Among various
beryllium (Be) compounds,
beryllium oxide (BeO) has so far been noted as a causative substance which introduce chronic pulmonary
berylliosis. In our study, chronic pulmonary
berylliosis was experimentally evoked by using two species of BeO with individual purity and fired temperature (A group: 95.0% in purity, and 1,300 degrees C or above in fired temperature, B group: 99.9% in purity, and 800-1,000 degrees C in fired temperature), and demarcation of prepared Be concentration involving in the genesis of the disorder was examined. BeO with various concentrations ranging from 200 micrograms to 0.1 micrograms were mixed with 0.1%
agar solution and infused into right thorax cavity of male guinea pig, following which variation of the
body weight was checked and pulmonary histo-pathological findings, peripheral hematological tests, and sero-biochemical tests were carried out on a periodical basis at 8 weeks, 16 weeks, and 32 weeks. The results obtained are outlined herein. 1)
Body weights of test animals in both A group and B group were significantly decreased as compared with that of the control. 2) Pulmonary histo-pathological findings revealed the genesis of epitheloid-cell
granuloma in the lungs where non-infusion sides were included, which resembled to non-caseating
granuloma in the human pulmonary
berylliosis. 3) The frequency in the genesis of epithelaid-cell
granuloma was 1/36 (2.8%) in A group and 4/35 (11.4%) in B group,
granuloma formation being marked in the latter. 4) Examination of the frequency in terms of BeO dosages revealed no results suggesting the dose-response relationship between pulmonary
granuloma formation and the dosage. 5) There were no changes worthy of note in peripheral hematological tests. 6) Sero-biochemical tests revealed that
alkaline phosphatase value together with total
protein in each was significantly decreased in B group at 32 weeks following the infusion.