Genotoxic effects of titanium dioxide (TiO2) to adult Labidochromis caeruleus (fryer, 1956) type: Micronucleus test

Objective: In this study it was aimed to investigate the possible genotoxic effects of titanium dioxide (TiO2) nanoparticles on Labidochromis caeruleus (Fryer, 1956), which is one of the most used fish species in laboratory research, by micronucleus test. Material and Methods: Adult individuals of L. caeruleus, consisting of 28 males and 27 females, were treated with TiO2 at concentrations of 25 mg/L, 50 mg/L and 100 mg/L for 24 hour, 48 hour and 96 hour periods. Rested water was used in the negative control and 5 mg/L EMS (Ethyl Methane Sulphonate) was used in the positive control. At the end of the application periods preparats were prepared with samples taken from gill and tail blood. In microscopic examination, a total of 6000 cells per fish were counted, 3000 for each of the gill and tail samples. The data obtained were analyzed in the SPSS Statistics-22 statistical program and compared. Results: As a result of micronuclei (MN) frequency analysis; It was determined that MN frequencies increased in all experimental groups compared to the negative control group, but this increase was not significant in all groups. It was determined that MN frequencies of tail samples were higher than gill samples. According to the analysis of morphological nucleus irregularities; According to the analysis of morphological nucleus irregularities; binucleus, notched nucleus, budded nucleus and lobed nucleus frequencies increased in all gill and tail samples compared to the negative control group. It was determined that the total genotoxic damage frequencies increased significantly in all groups compared to the negative control group. Conclusion: It was determined that the concentration-time interaction was statistically significant in terms of MN frequencies in the experimental groups treated with TiO2, and the increase in the application time caused an increase in the MN frequencies. Key Words: Labidochromis caeruleus, Micronucleus, Morphological Nucleus Irregularities, Nanoparticle, Titanium dioxide.