Addressing the intersection of COVID-19 and metal nanoparticle use: Risks and control strategies

The outbreak of the novel coronavirus lasted from 2019 into 2023 and the number of patients infected with the virus is still on the rise, greatly impacting people’s daily lives and the environment. Research on metal nanoparticles has developed rapidly during virus outbreaks. There have been review articles summarizing the important role of nanomaterials in the prevention, diagnosis, and treatment of viruses, because they have antimicrobial properties or can be used as drug carriers. However, the widespread application of metal nanoparticles is not yet mature, and there are many cases of abuse, which inevitably produce health and environmental risks. The aim of this review is to highlight the potential health and environmental risks of metal nanoparticles under the COVID-19 pandemic, to propose corresponding strategies to address them, and to point out promising research directions in future. Some metal nanoparticles exposed to organisms and the environment may incur bioaccumulation effects and direct toxicity. Toxicity can be reduced by changing the surface properties of metal nanoparticles, and the accumulation of metal nanoparticles in plants can be used for recycling and regeneration. More importantly, those papers related to life cycle assessment of metal nanoparticles tend to ignore their synthesis and regeneration processes. This paper believes that the production process of metal nanoparticles has a large environmental risk while the end-of-life process is often neglected. We conclude that the synthetic method can be optimized from the green synthesis of metal nanoparticles. Furthermore, additional attention can be paid to the recovery and regeneration of metal nanoparticles to promote the green use of metal nanoparticles and finally reduce pressure on the environment.