The dyeing of fabrics began thousands of years ago and the commercial availability of dyes is enormous and growing. The Brazilian textile industry plays a very important role, among the main economic activities of the country. However, the inefficiency in dyeing process, mainly during the dye fixation step, results in large amounts of dyes (2-50%) directly released in the effluents, affecting the aquatic environment. The molecule of the dyes is classified into two main parts, the chromophore group, responsible for the color and the group responsible for attaching to the fiber. Our group has demonstrated that the textile dye, Disperse Red 1 (DR1) is an azo dye which induces genotoxicity/mutagenicity in HepG2 cells and Salmonella typhimurium and it is very toxic to Daphnia similis. Additionally, preliminary results also performed by our group showed that Reactive Orange 16 (RO16) dye significantly inhibited the ability of zebrafish (Danio rerio) embryos to hatch, while Direct Black 38 (DB38) presented failures in gas bladder inflation. In this context, this project proposes to evaluate the toxicity of the DB38, DR1 and RO16 dyes on embryonic and larval development, as well as on the DNA of zebrafish. For this purpose, the test toxicity with the early stages of development of zebrafish, known as the Early Life Stage (ELS) Toxicity Test will be used. Thus we will perform analysis of toxicological indicators of lethality, sub-lethality and teratogenicity, as well as the Comet assay to investigate the genotoxicity of dyes on the larvae of this test organisms. The results of this study will provide valuable information in order to avoid damage to the environment and human health, besides enabling the application of this test (ELS) as a standard method to assess the potential toxicity of other textile dyes and effluents, ensuring use of safer compounds for dyeing textile industries. Moreover, the implementation of this model in the Laboratory of Environmental Toxicology of FCFRP / USP is a national innovation, considering that the ELS test is not being conducted in Brazil.
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