Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, is a new technology offering design freedom to create complex structures that has found increasing applications in industrial processes. However, due to the fine metal powders and high temperatures involved, the printing process is likely to generate particulate matter (PM) that has a detrimental impact on the environment and human health. Therefore, comprehensive assessement of the exposure and health hazards of PM pollution related to this technique is urgently required. This review provides general knowledge of metal AM and its possible particle release. The health issues of metal PM are described considering the exposure routes, adverse human health outcomes and influencing factors. Methods of evaluating PM exposure and risk assessment techniques are also summarized. Lastly, future research needs are suggested. The information and knowledge presented in this review will contribute to the understanding, assessment, and control of possible risks in metal AM and benefit the wider metal 3D printing community, which includes machine operators, consumers, R&D scientists, and policymakers.

金属增材制造（AM），也称为金属三维（3D）打印，是一种提供自由设计以创建复杂结构的新技术，这种结构在工业过程中的应用日益广泛。但是，由于金属细粉和高温的影响，印刷过程中可能会产生颗粒物（PM），对环境和人类健康产生不利影响。因此，迫切需要对与该技术有关的PM污染的暴露和健康危害进行综合评估。这篇综述提供了金属AM及其可能释放的颗粒的常识。描述了金属PM的健康问题，并考虑了其暴露途径，不利于人类健康的结果和影响因素。还总结了评估PM暴露的方法和风险评估技术。最后，提出了未来的研究需求。本文中介绍的信息和知识将有助于理解，评估和控制金属增材制造中的潜在风险，并使整个金属3D打印社区受益，其中包括机器操作员，消费者，研发科学家和政策制定者。