Figure 5: Effects of the metal mixture (2  M NaAsO2, 2  M CdCl2, and 5  M Pb(C2H3O2)2·3H2O) through promotion phase of transformation process, antioxidant activity markers. Balb/c 3T3 cells were exposed 4 hours to initiator stimuli, metal mixture or MNNG (positive initiator), on day 1 and promoter stimuli, metal mixture or TPA (positive promoter), on days 7, 11, and 14. Samplings were on days 11, 16, and 21 of the transformation protocol for monitoring promotion phase. Data represent the mean of 3 individual experiments performed by triplicate. Antioxidant activity is represented as a percentage with respect to control values. Superoxide dismutase (SOD) and catalase activities were evaluated using spectrophotometric assays, and the total antioxidant capacity (TAC) was assessed by the ABTS° + radical method (ANOVA and Student’s t-test; * , ** , *** versus control bars).