The deal virtually lifted the de-facto international ban on the trade of nuclear materials and equipments related with the nuclear industry. The deal and other related agreements were signed in October 2008. However, nothing much has changed in the Indian nuclear scenario.
India is still unable to buy nuclear fuel from nuclear material abundant countries like Australia. Indian nuclear facilities are not able to buy nuclear related equipments, monitoring instruments and systems from western countries.
Now, in a major breakthrough it is reported that US has permitted US firms to collaborate with Indian companies to manufacture nuclear related components. Even Australia which till now reluctant to sell uranium to India, is willing to sell uranium to boost its economy! Good for India, because price of uranium has fallen from $140 (2007) to $50 a pound after the Fukushima nuclear disaster.
The developments will help the seller countries to boost their sagging economies, and for India to buy the uranium fuel for the reactors and much needed equipments for the safe operation of nuclear fuel cycle facilities.
Wednesday, November 16, 2011
Monday, October 17, 2011
Tritium exposure - Kalpakkam
This has reference to the news item in the Times of India dt. 17 October, 2011: “Staff exposed to nuclear radiation – Tritium risk for some Kalpakkam workers”.
The news item states that some workers are exposed to nuclear radiation above permissible levels.
By going by the report, none was exposed to doses above permissible. Exposure to Investigation Levels which are 3/10th of the permissible levels is not an issue at all. In fact, tritium is the least radiotoxic radioisotope and hence least harmful. As a matter of abundant precaution, these levels of exposures are also investigated and corrective actions taken.
It is unfair to the nuclear industry to misquote the report and raise hue and cry on this normal exposure situation in any nuclear reactor.
The news item states that some workers are exposed to nuclear radiation above permissible levels.
By going by the report, none was exposed to doses above permissible. Exposure to Investigation Levels which are 3/10th of the permissible levels is not an issue at all. In fact, tritium is the least radiotoxic radioisotope and hence least harmful. As a matter of abundant precaution, these levels of exposures are also investigated and corrective actions taken.
It is unfair to the nuclear industry to misquote the report and raise hue and cry on this normal exposure situation in any nuclear reactor.
Saturday, October 1, 2011
Suppression of experimental evidence against LNT
This has reference to the article “Will the LNT Controversy ever be solved?” appeared in the July issue of the Express Healthcare. The following information appeared in HINDU (dated 22nd Sept. 2011) supports the view expressed in the article.
American geneticist Hermann J. Muller was awarded the 1946 Nobel Prize in medicine for his discovery that X-rays induce genetic mutations. In his Nobel Prize Lecture of December 12, 1946, Muller argued that the dose–response for radiation-induced germ cell mutations was linear and that there was “no escape from the conclusion that there is no threshold”. Muller and Curt Stern (the other geneticist) had done many of the key experiments. The fruit fly germ cell mutations experimental results at the University of Rochester failed to support the linear dose-response model at low exposure levels. However, in Muller's speech, he insisted there was "no escape from the conclusion that there is no threshold." Stern raised no objection. It is reported that the two successfully suppressed last-minute evidence against the LNT from the fruit fly experiments.
According to the Edward J. Calabrese, a Professor of Toxicology at the University of Massachusetts, School of Public Health, Amherst, uncovered the correspondence between Muller and Stern. He said, Muller’s decision not to mention the key scientific evidence against his position has had a far-reaching impact on our approach to regulating radiation and chemical exposure. In fact, Calabrese’s career research shows that low doses of some chemicals and radiation are benign or even helpful.
Within a year, National Academy of Sciences (NAS) was forced to accept the linear model for gonadal mutations, the practice was extrapolated to somatic cells and cancer. Twenty years later, NAS adopted the linear approach for chemicals. Soon thereafter, the U.S. Environmental Protection Agency announced it would use the linear model for risk assessment. The International Commission of Radiological protection also assumed the LNT as the basis for giving the recommendations for radiological protection.
If the truth was to be told, probably the nuclear industry could have drastically different exposure standards today, and far less fear about exposures to radiation. The resources, world-wide, spent on over-protection could have been better spent on healthcare in under-developed countries.
American geneticist Hermann J. Muller was awarded the 1946 Nobel Prize in medicine for his discovery that X-rays induce genetic mutations. In his Nobel Prize Lecture of December 12, 1946, Muller argued that the dose–response for radiation-induced germ cell mutations was linear and that there was “no escape from the conclusion that there is no threshold”. Muller and Curt Stern (the other geneticist) had done many of the key experiments. The fruit fly germ cell mutations experimental results at the University of Rochester failed to support the linear dose-response model at low exposure levels. However, in Muller's speech, he insisted there was "no escape from the conclusion that there is no threshold." Stern raised no objection. It is reported that the two successfully suppressed last-minute evidence against the LNT from the fruit fly experiments.
