GSH, H2O2 production, and lipid peroxidation levels in testes and sperm following 21 consecutive days of 2,5-HD treatment in rats. Each bar represents mean ± SD of eight rats. aP < 0.05 vs. Control; bP < 0.05 vs. 0.25% 2,5-HD, cP < 0.05 vs. 0.5% 2,5-HD.