Coal is a fossil fuel that highly contributes to climatic change, polluting not only air but also water and the soil. By burning it, its gases contribute to increase the greenhouse effect and consequently producing global heat. This is affecting all forms of life that depend on these resources, including human beings. Thermal factories of coal for electricity production are the responsible source of CO, CO₂, SO₂ and NOₓ release. During the coal combustion process, several particles are released to air, polluting and being the cause of smog and acid rain. To produce only one tone of energy, coal emits 3.5 tones of CO₂, which is 1.5 more times than gas and 1.3 more times than petroleum CO₂ emission. In spite of its reduced use in the last years, coal is still the principal fuel used by thermal, refineries, chemical, and still work industries. It is also very important to mention that this production is the cause of the destruction of several species´ habitats and ecosystems that surround the mines.
Petroleum pollution is produced by its accidental or intended release in the environment, which produces adverse effects on all forms of life, directly or indirectly. This contamination involves all the operations related to hydrocarbon extraction and its transport, driving to a gradual environment deterioration, affecting soil, water, air, flora, and fauna. The areas occupied by the petroleum extraction installations affect the whole ground surface that ends in a completely degraded place. In superficial water sources, petroleum split and other wastes produce a decrease in oxygen, available solids, organic and inorganic substances. Underground water is affected by an increase in salinity by contamination. Ocean water is affected by conducts break in the bottom, or by ship splits. The air ais affected by gas emissions such as CO and CO₂.
Oil is also a huge contaminator and it generates a dangerous waste that is very harmful to the environment. Its elimination by incineration or split provokes huge pollution problems in the air, water, and ground. In water, it produces an impermeable film that impedes gas exchange and causes suffocation in the living forms that inhabit there. Only one oil liter contaminates one million liters of water. But if the oil is burned it generates nocive gases that are very toxic because of their content in plumb, chloride, phosphorus, sulfur, among others. Only 5 oil liters burned might contaminate 1 million cm³ of air.