According to the Edward J. Calabrese, a Professor of Toxicology at the University of Massachusetts, School of Public Health, Amherst, uncovered the correspondence between Muller and Stern. He said, Muller’s decision not to mention the key scientific evidence against his position has had a far-reaching impact on our approach to regulating radiation and chemical exposure. In fact, Calabrese’s career research shows that low doses of some chemicals and radiation are benign or even helpful.
Within a year, National Academy of Sciences (NAS) was forced to accept the linear model for gonadal mutations, the practice was extrapolated to somatic cells and cancer. Twenty years later, NAS adopted the linear approach for chemicals. Soon thereafter, the U.S. Environmental Protection Agency announced it would use the linear model for risk assessment. The International Commission of Radiological protection also assumed the LNT as the basis for giving the recommendations for radiological protection.
If the truth was to be told, probably the nuclear industry could have drastically different exposure standards today, and far less fear about exposures to radiation. The resources, world-wide, spent on over-protection could have been better spent on healthcare in under-developed countries.
Saturday, September 10, 2011
Annual average global human exposure to radiation
Radiation is a fact of life. The background radiation (cosmic radiation from space, radiation emitted from the natural radioactive elements present in soil/rocks, like uranium and thorium) contributes significantly to the total population dose. Totally, they contribute about 79 % of the annual average global human exposure to radiation. Out of remaining 21%, 20% is contributed from medical exposures from X-rays and scans and only 1% from all other man-made radiation sources, including nuclear power.
In India, major part (over 98%) of the average annual human exposure is from natural sources, about 1.93% from medical exposures and only about 0.37% from man-made sources. The large difference in medical exposures in the global average and Indian values, is due to enhanced medical care provided in developed countries as compared to India. More scans – more dose.
This information should be made available to the public so that risk from man-made sources is seen in proper perspective. Any activity or industry, which give more benefit than risk are easily accepted by the public. Transparency is the key to public acceptance.
In India, major part (over 98%) of the average annual human exposure is from natural sources, about 1.93% from medical exposures and only about 0.37% from man-made sources. The large difference in medical exposures in the global average and Indian values, is due to enhanced medical care provided in developed countries as compared to India. More scans – more dose.
This information should be made available to the public so that risk from man-made sources is seen in proper perspective. Any activity or industry, which give more benefit than risk are easily accepted by the public. Transparency is the key to public acceptance.
Tuesday, April 5, 2011
Why pick on nuclear power?
Over the last 4 decades, 150 fatalities reported due to radiation exposures. Compared to this, millions and millions of people world-wide are dying on the roads, other industrial accidents, natural calamities, tobacco, pollution, diseases lie AIDS, TB and hunger. On the cigarette pack, it is clearly written that “Tobacco causes caner” or “Tobacco kills”, but still consumption of tobacco is increasing!
Why pick on nuclear? Let media be educated first! The Tsunami which killed thousands is forgotten and the nuclear leak in Fukushima plant in Japan, which may cause some harm to exposed people after 10 to 20 years is making front-page news and breaking news day-after-day! Why? Why people can not see the risks and benefits in proper perspective?
One good reason I can think of is lack of awareness about the radiation, its hazard and benefits amongst the general public, the media, politicians and bureaucrats. Even the so-called well-educated people lack the awareness about radiation. The explosions of the two Atom Bombs over Japan in 1945 have made very bad impact on the perception of anything nuclear in the minds of people. Governments, world-over are simply not able to convince the public about the need of accepting nuclear energy, without any bias, for the benefits in the areas of medicine, industry for power production and agriculture. Definitely, we need nuclear power which is clean and safer than other options.
Why pick on nuclear? Let media be educated first! The Tsunami which killed thousands is forgotten and the nuclear leak in Fukushima plant in Japan, which may cause some harm to exposed people after 10 to 20 years is making front-page news and breaking news day-after-day! Why? Why people can not see the risks and benefits in proper perspective?
One good reason I can think of is lack of awareness about the radiation, its hazard and benefits amongst the general public, the media, politicians and bureaucrats. Even the so-called well-educated people lack the awareness about radiation. The explosions of the two Atom Bombs over Japan in 1945 have made very bad impact on the perception of anything nuclear in the minds of people. Governments, world-over are simply not able to convince the public about the need of accepting nuclear energy, without any bias, for the benefits in the areas of medicine, industry for power production and agriculture. Definitely, we need nuclear power which is clean and safer than other options.
