Nuclear energy is a form of energy that’s released during nuclear reactions (splitting of atoms) and has been used to generate electricity. Nuclear energy is a kind of clean energy because it doesn’t release pollutants such as C02 to the atmosphere.
Despite the advantage of nuclear energy the big problem is the waste generation in the nuclear reaction, which gives rise to a kind of pollution called radioactivity or radioactive pollution.
Radioactivity is radioactive decay or emission of particles (a, a, a, neutron, proton or heavier particles) from an atom or nucleus. Thermodynamic instability of a nucleus leads to its spontaneous decay to a more stable nucleus.
The time that it takes for half way of decaying process is called half- life, and this differs for each radioactive element. It possibly takes up to 4.5 billion years (Uranium 238) and as short as 8 days (Iodine 131).
This process is not affected by external factors such as pressure or temperature. The unit of radioactivity is Becquerel. One Becquerel is equal to one disintegration of nuclei per second.
Sources of radioactive pollution
The major sources that lead to radioactive pollution can be classified in to the following categories:
• Nuclear power plants
• Nuclear weapon
• Disposal of nuclear waste
• Uranium mining
Impact of radioactive pollution on human health
When high radiations like ± or 2 or 3 strike human body, they penetrate the tissue and transfer their energy. The energy of radiation damages the molecules of the cells.
The extent of damage depends upon exposure to the amount of radiation and is measured in radiations (radiation absorbed doses). One radiation is 100 ergs of energy deposited per gram of tissue.
The effects of radiation on health depend upon the type, energy and amount of radiation, age of individual and external and internal exposure. Ionizing radiations may produce three types of biological effects in all living organisms including plants.
i) Carcinogenic effects (causes cancer)
ii) Mutagenic effects (causes change in genetic material)
iii) Tetragenic effects (causes defects in the development of embryo)
Radioactive waste management
Radioactive waste management is required to protect humans and environment from any harmful effects of ionizing radiation. The waste treatment processes for control of radioactive waste can be classified into the following categories:
i) Transfer Technologies (Removal of radioactive waste and transfer them to another medium e.g. filtration, ion exchange and reverse osmosis)
ii) Concentration Technologies (Reduction of waste volume e.g. evaporation, crystallization, precipitation and centrifugation)
iii) Transformation Technologies (Concentration of radioactive waste by changing its physical form e.g. incineration, calcinations and compaction)