Comprehensive Review on the Toxicology of Neodymium Oxide and Pharmaceutical Applications

Neodymium oxide (Nd₂O₃) particles, which are widely used as a material additive, have attracted significant attention because of their potential toxic effects. Although numerous studies have examined Nd₂O₃ toxicity in humans, a comprehensive review remains unavailable. This is the first review to summarize and discuss the findings of toxicity studies on Nd₂O₃ and its application in pharmaceutics. Specifically, we review the industrial applications of Nd₂O₃ and the in vivo and in vitro studies on its cytotoxicity, respiratory toxicity, neurotoxicity, embryotoxicity, and pharmaceutical application. Nd₂O₃ promotes inflammatory factor production in cells. It causes lung tissue injury by increasing inflammatory and oxidative stress indices. It also reduces the learning ability and memory of children by altering neurotransmitters and increasing oxidative stress indices. Furthermore, it increases embryonic mortality and the malformation rate of embryos through the activation of apoptotic pathways. This review highlights the shortcomings of current research and provides direction for future research on the toxicity and the safe and reasonable application of Nd₂O₃. This review may help people fully understand the toxicity of and safety precautions in using Nd₂O₃.