5/5/09

Nuclear Technology: benefits and risks

The benefits of nuclear technology in agriculture


by Monish Gunawardana*

Nuclear power can be used to wipe out our civilization within a few minutes. In 1945, two atom bombs wiped out millions of civilians in two Japanese cities, Hiroshima and Nagasaki. Today, our planet houses nearly 22,000 nuclear weapons. But let us discuss how to employ nuclear technology to bring food to all people.

Radioisotopes are are used in agriculture to control pests, study fertilizer or prevent waste of grain in stores. At the beginning, isotopes were mainly used for medical diagnosis, with the patient being given the radioisotopes in a chemical form to concentrate in the organ to be studied. The radiation can then be easily detected outside the patient's body by a scanner.

Improving agricultural productivity by utilizing advanced technology is crucial to guarantee food security for all. The Food and Agriculture Organization (FAO) has recognized that nuclear energy can improve development, including agriculture, horticulture, forestry and improved levels of nutrition. The FAO and International Atomic Energy Agency (IAEA) work hand in hand in promoting nuclear-related technologies to achieve these goals.

The IAEA promotes radioisotopes to study the growth and nutrient needs of agricultural crops in dry areas. These studies help agricultural scientists to introduce efficient water management systems and crop varieties to water-deficient lands. The FAO has introduced some fertilizers labeled with nitrogen-isotopes (15N), to use and identify the best growing conditions for crops in dry lands in Burkina Faso, Mali, Niger and Senegal.

Inadequate preventive maintenance generates leakages in the irrigation schemes, while poor irrigation management makes soil saline (saltiness of the soil). Around 40 percent of the world's food is grown utilizing irrigation schemes and 10 percent of agricultural lands in the world have become unproductive by salinity. However, the above-mentioned nuclear-scientific interventions help drought-ridden nations to grow food successfully.

IAEA encourages radioisotope techniques to improve fertilizer applications. It could estimate the exact amount of water and nutrients needed for a certain crop. The optimal use of fertilizers and water helps farmers to grow food with good quality at lower production costs. The application of fertilizers via major irrigation schemes and minor waterways within the farmland can bring many benefits to the farmer. Some of those benefits are saving water, nitrogen fertilizers,labour and farm implements' costs.

Radiation techniques can control pests and insects that destroy food crops. It is used to rear insects en masse and sterilise them with gamma radiation. Then, these unproductive insects are released to compete with wild males for mating. Over time, this nuclear-based technique begins to eradicate insects that are harmful to agricultural crops.

Using Sterile Insects Techniques (SIT), Guam and Marian's islands have eradicated fruit flies. In 2001, the FAO, IAEA and World Health Organization extended SIT programmes to 37 Sub-Saharan African countries to control the Tsetse Fly that causes sleeping sickness and cattle diseases like Magana, which cause US$4 billion economic losses per year.

With the help of nuclear radiation, IAEA/FAO agricultural scientists have introduced nearly 400 varieties of high-yield and disease-resistant rice to Vietnam and other rice -producing countries. This is done by changing the inherited characteristics of plants exposed to radiation.

Protein-rich wheat in India and high-yield rice and early maturing soya beans in Japan are some examples of the new generation of plants bred by radiation technology. These new breeds of plants consume less water, fertilizer and time to produce grains, fruits or vegetables. In addition, they are more resistant to pests and diseases than traditional crops. Therefore, the new strain of plants produced by nuclear applications would trim down the production costs of agriculture and improve the food security of many nations, predominantly in the developing countries.

The Indira Gandhi Center for Atomic Research at Kalppakkam in India, using nuclear tools, introduced advanced varieties of green grams, black grams and red grams. Moreover, it introduced tissue culture in sugarcane in Maharastra region.

Around two billion of people around the world do not have easy access to safe drinking water. They use contaminated water sources. Because of that, water-borne diseases could increase the poverty of developing nations. Under the guidance of the IAEA and FAO, hydrologists using nuclear means try to locate and protect springs and other water sources. Their tool is the isotope. For instance, in an area in Uganda, a community spring began to generate contaminated water. Isotope hydrologists found the source for the spring as a swamp in the mountain. After that they took steps to protect the swamp. Now that spring water is safe and clean.

