Figure 7.

A schematic diagram showing a hypothesized mechanism of carcinogenesis due to frustrated phagocytosis. If left unabsorbed, long CNTs in cells can produce oxidative stress and induce inflammation. It has been suggested that a long period of persistent inflammation in the thoracic cavity following inhalation of CNTs can lead to carcinogenesis. Currently, research into the inhalation toxicity of CNTs is facing a problem with the determination of the margin of inhalation exposure that does not cause persistent inflammation.