Early history of nuclear medicine in India

23 July 2009

The physicists have designed the “hot laboratory” in the institution following the specifications received from USA. They started radioisotope studies in 1951. The institution imported radioisotopes such as P-32, from Harwell, England. Incidentally, Dr Homi Bhabha organized this national conference at the suggestion of Pandit Jawaharlal Nehru who wanted that this opportunity may be used to review what has been done in the field of atomic energy till then. Over 100 specialists attended the meeting. The medical use of radioisotopes grew progressively with the commissioning of Apsara reactor in 1956. Besides diagnostic applications, the specialists started using radioisotopes such as iodine-131 and phosphorous-32 in radiotherapy. During early sixties, test monographs for a few radiopharmaceuticals appeared in international pharmacopoeia and in those of some countries. According to the reports available with the Radiopharmaceuticals Division, Bhabha Atomic Research Centre, the Drug Control Administration in India considered to clear radioisotopes under licence number 720. Uses of reactor- produced radioisotopes increased rapidly. They were in diverse form such as ready-to-use preparations for oral use and for use as injectables; short-lived radioisotope generators to prepare ready-to-use organ imaging agents by intravenous use; cold kits amenable to instantaneous and quantitative incorporation of short-lived radioisotopes for organ imaging etc.
-by Dr K S Parthasarathy
Early History of Nuclear Medicine in India

-by Dr K S Parthasarathy

It appears that the first reference on the medical use of radioisotopes in India has been by Dr Subodh Mitra former Director, Chitaranjan Hospital, Calcutta. In a paper titled “Health Protection, and Biological and Medical Applications of Atomic Energy” (Proceedings of the Conference on development of atomic energy for peaceful purposes in India, Nov 1954), he reviewed the radioisotope- related work in his institution.

The physicists have designed the “hot laboratory” in the institution following the specifications received from USA. They started radioisotope studies in 1951. The institution imported radioisotopes such as P-32, from Harwell, England.

Incidentally, Dr Homi Bhabha organized this national conference at the suggestion of Pandit

Jawaharlal Nehru who wanted that this opportunity may be used to review what has been done in the field of atomic energy till then. Over 100 specialists attended the meeting.

The medical use of radioisotopes grew progressively with the commissioning of Apsara reactor in 1956. Besides diagnostic applications, the specialists started using radioisotopes such as iodine-131 and phosphorous-32 in radiotherapy.

During early sixties, test monographs for a few radiopharmaceuticals appeared in international pharmacopoeia and in those of some countries.
According to the reports available with the Radiopharmaceuticals Division, Bhabha Atomic Research Centre, the Drug Control Administration in India considered to clear radioisotopes under licence number 720.

Uses of reactor- produced radioisotopes increased rapidly. They were in diverse form such as ready-to-use preparations for oral use and for use as injectables; short-lived radioisotope generators to prepare ready-to-use organ imaging agents by intravenous use; cold kits amenable to instantaneous and quantitative incorporation of short-lived radioisotopes for organ imaging etc.

The specialists in this field realized from the very beginning that the production, testing and supply of radiopharmaceuticals must fulfil medicolegal aspects related to the manufacture and use of conventional drugs and radiological safety requirements.

With regulatory control in mind, scientists in the Department of Atomic Energy established a radiopharmaceutical committee and a nuclear medicine committee.

These committees covered all aspects related to the safety of premises, products, patients, workers and the public. Director, BARC set up the Radiopharmaceutical Committee on February 23, 1968. The seven-member committee had Dr V.K.Iya then Head, Isotope Division and, a pioneer in the field as its convener.

The other members of the committee Dr R.S.Mani, Shri T.S.Murthy and Shri N.G.S.Gopal all from Isotope Division were eminently qualified specialists. Since radiopharmaceuticals have to satisfy the general requirements of conventional drugs, the committee had a representative from the Directorate General of Health Services (DGHS), Government of India, as a member.

The committee was to examine the production, practices, controls and the specifications of the radiopharmaceuticals supplied by the Isotope Division and also to consider and recommend the incorporation of radiopharmaceuticals into the Indian Pharmacopoeia.

Simultaneously, Director, BARC set up a five member Nuclear Medicine Committee with members drawn from BARC (Medical Division, Isotope Division, Radiation Medicine Centre), Directorate of Radiation Protection, and the Directorate General of Health Services, Ministry of Health, Government of India, Delhi.

The Committee evaluated the proposals for research, diagnostic and therapeutic uses of radioisotopes, approved a list of doctors trained in radioisotope techniques for established diagnostic and therapeutic procedures, developed procedures for giving standing clearances to established doctors for using standard products without delay and examined applications from every new user and for every new use of medical radioisotopes.

Another function of the nuclear medicine committee was to establish jointly with radiopharmaceutical committee procedures for the release of new products by the Isotope Division, BARC, for medical use.

These Committees were periodically reconstituted. When The Department of Atomic Energy set up the Board of Radiation and Isotope Technology (BRIT), the reconstituted Radiopharmaceutical Committee was brought under it. The Members of the Committee included specialists in nuclear medicine and pharmacy, Commissioner, FDA or his nominee and Drug Controller (India) or his nominee.

These committees met as frequently as necessary. These procedures assured overall though it may be difficult to find direct legal basis for their activities.

