A component of air, oxygen is essential-breathed plant and animal, the phenomenon of oxidation represent the main source of energy in the life processes. The carbon dioxide in the air is involved in chlorophyll assimilation and atmospheric nitrogen circuit represents one of the links of nitrogen in nature. Normal composition of the air includes (in Vol.% dry atmosphere): nitrogen 78, 09%, oxygen 20, 95%, argon 0.92%, carbon dioxide 0, 03%.
This gas mixture represents more than 99.99% of the air. The rest of about 0, 01% is composed of other gases such as neon, helium, methane, krypton, xenon, ozone, hydrogen, radon. To these are added various ratios of water vapor (on average 0.2 – 3%).
At this time the modern world confront with more types of air pollution. We mean by air pollution present in the atmosphere of certain substances foreign to the normal composition of the air which in terms of concentrations and/or the time of action that causes disorder affecting human health, create discomfort population of a territory, affects environment.
Results from this definition that – in order to be considered pollutants – substances present in the atmosphere must have a negative effect on humans or to the environment. Sources of types of air pollution can classify into two groups: natural sources and artificial sources (results from human activities).
Effect of air pollution on human health
In the course of an act respiratory, the man to stand through his lungs a quantity of 500 cm2 of air, by volume which increases than in the case of a physical effort, be in direct proportion to this effort. In 24 hours in the environment the man was breathing about 15-25 m3 of air. Taking compared with consumption of food and water for 24 hours, the man inhaling on average 15 kg of air while the consumption of water usually does not exceed 2.5kg, and the food 1, 5 kg. Results from these important health data composition atmosphere, to which is added the fact that pulmonary barrier retains only a limited substances came up to the level of socket, once with inspirited air.
From the point of view of hygiene, these types of air pollution influence health through both its chemical composition and in its physical properties (temperature, humidity, air movement, radiation, pressure).
These types of air pollution the chemical composition influence on the health of normal variations in the concentration of components, as well as the action which it carries on this in the air of foreign compounds. Direct effects are represented by changes that appear in the state of health of the population as a result of occupational exposure to pollutants. These changes may result in the order by gravity: increase in mortality, morbidity.
Other types of air pollution are the irritating pollutants they have effects on ocular mucous and especially on respiratory system.
Pollutants fibrosis is another types of air pollution can produce changes in the respiratory system. Carcinogenic pollutants. There are difficulties in estimating the role of air pollutants as causative factors of cancer.