"Brazil is the third largest world producer of candies and chewing gums, with a market of more than 3 billion dollars. This expressive amount of candy dealt each year involves an even more expressive volume of wastewater. Dyes are usually added in the formulation of such products to increase attractiveness, acceptability and esthetic appearance of the product ... However, the use of some of these additives is still a complex and controversial issue." (Quoted from paper)