In 1977, the Director General of Health Services, Government of India notified that “radiopharmaceuticals” are exempt from the provisions of Chapter IV of the Drugs and Cosmetics Act 1940.

Many considerations must have contributed to this. The mass of radioactive material in any radiopharmaceutical is too trivial to cause any toxic effect; the normally used radioactive materials such as Tc-99m have very short half-lives; it may not be feasible to study them for sufficiently long periods to evaluate the relevant parameters as is done for conventional pharmaceuticals.

During the early sixties and seventies, BARC was the only agency preparing radio pharmaceuticals. In light of interactions with the specialists in BARC, the officials of the Directorate General of Health Services must have realized that granting exemptions will not have serious consequences. DGHS gave exemption nine years after the formation of the Radiopharmaceuticals Committee in which DGHS also had representation.

The Central Government set up the Atomic Energy Regulatory Board (AERB),to enforce safety provisions under the Atomic Energy Act 1962.

AERB reviewed the procedures followed for ensuring safety in the medical use of radioisotopes and retained the set up. In order to provide the much needed legal basis for carrying out medical radiation procedures safely, AERB issued Radiation Surveillance Procedures for Medical Applications of Radiation, 1989 exercising the powers vested under Rule 15 of the Radiation Protection Rules 1971.

As required in the Surveillance procedures, the Board issued several codes; one of them applied to nuclear medicine procedures.

With about 200 physicians licensed to practice nuclear medicine in the country, the facilities available are very modest. Just over 150 hospitals located mainly in cities provide the service.

The field is changing rapidly. The setting up of seven cyclotrons which serve several centres is a notable development.

India needs a ten-fold increase in facilities and man-power to ensure that its population derives the benefits from this advanced field of medicine.▄

Soybean plant adapts itself to Chernobyl

Recently, scientists have reported how soy plant adapted itself to the radioactively contaminated soil near the stricken Chernobyl nuclear power plant.
Dr.K.S.Parthasarathy


Date:23/07/2009 URL: http://www.thehindu.com/thehindu/seta/2009/07/23/stories/2009072350141300.htm Back Sci Tech



Soybean plant adapts itself to Chernobyl

The plants in the contaminated area have a mechanism to protect future progenies by blocking transfer of radio-nuclides to the seeds

Since April 1986, scientists got a unique opportunity to study the impact of radioactive contamination on the plants and animals living near Chernobyl.

The Chernobyl Forum, which is made up of eight specialized agencies of the UN, in its landmark report titled ‘Chernobyl’s Legacy: Health, Environmental and Socio-Economic Impacts,’ made some general remarks on the impact of the accident on the natural environment.
Details emerging

More detailed results of research are emerging now. Researchers from the Slovak Academy of Sciences reported that plants adapted very well to the contaminated environment (Journal of Proteome Research, 2009).

In 2007, they planted ordinary soybean seeds and flaxseeds at a contaminated field in the restricted area about 5 km from the stricken nuclear power plant and at a control field in the same region nearly 100 km away.

The soil in the contaminated area had 163 times more radioactivity (cesium-137) than that in the control area.

The seeds from the contaminated area had less length and width; they weighed about 50 per cent less than those from the control field. Their water-inhibition process was found to be different.

The uptake of radio-nuclides varied significantly within the plant and also between plants.

Though the plant absorbed about 10 per cent of the radioactive contamination, the seeds showed only very low levels of radioactivity. The plants have a mechanism to protect future progenies by blocking transfer of radio-nuclides to the seeds.

Brazil nut, which is well known as the most radioactive food, accumulates radioisotopes of radium. The root system of that tree covers a large area of soil and accumulates radioactivity from the soil.

Nature does not develop any mechanism to arrest the accumulation of radioactivity by the seed. “How do you explain the difference in behaviour between soy plant and Brazil nut tree?”

“I can only speculate that trees might have different mechanisms than plants. Trees are long-living organisms, when compared to crop plants, and thus might not have immediate interest to protect their future progenies from unfavourable environmental conditions”, Dr Martin Hajduch the lead author responded to my e-mail query.
Increased levels

The researchers wanted to develop a model for plant adaptation to increased levels of radiation. They froze the seeds with liquid nitrogen, crushed them to extract the mixture of proteins they contained and ran the seed proteins on 2-Dimensional gel Electrophoresis.

They looked for differences in expression levels of proteins between seeds grown in the contaminated field versus the control field.

The seeds from soy plants grown in contaminated field contained different types and amounts of proteins compared with those from control field. The former plants made many changes to defend themselves and adjusted the levels of several proteins that guard against heavy metals, disease etc.

The researchers found that a certain specific protein which, in test tube studies demonstrated a protective effect against radiation-induced damage, exhibited a 32 per cent higher expression in the seeds from contaminated fields.

The levels of hundreds of proteins which are known for their ability to shuffle other proteins around or tie them up in storage had been lowered.
Why soybean?

Why did they choose soybean plant for the study? “The reason is that soybean is a very important crop worldwide and I worked with it also before”, Dr Hajduch responded to my e-mail query.

“Large percentage of population depends on soybean”, he added.

Do you expect that the mechanisms you observed will be present in plants growing in high background radiation areas such as certain coastal regions in India?

“I would expect it as the mechanisms that plants use to protect their future progenies from harmful effects of radio-contaminated environment should be the same, regardless of the geographical location”, he replied.

Why should we carry out such studies?

