145 Cumulative Occupational Exposure to Nanoparticles, Inflammatory Biomarkers and Respiratory Health in the Nanoexplore Cohort

Exposure to nanomaterials (NMs) may harm biological systems by altering the redox status and triggering inflammatory processes, which in turn may affect respiratory health. In the NanoExplore cohort of 141 workers, we observed a positive dose-response relationship between the short-term exposure to NMs and biomarkers of inflammation, measured in Exhaled Breath Condensate (EBC), but no relationship with lung function parameters (LFP). This study focuses on the association between cumulative exposure to NMs over the last 10 years and changes in LFP and the potential mediating role of airways inflammation. Individual cumulative exposure was estimated by multiplying the nanoparticle concentration, measured at workers’ workstations by DiSCmini, by the duration of worker’s employment at the corresponding workstation up to last 10 years. In EBC, we measured High-Sensitivity CRP (Hs-CRP), IL-1β, TNF-α, and IL-10 as biomarkers of inflammation. LFP were assessed according to ATS/ERS standards. Their association with cumulative exposure was examined using logistic regression models adjusted for tobacco consumption (in pack-years), among 136 workers with complete data (19-62 yrs., 70% males). We found that per unit increase in 10-year exposure, the risk of observing FEV1 values below the normal limit increases by 0.3% (95%CI: 1.000-1.005, p=0.049) and by 0.8% (95%CI: 1.000-1.015, p=0.039) with the exposure expressed as number of particles and lung deposited surface area, respectively. The ongoing mediation analysis will investigate the potential mediating role of inflammation in the association between cumulative exposure to NMs and lung function