Asbestos content in the lymph nodes of nonoccupationally exposed individuals

Background The thoracic lymph nodes are a part of the clearance system from lung tissue. Accumulation of dust in these nodes are known to occur follow ing some types of exposure. However, no information exists as to asbestos c ontent in lymph nodes from the general population. Methods The study cohort consisted of 21 individuals previously defined as nonoccupationally exposed to asbestos. Tissue burden of asbestos obtained f rom lung analysis by analytical electron microscopy was compared with burde n in the lymph nodes, Results No asbestos fibers were detected in nodes from 8 cases. The majorit y of the fibers found in lymph nodes were short (<5 mu m) and most often no ncommercial amphiboles. Ferruginous bodies (FBs) were detected in lymph nod e from only two samples, Conclusions The total asbestos burden in the lung tissue from these individ uals was quite low However, in 12 of the 13 cases that had positive nodes, the tissue burden in the node was appreciably heavier per gram than in the lung. This raises the question as to whether the lymph nodes, though less e fficient clearance, may be better indicators of lifetime exposure to dust t han lung tissue. (C) 2000 Wiley-Liss, Inc.