“If scientists can understand how plants survive in ultra-hostile environments, it will help them engineer super hearty plants to withstand drought conditions or grow on marginal cropland”, (Aaron Rowe, wired.com, 2009).

K.S. PARTHASARATHY
FORMER SECRETARY, AERB

ksparth@yahoo.co.uk

© Copyright 2000 - 2009 The Hindu

Errors in radiation treatment of cancer

http://www.hinduonnet.com/thehindu/thscrip/print.pl?
file=2009071650111300.htm&date=2009/07/16/&prd=seta&


________________________________________


Errors in radiation treatment of cancer
Several hospitals do not participate in the virtually free audit programme
________________________________________
A well trained clinician can detect exposures involving a 10 per cent or more over-dosage
If the dose delivered is less than 5 per cent of the prescribed amount many cancer cells survive
________________________________________
Everyone knows that Bhabha Atomic Research Centre (BARC) contributes to the strategic areas in the country. Unknown to many, BARC has been, since 1976, rendering a priceless service to radiation therapy centres in India. It ensured that the error in the radiation dose to millions of cancer patients who undergo treatment remained within the clinically acceptable limits of plus or minus 5 per cent of the dose prescribed by radiation oncologists.
Side effects
Doses more than 5 per cent of the prescribed amount, lead to side effects; if less than 5 per cent, many cancer cells survive, causing recurrence. A well trained clinician can detect accidental exposures involving a 10 per cent or more over-dosage, based upon an unusually high incidence of adverse patient reactions (ICRP, 2000).
BARC started a postal dose quality audit programme in 1976, with 9 hospitals, using cobalt-60 machines, participating.
Presently, the Radiation Standards Section (RSS), BARC sends capsules containing a specially prepared thermo-luminescent powder to the hospital. As per instruction, the medical physicist of the hospital exposes them to a specific dose under specified conditions before returning them to BARC. BARC scientists at Trombay estimate the dose accurately.
Most hospitals deliver accurate radiation doses to patients. Some hospitals default. Atomic Energy Regulatory Board (AERB)/BARC has asked hospitals showing unacceptable errors to stop treatment of patients till the issue is resolved.
The service covered over 250 hospitals in India. From the 1990s, 80 per cent of the participants show deviations within acceptable limits compared to 50 to 60 per cent during the earlier period.
Many years ago, in one hospital, the source in its cobalt unit did not move into the treatment position; the patients did not receive any dose for a month, till BARC scientists identified the defect.
Another instance
In another instance, the dose was down by 40 per cent, as an engineer who repaired the unit shortened the length of a cable pulling the source into position. The audit service identified the latter.
During 2007-2008, (48th and 49th batch audit) eight beams showed errors of serious magnitude, ranging from -13.2 per cent to 72.8 per cent. They were due to calculation errors or mistaken irradiation of capsules. A positive deviation leads to under-dosing and inadequate treatment.
We may not know of adverse effects, if any, on any patient, as no one reported them to AERB, though the Atomic Energy (Radiation Protection) Rules, 2004 demand it.
It is appalling to note that several hospitals do not participate in this virtually free service which provides an independent verification of the dose. During February 2006, BARC invited 100 hospitals to the audit programme. Only 33 joined. The number joined and the number of invitations sent for a few batches are as follows: March 2007 (63/142); September 2008(37/98); May 2009 (65/207).
Analysis completed
The analysis for May 2009 is being completed. The number of hospitals with deviations of more than 10 per cent for the other years were 1, 10 and 4. One may feel that the number showing greater deviations are very few.
Little comfort
That is of little comfort for the 40 to 50 patients who may receive improper or inadequate radiation treatment at the defaulting hospitals every day. If there is a -20 per cent deviation, all the patients will get overdosed. An alert oncologist may find something amiss.
The deviations in the institutions which do not cooperate are unknown.
The callous, inexcusable indifference shown by many hospitals in not participating in the audit is at the cost of the patients. Patients may suffer unexpected side effects or receive inadequate treatment due to correctable errors.
Patients getting treated with cobalt machines or accelerators, or their relatives, may ask the head of the radiation therapy department whether the hospital participates in the BARC dose audit programme.
A dilemma
The programme faces a dilemma. Being a routine service, BARC, a research and development agency, may find it difficult to continue the programme routinely.
The stakeholders such as AERB, BARC, Directorate General of Health Services, State Directorates of Medical Education and Health Services must hand over the responsibility of dose audit to an agency, accredited by AERB. BARC can monitor the functioning of this agency. Such an audit by independent agencies is essential to ensure that cancer patients are receiving the correct dose and to avoid gruesome consequences of over-exposures from radiotherapy equipment.
K.S. PARTHASARATHY
FORMER SECRETARY, AERB
( ksparth@yahoo.co.uk)
© Copyright 2000 - 2009 The Hindu

Nuclear medicine: a possible cure to blood cancer

The latest Image of nyuclear medicine showed that nuclear medicine procedures can be used to treat non-Hodgins lymphoma

