Lung fibrosis associated with rare earth exposure.
Ruettner-JR; Spycher-MA; Vogt-P
NIOSH 1990 Nov; :1087-1088
An investigation was conducted on diffuse interstitial lung fibrosis observed in reprophotographers. Reprophotographers have been exposed to fumes occurring during the burning of carbon rods in large printing laboratories. After years of exposure the workers developed a slowly progressive dyspnea. From the nine patients reported, only three were diagnosed during life by lung biopsy as suffering from rare earth exposure. The average exposure time was about 31 years, the latency period was on the average 43 years. The techniques of analysis used included histology, transmission electron microscopy, energy dispersive X-ray analysis, selected area electron diffraction, and X-ray spectroscopy. Gross pathology in all autopsied cases of interstitial pulmonary fibrosis was similar and sometimes difficult to assess. Microscopically the prominent features included marked interstitial fibrosis with mild interstitial infiltration. Lobular and interlobular septa were fibrosed and occasionally revealed proliferation of smooth muscle cells. Interstitial infiltrates of macrophages containing small nonbirefringent particles less than 10 micrometer were present and there was perivascular accumulation of small deposits of dust particles. In alveolar macrophages as well as in extracellular interstitial spaces, electron dense irregular deposits ranging from packed rodlike mineral particles 0.01 micrometers in diameter and 0.1 micrometer in length.
Body-burden; Tissue-distribution; Mineral-dusts; Chemical-analysis; Respiratory-system-disorders; Lung-burden; Dust-inhalation; Lung-disease
DHHS (NIOSH) Publication No. 90-108
Proceedings of the VIIth International Pneumoconioses Conference