Tuesday, March 29, 2011
Stable iodine prophylaxis
Despite rigorous safety systems in a nuclear reactor, there remains a finite probability that an accident can occur that can lead to the fuel in the core overheating or melting. If such an event were to occur, there is a chance that radioactive fission products may be released to the environment. The potential radiation exposure of the population will be influenced by many parameters such as: the amounts of the radionuclides released, the meteorological conditions affecting the dispersion and deposition of the released radioactive material, human and environmental factors and the effectiveness of any protective actions taken.
Isotopes of iodine particularly I-131, is likely to be important components of the release from a severe accident. Radioactive iodines can give rise to both external exposure and internal exposure (from inhalation and ingestion). Stable iodine prophylaxis is a protective action, for which preparedness arrangements can be made as part of the overall emergency response plan. This step can protect specifically against internal exposure from inhalation, and ingestion of radioiodines by consumption of I-131 contaminated milk/milk products. It should be noted that the term “iodine prophylaxis” refers to the blocking of the uptake of radioiodine by the thyroid gland after nuclear accidents.
The selective and rapid concentration and storage of radioactive iodine in the thyroid gland results in internal radiation exposure of the thyroid, Deterministic effects from thyroid exposure are hypothyroidism and acute thyroiditis. Stochastic effects from thyroid exposure are thyroid cancer and benign thyroid nodules.
As per the WHO document on iodine prophylaxis (update-1999), it recommended that in the management of nuclear reactor accidents, stable iodine prophylaxis for children up to the age of 18 years and for pregnant and lactating women be considered at 10 mGy dose, that is 1/10th of the generic intervention level dose of 100mGy for adults recommended in the IAEA International Basic Safety Standards for Protection against Ionizing Radiation.
The recommended single dosage of stable iodine for prompt administration for adults over 12 years is 130 mg of KI or 170 mg of KIO3, for children (3 to 12 years), the dose recommended is 65mg of KI and 85mg KIO3 and for infants (1 month to 3 years) the dose is 32 mg of KI and 42 mg of KIO3.
Isotopes of iodine particularly I-131, is likely to be important components of the release from a severe accident. Radioactive iodines can give rise to both external exposure and internal exposure (from inhalation and ingestion). Stable iodine prophylaxis is a protective action, for which preparedness arrangements can be made as part of the overall emergency response plan. This step can protect specifically against internal exposure from inhalation, and ingestion of radioiodines by consumption of I-131 contaminated milk/milk products. It should be noted that the term “iodine prophylaxis” refers to the blocking of the uptake of radioiodine by the thyroid gland after nuclear accidents.
The selective and rapid concentration and storage of radioactive iodine in the thyroid gland results in internal radiation exposure of the thyroid, Deterministic effects from thyroid exposure are hypothyroidism and acute thyroiditis. Stochastic effects from thyroid exposure are thyroid cancer and benign thyroid nodules.
As per the WHO document on iodine prophylaxis (update-1999), it recommended that in the management of nuclear reactor accidents, stable iodine prophylaxis for children up to the age of 18 years and for pregnant and lactating women be considered at 10 mGy dose, that is 1/10th of the generic intervention level dose of 100mGy for adults recommended in the IAEA International Basic Safety Standards for Protection against Ionizing Radiation.
The recommended single dosage of stable iodine for prompt administration for adults over 12 years is 130 mg of KI or 170 mg of KIO3, for children (3 to 12 years), the dose recommended is 65mg of KI and 85mg KIO3 and for infants (1 month to 3 years) the dose is 32 mg of KI and 42 mg of KIO3.
Monday, March 28, 2011
Loss-of-Coolant Accident (LOCA) – Nuclear reactors
A loss-of-coolant accident (LOCA) is a mode of failure for a nuclear reactor. If not managed properly and effectively, the results of a LOCA could result in reactor core damage. In every nuclear reactor, a separate Emergency Core Cooling System (ECCS) exists specifically to deal with the situation like LOCA.
Nuclear reactors generate heat internally in the fuel by the fission reaction, neutron with a fissile material uranium-235. This heat is removed by a coolant system to produce steam and is converted into useful electrical power. If this coolant flow is reduced, or lost altogether, the nuclear reactor's emergency shutdown system is designed to stop the fission chain reaction automatically. However, even after reactor shut down, due to radioactive decay of the fission products, the nuclear fuel will continue to generate a significant amount of heat. This decay heat needs to be taken out through secondary cooling system to maintain integrity of the fuel. If all of the independent cooling systems of the ECCS fail to operate as designed due to some reason such as failure of the pumps, this heat can increase the fuel temperature to the point of damaging the fuel and the reactor.
