Toxicological effects of food additives azo dyes

BACKGROUND: Azo dyes are widely used in foods, pharmaceuticals and cosmetics. They have been tested in several screenings regarding their effects on human health, but very little data is available on endocrine disrupting effects. The aim of this study has been to screen the effects of four azo dyes in different toxicological assays in the human adrenocortical H295R cell line. These results could be of importance for the evaluation of health effects of azo dyes. METHODS: Using different in vitro models, we have examined the effects of azo dyes on oxidative stress, sex hormone production and gene expression of transport protein. The oxidative stress response was studied using luciferase reporter assay, the sex hormone production was studied with ELISA and gene expression was studied using real-time PCR. Further, we have used MTS assay to investigate the general cytotoxicity induced by azo dyes. Results: This study show that Brilliant Black down regulate the gene expression of the transport protein BCRP in H295R cells and that sunset yellow induces oxidative stress in H295R cells. Conclusion: This project presents a toxicological screening of azo dyes using multiple toxicological endpoints. We conclude that azo dyes can induce oxidative stress response and alter gene expression of transport proteins, in H295R cells. However, further investigation is needed to clarify the toxicity of azo dyes and the mechanisms for these effects.