In Abidjan, Ivory Coast, a few years ago people began to complain about the contaminated ground water. Hydrologists using nitrogen-isotopes identified the reason as the worn-out underground sewage network of the area.

Industrialized nations and emerging economic powers in Asia have recognized the great significance of nuclear applications in agriculture, industries, medicine, water and power supply. The nuclear-scientific approach is a viable solution for global socio-economic advancement.

*Professor, International University of Management, Namibia
Atoms for peace: Extending the Benefits of Nuclear Technologies
http://www-tc.iaea.org/tcweb/archives/articles/atomsforpeace.asp
Through IAEA-supported projects, beneficial nuclear technologies are contributing to national development goals.
by Jihui Qian and Alexander Rogov
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Over the past 40 years, a disease known as rinderpest, or "cattle plague", has been devastating for farmers in Africa, claiming the lives of millions of cattle and severely hurting farm production and income. Especially in the 1980s, serious outbreaks of rinderpest in livestock were reported throughout Africa.

Today, that picture has changed. Out of 18 African countries where cattle once were infested with rinderpest, only two show signs of the disease today. Instrumental to this remarkable turnabout has been a Pan-African campaign that incorporated the application of a new nuclear-based testing technique developed jointly by the IAEA, Food and Agriculture Organization (FAO) of the United Nations, and a laboratory in the United Kingdom in 1987. The application has radically increased the effectiveness of vaccination campaigns against cattle plague, enabling African countries to declare themselves free of the disease. Veterinarians in these countries received support from the IAEA's technical co-operation programme and an FAO/IAEA coordinated research programme. They were supplied with necessary testing kits, equipment, training, and technical support to ensure the correct use of the technique in national veterinary laboratories. Participating laboratories throughout Africa now have acquired the expertise and skills they need to carry out effective testing.

The project's success is leading to similar work in other regions of the world. A global rinderpest campaign has been launched with the aim of eradicating the disease over the next 20 years. Under a 4-year IAEA technical co-operation project, the techniques developed through the FAO/IAEA's work in Africa will be part of efforts for rinderpest surveillance and control in West Asia. Countries there currently are suffering millions of dollars in losses from animal deaths. The IAEA regional project aims to help these countries eradicate rinderpest by the turn of the century.
The case of rinderpest is just one example of how international and national scientists are working together to bring practical benefits to people through technology-transfer projects supported by the IAEA. In other fields as well including medicine, environmental protection, and food preservation, for example - nearly, 1300 IAEA-supported projects are making key contributions around the world. This article looks at the kinds of projects cooperatively undertaken through IAEA mechanisms to extend the reach of beneficial nuclear technologies in response in increasing demands for technical support and assistance from its Member States.
Evolution of international nuclear co-operation

In the early 1950s, the international community was first becoming aware of the great opportunities that peaceful applications of atomic energy could offer for economic and social development. It was also becoming apparent that, for most countries, these opportunities could be materialized in a most effective manner through extensive and concerted international efforts.

In this environment, on 4 December 1954, the United Nations General Assembly unanimously passed an "Atoms for Peace" resolution expressing the hope that an international atomic energy agency would be established without delay to facilitate the use by the entire world of atomic energy for peaceful purposes, and to encourage international co-operation in the further development and practical use of atomic energy for the benefit of humanity.

At the time when the IAEA was established in 1957, only a limited number of countries had knowledge and experience in nuclear research, and especially its practical application. At the first International Conference on the Peaceful Uses of Atomic Energy, held in Geneva in August 1955 and attended by scientists and engineers from 73 countries, less than half of participating States were able to present reports on nuclear science or technology and only 12 of these States were from developing areas of the world.

