Effects of Chronic Exposure to Particulate Air Pollution on Cardiovascular System: An Experimental Study Using Mice Models

Abstract

Abstract Our study investigated the chronic effects of short-term and medium-term exposure to urban particulate matter (PM) on cardiovascular system using murine models. Three-week-old Swiss albino mice (Mus musculus) were exposed to vehicular PM for five days (5D) and three months (3M), and some of them were kept in laboratory as control. Blood samples were analyzed using an automated hematological analyzer and cardiac tissues followed histopathological analysis to determine myocardial infarction as well as fibrosis and elastosis of coronary arteries. Results showed depletions (p < 0.1) in packed cell volume, red blood cells, and neutrophils after 3M of PM exposure. The density of neutrophils infiltrated in the myocardium was increased after 5D and 3M of PM exposure (p < 0.05). Higher thickness of arteriolar walls were found in almost all sized arterioles after 3M of PM exposure (p < 0.05) indicating higher content of collagen and elastic fibers, but no evidence of such after 5D of PM exposure. All parameters were compared to the control condition. We conclude that exposure to PM air pollution significantly altered cardiovascular system in animal models signaling that their blood and organs were badly injured.