Beryllium

This document provides a listing of available sources that can be used to validate analytical methods and/or instrumentation for beryllium determination. A literature review was conducted of available standard methods and publications used for method validation and/or quality control. An annotated listing of the articles, papers, and books reviewed is given in the Appendix. Available validation documents and guides are listed therein; each has a brief description of application and use. In the referenced sources, there are varying approaches to validation and varying descriptions of the validation process at different stages in method development. This discussion focuses on validation and verification of fully developed methods and instrumentation that have been offered for use or approval by other laboratories or official consensus bodies such as ASTM International, the International Standards Organization, the International Electrotechnical Commission, and the Association of Official Analytical Chemists. This review was conducted as part of a collaborative effort to investigate and improve the state of validation for measuring beryllium in the workplace and the environment. Documents and publications from the United States and Europe are included.

Exogenous ochronosis is a cutaneous disorder characterized by blue-black or slate-gray hyperpigmentation resulting from the prolonged use of certain topical agents, most commonly hydroquinones. It is notoriously difficult to treat. To report the effectiveness of a quality-switched (QS) 755-nm alexandrite laser in treating hydroquinone-induced exogenous ochronosis. Hydroquinone-induced exogenous ochronosis in two patients was treated with a QS alexandrite laser. The first patient received six treatments (average fluence=7.8 J/cm(2)) at 2-month intervals. The second patient received four treatments (average fluence=6.9 J/cm(2)) at 4-month intervals. Biopsies of lesional skin were obtained before and after laser treatment for histologic evaluation. Significant lightening of the pigmented skin areas was achieved in both patients without scarring or textural changes. Decreased dermal pigmentation was observed on histologic examination of treated skin specimens. The QS alexandrite laser can effectively treat exogenous ochronosis without untoward side effects.

The transgenic heterozygous p53+/- knockout mouse has been a model for assessing the tumorigenicity of selected carcinogens administered by noninhalation routes of exposure. The sensitivity of the model for predicting cancer by inhaled chemicals has not been examined. This study addresses this issue by acutely exposing p53+/- mice of both sexes by nose-only inhalation to either air (controls), or to 1 of 2 levels of 239PuO2 (500 or 100 Bq 239Pu) or beryllium (Be) metal (60 or 15 μg). Additional wild-type p53+/- mice were exposed by inhalation to either 500 Bq of 239PuO2 or 60 μg of Be metal. These carcinogens were selected because they operate by differing mechanisms and because of their use in other pulmonary carcinogenesis studies in our laboratory. Four or 5 of the 15 mice per sex from each group were sacrificed 6 mo after exposure, and only 2 pulmonary neoplasms were observed. The remainder of the mice were held for life-span observation and euthanasia as they became moribund. S...

