Ultrastructure of the Lungs of Dogs Exposed to Beryllium-Containing Dusts

Two beagle dogs were exposed by the natural respiratory route to rocket exhaust fumes containing beryllium oxide, beryllium fluoride, and beryllium chloride. The lung tissue was examined electron microscopically after a three-year post- exposure period. Beryllium particles and small agglomerates less than 1μ in size were deposited in iysosomes in the cytoplasm of histiocytes in the interstitium of the septa. They were closely associated with collagen bundles several microns wide and with increases in numbers of septal capillaries. The lesions were more typical of the classical reaction to a foreign-body than immunologic in character and represented an early form of chronic beryllium disease.