Figure 9.

Scheme of metal mixture transformation process in Balb c/3T3. We show that damage to macromolecules (lipids and DNA) occurs the first day of initiation phase with no change in cell viability, suggesting that DNA repair systems may have been impaired by the metal mixture treatment (2 μM NaAsO₂, 2 μM CdCl₂, and 5 μM Pb(C₂H₃O₂)₂·3H₂O), in addition to the observed genotoxicity. During the promotion phase, clonal selection of the transformed cells was clearly observed, as evidenced by an increase in oxidative stress markers, induction of the antioxidant response, and loss of cell viability. Cells with various advantages survived, such as those with a high antioxidant capacity until foci formation.