Detection and Analysis of Microplastics in Human Sputum

Area of Science:

• Environmental Science
• Toxicology
• Human Physiology

Background:

• Microplastic pollution is a growing global concern with limited research on human health impacts.
• Understanding microplastic presence in the human body is crucial for assessing exposure risks.

Purpose of the Study:

• To investigate the presence of microplastics in human sputum.
• To determine if humans involuntarily inhale microplastics.
• To identify types and sizes of microplastics in the respiratory tract.

Main Methods:

• Retrospective case series involving 22 patients with respiratory diseases.
• Sputum sample collection and analysis using Agilent 8700 laser infrared imaging spectrometer and Fourier-transform infrared microscope.
• Detection of microplastics in the size range of 20-500 μm.

Main Results:

• Microplastics were detected in all analyzed sputum samples, indicating ubiquitous presence.
• 21 types of microplastics were identified, with polyurethane, polyester, chlorinated polyethylene, and alkyd varnish being dominant.
• Detected microplastics were predominantly smaller than 500 μm (median size: 75.43 μm).
• Microplastic quantities correlated with factors like smoking and invasive examinations (P < 0.05).

Conclusions:

• Inhalation is a significant pathway for microplastics entering the human body.
• Findings provide foundational data for human health risk assessments related to microplastic exposure.
• This study underscores the need for further research into the health implications of inhaled microplastics.