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Warning! Radiation risk Lessons learned the hard way Prof Yash
Pal THIS UNIVERSE
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The recent case of improper disposal of radioactive waste in New Delhi has highlighted the need to be careful in handling such materials, says Roopinder Singh Not only was the nearest town, Pripyat, effected, so were large parts of the western Soviet Union, eastern Europe, western Europe, and northern Europe. There have been other disasters, yet nuclear energy is sought as a major resource for the energy-deficient world. How does a nuclear reactor work? Nuclear power stations use uranium in fission reactions as a fuel to produce energy. They use the heat released during the fission process to generate steam, which turns a turbine to produce electric energy. Of course, the whole process is complex, and operators have to be constantly on the guard to ensure that safety standards are strictly adhered to. Even though it should always be treated with respect, there are many practical applications of radioactivity or radiation. Radioactive materials are involved in the study living organisms, diagnosing and treating diseases, in testing all kinds of industrial objects, including aircraft and ships, and in sterilising medical instruments and food, etc. Radioactive Iodine-131 is used to study the function of the thyroid gland by doctors. It is a tracer, i.e. a radioactive element whose pathway through which a chemical reaction can be followed. Similarly, there are other applications for medical usage. Some universities are also allowed to use radioactive materials, and it was one of these that was the cause of all the trouble in Delhi. A gamma irradiation machine was imported from Canada in the 1970s for use in experiments by chemistry students. It was built by Atomic Energy of Canada Limited. in 1968, had been in disuse since 1985. The machine was auctioned away to scrap dealers on February 26 this year. The scrap went to the Mayapuri, where workers, unaware of its lethal contents, set about dismantling it by removing the protective lead cover, and thus exposing themselves to the radioactive Cobalt-60 isotopes inside it. Although decaying, the radioactive substance was of high intensity and thus the people directly involved in handling the pieces were exposed to high doses of radiation. Severe radiation poisoning was seen in seven persons, one of whom died recently. The other six are also in various hospitals. Initial media speculation centred around a foreign source of the material, a highly likely scenario since 4,000 tonnes of junk metal is imported as scrap in India every day. Later, the police found that the machine had come from the chemistry department of Delhi University. The company that supplied the machine apparently responded to the query with great efficiency and supplied the details of the transaction within a few hours. Officials of the AERB and the National Disaster Management Authority surveyed the largest junk market in India and located the radioactive sources and secured them. Thus ended the latest crisis, which had resulted the in the first the first radiation death in the country. We need to learn our lessons. There is no doubt that a casual attitude towards the disposal of radioactive waste from sources other than nuclear plants has seriously exposed Indians to hazards. The fact is that thousands of tonnes of scrap metals and waste materials are imported into Indian every day and there is a possibility of radioactive material slipping through the ports. Scanners and other safeguards are absolutely necessary to ensure that such hazardous materials are not allowed to slip into our shores. Caution has to be the byword while dealing with materials that can be of immense use on the one hand, and harbingers of death, in case, they are misused.
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In 1993, in Ankara, Turkey, three disused Cobalt-60 teletherapy sources were packaged for re-export to the United States. The sources were not exported immediately, but were stored without the permission of the regulatory authority within the company's premises. In November 1998, the packages were sold as scrap metal. As many as 10 persons were exposed to severe radiation and five of them had to be hospitalised for 45 days. Authorities recovered one source at the scrap yard before it was melted down. The second source, reported to be in one of the packages, has not been recovered to this day. In November 2000, a worker set off a radiation detector at a French nuclear power plant. The cause of the radiation was not in the plant. The worker himself was not contaminated but parts of the metal bracelet of his watch were found to be radioactive. Further analysis revealed that steel pins in the bracelet were contaminated with traces of Cobalt-60. The watches had been imported from Hong Kong, where they had been assembled. The source of the contamination was later traced to a small plant in China that had provided the steel for the bracelet pins. It is believed that a teletherapy head, a device used in radiation treatment of cancer patients had been inadvertently melted down as scrap at this plant. As much as 100 kg of contaminated steel found at the plant in China might never have been discovered and could have been used to make other consumer products. In February 2000, a serious accident in Samut Prakarn, Thailand, resulted in death, injury, and widespread concern. A disused Cobalt-60 teletherapy source was being stored, apparently without knowledge or permission of the regulatory authority, in insecure outdoor premises which was normally used for storing new cars. The accident resulted in radiation injuries to 10 persons. Of these, three died within the first two months, despite medical treatment. Nearly 1,870 individuals living within 100 metres of the junkyard were exposed to the radiation, with many seeking medical attention.
—Source: IAEA |
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THIS UNIVERSE
I am not sure I have the right answer but some thing does occur to me. The flash of a camera is due to relatively high current discharge through the flash tube. In such a discharge lot of ultraviolet radiation is produced. This ultraviolet radiation is mostly absorbed in the coating of the tube to produce the bright light flash. However, it is quite possible that some of this ultraviolet escapes, particularly if the tube is slightly defective. The escaped radiation can ionise the air nearby. Ionised gas can become conducting - at least its resistance is reduced. If this happens near a high tension cable there is a great possibility of discharge, almost like a lightening strike.
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GENEVA: Scientists working on the Big Bang project probing the secrets of the cosmos said on Wednesday their giant particle collider is on course to make unexpected discoveries about the origins and makeup of the universe. Reporting on the progress of the experiment two months into its initial high-power phase, scientists at the CERN research centre said the $10 billion machine was rapidly proving its capacity to advance the frontiers of physics Bad night's sleep can hamper body's insulin use
LONDON: Just one sleepless night can hamper the body's ability to use insulin to process sugar in the bloodstream, according to a study which scientists say might help explain why diabetes is on the rise. Researchers said their findings suggest it may be no coincidence that while sleep duration has shortened in western societies in the past decade there has also been an increase in cases of "insulin resistance" and adult-onset diabetes. Scientist says Bolivar likely died of poison
CARACAS: A U.S. scientist is supporting a theory that has been widely dismissed as a personal obsession of Venezuela's Hugo Chavez: that his hero Simon Bolivar might have died from arsenic poisoning. Venezuela's leftist president rejects the traditional account that Bolivar, a brilliant Venezuelan military tactician who liberated much of South America from centuries of Spanish rule, died of tuberculosis in Colombia in 1830.
— Reuters |
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We are all afraid of radioactivity, yet it plays a vital role in our lives. It is terrible when things go wrong, like they did on April 27, 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which is considered the worst nuclear power plant accident in history. The plant was located in the Ukrainian Soviet Socialist Republic, part of the former Soviet Union. Reactor number four at the Chernobyl plant, had a meltdown, which resulted in a fire that caused radioactive fallout into the atmosphere. 
In its report titled "Lessons Learned the Hard Way," the International Atomic Energy Agency said, "lapses in good practice, human error or lack of knowledge have resulted in serious injuries and deaths." A review of the root causes of these accidents reveals a worrying similarity.
Can the flashgun firing of a camera near a high tension wire lead to electrocution of a person?
