Biomarkers of endothelial activation and thrombosis in tunnel construction workers exposed to airborne contaminants

Objectives: The aims were to study biomarkers of systemic inflammation, platelet/endothelial activation and thrombosis in tunnel construction workers (TCW). Methods: Biomarkers and blood fatty acids were measured in blood of 90 TCW and 50 referents before (baseline) and towards the end (follow-up) of a 12 days work period. They had been absent from work for 9 days at baseline. Air samples were collected by personal sampling. Results: Personal thoracic air samples showed geometric mean (GM) particulate matter and α-quartz concentrations of 604 and 74 µg/m3, respectively. The arithmetic mean (AM) concentration of elemental carbon was 51 µg/m3. The GM (and 95% confidence interval) concentration of the pro-inflammatory cytokine TNF-α decreased from 2.2 (2.0–2.4) at baseline to 2.0 pg/mL (1.8–2.2) (p = 0.02) at follow-up among the TCW. Also the platelet activation biomarkers P-selectin and CD40L decreased significantly [25.4 (24.1–26.6) to 24.4 (22.9–26.0)] ng/mL, p = 0.04 and 125 (114–137) to 105 (96–115) pg/mL, p < 0.001, respectively. ICAM-1 concentrations increased from 249 (238–260) to 254 (243–266) ng/mL (p = 0.02). No significant alterations were observed among the referents when assessed by paired sample t test. Unbeneficial alterations in blood fatty acid composition were observed between baseline and follow-up, mainly among referents. Conclusions: TCW had slightly reduced systemic inflammation...