Many products contain silver nanoparticles, which are adsorbed by living organisms and then go through biological barriers. In particular, penetration of silver nanoparticles through the placental barrier is likely to damage the offspring. Here, we review hazards of silver nanoparticles with focus on exposure during pregnancy, toxicokinetics at maternal and fetal layers, ex vivo and in vivo placenta transfer models, and factors affecting the transfer. Exposure occurs by oral uptake, inhalation, dermal contact, and systemic administration. Toxicokinetics include absorption, distribution in tissues, metabolism and excretion. The accumulation efficiency is primarily influenced by the mode of exposure. Injection exhibits the highest bioavailability, followed by inhalation and oral uptake. Particles within the range of tens of nanometers are capable of crossing the placenta, according to an ex vivo placental perfusion model. In contrast, larger particles in the range of hundreds of nanometers are expelled outside. Due to the size restriction of the trophoblast channel, which typically ranges from 15 to 25 nm, it is possible for silver nanoparticles with an average size of around 20 nm to passively enter the placenta through the pericellular pathway, such as diffusion. On the other hand, larger silver nanoparticles may be delivered to the placenta through endocytosis, which can occur via phagocytosis, receptor-mediated or independent mechanisms.

许多产品含有银纳米颗粒，它们被活体吸附，然后穿过生物屏障。特别是，银纳米颗粒穿过胎盘屏障可能会损害后代。在这里，我们回顾了银纳米粒子的危害，重点是妊娠期间的暴露、母体和胎儿层的毒代动力学、离体和体内胎盘移植模型以及影响移植的因素。通过口服、吸入、皮肤接触和全身给药而发生暴露。毒代动力学包括吸收、组织分布、代谢和排泄。积累效率主要受暴露模式的影响。注射剂的生物利用度最高，其次是吸入和口服。根据离体胎盘灌注模型，数十纳米范围内的颗粒能够穿过胎盘。相比之下，数百纳米范围内的较大颗粒被排出体外。由于滋养层通道的尺寸限制（通常范围为 15 至 25 nm），平均尺寸约为 20 nm 的银纳米粒子有可能通过细胞周途径（例如扩散）被动进入胎盘。另一方面，较大的银纳米颗粒可以通过胞吞作用递送至胎盘，胞吞作用可以通过吞噬作用、受体介导的或独立的机制发生。