Damage to the reactor containment will result in the radioactive releases from the reactors. Iodine-131 and Xe-133 have half life of 8 days and 5.2 days and hence are detected in the environment in such situations. Depending upon the wind direction and speed, the radioactive isotopes will travel in dispersed form to large distances.
Nuclear reactors generate heat internally in the fuel by the fission reaction, neutron with a fissile material uranium-235. This heat is removed by a coolant system to produce steam and is converted into useful electrical power. If this coolant flow is reduced, or lost altogether, the nuclear reactor's emergency shutdown system is designed to stop the fission chain reaction automatically. However, even after reactor shut down, due to radioactive decay of the fission products, the nuclear fuel will continue to generate a significant amount of heat. This decay heat needs to be taken out through secondary cooling system to maintain integrity of the fuel. If all of the independent cooling systems of the ECCS fail to operate as designed due to some reason such as failure of the pumps, this heat can increase the fuel temperature to the point of damaging the fuel and the reactor.
Damage to the reactor containment will result in the radioactive releases from the reactors. Iodine-131 and Xe-133 have half life of 8 days and 5.2 days and hence are detected in the environment in such situations. Depending upon the wind direction and speed, the radioactive isotopes will travel in dispersed form to large distances.
Monday, March 7, 2011
ICRP Publication 111, 2009
In this document, the International Commission on Radiological Protection (ICRP) provides guidance on “Application of the Commission's Recommendations to the Protection of People Living in Long-term Contaminated Areas after a Nuclear Accident or a Radiation Emergency” for the protection of the people considering effects of: the pathways of human exposure, the types of exposed populations, and the characteristics of exposures. Although, the focus is on radiation protection considerations, the report also recognizes the complexity of post-accident situations, which cannot be managed without addressing all the affected domains of daily life, i.e. environmental, health, economic, social, psychological, cultural, ethical, political, etc. The report explains how the ICRP-103 (2007) Recommendations apply to this type of existing exposure situation, including consideration of the justification and optimization of protection strategies, and the introduction and application of a reference level to drive the optimization process.
The report also considers practical aspects of the implementation of protection strategies, both by authorities and the affected population. The role of radiation monitoring, health surveillance and the management of contaminated foodstuffs and other commodities is described. The Annex summarizes past experience of long term contaminated areas resulting from radiation emergencies and nuclear accidents, including radiological criteria followed in carrying out remediation measures (Extracted for the ICRP site).
The report also considers practical aspects of the implementation of protection strategies, both by authorities and the affected population. The role of radiation monitoring, health surveillance and the management of contaminated foodstuffs and other commodities is described. The Annex summarizes past experience of long term contaminated areas resulting from radiation emergencies and nuclear accidents, including radiological criteria followed in carrying out remediation measures (Extracted for the ICRP site).
Thursday, February 10, 2011
Is India prepared for radiological emergency?
Political situation in Pakistan is very fluid and the terrorist organizations/extremists have stepped up calls for Jihad against India. It is possible that they may even be in position to get their hands on the nuclear weapons in Pakistan and this is going to be matter of deep concern for the security of India. The organizations threaten nuclear war for Kashmir.
In any case, even if nuclear weapons are not used, there is good possibility the use of a radiological dispersion device (RDD) or “dirty” bomb. This is a conventional explosive wrapped in radiological material. Terrorists may use an RDD to disperse radioactive material across a populated area, causing casualties, economic damage and panic. A mere presence of radioactive contamination will create full-blown media coverage and the nuclear program envisaged for the benefit of the country will be in jeopardy.
Is India prepared for such an eventuality, called radiological emergency in any part of the country in terms of trained man power, equipment and logistics?
In any case, even if nuclear weapons are not used, there is good possibility the use of a radiological dispersion device (RDD) or “dirty” bomb. This is a conventional explosive wrapped in radiological material. Terrorists may use an RDD to disperse radioactive material across a populated area, causing casualties, economic damage and panic. A mere presence of radioactive contamination will create full-blown media coverage and the nuclear program envisaged for the benefit of the country will be in jeopardy.
Is India prepared for such an eventuality, called radiological emergency in any part of the country in terms of trained man power, equipment and logistics?
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