Titanium dioxide (TiO2) nanoparticles are among the most manufactured nanomaterials in the industry, and are used in food products, toothpastes, cosmetics and paints. Pregnant women as well as their conceptuses may be exposed to TiO2 nanoparticles; however, the potential effects of these nanoparticles during pregnancy are controversial, and their internal distribution has not been investigated. Therefore, in this study, we investigated the potential effects of oral exposure to TiO2 nanoparticles and their distribution during pregnancy. TiO2 nanoparticles were orally administered to pregnant Sprague-Dawley rats (12 females per group) from gestation days (GDs) 6 to 19 at dosage levels of 0, 100, 300 and 1000 mg/kg/day, and then cesarean sections were conducted on GD 20. In the maternal and embryo-fetal examinations, there were no marked toxicities in terms of general clinical signs, body weight, food consumption, organ weights, macroscopic findings, cesarean section parameters and fetal morphological examinations. In the distribution analysis, titanium contents were increased in the maternal liver, maternal brain and placenta after exposure to high doses of TiO2 nanoparticles. Oral exposure to TiO2 during pregnancy increased the titanium concentrations in the maternal liver, maternal brain and placenta, but these levels did not induce marked toxicities in maternal animals or affect embryo-fetal development. These results could be used to evaluate the human risk assessment of TiO2 nanoparticle oral exposure during pregnancy, and additional comprehensive toxicity studies are deemed necessary considering the possibility of complex exposure scenarios and the various sizes of TiO2 nanoparticles.

中文翻译：

---

二氧化钛纳米颗粒经口暴露于孕鼠及其分布

二氧化钛（TiO2）纳米粒子是该行业中制造最广泛的纳米材料之一，并用于食品，牙膏，化妆品和油漆中。孕妇及其概念可能会暴露于TiO2纳米颗粒中。然而，这些纳米粒子在怀孕期间的潜在影响尚存争议，尚未对其内部分布进行研究。因此，在这项研究中，我们调查了口服TiO2纳米颗粒的潜在影响及其在怀孕期间的分布。从妊娠天（GDs）6至19口服给予怀孕的Sprague-Dawley大鼠（每组12只雌性）TiO2纳米颗粒，剂量水平为0、100、300和1000 mg / kg / day，然后进行剖宫产。 GD20。在孕产妇和胚胎胎儿检查中，在一般临床体征，体重，食物消耗，器官重量，肉眼所见，剖宫产参数和胎儿形态学检查方面，没有明显的毒性。在分布分析中，暴露于高剂量的TiO2纳米颗粒后，母体肝脏，母体脑和胎盘中的钛含量增加。孕妇在口服期间接触TiO2会增加母体肝脏，母体脑和胎盘中的钛含量，但这些含量不会对母体动物产生明显的毒性或影响胚胎胎儿的发育。这些结果可用于评估怀孕期间TiO2纳米颗粒口腔暴露的人类风险评估，