K.S.Parthasarathy


July 3, 2009


Nuclear medicine: a possible cure to blood cancer
By Dr K. S Parthasarathy
Last month, Dr. A. Lagaru from the Division of Nuclear Medicine at Stanford University Medical Centre and his colleagues won the Society of Nuclear Medicine (SNM) 2009 Image of the Year award in Toronto.
Their poster paper contained an image clearly depicting how radio-immunotherapy can successfully treat non Hodgins Lymphoma (NHL), a potentially fatal form of blood cancer. The US National Cancer Institute estimates that in 2009, 65,980 new cases of NHL will be diagnosed in the US leading to 19,500 deaths.
“Radio-immunotherapy is a form of personalised medicine that combines the cancer fighting ability of radiation therapy with the precise targeting capacity of immunotherapy” (Imaging technology, June 16,2009). It is based on the body’s natural defence system, which protects it from many diseases.
The Stanford group studied two immunotherapy agents Bexxar, which is Iodine-131 based and Zevalin, which is Yttrium-90 based. Iodine-131 and Yttrium-90 are radioactive and emit particulate radiation. The immunotherapy agents home in on the cancerous cells, which become sitting targets for the particulate radiation emitted by Iodine-131 or Yttrium-90 as the case may be. The award-winning image is two sets of before and after Positron Emission Tomography scans of two patients, one treated with Bexxar and the other with Zevalin. Both patients did not show any metabolically active cancer as early as three months after treatment as demonstrated by their PET scans.
A PET scanner uses small amounts of certain radioactive drugs. A special camera that works with a computer provides pictures of the area of the body being imaged. Cancer cells grow and multiply uncontrollably. While doing so, they consume enormous amounts of energy. Basically, this energy comes from burning glucose
Cancer cell metabolise sugar at higher rates than normal cells. Fluoro deoxyglucose (FDG) is a marker for sugar metabolism. It contains Fluorine-18, a positron emitting radionuclide, whose presence will help to trace and locate the sites where FDG molecules get accumulated. Cancerous areas draw higher amounts of FDG, an ideal marker for the disease and its spread. PET scans produce three-dimensional images of the precise location of FDG in the body
“The image of the year was chosen because it shows how molecular therapy can cure non Hodgin’s lymphoma and it provides objective evidence that the patient has been cured”, Dr Henry N, Wagner Jr, a professor of environmental sciences at Johns Hopkins University and past president of the SNM clarified. The Stanford Specialists treated 71 patients. They showed that both the immunotherapy agents are safe and effective in treating non Hodgin’s lymphoma, even in cases where the disease has spread extensively. Twenty four out of 35 patients responded to Bexxar; 28 out of 36 to Zevalin. Taken the two groups together, 27 showed complete response to the drugs. However, in 19 patients the disease progressed in spite of treatment.

Radioactivity in phosphogypsum

The Atomic Energy Regulatory Board has issued a safety directive on the use of phophogypsum in building materials and agriculture. AERB reviewed the radiological safety significance of the material before issuing it. Phosphogypsum contains radioactive materials such as uranium-238 and radium-226.

K.S.Parthasarathy




July 2, 2009


Radioactivity of phosphogypsum to be studied

Phosphogypsum may contain radioactive materials such as uranium-238 and radium-226

The AERB has recently issued a safety directive on the use of phosphogypsum

If you visit any fertilizer factory, you may see large quantities of phosphogypsum (PG) in its premises. It is produced when rock phosphate is treated with sulphuric acid. Each ton of phosphoric acid leaves behind nearly five tons of PG. In many countries, the building industry extensively uses PG in producing cement, wallboard, and other building materials.

Phosphogypsum is not an innocuous material. Besides many heavy elements, it may contain significant quantities of radioactive materials such as uranium-238 and radium-226. Phosphogypsum produced from imported rock phosphates contains typically activity concentrations of U-238 in the range 0.1-0.2 Bq/g and Ra-226 in the range 0.5-1.3 Bq/g. (Bq is a unit of radioactivity. In a radioactive material having a radioactivity of one Bq, one atom disintegrates every sec).

The Atomic Energy Regulatory Board (AERB) has been examining the radiological safety implications of adding phosphogypsum in building and construction materials and in using it in agriculture.

Based on the principles followed internationally, the Board has recently issued a safety directive on the use of phosphogypsum.
Analysing content

The Board directed that all rock phosphate processing industries shall analyze Uranium-238 and Radium-226 content in each imported consignment of rock phosphate as well as in the phosphogypsum produced from its processing and shall report the results to AERB on a quarterly basis. AERB will review this data for a period of about two years for deciding on the frequency of such analysis in future.

AERB decided that its approval is not required for selling phosphogypsum for its use in building and construction materials, if the activity concentration of Ra-226 in it is less than or equal to 1 Bq/g.

If Ra-226 concentration in phosphogypsum is more than one Bq/g, the seller must mix it with other ingredients such that the Ra-226 activity concentration in bulk material is less than or equal to 1.0 Bq/g.

According to the International Atomic Energy Agency (IAEA), at one Bq/g, we need not regulate the material as the radiation doses to persons involved will be insignificant, irrespective of the quantity of material whether it is in its natural state or has been subjected to some form of processing.

AERB stated that its approval is not required for manufacturing and use of phosphogypsum panels or blocks, if they have Ra-226 activity less than 40 kBq/square metre area of any surface of the panels/blocks.

The possible annual increase in radiation dose to a person living in a building made with such panels is sufficiently low to qualify for exemption as per guidelines accepted by the European Commission on Radiation Protection.

The activity levels prescribed by AERB are such that they do not present an unreasonable radiation hazard to anyone.

