TPS 782: Health effects of emf, radiation and light, Johan Friso Foyer, Floor 1, August 28, 2019, 3:00 PM - 4:30 PM
Background/Aim: It is well established that exposure to particulate matter (PM) increases risk of cardiovascular morbidity and mortality, but the exact mechanisms remain unknown. However, few studies have investigated the potential role of particle radioactivity. Previous research has demonstrated that naturally-occurring radionuclides, primarily radon decay products, attach to PM in the accumulation mode. These radionuclides continue to decay and release ionizing radiation after inhalation and deposition in the lungs. This study assesses whether exposure to particle radioactivity is associated with biomarkers of inflammation and endothelial dysfunction in the Normative Aging Study cohort.
Methods: Our study included 753 men in the greater Boston area. Gross beta concentrations, measured at five locations, were used as a surrogate for regional particle radioactivity. We used linear mixed-effects regression models to examine whether particle radioactivity is associated with fibrinogen, C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1), with and without additional adjustment for particle number, black carbon, and PM2.5.
Results: We observed positive and significant associations between particle radioactivity and CRP, ICAM-1 and VCAM-1. An IQR increase in mean seven-day particle radioactivity (1.17 10-4 Bq/m3) was associated with a 4.88% increase in CRP (95% CI: 0.08, 9.91), a 2.79% increase in ICAM-1 (95% CI: 1.43, 4.18), and a 4.26% increase in VCAM-1 (95% CI: 2.48, 6.08). There was no significant association between PR and fibrinogen. The main effects of particle radioactivity remained similar after adjusting for particle number and black carbon. The association between particle radioactivity and ICAM-1 was reduced after adjustment for PM2.5, suggesting potential confounding.
Conclusions: Regional particle radioactivity is positively associated with inflammatory biomarkers, indicating a potential biological pathway for radiation-induced cardiovascular effects.