Characteristics of asbestos concentration in lung as compared to asbestos concentration in various levels of lymph nodes that collect drainage from the lung.
Inhaled dust particulates are able to relocate to the extrapulmonary compartments, particularly the lymph nodes that drain the lung. There is little information about the concentration and type of asbestos in the lymphatics and lymph nodes. Quantitative analysis of asbestos lymph node burden conducted by light and analytical transmission electron microscopy has shown ferruginous bodies in lymph nodes that drain the lung and appreciable numbers of short asbestos fibers accumulate in lymph nodes in occupationally exposed individuals. The location of lymph nodes in the thoracic cavity was categorized according to the Naruke anatomical map. Tissue from eleven individuals with a history of asbestos exposure were selected for a comparative study of the asbestos content of lung with that found in the thoracic lymph nodes. The study used a digestion technique for tissue preparation and evaluated ferruginous body burden and concentration of asbestos fibers (> 0.5 microm in length). Comparison was made between sites and analysis was made as to the population of fibers detectable by light microscopy and defined as "Stanton fibers." The findings indicated the vast majority of all asbestos fiber types in all sites were shorter than 5 microm and would not have been counted in a light microscopy count scheme that included only those fibers > 5 microm. There were reproducible patterns of asbestos types of found in various lymph nodes, although there were variations in the amount of asbestos found in the sites sampled. In summary, asbestos fibers found in thoracic lymph nodes have predominately short fibers and, in this study group, consisted of a mixture of commercial and noncommercial amphiboles. When a long/thin fiber was found in the lung or lymph tissue, its detection required the use of analytical transmission electron microscopy for identification.
Dodson
Ronald F
RF
Dodson Environmental Consulting, Inc. and ERI Analytical, Tyler, Texas, USA.
Shepherd
Sara
S
Levin
Jeffrey
J
Hammar
Samuel P
SP
D000368:Aged; D000369:Aged, 80 and over; D001194:Asbestos / Q000032:analysis*; D001195:Asbestosis / Q000378:metabolism / Q000473:pathology*; D001822:Body Burden; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000737:chemistry / Q000648:ultrastructure*; D008198:Lymph Nodes / Q000737:chemistry / Q000648:ultrastructure*; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D019016:Mineral Fibers; D016273:Occupational Exposure; D010316:Particle Size; D013909:Thorax
D019016:Mineral Fibers; D001194:Asbestos