Further, AERB decided that there need be no restriction for use of phosphogypsum in agricultural applications from the radiological safety considerations.

Twelve fertilizer plants in India presently process rock phosphates imported from countries such as Jordan, China, Morocco, Egypt, Senegal, Togo and others for production of phosphoric acid / fertilizers.
Annual generation

According to Building Materials and Technology Promotion Council, Indian companies generate 4.5 million tonnes of phosphogypsum annually. Over 10 million tonnes gets accumulated at plant sites. In Florida, U.S., alone, more than 900 million tons of PG is stacked in more than 25 stacks. Thirty million tons of PG is produced each year.

AERB received queries from the Ministry of Chemicals and Fertilizers, the Ministry of Agriculture and some of the fertilizer plants regarding restrictions based on radiological safety considerations, if any, on use of phosphogypsum in building and construction materials and in agriculture respectively.

As is the practice evolved by AERB from its inception, the Board issued the directive after a comprehensive and in-depth review of all aspects and after broad consultation with all stakeholders. The inputs needed to arrive at the directive came from extensive research by the scientists from the Bhabha Atomic Research Centre and from the deliberations of specialists in related fields.

K.S. PARTHASARATHY

(Raja Ramanna Fellow, Department of Atomic Energy)

ksparth@yahoo.co.uk

© Copyright 2000 - 2009 The Hindu

Lessons from TMI Accident:US Nuclear

28 April 2009

The US nuclear power industry learnt many lessons from the accident. These led to make US nuclear power plants enviably efficient and safe. In 1980, the average capacity factor (the ratio of electricity produced compared with the maximum electric power a plant can produce, operating at full power all the year around) for US nuclear power reactors was 56.3%; it increased steadily and remained consistently above 90% for the past ten years. Sixteen of the 104 reactors had capacity factors of over 100% in 2008. According to the American Nuclear Society (ANS), the clean up after the accident offered unique technological and radiological challenges. It took 12 years. So far the utility spent nearly US$973 million. The decommissioning team shipped 342 fuel canisters safely for long-term storage at the Idaho National Laboratory. More than 1000 skilled workers carried out safely and successfully the clean up plan developed by a team of specialists. It began in August 1979, with the first shipments of accident-generated lowlevel radiological waste to Richland, Washington. In the cleanup’s closing phases, in 1991, approximately one percent of the fuel and debris remains in the vessel. The team emptied the last remaining water from the TMI-2 reactor in 1991. The cleanup ended in December 1993. The Unit 2 received a license from the NRC to remain as a monitored storage facility, to be decommissioned in 2014.- by Dr K S Parthasarathy

Lessons from TMI Accident: US Nuclear


- by Dr K S Parthasarathy

March 28, 1979 is a day every one in nuclear power industry wants to forget. It was on that fateful day the most serious accident occurred at Unit 2 of the Three Mile Island nuclear power plant in Middletown, Pennsylvania, USA. The accident did not kill or injure any plant worker or member of the public



The unit 2 (900 MWe, Pressurized Water Reactor) was operating at 97% power; some equipment malfunctioned; this, together with certain design-related problems and worker errors led to partial melt down of its core. It shook the confidence of the public.



The clean up measures to mitigate the effects of the accident were very expensive. But the environmental impact of the accident was not high. The US Nuclear Regulatory Commission (NRC) reported that the average radiation dose to 2 million people in the area was about one millirem, compared to the dose due to natural gamma background radiation of about 100 125 millirem for the area; the maximum dose to a person at the site boundary would have been less than 100 millirem.



Several independent groups of respected professionals investigated the accident comprehensively and concluded that in spite of serious damage to the reactor, most of the radionuclides were contained; the actual release had negligible effects on the physical health of individuals or environment. (NucNet release March 23).



According to NRC the accident “brought about sweeping changes involving emergency response planning, reactor operator training, human factors engineering, radiation protection, and many other areas of nuclear power plant operations. It also caused the U.S. Nuclear Regulatory Commission to tighten and heighten its regulatory oversight “(NRC Fact sheet, March 2009).



The Kemeny Commission set up by Jimmy Carter, the then US president, to investigate the accident made comprehensive recommendations.



The US nuclear power industry learnt many lessons from the accident. These led to make US nuclear power plants enviably efficient and safe.



In 1980, the average capacity factor (the ratio of electricity produced compared with the maximum electric power a plant can produce, operating at full power all the year around) for US nuclear power reactors was 56.3%; it increased steadily and remained consistently above 90% for the past ten years. Sixteen of the 104 reactors had capacity factors of over 100% in 2008.



According to the American Nuclear Society (ANS), the clean up after the accident offered unique technological and radiological challenges. It took 12 years. So far the utility spent nearly US$973 million. The decommissioning team shipped 342 fuel canisters safely for long-term storage at the Idaho National Laboratory.



More than 1000 skilled workers carried out safely and successfully the clean up plan developed by a team of specialists. It began in August 1979, with the first shipments of accident-generated lowlevel radiological waste to Richland, Washington. In the cleanup’s closing phases, in 1991, approximately one percent of the fuel and debris remains in the vessel.



The team emptied the last remaining water from the TMI-2 reactor in 1991. The cleanup ended in December 1993. The Unit 2 received a license from the NRC to remain as a monitored storage facility, to be decommissioned in 2014.



TMI-2 cleanup operations produced over 10.6 million litres of accident-generated water that was processed, stored and ultimately evaporated safely.



