For the present study, azo dye tartrazine (acid yellow 23) having wide range of application in textiles and synthetic foods, was used to assess the toxic effects and biomarker responses in fish Labeo rohita (Hamilton, 1822), commonly known as rohu. In toxicity studies haematological estimation is recognized as significant before many years. Acute (T1, T2 and T3 for 96 hours) and chronic (CT1 and CT2 for 75 days) bioassays were conducted. Major physico-chemical characteristics of aquaria water were analysed and recorded in regular intervals of experiment. After the experimental period, blood was collected and major haematological parameters; Hb, TC, RBC, PCV, MCV, MCH and MCHC were analysed. The results show that parameters Hb, RBC, PCV, MCV, MCH were significantly reduced and TC was significantly increased in highest concentration of acute test (T3) and in chronic tests (CT1 and CT2). The changes in haematological parameters can reflect the physiological status of animal and indicates the environmental conditions where they being. The experimental study establishes that haematological indices such as Hb, TC, RBC, PCV, MCV, and MCH are good biomarkers of the tartrazine exposure in fishes..

Background: Synthetic azo dyes are very extensively using various industries such as food items and non-food items. Tartrazine is well known azo dye due to its wide range of applications, also known as acid yellow 23. Most industries release these dyes containing effluents into water bodies without proper treatment. There is no well-documented study about the toxicological effect of tartrazine in fishes. Most studies with tartrazine are concentrated in humans and rats. However, there is a high chance of reaching the dye in natural water bodies either through direct or indirect deposition and there is a necessity of understanding its effects on fish. Objective: The study was conducted to assess the effect of synthetic azo dye tartrazine on fishes due to long-term exposure. Materials and Methods: Labeo rohita commonly known as Indian major carp was selected as experimental fish and the major parameters discussed are the growth of the fish in terms of condition factors and the biochemical changes in the brain. Experimental fishes were grouped after the acclimatization of seven days as control (C), test 1 (T1), and test (T3). The major biochemical parameters analyzed include total proteins, carbohydrates, lipids, free amino acids; antiperoxidative enzymes-GST, GR, GPx, SOD, CAT; lipid peroxidation product MDA and activity of AChE. After the chronic exposure experiment of 75 days, the control and test fishes were subjected to morphometric measurements and biochemical analysis. Results:The results show that the weight of experimental fishes reduced significantly (P<.001) with respect to control groups. Antiperoxidative enzymes were also altered in the experimental fishes with respect to control. AChE activity also decreased significantly. Lipid peroxidation product MDA increased in the brain tissues of the experimental fishes. Conclusion:The study concluded that tartrazine has detrimental effects on the fish by altering the biochemical as well as physiological attributes.