In framing the IAEA's Statute, governments sought to create an international institution through which countries could receive multilateral technical assistance on peaceful nuclear research and applications. The Statute stipulates a range of conditions for countries to receive such assistance. These include, inter alia, the usefulness of the project, including its scientific and technical feasibility; the adequacy of plans, funds, and technical personnel to assure the effective execution of the project; and the adequacy of proposed health and safety standards for handling and storing materials and for operating facilities.

Back in 1957, however, the basis for technical assistance activities was fairly weak. The sphere of co-operation was relatively limited covering mainly nuclear power and aspects of its fuel cycle, and to a certain extent some aspects of radiation applications. Very few peaceful nuclear technologies had reached the level of maturity which enabled them to be effectively used for practical applications. At that time as well, most developing countries were not yet at the stage where they could effectively apply nuclear science and technology. It should also be noted that, in the early years, none of the three partners involved in the technical assistance process i.e. donor countries, recipient countries, and the IAEA - had neither the required experience nor administrative arrangements for multilateral intergovernmental co-operation.

Today, the situation is different. Most IAEA Member States from the developing world have gained knowledge and experience in many fields of nuclear research and applications, mainly those related to basic human needs. Mechanisms for technology transfer have been put into place, and their effectiveness is continually reviewed. IAEA activities cover practically all areas of peaceful applications of nuclear energy, and interest in receiving technical assistance is growing.

People in many countries around the world are seeing benefits of nuclear technologies in their lives, through IAEA-supported projects in fields of health care, water management, agriculture, and industry, for example. (Credits: J: Aranyossy and V. Mouchkin, IAEA)
Priorities and needs

What kinds of technical assistance are countries receiving? In terms of total annual disbursements through the IAEA's technical co-operation programme, the largest share is for projects related to nuclear applications in food and agriculture, which accounted for about 22% of disbursements in 1994. Nuclear-related methods are widely used in developing countries in such areas as plant breeding, soil fertility studies, insect and pest control, animal production and health, and studies of the fertilizer efficiency and the fate of agrochemicals and residues. The technology of food irradiation additionally is finding increasing acceptance as an effective means of protecting agriculture products from spoilage, and as a method for controlling pathogens associated with serious food-borne diseases and for meeting the strict quarantine requirements of international food trade.

Another major area of interest is the use of nuclear technologies in physical and chemical sciences, and in fields of industry and earth science. This includes the utilization of research reactors and particle accelerators for scientific studies, production of isotopes; the application, maintenance and repair of nuclear instrumentation; and the preparation and utilization of radiopharmaceuticals. Over the 1990-94 period, the share of total disbursements in this area have ranged between 18% and 25%. Other areas showing high levels of interest are nuclear applications in industry and earth sciences - including non-destructive testing of materials and products, radiation processing, and development of water resources, for example and nuclear-related health care and treatment. Greater support, for instance, is being requested in the use of nuclear techniques for the diagnosis of many diseases, such as leishmaniasis, Chagas disease, iodine deficiencies, and sickle cell diseases. At the same time, the use of ionizing radiation to treat cancer is drawing more and more interest. Currently the IAEA has 40 technical co-operation projects associated with radiotherapy in 29 countries. Additionally, nuclear methods and technologies are used for sterilization of biological tissues and medical supplies, and for nutritional and health-related environmental studies.
An area of shifting demand is nuclear power and safety. While nuclear power programmes in many countries have been cut back or halted, there is increasing awareness of the needs for nuclear safety and radiation protection. The share of disbursements on nuclear power has dropped from about 12% in the late 1980s to 6% in the 1990s, whereas the share for safety and radiation protection has grown. Projects being supported include those related to strengthening national infrastructures for radiation protection; occupational safety of radiation workers; safety of nuclear installations; the safe management, storage, and disposal of radioactive wastes; and nuclear emergency planning and preparedness.