Early in the cleanup, the team completely severed TMI-2 from any connection to TMI Unit 1. The owners do not anticipate any further use of TMI-2.



Over a dozen major independent health studies of the accident showed no evidence of any abnormal increase of cancers around TMI years after the accident (ANS, 2005). Specialists do not expect any adverse health effect among the populations living in the area is as the radiation doses to the population were negligible.



In June 1996, Harrisburg US District Court Judge Sylvia Rambo dismissed a class action lawsuit alleging that the accident caused health effects.



The National Cancer Institute studied the cancer mortality rates around 52 nuclear power plants including TMI and nine US Department of Energy facilities at the request of US Senator Edward M. Kennedy, chairman of the Senate Committee on Labour and Human Resources.



The study concluded that the survey has produced no evidence that an excess occurrence of cancer has resulted from living near nuclear facilities.



During TMI-2 accident, TMI-1 was shut down for refuelling. It remained shut down till October 1985. TMI-1 received all the benefits from the lessons learnt from the accident at TMI-2.



According to the World Nuclear Association, When TMI-1 restarted, its owners, General Public Utilities pledged that they would operate the plant safely and efficiently; they desired that it would become a leader in the nuclear power industry (WNA, 2001). The plant lives up to their expectations.



The owners of TMI-1 modified the plant and revamped the training and operating procedures in light of the lessons of TMI-2.



Since then, TMI-1 clocked many creditable records. In 1997, TMI-1 completed the longest operating run of any light water reactor in the history of nuclear power worldwide - 616 days and 23 hours of uninterrupted operation. (That run was also the longest at any steam-driven plant in the U.S., including plants powered by fossil fuels.) In October 1998, TMI employees completed three million hours of work without a lost-work day accident. In 2008, it clocked a capacity factor of 106.7%.



The licence to operate TMI-1 expires on April 19, 2014. On January 8, 2008, the utility owners have applied to operate the reactor for an additional 20 years. The NRC has issued the safety evaluation report (NRC release, March 13). Three Mile Island Alert, a nuclear watchdog founded in 1977 has opted not to oppose the plant owner’s (Exelon) application to re-license the plant through 2034.




The record performance of all US nuclear p ower plants post TMI may gradually remove the stigma attached to them because of the TMI accident.

Uranium-in-hair test useless

I wrote the following article in response to of a news-story on "uranium in the hair of children of Faridkot"

Dr K.S.Parthasarathy




SCIENCE & TECHNOLOGY Friday, April 24, 2009, Chandigarh, India
Uranium-in-hair test useless
K.S. Parthasarathy

For the past few weeks, the ‘uranium in hair’ news story from Faridkot has been receiving a lot of media attention.The presence of uranium in hair is nothing new. In USA, several analytical laboratories analyze hair samples and offer advice and treatment. At US $180 per sample, it is a thriving business. Experts argue that the test is useless in the diagnosis of diseases.

Presence of uranium in the hair of children by itself does not mean anything. “I have data on uranium in hair for more than 20,000 persons. I have never seen a single case in which it was clinically significant and affected treatment”, said Dr William Walsh, a specialist in the field responding to my e-mail query.

According to Ronald Kathren, Emeritus Professor, Washington State University, a well-known expert on uranium related fields, background levels of uranium in hair vary highly from person to person and region to region, depending largely on dietary factors.

On June 17, 2008, Aetna, the US agency providing scientific information on health care, asserted that hair analysis has not been proven to be of use in either the diagnosis or treatment of autism.

The American Autism Society concluded thus: “The exact cause of autism spectrum disorders (ASD) is not well understood. …..Currently there are no biological markers for ASD, and diagnosis is based solely on behavioral criteria”.

Pritpal Sigh, head of Baba Farid claimed that “the results were startling”… “around 80 per cent of samples… revealed the presence of uranium in levels that the experts have described as pathological,” he said.

Did they collect for comparison, hair samples from their healthy siblings or from normal children from the regions from which the autistic children came? The study appears to be flawed. My repeated attempts to get the uranium test results from the German Company failed.

Some people made un-substantiated, un-scientific and preposterous claims on the origin of uranium. They attributed the allegedly increased levels to Indian nuclear reactors at 150 km away away, Pakistan’s reactors and winds from Afghanistan. A competent team of scientists from the Department of Atomic Energy is studying the matter. I do not want to prejudice their investigation.

During the 60s, some people in USA argued that uranium in peaches from a region near the Hudson River might have originated from a uranium enrichment plant located across the river.

An enterprising lawyer found that peaches from far off California also contained uranium. Peaches grown in cultivated farms, using fertilizers were more “radioactive” than those grown in virgin fields. Phosphatic fertilizers contain uranium!

Uranium run off from the fields may cause increase in the concentration of uranium in drinking water. This aspect needs closer investigation. Uranium enters body through food and water. Most of it is excreted promptly. Body retains a small portion. A portion of it appears in hair.

We cannot avoid the presence of uranium around us. It is present in rocks, soil, water etc. The first one metre layer of a ten cent piece of land may contain about one kg of uranium. It may be more, or less depending on local geology. Water entering the soil pores carries traces of uranium with it.

Normally, the uranium concentrations in water in India are less than a fraction of a microgramme to a few microgrammes per litre. Scientists have measured moderately high concentrations at a few locations.

