Fig. 3From: Assessment of the toxicity and carcinogenicity of double-walled carbon nanotubes in the rat lung after intratracheal instillation: a two-year studyLung sections of rats administered 0.5Â mg DWCNT at 52Â weeks (A) and 104Â weeks (B). The majority of the DWCNT is encapsulated in granulation tissue (arrows). The boxed areas are higher magnifications using a polarized lens showing DWCNT fibers. Lung sections of rats administered MWCNT (0.5Â mg) at 52Â weeks (C) and 91Â weeks (D). MWCNT-7 can be seen encapsulated inside granulation tissue. In contrast to DWCNT, free macrophages phagocytosing MWCNT-7 fibers are a common feature. The boxed areas are higher magnifications using a polarized lens showing MWCNT fibers in free macrophagesBack to article page