Rapid and efficient method for assessing nanoplastics by an electromagnetic heating pyrolysis mass spectrometry

Nanoplastics are an emerging topic and have attracted increasing attention due to their widespread existence and potential toxicity on living organisms. The challenges of analytical methods for nanoplastics hinder the deeper understanding of toxicological effects and risk assessment of nanoplastics. In this work, a custom-built electromagnetic heating pyrolyzer was coupled to mass spectrometry for the rapid analysis of nanoplastics. Nanoplastics/microplastics were collected on the heat-resisting filter papers, then directly decomposed into gaseous products in the pyrolyzer and analyzed by mass spectrometry. The polystyrene nanoparticles were used to verify the performance of mass-traced quantification, and recoveries of 106-121% and precision of 9% were obtained. As a proof-of-principle experiment, the saline solution packed by polypropylene infusion bottles was aged for simulating indoor sunlight storage, where nanoplastics/microplastics were analyzed. The abundance models of nanoplastics/microplastics in the saline infusion bottle with aging time were assessed from both quality and quantity, for the first time. Results showed that nanoplastics/microplastics in medical infusion products could be generated under indoor sunlight exposure, which needs more attention due to the potential health risks. The proposed electromagnetic heating pyrolysis-mass spectrometry could be a promising method for assessing nanoplastics/microplastics.