Evaluation of the effects of PM emitted by specific emission sources on environment and health

The health burden due to particulate matter (PM) air pollution (PM10 and PM2.5) is one of the biggest environmental health concerns in the WHO European Region and around the world. A particular challenge in this research field is about the identification of the physical and chemical characteristics of PM able to reveal the correlation that links fine particle pollutants and respiratory morbidity and mortality. PM is a complex, heterogeneous mixture, whose chemical and physical characteristics (particle size distribution, chemical composition) changes in time and space and depends on various factors (sources, atmospheric chemistry and weather conditions). In literature, most studies associate PM emitted by the major combustion sources, mobile and stationary, with a range of serious health effects, including increased morbidity and mortality from cardiovascular and respiratory conditions. Current knowledge, however, does not allow a quantification of the health effects of PM emissions from different sources or from individual PM components. Therefore, the study of a depth chemical characterization of the individual emissive sources would be helpful in identification of possible PM toxic effects. Another important factor in the assessment of the aspects that link the human health to particulate pollution is the size of the particle to which the population is exposed. In fact, the size of the particles, together with their chemical composition, are fundamental indicator of health risk. Particle size determines in which region of the respiratory tract particles are deposited, as well as the amount of particles deposited. In this optic, a better understanding of the strength of individual emission sources, of the size of the emitted particles and of their chemical composition could facilitate the design of targeted abatement policies more effective to reduce the burden of diseases due to air pollution. My PhD work was carried out in response to all the above-mentioned needs. In fact, during these three years, I have been studying and deepened all those factors (size, emission sources, chemical composition and indicators of oxidative stress) that could be crucial, to the scientific world, for a better understanding of the PM's harmful effects both on humans and on environment. I have been involved in the study of possible techniques able to monitor and characterize as well as possible, the different emission sources, some of which can only be identified by using high timeresolved methods. I have been also involved in the study of different methods that can quantify the capacity of inhaled PM to cause oxidative stress within the lung, which seems to be one of the main mechanisms for the adverse cardio-respiratory health effects observed in epidemiological studies.