Beryllium abnormalities

The small lithium Li" and beryllium Be ions have high charge-radius ratios and consequently exert particularly strong attractions on other ions and on polar molecules. These attractions result in both high lattice and hydration energies and it is these high energies which account for many of the abnormal properties of the ionic compounds of lithium and beryllium. 

The abnormal properties of lithium and beryllium are summarised in Tables 6.5 and 6.6. 

The specific heat at ordinary temperatures is abnormal as in the case of boron, carbon and silicon, but Humpidge (1885 i, 1886 i) has shown that between 400° and 500° it remains practically constant at about 0.62. The matter was one of long controversy and the low results obtained by Nilson and Fetters-son (1878 3) and others was the chief cause of the belief in the trivalency of beryllium. According to Humpidge (1885 i and 6, 1886 i) the relation between specific heat and temperatures can be expressed by the empirical formula ... 

Immunologic Sensitivity to beryllium was investigated among 362 workers at an aluminium smelter in Norway [40 ]. One had abnormal results in two separate blood samples and was sensitized to beryllium. Three others had one abnormal test that was not confirmed by a second test. One of a control group of 31 people had one abnormal and one normal test result. This frequency of beryllium sensitivity is much lower than is found in the beryllium handling industry, which the authors attributed to lower atmospheric concentrations, beryllium speciation effects, or the use of respiratory protective equipment. 

Beryllium exposure has been studied in 3185 workers from nine aluminium smelters owned by four different aluminium-producing companies, of whom 1932 workers participated in medical surveillance programs that included the serum beryllium lymphocyte proliferation test, confirmation of sensitization by at least two abnormal test results, and further evaluation for chronic beryllium disease in workers with beryllium sensitivity [41 ]. Nine workers had beryllium sensitivity (prevalence rate = 0.47%, 95% CI = 0.21, 0.88). The authors attributed the low rate of sensitization in aluminium smelters to the more soluble form of beryllium found in the aluminium smelting work environment and the consistent use of respiratory protection. 

The use of the blood BeLPT has defined a subset of exposed workers who develop an adaptive immune response to beryllium, but in whom there are no pathologic or clinical features of CBD. These individuals are asymptomatic and have normal pulmonary function, exercise tolerance, chest radiographs, and lung biopsies. Although their blood BeLPT is abnormal, they have not yet developed a clinically detectable inflammatory process in the lung. The rate of beryllium sensitization without disease in a few published smdies has ranged from 1% to... 

The consensus BeLPT method uses challenge of peripheral blood mononuclear cells with three incremental doses of beryllium sulphate solution at two different culture periods, thus providing six different responses for analysis. Tritiated thymidine is added to cultures 1 day prior to harvest, and uptake of radio-labelled thymidine is measured as counts per minute with a beta counter. Final results are expressed as a stimulation index (SI), where the mean counts per minute of control (beryllium-free) cultures are divided into the mean counts per minute of each beryllium-exposed culture. The test is interpreted as abnormal if an SI of 3.0 or higher occurs in two of six beryllium-exposed cultures. An SI of 3.0 or higher in one of six cultures is considered borderline, and a SI of 3.0 or higher in zero of six cultures is considered negative. The least-absolute-values method of statistical analysis has been proposed as a means to improve identification of borderline and abnormal BeLPT results (Frome et al. 2003). 

Frome EL, Newman LS, Cragle DL et al (2003) Identification of an abnormal beryllium lymphocyte proliferation test. Toxicology 183 39-56... 

Chronic beryllium disease Adenopathy, nodules, ground glass abnormality... 

Fig. 10.1. Chest radiograph in a patient with advanced chronic beryllium disease shows abnormality predominating in the upper lobes, consisting of coarse well-defined nodules, which appear to coalesce in areas. Some of the nodules appear calcified. There is moderate upper lobe volume loss with superior hilar retraction and some anatomic distortion. Hilar enlargement is likely due to a combination of adenopathy and pulmonary arterial enlargement due to pulmonary hypertension...

Fig. 10.8. Thin-section computed tomography through the mid-lungs in a patient with chronic beryllium disease shows marked airway wall thickening and mild, predominantly peri-bronchovascular, ground glass abnormality...

Beryllium exposure occurs in a wide variety of occupations. It may cause acute berylliosis (currently very rare), beryllium sensitization, chronic beryllium disease, or lung cancer. Imaging manifestations of chronic beryllium disease are generally similar to those of sarcoidosis, with nodules, ground glass abnormality, septal thickening, conglomerate masses, and mediastinal or hilar lymphadenopathy. 

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