On average over the past 5 years, countries have received technical assistance from the IAEA valued at about US $40 million per year through expert services, provision of equipment, and training activities. All told over the past 25 years, the cumulative resources available to the IAEA's technical co-operation programme amount to nearly US $690 million.
Realizing the benefits

As the rinderpest example illustrates, a number of techniques developed and applied with the IAEA's assistance are significantly contributing to the solution of serious problems hampering social and economic development. Some selected other cases may help to indicate the number of different ways in which the IAEA's assistance can be applied.

Water resources. The assessment and development of water resources has been a major area of IAEA activity for more than 30 years. Nuclear and isotope techniques play a valuable role in hydrological investigations. Under one current project, in Venezuela, IAEA scientists are helping local water authorities in Caracas study the potential of an aquifer to provide additional water for residential, agricultural, and industrial needs. A rapid increase in the population of Caracas has led to a deficit of nearly 20% in the water supply, and more water resources must be found. Studies will help Venezuelan authorities make decisions concerning the best use of the aquifer, and how to protect its water from pollution.

Animal health and productivity. Buffaloes and cattle in Asia are fed mainly with rice straw and native grasses. However, these materials are very indigestible and have only limited amounts of the protein, energy, and minerals needed to provide a balanced diet. Poor nutrition seriously compromises the ability of the animals to produce meat and milk and to provide draught power. Through projects jointly supported by the IAEA and United Nations Development Programme (UNDP), assistance was provided to India and Indonesia in using isotopes for investigating the efficiency of the processes involved in feed digestion. As a result, the best combination of local materials for supplementing grass or straw was determined.
In both countries the effect of the introduction of this feed supplementation method has been very high. For example, in India the amount of milk collected by the largest milk co-operative in 1989 increased by 30%, and the price was 25% less than the price of producing milk by the other methods of feed supplementation.
Quality control in industry. Non-destructive testing (NDT) techniques are widely applied in industry and manufacturing for quality control purposes. In Latin America and the Caribbean, an IAEA-supported NDT regional project involving 18 countries was conducted from 1983-94. The overall objective was to assist them in developing an autonomous capability for applying NDT, largely by providing support in areas of training.

The evaluation review carried out by independent experts in 1994 showed that the project had been instrumental in providing the region with a significant technological tool for the advancement of the region's industrialization. This enabled the development of local industries and the displacement of NDT services previously provided from outside the region. The project marked a significant change for the region's own technological development. In previous years, the input from experts from outside of the region was the dominant mode of dissemination of NDT technology. This was often in the context of regional courses, with typically one participant from each project country. Gradually, the dominant mode changed from using external experts to using regional experts and further evolved to the use of national experts teaching courses solely in their respective countries.

Health care. Nuclear and related techniques play an especially vital role in health care and treatment. Among important diagnostic tools is a technique known as radioimmunoassay. With the IAEA's support, more than 250 radioinimunoassay laboratories have been established or upgraded in Africa, Asia, and Latin America, and supplied with reagents in bulk form. has allowed recipient countries to provide reasonable clinical diagnostic services covering important substances such as hormones, vitamins, enzymes and even some tumor markers. The cost of each test is less than US 50 cents per patient sample, which on average is ten times less than the application of complete commercial kits. In some countries, where some of the primary reagents needed are being produced locally, the cost per test is significantly lower. More important than the lower cost is the fact that many people now have access to reliable diagnostic tests that play a key role in the improvement of their health care and treatment.
Future directions

In its current and planned programmes, the IAEA is placing increasingly more emphasis on cost-effective projects that promise significant social and economic benefits, that have a lasting and environmentally sound impact on a country's development, and that clearly demonstrate the value of nuclear applications for end users. The IAEA's Member States have strongly supported this move towards impact-oriented technical co-operation. At an IAEA Technical Cooperation Policy Review Seminar in September 1994, for example, governmental representatives provided the Agency with valuable recommendations regarding the practical implementation of projects important to them.

Undoubtedly the major challenge facing the IAEA's technical co-operation programme in years ahead is the availability of sufficient financial resources to effectively carry out approved projects. In terms of its funding base, the IAEA occupies a place far behind large bilateral and multilateral agencies. Even so, the trend in contributions to the IAEA's technical co-operation programme over the past 5 years has been negative, and many sound projects have had to go unfunded. In response to the situation, the IAEA has taken a number of administrative and programmatic measures intended to stretch its limited resources so as to obtain the best possible results.

