Orally ingested chrysotile asbestos affects rat lungs and pleura.

The authors designed this study to show the effects of orally ingested asbestos on the lungs and pleura. They designated 3 groups of rats: group A (n = 18) was given 1.5 g/L asbestos in water, group B (n = 18) was given 3 g/L asbestos in water, and group C (n = 15), as a control group, was given only water. Histopathological evaluation of lungs and pleura of the rats after 6 months revealed significant mesothelial proliferation and asbestos bodies. After 9 months, more rats exhibited mesothelial proliferation in group B than in group A (p < .05). The number of rats with asbestos bodies in their lungs was greater in group B than in group A. More rats in group B than in group A had asbestos in their spleen. The authors observed mesothelial proliferation in all group B rats at the end of 12 months. Ingested asbestos traveled from the gastrointestinal system to the lungs, likely via a lymphohematological route, leading to mesothelial proliferation, which may lead to malignancies.