Phthalates, including dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), are widely
used plasticizers associated with male reproductive toxicity. This study evaluated the dose- and
temporal-dependent effects of DBP and DEHP (100, 200, and 400 mg/kg for 15 days) on testicular
structure and function in immature Swiss albino mice at 36, 45, 50, and 70 days of age. Biochemical
analyses revealed significant glutathione depletion accompanied by increased nitric oxide and lipid
peroxidation levels, suggesting oxidative imbalance. Histological evaluation demonstrated severe
dose-dependent testicular injury, particularly at 36–45 days, with the 400 mg/kg groups showing 100%
damaged seminiferous tubules and marked reductions in Johnsen’s scores (3.5 ± 0.17 vs. 9.9 ± 0.10 in
controls). Increased Caspase-3 and NF-κB expression suggested possible involvement of apoptotic
and inflammatory responses. Longitudinal assessment from 50 to 70 days revealed a dose-dependent
recovery pattern, with substantial restoration in lower-dose groups, whereas higher doses remained
associated with persistent tubular damage at 70 days (47.0% in DBP and 58.8% in DEHP groups).
These findings suggest that the severity of testicular injury and the extent of recovery are influenced
by phthalate exposure dose. Therefore, further studies are required to fully understand the underlying
molecular mechanisms.