Researchers have found that the maximum concentrations of a few hundred to a few thousand microgrmmes per litre in USA, Finland and UK. For uranium, the maximum acceptable concentration of uranium in water is based on its chemical toxicity.

On September 15, 2008, Pritpal Singh sought financial support from Mukesh Ambani. “Dr Carin Smit with her team visited our centre and stayed with us for 15 days and diagnosed the most severe cases and came to the conclusion that mostly kids are highly toxified because of Mercury,” he wrote.

Now Smit claims that uranium is the cause for the health conditions of the children! The investigations on the appropriateness and the legality of some of the treatment practices such as “chelation therapy”, advocated by the foreign team, may open a can of worms.

— The writer is former Secretary, Atomic Energy Regulatory Board

Radiation hits insects

Researchers have found that the populations of insects dwindling at Chernobyl, the World's most sever nuclear accident. Not much systematic work has been reported from the region. Reduction in insect populations can be due to many reasons. More definitive studies are needed to get the final answers.

Dr.K.S.Parthasarathy





Radiation hits insects
K.S. Parthasarathy

















Nearly 23 years ago, on April 26 1986, the most serious accident at Unit 4 of the Chernobyl nuclear power station released large quantities of radioactive materials. Anders P. Moeller and Timothy A. Mousseau, researchers at the University of Paris and South Carolina respectively noted that the ecological consequences of radiation from Chernobyl are poorly known. In the Biology Letters, published on line on March 18, 2009, they claimed reductions in the abundance of insects and spiders linked to radiation from Chernobyl.

Their study covered insect pollinators (bumble-bees and butterflies), predators (dragon flies and spiders) and herbs-feeding insects such as grasshoppers.

Compared to other studies published so far, the present study produced by far the most extensive dataset. The authors carried out two kinds of insect census: point counts covering over 700 sites over three years and line transects.

Since environmental factors other than radiation can affect the abundance of insects, they controlled potentially confounding variables that could affect the relationship between abundance and the level of radiation.

The authors have used scientifically sound methods of census and statistically robust analysis to arrive at their notable conclusions.

Based on other studies they concluded that most radiation around Chernobyl is currently in the topmost soil where most insects live.

“Butterfly eggs, larvae or pupae spent time in the soil layer or vegetation just above. This could negatively affect survival and fecundity and hence abundance. Alternatively, indirect effects of radiation on prey could potentially explain the reduced abundance of spiders and dragonflies, but not the reduced abundance of bumble-bees, butterflies and grasshoppers”, the authors argue.

The authors believe that these results have implications for ecosystems and overall ecosystem functioning. They noted that reduced abundance of pollinators such as bumble-bees and butterflies generally affects plant fecundity and seed set when plant fecundity is pollen limited.

Spiders feed on other insects; if spider population dwindles, it may have impact on the abundance of other insects. “Pollination and predation are considered important ecosystem functioning, suggesting that the Chernobyl region and its surrounding is a perturbed ecosystem”, the authors clarified.

The dwindling population of insects in Chernobyl may very well be due to the rise in populations of insect-eating species such as birds in the exclusion zone around the stricken reactor. Anecdotal evidence suggests that many species sprang up in the absence human habitation. Much more work is needed to get final answers.

Background radiation in certain areas of Kerala and Tamil Nadu is above normal (far too less than that in Chernobyl). I asked Dr Mousseau whether the study of insects and other invertebrates in such high background radiation areas (HBRA) is of any interest. “It would seem to me that this region would likely reveal some very interesting adaptations to radiation that might not have had time to evolve in other regions”, he responded.

. “…it would be important to focus on a few key species that occur in this area and examine survival and reproduction with control sites. Similarly, it would be valuable to examine the community of organisms, especially insects, to determine if species composition changes in a predictable way. Either way, I suspect that this region would be an excellent target for further investigation and my suspicion is that one would be very likely to generate many exciting discoveries of organismal responses to this environmental effect”, he asserted.

Such studies in the high background radiation areas in India may offer invaluable information on the impact of low level radiation on insects, earthworms and such other species.

— The writer is Raja Ramanna Fellow, Department of Atomic Energy

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India's heavy water project comes of age

The Heavy Water Board (HWB), India mastered the technology to produce heavy water indigenously. India is now self sufficient in heavy water and has exported substantial quantities of it. the brief article in the Edit Page of the Deccan Herald reviews the progress made by HWB.

Dr K.S.Parthasarathy





April 6, 2009

IN PERSPECTIVE
India's heavy water project comes of age
By K S Parthasarathy
Techonology for heavy water is being developed. This may lower energy consumption by 60 pc.


It is six decades since Dr Homi Jehangir Bhabha, the architect of nuclear India, initiated moves to make heavy water as a strategic material; he dreamt that India should produce large quantities of it indigenously. He converted his dream into a resolution and got it approved by the Board of Research on Atomic Energy at its second meeting held in Bombay on April 9 and 10, 1948.

“The government should explore the possibilities of using cheap hydroelectric power in India for manufacturing heavy water, on the one hand for our own requirements, and on the other for sale to other countries,” Bhabha pleaded in a covering note to Nehru. The Board’s resolution did not refer to any sale to other countries. So it probably was an afterthought by Bhabha.

