Non-destructive extraction and characterization of human pulmonary microplastics and the associated endocrine...

Inhalation exposure to microplastics (MPs) and associated plastic additives has raised growing public health concerns, although their distribution and potential health impacts in human lungs remain poorly understood. To minimize interference from lipids and collagen fibers, particulate matter (PM) was first extracted from lung tissues using a non-destructive ultrasonic treatment and sequential centrifugation (USC) method, followed by obtaining the microplastic extract (MPE) using ultrasound and density separation (UDS), and subsequent detection of EDCs via GC-MS. This approach enabled characterization of both pulmonary MPs and associated EDCs. Sixteen polymer types were identified, with nylon (27.3%), polyester (10.7%), and polyurethane (7.8%) being the most abundant, alongside 71 EDCs, including phthalic acid esters (PAEs), organophosphate esters (OPEs), and polycyclic aromatic hydrocarbons (PAHs). Smokers and individuals over 60 years old showed significantly higher pulmonary MP abundances (P < 0.01). EDC concentrations were higher in MPE than in surrounding lung tissues, particularly for PAEs, which showed elevated enrichment factor MPs (EFMs range: 16.4-101; mean: 50.1). The average concentration of pulmonary MPs, estimated via PAEs under an upper-bound scenario, was 7.35 mg/kg. The heterogeneous distribution of MPs and additives within pulmonary tissues may have implications for localized exposure, although the biological effects remain to be further investigated. These findings underscore the importance of characterizing MPs and associated contaminants to better assess potential health risks.