Particulate matter is an aerosol of small solid particles classified according to their size. Airborne particles are usually measured in Total Suspended Dust. PM10 when the average aerodynamic diameter is less than 10 microns can reach the lungs, PM2.5 when their average aerodynamic diameter is less than 2.5 microns more harmful because they can pass through the filters of the upper respiratory airways.
Attention is now focusing on the health impact of even smaller particles, PM0.1 and so-called nanodusts, which penetrating further deeply are believed to be even more harmful. According to WHO, particulate matter pollution is responsible for shortening 1 year of life on average.
The pathologies that show a significantly higher risk are those involving the cardiovascular and respiratory systems, including lung tumours. The Cardiovascular Effects of Particulate Air Pollution study, published in the Annual review of medicine, told: "Inhalation of fine particulate matter (PM2.5), produced by the combustion of fossil fuels, is an important risk factor for cardiovascular disease.
Exposure to PM2.5 has been linked to increases in blood pressure, thrombosis, and insulin resistance. It also induces vascular injury and accelerates atherogenesis.Results from animal models corroborate epidemiological evidence and suggest that the cardiovascular effects of PM2.5 may be attributable, in part, to oxidative stress, inflammation, and the activation of the autonomic nervous system.Although the underlying mechanisms remain unclear, there is robust evidence that long-term exposure to PM2.5 is associated with premature mortality due to heart failure, stoke, and ischemic heart disease." PM10 mainly affects the respiratory and cardiovascular systems, PM10 tends to settle in the respiratory tract and affects various parts of the respiratory system based on its size, in fact PM10 (particles with a diameter of less than 10 microns) tend to settle in the higher (pharynx) while with smaller diameters the dust tends to settle deeper and deeper until it also reaches the alveolar walls (PM0.65), these dusts can lead to the onset of tumors and various ailments.
The negative effects of carbon monoxide on human health are related to the ability of CO to join blood hemoglobin forming carboxyhemoglobin (COHb). In this way, CO occupies the place normally occupied by oxygen, so as to reduce the oxygen transport capacity of the blood and consequently the amount of oxygen that the blood leaves in the tissues.