In vitro reproductive toxicity of musk xylene and musk ketone in bulls

Studies investigating the toxic effects of nitro musks on male reproduction system are limited. This study investigates the in vitro reproductive toxicity of musk xylene and musk ketone. Epididymal-testicular complexes from four mature Holstein bulls were transported to the lab at +4 °C and cultured. Semen samples from three bulls were diluted to 1 × 10 6 spermatozoa/ml and subjected to the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. Musk ketone and musk xylene were applied to these samples and testicular cell cultures. After 24 h, toxicity was assessed using MTT and CASA (Computer Assisted Sperm Analysis) for semen analysis. Both musk ketone and musk xylene significantly reduced IC 50 concentration by 77.31 % and 55.83 %, respectively. IC 50/2 concentration dropped by 56.92 % for musk ketone and 48.30 % for musk xylene compared to the group without musk compounds. Total motility showed significant differences, with musk ketone reducing sperm motility by 5.68 % more than musk xylene. Velocity parameters, including curvilinear path (VCL), straight-line path (VSL), and velosity average path (VAP), differed significantly between the control and other dose groups. Musk ketone decreased VCL, musk xylene decreased VSL, and both substances reduced VAP values compared to the control. Flow cytometry evaluated acrosome integrity and viability. No significant differences were found in flow cytometry parameters. This study emphasizes that these findings are solely in vitro; further validation through in vivo studies is crucial. A comprehensive understanding of these compounds' impact on reproductive health requires exploring their toxicokinetic properties and interactions with other pollutants via genomic, proteomic, and metabolomic studies. • Both musk ketone and musk xylene significantly reduced IC 50 concentration by 77.31 % and 55.83 %, respectively. • Musk ketone and musk xylene are toxic to bull sperm, drugs impair some sperm functions, and MK has a higher toxicological effect than MX in many parameters. • In male reprotoxicity studies, the CASA system, MTT and Flow Cytometry can be used together as a battery test.