Shipping can be achieved but cargo arrives with damage-titanium dioxide nanoparticles affect the DNA of Pacific oyster sperm

Titanium dioxide nanoparticles (TiO2 NP) were reported to be reprotoxic in humans and fish. However, the effects of these NP on the reproduction of marine bivalves, namely oysters, remain unknown. Thus, a short-term (1 h) direct exposure of sperm of the Pacific oyster (Crassostrea gigas) to two TiO2 NP concentrations (1 and 10 mg.L-1) was performed, and sperm motility, antioxidant responses, and DNA integrity were evaluated. Although no changes occurred in sperm motility and the activities of the antioxidants, the genetic damage indicator increased at both concentrations, demonstrating that TiO2 NP affects the DNA integrity of oyster sperm. Although DNA transfer can happen, it does not fulfill its biological mission since the transferred DNA is not intact and may compromise the reproduction and recruitment of the oysters. This vulnerability of C. gigas sperm towards TiO2 NP highlights the importance of studying the effects of NPs exposure to broadcast spawners.

Automated summary

Studies have shown that titanium dioxide nanoparticles (TiO2 NP) have reproductive toxicity to humans and fish, but their effects on marine bivalves, specifically oysters, are still unknown. In this study, Pacific oyster sperm was directly exposed to two concentrations of TiO2 NP (1 and 10 mg/L) for a short term (1 h), and sperm motility, antioxidant responses, and DNA integrity were assessed. Although no changes were observed in sperm motility and antioxidant activities, the indicator of genetic damage increased at both concentrations, indicating that TiO2 NP affects the DNA integrity of oyster sperm. This vulnerability of Pacific oyster sperm to TiO2 NP highlights the importance of studying the effects of NP exposure on broadcast spawners.