A job exposure matrix for occupational exposure to airborne micro and nanoplastics (PlastiXJEM®️) and associations with respiratory outcomes

BACKGROUND: Microplastics and nanoplastics (MNP) are an increasingly recognized component of airborne particulate matter, yet their impact on respiratory health is unclear. This study aimed to develop a job exposure matrix (JEM) for occupational exposure to airborne MNP (PlastiXJEM®️ and examine its association with respiratory outcomes in the Lifelines cohort.

METHODS: Four experts scored occupational airborne MNP exposure levels (none, low, high) for all ISCO-08 occupations based on documented sources and published evidence. After consensus, the PlastiXJEM®️ was applied to baseline current or last-held jobs of 136,928 adult Lifelines participants. Cross-sectional and longitudinal associations with lung function, respiratory symptoms, and asthma were assessed using linear and logistic regression models adjusted for age, sex, smoking, height, BMI, and co-exposure to organic dust, gasses and fumes, pesticides, metals, solvents and silica.

RESULTS: High exposure was associated with lower FEV1 (-43 ml; 95% CI:-61;-25), lower FVC (-47 ml (-69;-26)), lower FEV1%FVC (-0.26% (-0.51;-0.00) and higher odds of airway obstruction, respiratory symptoms and asthma (e.g. dyspnea OR = 1.58; 1.34-1.87). Low exposure was associated with lower FEV1 and FVC in females only. Overall, effect sizes were larger at higher exposure levels, consistent with a dose-dependent pattern. MNP exposure was not associated with accelerated lung function decline or with the development of airway obstruction, respiratory symptoms, or asthma.

CONCLUSION: Occupational exposure to airborne MNP is associated with lower lung function and a higher prevalence of respiratory symptoms in this cohort. These findings warrant further investigation with complete occupational histories.