Inhalation as a PFAS Exposure Route
While drinking water and diet are the primary PFAS exposure routes for most people, inhalation is significant in occupational settings and indoor environments. PFAS volatilize from treated fabrics, carpets, and food packaging, contributing to indoor air contamination. Workers in PFAS manufacturing, semiconductor fabrication, and textile coating industries face substantial inhalation exposures.
Inhalation bypasses gastrointestinal absorption and delivers PFAS directly to lung tissue and the systemic circulation via pulmonary capillaries. Alveolar macrophages — the lung’s immune sentinels — accumulate PFAS and may sustain chronic low-grade pulmonary inflammation.
Lung Function and Asthma Research
Cross-sectional studies using spirometry data from NHANES have found associations between higher PFAS serum levels and reduced FEV1 (forced expiratory volume) and FVC (forced vital capacity) — key indicators of lung function. These reductions were modest but statistically significant, suggesting subclinical airway restriction.
Children with higher prenatal PFAS exposure show increased rates of wheezing, asthma diagnosis, and atopic sensitization. Proposed mechanisms include PFAS-induced Th2 immune skewing that promotes allergic airway inflammation and PFAS effects on surfactant production that affect airway compliance.
Occupational and Indoor Air Protection
Workers in high-exposure occupations should be provided respiratory protection and undergo periodic pulmonary function testing. Industrial hygiene measures to minimize airborne PFAS in workplaces are required by occupational health regulations in many jurisdictions.
For residential environments, improving ventilation, using PFAS-free products, and replacing older PFAS-treated carpets and upholstery reduces indoor air exposure. Air purifiers with activated carbon filters can capture some volatile PFAS compounds, though their effectiveness varies by compound and air exchange rate.