Evaluation of Histological Findings of Airways of Rats Exposed to Highly Polluted Indoor Air in Offices

Humans are exposed to chemicals and PM (particulate matter), including ultrafine particles (nanoparticles), mainly through inhalation. This creates a risk to their health. Another effect to exposure is expression of cytokines and their role in lung inflammation and morphpathogenesis. We conducted a pilot project based on testing of realistic exposure scenarios by describing morphological changes of the respiratory tract in Wistar rats (male) during a 30-day exposure in office where there was high intensity of printing activities. Tracheal tissue of experimental animals had increasing concentrations of inflammatory interleukin IL-1 and decreasing concentrations of IL-6 and TNF-α. The lungs of the experimental animals tended to show focal infiltration of inflammatory cells, vascular plethora, focal and/or diffuse localisation of lymphatic nodules, and also vascular sclerosis and focal emphysema. The results suggested potential dangerous and adverse effect of poor indoor air quality (particles, including nanoparticles, and chemical compounds) on respiratory tract tissue of rats.