suspected but investigation showed that this was not the case.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Detection of beryllium by laser-induced-breakdown spectroscopy

Using the new technique of laser-induced-breakdown spectroscopy (LIBS) a limit of detection was measured for beryllium in air of 0.5 ng g ( w w ), which is one-third of the OSHA limit for the 8-h average exposure to beryllium. Approximately linear working curves were obtained over the concentration range 0.5 to 2 × 10 4 ng g −1. The potential application of this technique to a beryllium monitoring instrument is discussed.

Spectrophotometric determination of beryllium in air by a sensitised Chrome Azurol S reaction.

Spectrophotometric determination of beryllium in air by a sensitised Chrome Azurol S reaction.

Rapid determination of beryllium by a direct-reading atomic absorption spectrophotometer.

Abstract A sensitive and specific analytical method for beryllium in air, swipe, biological, and packing material samples was developed. A single-beam atomic absorption spectrophotometer and high-temperature nitrous oxide-acetylene flame is used. The chemical technique for sensitivity enhancement and decontamination from radionuclides is described. Maximum time expenditure for an analysis is less than 30 minutes. Multiple samples may be run in the same time period. Sensitivity of the method is less than 0.04 parts per million of beryllium with a repeatability of approximately 2% of the amount present. Decontamination factors for uranium and transuranium elements were greater than 5000.

SPECTROGRAPHIC DETERMINATION OF BERYLLIUM IN AIR, BIOLOGICAL MATERIALS, AND ORES USING THE SUSTAINING A.C. ARC.

Abstract A spectrographic method has been developed, using a sustaining a.c. arc, for the quantitative determination of beryllium in amounts as low as 0.001 microgram. The method is based upon the excitation of beryllium volatilized from a chloride matrix which is prepared from a lithium chloride-graphite buffer, liver ash, and the ashed or fused sample. Experiments with Be7 have provided quantitative recoveries of the radioactive tracer from urine samples and from bertrandite and beryl ores. Application of the method to samples of beryllium ores provided, in six out of eight cases, less than 10% deviations from the results of the chemical analyses reported by the U. S. Bureau of Mines.

Spectrophotometric determination of beryllium in air and dust

The requirements of beryllium monitoring are discussed. Emphasis is placed on developing an Analytical procedure which is rapid, simple to operate, of adequate sensitivity and of reasonable accuracy. For air analysis, beryllium bearing dust is collected on a membrane filter, the beryllium is obtained in solution and determined spectrophotometrically, using aurine tricarboxylic acid (aluminon) as reagent Interference due to other metals is avoided by the addition of suitable complexing agents. A sensitivity of 0 1 μg Be can be achieved

Structure and growth of beryllium oxide on single crystal of beryllium

The nature of the structure and growth of BeO films formed by heating single crystals of beryllium in air over a wide range of temperatures was studied in detail using electron diffraction, and electron microscopy. The epitaxial nature of the oxide formed in the temperature range 300 deg C to 400 deg C on a Be (001) cleavage face was established. In the case of electropolished (001) surfaces of beryllium, it was found that the epitaxial BeO overgrowth was less well-defined. It was suggested that this disorientation was due to the formation, during the electropolishing procedure, of surface elements other than (001) upon which the oxide could grow. Onedegree (103)-oriented BeO was observed on (100) and (110) faces of Be. The oxidation rate increased with increase in temperature, resulting in a corresponding increase in the proportion of randomly-oriented BeO until, above 600 deg C, only random growth was observed in the upper regions of the layer. At about 800 deg C, a pronounced (001) habit of the randomly-oriented BeO crystals was developed. The diameter of the oxide crystals was estimated from the diffraction patterns to be some tens of Angstroms below 300 deg C, and in the order of thousandsmore » of Angstroms at about 800 deg C. The non-protective nature of the oxide layer formed at 600 deg C and above, is evident from the electron micrographs which showed the development of projecting needles of BeO up to 5 mu in length and several hundred Angstroms in thickness. The needles possessed a (110) axis, and possibly grew around screw dislocations. Thin BeO flakes up to several mu in dianneter were also observed in this temperature range, the diffraction pattern indicating considerable distortion of the flake. (auth)« less