Impact of perfluorooctanoic acid on sperm function and early development in <i>Prochilodus magdalenae</i> : implications for aquatic species reproduction

Given the well-documented capacity of perfluorooctanoic acid (PFOA) to induce endocrine alterations, this study aimed to investigate the toxicity of PFOA on sperm kinetics and larval viability of Prochilodus magdalenae (bocachico), Colombia's most economically significant freshwater fish species. Gametes were obtained through hormonal induction of P. magdalenae broodstock, and in vitro fertilization was performed to obtain larvae. The semen was activated either with water or water containing different PFOA concentrations (10-500 µM). Sperm motility (both total and specific types), progressivity, and velocity (linear and curvilinear) were assessed using a computer-assisted sperm analysis system. Fertility and hatching were evaluated in two separate experiments: the first involved 1-hr PFOA (10-500 µM) exposure, whereas the second exposure occurred under 12-hr long assays, involving the entire embryonic development, evaluating various morphometric and functional parameters. Bocachico larvae were exposed to different PFOA concentrations for 24 hr to determine the lethality percentage and the median lethal concentration. Sperm motility, progressivity, and velocity were not significantly affected at PFOA concentrations below 200 µM. However, concentrations of 300 µM or higher significantly (p < 0.05) affected sperm kinetics, particularly linear velocity, with a statistical reduction at 500 µM (16.8 ± 6.7 µm/s) compared with the control (54.9 ± 17.9 µm/s). Fertility decline was observed at 1-hr exposure to PFOA concentrations ≥ 300 µM. In contrast, 12-hr exposure to 10 and 50 µM PFOA resulted in significant differences in oocyte diameter, yolk sac area, and heart rate compared with the control. The results showed that PFOA exposure causes harmful effects on the early developmental stages of P. magdalenae, posing a potential risk to fertility and reproductive success in wild populations.