ABSTRACT
Oxidative stress mechanisms appear to play an essential role in emphysema, fibrosis, and cancer processes resulting from inhalation of inorganic dusts. The presence of Fe(II) species, released in solution or appearing at the solid-liquid interface during leaching of the solid phase, leads to a sequence of reactions with dissolved molecular oxygen, generating strong electrophilic species (ferryl, perferryl). These play the role of the ultimate toxic species in cancer and emphysema. In phagocytic cells, some Fe(III) species, with appropriate ligands, can react with to produce Fe(II), which is able to react with H2O2 or O2 and to trigger a Fenton reaction in macrophages-the first step of the sequence leading to fibrosis.