Background, aim and scope The paper presents concentrations of trace elements in blood of homebred animals (cows and sheep) from Southern Serbia (Bujanovac) and the contents of natural and anthropogenic radionuclides and some heavy metals in feed. The region of Southern Serbia was exposed to contamination by depleted uranium ammunition during NATO attacks in 1999 and therefore, is of great concern to environmental pollution and human and animal health. Materials and methods Conventional instrumental and epithermal neutron activation analyses are used to measure trace elements in cow and sheep blood samples collected randomly at six locations in the region of Bujanovac (village of Borovac) in the spring of 2005. Samples of feed (grass and crops: corn, wheat and oats), collected on the same locations (households), are analysed for the contents of radionuclides on an HPGe detector (Ortec, relative efficiency 23%) by standard gamma spectrometry. The content of Hg, Pb and Cd in feed is determined by standard atomic absorption spectrometry on the VarianSpectra220/ThermoSolar GFS97 spectrometer. Results Concentrations of 29 elements (Na, Al (P), Cl, K, Sc, Cr, Mn, Ni, Fe, Co, Zn, Se, As, Br, Sr, Rb, Sb, In, I, Ba, Cs, La, Nd, Eu, Sm, Tb, Hf, Ta and Th) are determined in blood of the examined animals. In feeds, natural 40K is found in all of the samples, cosmogenic 7Be and fission product 137Cs are detected only in the grass samples, while heavy metals Hg, Cd and Pb are found in the range of 0.01–0.02, 0.84–1.15 and 0.74–7.34 mg/kg, respectively. Calculated soil-to-blood transfer factors are in a wide range of 8·10−6 to 64, as a result of varying significance of the elements in animal metabolism and feeding habits. Discussion The results of trace elements’ concentrations in animal blood are in good agreement with available data for K, Ni, Zn, Se and Rb. Higher Br concentrations in animal blood are most probably caused by large biomass burning events during blood sampling. Very low concentration of Fe in cows and sheep confirms the results of previous biochemical studies on animal anaemia in the region. High concentration of As correlates with geochemical peculiarities of the Balkans and is also likely influenced by the use of pesticides in the agricultural production. For some of the elements (La, Nd, Eu, Sm, Tb, Sb, Hf, Ta, Th, In, Ba, Sr, Sc and Cs), there are few or no literature data. Therefore, some of the presented data are significant not only for the country and the region, but on a wider scale. Activities of natural radionuclides in feeds are within the average values reported for the region, while the activities of 210Pb and 235/238U are below the limit of detection. This is in accordance with previous investigations showing no widespread contamination by depleted uranium in the area. Contents of Hg and Pb in feeds are below the nationally permissible levels, unlike the content of Cd which exceeds it, probably caused by the use of phosphate fertilisers and fossil fuel combustion in the area. Conclusions In general, the concentrations of trace elements in blood of homebred cows and sheep are in good agreement with reference materials, available literature data and the results of previous studies in the area. The exceptions are Fe, As and Br. The contents of natural and anthropogenic radionuclides in feeds are within the expected levels, and there are no signs of contamination by depleted uranium or other fission products. Apart from Cd, there are no signs of pollution by heavy metals in feeds. The highly sensitive method of instrumental neutron activation analysis provides data on the concentration of some elements in animal blood not previously reported for the region and elsewhere. Recommendations and perspectives The presented study is a part of the long term ongoing project on the health risk assessment on animals and humans in the region. The collected data is intended to provide a base for the animal and human risk assessment as well as an estimate of the general pollution status of the environment in the region. Since some of the investigated elements are classified as important trace elements for livestock, the results could also be used to balance and improve the animal diet and thus, improve the growth and reproduction rate.

Recently [Nucl. Instr. and Meth. B 145 (1998) 277; Extraction of in-medium nucleon-nucleon amplitude from experiment, NASA-TP, 1998], we developed a method of extracting nucleon-nucleon (N-N) cross-sections in the medium directly from experiment. The in-medium N-N cross-sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the NASA Langley Research Center. We investigated [Proton-nucleus total cross-sections in coupled-channel approach, NASA/TP, 2000; Nucl. Instr. and Meth. B 173-174 (2001) 391] the ratio of real to imaginary part of the two body scattering amplitude in the medium. These ratios are used in combination with the in-medium N-N cross-sections to calculate proton-nucleus elastic cross-sections. The agreement is excellent with the available experimental data. These cross-sections are needed for the radiation risk assessment of space missions.

MkIIGB divertor tiles exposed in JET for the 1998–2001 and 1999–2001 campaigns have been used to assess the amount of beryllium and carbon deposited at the inner divertor wall. Total amount of Be at the inner divertor tiles was determined and integrated toroidally. Results were compared with data obtained with optical spectroscopy and good agreement was obtained. The amount of deposited C was computed from the amount of deposited Be assuming that the Be/C ratio arriving in the divertor is the same as the Be/C ratio in the main chamber. On the basis of this analysis we would expect there to be 0.4 kg of C deposited. This gives an average C deposition rate lower than during the MkIIA phase.

Berylliosis is a chronic granulomatous disorder caused by inhalation of Be dusts that is driven by the accumulation Be-specific CD4+ Th1-cells at disease sites. Susceptibility to berylliosis has been associated with the supratypic variant of HLA-DP gene coding for glutamate at ...