Considerations on the toxicity of brilliant blue FCF aqueous solutions before and after ozonation

Abstract

The food dyes have a potential toxic effect on aquatic organisms which trigger the necessity of their removal from industrial or urban wastewaters. Many different removal methods were investigated for this purpose, but the ozonation and advanced oxidation processes (AOPs) were successfully applied in this field. However, the majority of studies emphasized that color removal by ozonation process did not report a complete mineralization of the dye and the resulted by-products may have a greater toxicity than the original compound. In this context, the paper presents a comparative ecotoxicity study of the dye Brilliant Blue FCF (BB FCF) before and after ozone treatment. The BB FCF toxic effect, before and after ozonation was investigated on crustacean (Daphnia magna), lethal or inhibitory concentrations for 50% of tested organisms (LC50 / EC50) were used to estimate the effect level. The dye showed no toxicity on crustacean (CL50/CE50>100mg/L) before ozonation. The ozonized solutions presented a high toxicity for crustaceans compared to initial dye due to the by-products occurrence.