These efforts are part of steps to improve programme efficiency, and to attract greater resources enabling the IAEA to enhance its support for technology-transfer activities that are not only operationally sound but visibly effective. As the main channel for global nuclear co-operation, the IAEA possesses an exceptionally high level of technical expertise and experience to identify and carry out a multitude of projects that can make a lasting difference to a country's sustainable development.

RISKS OF NUCLEAR POWER
http://www.physics.isu.edu/radinf/np-risk.htm
Bernard L. Cohen, Sc.D.
Professor at the University of Pittsburgh
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Radiation

The principal risks associated with nuclear power arise from health effects of radiation. This radiation consists of subatomic particles traveling at or near the velocity of light---186,000 miles per second. They can penetrate deep inside the human body where they can damage biological cells and thereby initiate a cancer. If they strike sex cells, they can cause genetic diseases in progeny.

Radiation occurs naturally in our environment; a typical person is, and always has been struck by 15,000 particles of radiation every second from natural sources, and an average medical X-ray involves being struck by 100 billion. While this may seem to be very dangerous, it is not, because the probability for a particle of radiation entering a human body to cause a cancer or a genetic disease is only one chance in 30 million billion (30 quintillion).

Nuclear power technology produces materials that are active in emitting radiation and are therefore called "radioactive". These materials can come into contact with people principally through small releases during routine plant operation, accidents in nuclear power plants, accidents in transporting radioactive materials, and escape of radioactive wastes from confinement systems. We will discuss these separately, but all of them taken together, with accidents treated probabilistically, will eventually expose the average American to about 0.2% of his exposure from natural radiation. Since natural radiation is estimated to cause about 1% of all cancers, radiation due to nuclear technology should eventually increase our cancer risk by 0.002% (one part in 50,000), reducing our life expectancy by less than one hour. By comparison, our loss of life expectancy from competitive electricity generation technologies, burning coal, oil, or gas, is estimated to range from 3 to 40 days.
There has been much misunderstanding on genetic diseases due to radiation. The risks are somewhat less than the cancer risks; for example, among the Japanese A-bomb survivors from Hiroshima and Nagasaki, there have been about 400 extra cancer deaths among the 100,000 people in the follow-up group, but there have been no extra genetic diseases among their progeny. Since there is no possible way for the cells in our bodies to distinguish between natural radiation and radiation from the nuclear industry, the latter cannot cause new types of genetic diseases or deformities (e.g., bionic man), or threaten the "human race". Other causes of genetic disease include delayed parenthood (children of older parents have higher incidence) and men wearing pants (this warms the gonads, increasing the frequency of spontaneous mutations). The genetic risks of nuclear power are equivalent to delaying parenthood by 2.5 days, or of men wearing pants an extra 8 hours per year. Much can be done to avert genetic diseases utilizing currently available technology; if 1% of the taxes paid by the nuclear industry were used to further implement this technology, 80 cases of genetic disease would be averted for each case caused by the nuclear industry.
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Reactor accidents
The nuclear power plant design strategy for preventing accidents and mitigating their potential effects is "defense in depth"--- if something fails, there is a back-up system to limit the harm done, if that system should also fail there is another back-up system for it, etc., etc. Of course it is possible that each system in this series of back-ups might fail one after the other, but the probability for that is exceedingly small. The Media often publicize a failure of some particular system in some plant, implying that it was a close call" on disaster; they completely miss the point of defense in depth which easily takes care of such failures. Even in the Three Mile Island accident where at least two equipment failures were severely compounded by human errors, two lines of defense were still not breached--- essentially all of the radioactivity remained sealed in the thick steel reactor vessel, and that vessel was sealed inside the heavily reinforced concrete and steel lined "containment" building which was never even challenged. It was clearly not a close call on disaster to the surrounding population. The Soviet Chernobyl reactor, built on a much less safe design concept, did not have such a containment structure; if it did, that disaster would have been averted.

