Detection of Various Microplastics in Patients Undergoing Cardiac Surgery

Few studiesfocus on microplastic exposure to the organsthat do not have contact with the external environment. This studyreports microplastics within the human heart and its surrounding tissuesand the change of microplastics before and after cardiac surgery. Microplastics have been detected in human stool, lungs,and placentas,which have direct exposure to the external environment through variousbody cavities, including the oral/anal cavity and uterine/vaginalcavity. Crucial data on microplastic exposure in completely enclosedhuman organs are still lacking. Herein, we used a laser direct infraredchemical imaging system and scanning electron microscopy to investigatewhether microplastics exist in the human heart and its surroundingtissues. Microplastic specimens were collected from 15 cardiac surgerypatients, including 6 pericardia, 6 epicardial adipose tissues, 11pericardial adipose tissues, 3 myocardia, 5 left atrial appendages,and 7 pairs of pre- and postoperative venous blood samples. Microplasticswere not universally present in all tissue samples, but nine typeswere found across five types of tissue with the largest measuring469 & mu;m in diameter. Nine types of microplastics were also detectedin pre- and postoperative blood samples with a maximum diameter of184 & mu;m, and the type and diameter distribution of microplasticsin the blood showed alterations following the surgical procedure.Moreover, the presence of poly(methyl methacrylate) in the left atrialappendage, epicardial adipose tissue, and pericardial adipose tissuecannot be attributed to accidental exposure during surgery, providingdirect evidence of microplastics in patients undergoing cardiac surgery.Further research is needed to examine the impact of surgery on microplasticintroduction and the potential effects of microplastics in internalorgans on human health.