Characterization of Particulate Matter in Urban Traffic Roads and Health Effects on the Pulmonary System in Mice with Lung Inflammation

摘要

Introduction: Traffic is a major contributor to air pollution in Indian cities, and traffic-related exposure has been shown to induce acute inflammation in humans, both in chamber studies using diesel exhaust and in real-life environments. In urban centers, diesel exhaust particles are considered to be the hazardous pollutants released from automotive engines due to their aerodynamic and chemical characteristics. Methods: Emissions of PM_(2.5) and PM10 were estimated using a mathematical model incorporating number of vehicles and their emission factors, and correlated significantly with experimental ambient PM concentrations. Elemental composition of PM was analyzed using Energy Dispersive X-Ray (EDX), also referred to as Energy Dispersive Spectroscopy (EDS) method. Preparation of BAL was done following Harrod's protocol with some modifications. Within 2h following the end of particle exposure (5-90 days) mice were anesthetized using chloroform; total cell count and viability determined by Nebur's hemocytometer. Results: EDX analysis found that particulate matter was dominated by black carbon (C) about 56% affected mostly by tail end pipe emissions. The samples were also rich in elements like silicon (Si), iron (Fe), calcium (Ca), aluminium (Al), sodium (Na) and potassium (K) either in single elements or as chemical compounds. There was a significant reduction of the bronchoalveolar lavage lymphocyte cell numbers (08.75) in mice after 30 and 90 days exposure. Percent viability of leucocytes has decreased and differential cell of macrophages and neutophils were increased in BAL fluid following mice exposure to PM_(2.5) in different intervals. Conclusion: Exposure to the mixture of suspended particulate matter particles induces pathological changes, differential cell counts and inflammatory response in the lungs of mice in a dose and duration dependent pattern. The responses observed from the present study are associated with the bioavailable of inhaled particulate mixtures.