Herbicides Mixture with Potent Endocrine-Disrupting Properties In Goldfish: As An Early Warning At Environmentally Relevant Concentration

For a meaningful interpretation of sub-lethal effect on fish, we have conducted a series of studies with a relevant environmental concentration of a mixture of herbicides; Atrazine, simazine, diuron and isoproturon (ASDI) to observe endocrine-disruption in goldfish under controlled laboratory conditions. Carassius auratus were exposed to 50µg/l of ASDI mixture for 12 weeks. Recorded mid-term assays shows, significant increased levels of cortisol and aromatase after 4-weeks. Reduction in aromatase activity at 8 and 12 weeks is followed by estradiol (E2) showing a positive correlation between them. Hence, 11-Keto reduced significantly at 4-8 weeks and enhanced at 12 weeks. Remarkable reduction in E2 and 11-Keto may be correlated with the reduced egg production in stressed fish by these herbicides. However, no remarkable change in testosterone is observed at 4 and 12 weeks as compared to the control. ASDI mixture treatment induced remarkable induction in vitellogenin (Vtg) biomarker protein in male stressed fish. Furthermore, it may confer that modulation in the pathway of the reproductive cycle may alter the gamete quality, quantity and consequently may disrupt spawning and mating behaviour in fishes even at a realistic level of pollutant in the environment.