Do the azo food colorings carmoisine and ponceau 4R have a genotoxic potential?

Today, ready-to-eat foods to which various additives are frequently added are widely consumed. Food colorings constitute an essential part of these additives. Carmoisine (E-122) and Ponceau 4R (E-124) are the most commonly used azo food colorings. This study aimed to investigate the in vitro genotoxic effects of these two food dyes in human peripheral lymphocytes using four different and complementary genotoxicity tests (chromosome aberrations (CAs), sister chromatid exchange (SCEs), cytokinesis block micronucleus cytome (CBMN-Cyt) and comet). When four different concentrations (37.5, 75, 150, and 300 μg/mL) of both food dyes were applied to lymphocytes for 24 and 48 h, it was observed that only the highest concentration significantly increased the frequencies of CA and SCE. The mitotic index (MI) decreased compared to the control at all concentrations except the lowest one in the 24-h treatment of Carmoisine and the two highest concentrations (150, 300 μg/mL) in the 48-h treatment. In the 24-h Ponceau 4R treatment, MI decreased compared to the control at all concentrations except the lowest and all concentrations in the 48-h treatment. In contrast, Carmoisine and Ponceau 4R did not affect MN frequency. In the comet test, Carmoisine increased tail length only at the highest concentration, and Ponceau 4R increased tail length at the two highest concentrations. Ponceau 4R also increased tail moment only at the highest concentration. When the results of these four in vitro genotoxicity tests were evaluated together, it was concluded that both food colors were genotoxic, especially at high concentrations, but not at low concentrations.