Risks from reactor accidents are estimated by the rapidly developing science of "probabilistic risk analysis" (PRA). A PRA must be done separately for each power plant (at a cost of $5 million) but we give typical results here: A fuel melt-down might be expected once in 20,000 years of reactor operation. In 2 out of 3 melt-downs there would be no deaths, in 1 out of 5 there would be over 1000 deaths, and in 1 out of 100,000 there would be 50,000 deaths. The average for all meltdowns would be 400 deaths. Since air pollution from coal burning is estimated to be causing 10,000 deaths per year, there would have to be 25 melt-downs each year for nuclear power to be as dangerous as coal burning.

Of course deaths from coal burning air pollution are not noticeable, but the same is true for the cancer deaths from reactor accidents. In the worst accident considered, expected once in 100,000 melt-downs (once in 2 billion years of reactor operation), the cancer deaths would be among 10 million people, increasing their cancer risk typically from 20% (the current U.S. average) to 20.5%. This is much less than the geographical variation--- 22% in New England to 17% in the Rocky Mountain states.
Very high radiation doses can destroy body functions and lead to death within 60 days, but such "noticeable" deaths would be expected in only 2% of reactor melt-down accidents; there would be over 100 in 0.2% of meltdowns, and 3500 in 1 out of 100,000 melt-downs. To date, the largest number of noticeable deaths from coal burning was in an air pollution incident (London, 1952) where there were 3500 extra deaths in one week. Of course the nuclear accidents are hypothetical and there are many much worse hypothetical accidents in other electricity generation technologies; e.g., there are hydroelectric dams in California whose sudden failure could cause 200,000 deaths.
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Radioactive Waste
The radioactive waste products from the nuclear industry must be isolated from contact with people for very long time periods. The bulk of the radioactivity is contained in the spent fuel, which is quite small in volume and therefore easily handled with great care. This "high level waste" will be converted to a rock-like form and emplaced in the natural habitat of rocks, deep underground. The average lifetime of a rock in that environment is one billion years. If the waste behaves like other rock, it is easily shown that the waste generated by one nuclear power plant will eventually, over millions of years (if there is no cure found for cancer), cause one death from 50 years of operation. By comparison, the wastes from coal burning plants that end up in the ground will eventually cause several thousand deaths from generating the same amount of electricity.

The much larger volume of much less radioactive (low level) waste from nuclear plants will be buried at shallow depths (typically 20 feet) in soil. If we assume that this material immediately becomes dispersed through the soil between the surface and ground water depth (despite elaborate measures to maintain waste package integrity) and behaves like the same materials that are present naturally in soil (there is extensive evidence confirming such behavior), the death toll from this low level waste would be 5% of that from the high level waste discussed in the previous paragraph.
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Other Radiation Problems
The effects of routine releases of radioactivity from nuclear plants depend somewhat on how the spent fuel is handled. A typical estimate is that they may reduce our life expectancy by 15 minutes.

Potential problems from accidents in transport of radioactive materials are largely neutralized by elaborate packaging. A great deal of such transport has taken place over the past 50 years and there have been numerous accidents, including fatal ones. However, from all of these accidents combined, there is less than a 1% chance that even a single death will ever result from radiation exposure. Probabilistic risk analyses indicate that we can expect less than one death per century in U.S. from this source.

Mining uranium to fuel nuclear power plants leaves "mill tailings", the residues from chemical processing of the ore, which lead to radon exposures to the public. However, these effects are grossly over-compensated by the fact that mining uranium out of the ground reduces future radon exposures. By comparison, coal burning leaves ashes that increase future radon exposures. The all-inclusive estimates of radon effects are that one nuclear power plant operating for one year will eventually avert a few hundred deaths, while an equivalent coal burning plant will eventually cause 30 deaths.

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Contributed by NguyenDucNam as part of his homework. Thanks Nam

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