The continuous accumulation of micro- and nanoplastics in the human living environment and their deposition in various organs of the body have become a global public health concern with the widespread use of plastic products. This review summarizes the main categories of micro- and nanoplastics entering the body through dietary intake and air inhalation, based on human exposure pathways. By integrating existing literature data, this review estimates the daily intake and excretion of micro- and nanoplastics in humans, summarizes evidence regarding their potential deposition patterns in blood cells and hematopoietic-related organs, mainly inferred from animal and in vitro studies, and discusses the possible impacts of such deposition on hematopoietic function. Furthermore, the toxic effects and potential hazards of micro- and nanoplastics on the human hematopoietic system at both cellular and animal levels, along with the underlying molecular mechanisms, are comprehensively reviewed. From the dual perspectives of environmental governance and bodily protection, exploratory research ideas are proposed, including biodegradation strategies and the application of medicinal and edible homologous substances. This review aims to provide insights for reducing the risk of hematopoietic system diseases and preventing harm caused by micro- and nanoplastics to the human body in the future.

Background: Pneumonia poses a significant health threat and adversely affects the well-being and recovery of patients, particularly the elderly. With the growing emphasis on preventive healthcare and the rise in population aging, the prevention of pneumonia has become increasingly crucial. Povidone-iodine, a readily available and potent bactericidal disinfectant, has garnered attention for its potential in preventing pneumonia through oral disinfection. Objective: To evaluate the preventive effect of povidone-iodine on pneumonia. Methods: This article systematically searched for published studies in English and Chinese database between 2004 and 2024. This study included studies reporting the clinical application and effect of povidone iodine and the incidence of pneumonia. The raw data from these studies were pooled into the analysis of this article. The statistical analyses used in this study were performed using Stata version 17.0 (Stata Corp LLC, College Station, TX). Results: Fifteen studies were included in the study analysis. Nine studies showed that povidone-iodine reduced the incidence of pneumonia compared with saline, placebo, and oral care . The remaining 4 articles all showed the positive effect of povidone-iodine on the prevention of pneumonia. Two other studies showed that chlorhexidine oral care was more effective than povidone-iodine in preventing pneumonia, but only one study was statistically significant. Conclusion: The use of povidone iodine for gargling, mouth and nose care is a protective factor against pneumonia. It has important implications for pneumonia prevention strategies.