Toxicity assessment of SiO ₂ nanoparticles on developmental and reproductive traits in <i>Drosophila melanogaster</i>

Silicon dioxide nanoparticles (SiO₂ NPs) are widely utilized in industrial and biomedical applications owing to their unique physicochemical properties; however, their potential biological effects require comprehensive evaluation. In this study, the model organism <i>Drosophila melanogaster</i> was employed to investigate the impacts of dietary exposure to SiO₂ NPs of different sizes and concentrations on developmental and reproductive outcomes. The assessed parameters included egg-laying rate, pupation time, adult emergence time, pupation rate, adult emergence rate, larval weight, and sex ratio. The results revealed that at concentrations of 0.2% or lower, neither nanoparticle size produced significant effects on development or reproductive capacity. In contrast, exposure to 2% SiO₂ NPs (both 15 nm and 30 nm) led to reduced body weight in third instar larvae. Notably, 30 nm SiO₂ NPs exposure significantly decreased pupation and adult emergence rates and was associated with delayed pupation and emergence times. Although total egg production remained unchanged, flies exposed to 30 nm SiO₂ NPs exhibited an earlier oviposition peak. These findings suggest that exposure to SiO₂ NPs at the national standard concentration of 0.2% does not cause notable developmental effects in <i>Drosophila</i>, whereas a tenfold increase in concentration may induce developmental delays. Considering that the 0.2% standard is based on human exposure and accounting for interspecies extrapolation, the 2% concentration may still represent a relevant dose range. Overall, these results indicate that excessive intake of SiO₂ NPs could pose toxicological risks and provide a theoretical foundation for further studies on the mechanisms underlying SiO₂ NPs-induced toxicity.