Factors affecting micro(nano)plastic release during intravenous therapy: Direct blood exposure.

Intravenous therapy could introduce micro(nano)plastics (MNPs) directly into the human blood, yet factors affecting their release remain poorly understood. This study systematically evaluates critical factors affecting MNP release from medical infusion products (MIPs) during intravenous therapy. Results showed that organic infusion solutions (e.g. glucose) induced 6.47 times higher of MNP release than that of distilled water, and MNP mass increased to 2.02 times with infusion volumes rising from 500 mL to 2000 mL. These results suggested that standard practice using only 500 mL distilled water for MIP quality assessment is inadequate, and necessitates the utilization of actual infusion solutions with larger volumes. A lower infusion rate (20 drops/min) and prolonged MIP storage period (>6 months) significantly increased MNP release into the human blood, thereby rising health risks, particularly for the elderly and children. Interestingly, these factors primarily influenced polyvinyl chloride MNP release, indicating that replacing them with safer alternatives is thus recommended for clinical use. Overall, these observations are promising for ensuring the safe use of MIPs and evaluating the potential health impacts of MNPs.