Microplastics and Nanoplastics in Atheromas

Microplastics and Nanoplastics in AtheromasTo the Editor: Marfella et al. (March 7 issue) 1 found the presence of microplastics and nanoplastics (MNPs) in carotid artery plaque and linked it with a higher risk of cardiovascular events.However, many factors suggest potential external plastic contamination of samples collected in this study. 2First, no pre-analytical anticontamination procedures were implemented (only the use of glass tubes is mentioned), so credible detection of MNPs may be questioned.The surgical environment and equipment contain many MNPs, including polyethylene and polyvinyl chloride, and the risk of contamination with MNP intraoperatively is very high. 3Also, no blank samples from the operating room were tested. 4 The sizes of the MNPs that were detected in this study were considerably smaller than those detected in previous studies (<1 m vs. 3 to 469 m). 2,3 MNPs in samples should also be detected by means of several complementary methods, whereas only gas chromatography-mass spectrometry was used for all plaques, and scanning electron microscopy with stable isotope analysis was used only for selected MNP-positive samples for confirmation, a protocol that may have introduced bias. 5 Without addressing these key methodologic issues, the results of this study may not be fully reliable.