Introduction -
According to the International Atomic Energy Agency (IAEA), Radioactive Contamination also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirable.
Radioactive pollution happens due to the release of radioactive materials or wastes into the environment. The use of nuclear energy produces radioactive wastes. The disposal of nuclear waste needs a lot of money and expertise. If radioactive substances or wastes are not disposed of properly, then they will pollute air, water and soil.
About 20% of radiation is estimated to be exposed due to human activities. Human activities with radioactive materials include mining, handling and storing radioactive waste, working in nuclear power plants to generate energy, and the use of radiation in medicine and research.
How does Radioactive pollution occur?
Radioactive pollution can occur naturally and man-made or artificially.
Natural radioactivity occurs naturally in our environment. Some radioactive elements such as uranium and thorium are present in rocks and soil.
Interestingly, ‘Our bodies contain specific definite amounts of the radioactive isotopes potassium-40 and carbon-14. About 38,000 atoms of potassium-40 and 1200 atoms of carbon-14 explode in our bodies every second.
Artificially induced radioactivity occurs in two ways:
Nuclear Fission - a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy.
Nuclear Fusion - Nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
Nuclear fission releases more radioactive waste and produces less energy than nuclear fusion.
Examples of Radioactive Pollution -
Scientists and administrators had assured us that nuclear power was safe, given all the foolproof features of reactors. Yet, accidents, big and small, have occurred in nuclear establishments all over the world.
Nuclear power stations do have many safety features. The accidents have shown, however, that such features can never be a total defence against human errors and unforeseen technical problems.
The worst nuclear accident to date is the one that occurred in Chornobyl in 1986. Accidents also occurred in the Sellafield nuclear complex in the UK (1957), Hanford Nuclear Complex - in the US (1973), the Three Mile Island Plant - in the US (1979), and Fukushima- Japan (2011), Several other minor accidents have also been reported from Japan, which has a large number of nuclear power stations.
What is Nuclear Waste and Why is it a Problem?
There are three types of radioactive waste: Low-level, Intermediate-level, and high-level Hospitals, Laboratories, and other buildings where radioactive technology is used emit low-level radiation, which is not considered a health hazard.
Intermediate-level waste consists of substances from nuclear power stations like cleaning agents and sludge. This material is bulky and decays slowly. Hence, it is encased in bitumen or concrete before being stored. Until 1980, this kind of waste was just dumped in the ocean. Since then, it has been stored in deep landfill sites because of an international convention against ocean dumping.
High-level nuclear waste is extremely dangerous and must be isolated for thousands of years. This is mostly the spent nuclear fuel that comes from nuclear reprocessing plants. There is no definitely safe method of storing this waste. Tonnes of this hazardous waste are piling up all over the world.
Though nuclear bombs have been used only once so far (by the US on Hiroshima and Nagasaki in 1945), innumerable nuclear tests have been conducted since then by a number of countries, including India and Pakistan. During the first two decades, the tests were conducted above ground and thousands of unsuspecting people and many habitations were exposed to dangerous levels of radiation. Bikini Atoll in the Marshall Islands, and some desert regions of Australia and the US were the worst affected. Since 1963, the tests have been conducted underground, but there is still contamination of air, soil, and water.
Impact of Radioactive Radiation -
The effects of radiation may be instantaneous, prolonged or delayed. Even it can be carried to future generations or may result in the production of defective embryos. All kinds of impacts depend on two major factors: doses of radiation exposure and duration of such exposures.
The effects of radiation are thus grouped on the basis of effects on different cellular component levels, into the following:
- Radiation effect on DNA
- Radiation effect on chromosome
- Radiation effect on cellular level and
- Tissue response to radiation.
- In addition, there are a number of gross physiological effects on the whole body including defects of circulatory, digestive and neurotic systems.
Now we discussed how exposure to Nuclear Radiation affects health.
How does Exposure to Nuclear Radiation Affect Health?
Any nuclear explosion or accident releases radioactive material, which can cause radiation sickness. The impact on human health depends on the amount of radiation received by the body. Radiation exposure above a certain threshold, usually received by workers and emergency teams in the accident zone, causes acute effects within hours of exposure, ranging from skin rashes, vomiting and diarrhoea, to coma and death. For example, all the workers, who put out the fires during the Chernobyl accident, died soon after.
Depending on the scale of the accident, large areas around the accident zone could get contaminated by radiation. Thus, people, animals, plants, etc. could be affected and experience long-term health problems. For example, during the years following the Chernobyl explosion, more than 6000 people in the area developed thyroid cancer, probably after drinking contaminated milk as children. The cancer showed up between four and ten years after the accident.
Exposure to radiation affects a cell’s ability to conduct repair and reproduction. It increases the long-term risk of cancers such as leukemia and lymphoma. It can also cause genetic effects, birth defects, cataracts, and other organ and tissue defects.
Radiation Protection -
The radiation hazards were not considered seriously earlier as a major environmental threat to human health. However, the realization of the deleterious effects of radiation hazards in recent years necessitates the need for protection against radiation hazards.
Global banning of nuclear weapons, safe disposal of nuclear plant wastes and proper dumping of radioactive materials used for therapeutic purposes etc. are the major activities undertaken currently as a measure against radiation hazards. In addition, the workers handling radioactive materials are required to undertake appropriate protection measures while working at the premises of nuclear plants. The International Atomic Energy Commission has set up a standard guideline for the said purpose.
Frequently Asked Questions (FAQs)
Question - What is the Radioactive Pollution?
Answer - According to the International Atomic Energy Agency (IAEA), Radioactive Contamination also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirable.
Question - What is the main source of radioactive Pollution?
Answer - Nuclear power plants are the main sources of radioactive pollution. Also, Nuclear weapons factories and wastes of radioactive materials play a vital role in radioactive pollution.
Question - What is the difference between nuclear fission and nuclear fusion?
Answer - Nuclear Fission - a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy.
Nuclear Fusion - Nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
Nuclear fission releases more radioactive waste and produces less energy than nuclear fusion.
Question - What is an example of nuclear fusion?
Answer - Nuclear fusion occurs when two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
In the core of the Sun 600 million tons of hydrogen are converted into Helium every second and creates huge amounts of energy.
Question - What are the harmful effects of radioactive radiation?
Answer - Any nuclear explosion or accident releases radioactive material, which can cause radiation sickness. The impact on human health depends on the amount of radiation received by the body. Radiation exposure above a certain threshold, usually received by workers and emergency teams in the accident zone, causes acute effects within hours of exposure, ranging from skin rashes, vomiting and diarrhoea, to coma and death.
For example, all the workers, who put out the fires during the Chernobyl accident, died soon after.
Question - What is the radiation Protection?
Answer -
- The International Atomic Energy Commission has set up a standard guideline for radioactive protection that aims to reduce unnecessary radiation and minimize the harmful effects of ionizing radiation.
- Global banning of nuclear weapons, safe disposal of nuclear plant wastes and proper dumping of radioactive materials used for therapeutic purposes etc.