The accumulation and tissue distribution of gold nanoparticles exposure in pregnant rats

Abstract

Limited research on the toxicokinetics of nanoparticles (NPs) in pregnant rats hinders our understanding of the potential risks they pose to the pregnant population. This study examined how exposure dose and size of NPs impacted their specific distribution in pregnant rats under repeated dosing. Results revealed that Au NPs mainly accumulated in the spleen and liver, followed by the uterus, while the heart, placenta, and fetus showed the least accumulation. The decrease of exposure size induced faster elimination of Au NPs in serum and organs. The increase of exposure dose induced faster elimination in serum but slower elimination in organs, higher accumulation, and larger size of Au NPs in vivo. The accumulation and biodistribution of Au NPs varied across different organs depending on the exposure size. Particularly, Au NPs with an in vivo size of 40 nm were shown to transfer the placenta and accumulate in the fetus, regardless of the exposure dose and size. Such effect was closely related to the transport routes of Au NPs across the placenta, possibly via vesicular transport and the uptake of trophoblast cells. Our study illustrating the specific distribution of NPs in vivo provides important evidence for assessing the health risk of NPs.