Table 5.

Alterations in the male reproductive system caused by TiO₂ NPs.

Administration/Dose/Species/Size of NPs	Changes	References
Per os 100 mg/kg/day; 8 weeks Wistar albino rats not specified	- Reduced weight of the testes and epididymides - Decreased sperm count and motility - Reduced levels of testosterone - Deformed and detached heads; curved and coiled tails of spermatozoa - Edema and sloughing of the testicular epithelium, inflammatory cell infiltration - Hyperplasia of the prostate	Azmy et al., 2015 [68]
Per os 0–100 mg/kg/day; 28 days ICR mice not specified	- Decreased motility - Morphological abnormalities of spermatozoa - Reduced activity of SOD - Increased MDA levels	Song et al. 2017 [69]
Intraperitoneal injection 9.38–75 mg/kg/day; 35 days Swiss mice not specified	- Decrease in spermatozoa motility and concentration - Increased number of spermatozoa with morphological damage - Histopathological changes in testicular	Ogunsuyi et al., 2020 [72]
Intragastric administration 2.5–10 mg/kg/day; 90 days Albino mice not specified	- Accumulation of NPs in the testes - Changes in sex hormone levels - Changes in the expression of genes that are involved in the process of spermatogenesis - Testicular lesions and morphological spermatozoa damage	Gao et al., 2013 [73]