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Occupational exposure limits are the maximum allowable concentrations of hazardous elements in the air. They are defined by scientific laboratories in order to control the level of pollution in different areas. Among the main atmosphere pollutants are large-scale industry, domestic boilers and transport. The portion of each of these pollutants is different from place to place, but industrial companies are considered to be the worst pollutants. The major sources of artificial aerosol pollution of the atmosphere are thermal power plants that burn a large amount of coal with high ash content, concentrating mills, metallurgical, cement, magnesite and soot plants. |
Pollution of soil
The soil cover of the Earth represents one of the most important components of the planet's biosphere. It is the soil layer that defines many processes happening in the biosphere.
As a result of the human's economic activity we witness pollution, change of the composition and sometimes even the destruction of the soil. Today each person's share on earth is less that one hectare of arable land. And this size is constantly decreased due to the unskilful and irresponsible activity of the humans.
Huge areas of fertile land die in mining work, construction of plants and cities. The destruction of forests and natural grass cover, repeated ploughing up of the land without observance of all necessary rules leads to soil erosion – destruction and washout of the fertile layer by water and wind. It's been counted that around 2 billion hectares of fertile land have been lost due to water and wind erosion.
The major importance of the soil lies in the fact that it is able to accumulate organic substances, various chemical elements as well as energy. The soil layer performs the function of biological absorber, destructor and neutralizator of various types of pollution. If this part of the biosphere is destructed the existing functioning of the biosphere in general will be impossible. That's why it is extremely important to study the global biochemical importance of the soil layer, its condition and changes as a result of the anthropogenic activity. One of the types of such anthropogenic activity is the pesticide pollution.