In 1954, Dr Bhabha convinced Nehru to set up a fertiliser cum heavy water plant (HWP) at Nangal. The Nangal plant, the largest plant of this type in the world, produced the first drop of heavy water on August 9, 1962. In the next few decades, such drops accumulated into drums at Nangal, Kota, Tuticorin, Thalcher, Baroda, Thal, Hazira and Manuguru.

The rest as they say is history. From dreams to drums, the saga of heavy water production in India is a notable success story.

Heavy water is the coolant and moderator in Pressurised Heavy Water Reactors (PHWR). India is self sufficient in heavy water production, and the Heavy Water Board (HWB) has exported 205 tonnes of heavy water so far.

Heavy water is similar to ordinary water (H2O). But there is a key difference in it. In heavy water, two regular hydrogen atoms are replaced with deuterium, a heavy isotope of hydrogen. Ordinary water contains about 150 parts per million of heavy water. We have to process over 100, ten litre buckets of water to get a cup of heavy water.

India is the largest manufacturer of heavy water in the world, perhaps the only country which has mastered the two processes (hydrogen sulphide-water bi-thermal and ammonia -hydrogen mono-thermal) to produce it. HWB is developing a technology at Baroda using water — ammonia exchange process to operate a heavy water plant independently of fertiliser plants. The cost of energy constitutes 70-80 per cent of the operating cost of HWPs. HWB could reduce over the last decade, specific energy (energy needed to produce a kg of heavy water) consumption by about 36 per cent by systematic energy conservation measures.

It is developing a novel, safe and clean technology to produce heavy water based on hydrogen-water exchange process; specific energy consumption may then be reduced by a further 60 per cent.

Low cost

Chairman and managing director of the Nuclear Power Corporation of India (NPCIL) SK Jain, the main customer of HWB, has acknowledged that the cost of heavy water had come down by 20 per cent in the last few years. “NPCIL could have a surplus of Rs 11,000 crore just on that account,” he said. Plus during 2007-08, all heavy water plants excelled in their performance.

“The capacity utilisation during 2008-09 is expected to touch 125 per cent. HWP Manuguru achieved a capacity utilisation of 137 per cent and the lowest ever specific energy consumption during the year” A L N Rao chairman and chief executive, HWB, informed scientists attending the Heavy Water Day-2009.

HWB has diversified its activities successfully. The board produced many solvents vital to the nuclear industry, and extracted 18O, a valuable isotope for biomedical research, developed technologies to produce sodium metal, to recover uranium from phosphatic fertilisers and to prepare enriched boron.

HWB has faced many challenges (plant operation with fertiliser factories, power scarcity, export controls, poor national industrial infrastructure etc.) in mastering a technology known only to a few advanced countries.

Rao said, “In the functioning of the HWB or of various sub-committees of the board, or of the senior officers at different levels, I have seen team building qualities, challenges being taken up by youngsters and not getting stuck with problems but finding a way out. That’s what has made us move forward.”

Aptly said, the mood is upbeat in HWB.

(The writer is with the Department of Atomic Energy)

Stem cell research gets a shot in the arm

US President Barack Obama removed the barriers to responsible research involving human stem cell research, thereby dispensing with the restrictions former President George W Bush junior introduced. This may provide a shot in the arm for further research in this very useful area.

Dr K.S.Parthasarathy

The article can be located at the following link;
http://www.tribuneindia.com/2009/20090320/science.htm#1




SCIENCE & TECHNOLOGY Friday, March 20, 2009, Chandigarh, India

Stem cell research gets a shot in the arm
By K S Parthasarathy

On March 9, 2009 US President Barack Obama signed an epoch making executive order “removing barriers to responsible scientific research involving human stem cells”. It is indeed a shot in the arm of the beleaguered stem cell researchers.

Stem cells are “blank slate” cells which can divide and renew over long periods. They can develop into a specialised cell, tissue or organ and can effectively serve as a sort of repair system for the body.

Medical specialists believe that stem cells have unlimited potential which can be used to return memory to Alzheimer’s patients, to enable wheel-chair bound patients to walk or to replace damaged skin of patients.

The possibility of miracle cures lies in tweaking the cells to develop into new insulin-producing cells to treat or even cure diabetics, cardio-myocytes to replace damaged heart tissue or cartilage cells to treat arthritis, new nerve cell connections to treat diseases such as Alzheimer’s, Parkinson’s and Amyotrophic lateral sclerosis (ALS), a progressive degenerative disease that attacks the motor neurons in the spinal cord; it leads to debilitating paralysis of limbs and respiration. Appropriately morphed stem cells may replace nerve cells damaged due to spinal injury.

“Advances over the past decade in this promising scientific field have been encouraging, leading to broad agreement in the scientific community that the research should be supported by Federal funds”, Obama wrote in his order.

He conceded that for the past eight years, the authority of the Department of Health and Human Services, including the National Institutes of Health (NIH), to fund and conduct human embryonic stem cell research has been limited by Presidential actions.

On August 9, 2001, Bush decided that federal funds may be awarded for research using human embryonic stem cells if “The derivation process (which begins with the destruction of the embryo) was initiated prior to 9:00 P.M. EDT on August 9, 2001; the stem cells must have been derived from an embryo that was created for reproductive purposes and was no longer needed.”

Mr. Bush did not accept the appeal of several scientists including eighty Nobel laureates urging funding for research on human embryonic stem cells.

On March 9,while welcoming Mr Obama’s decision The New York times noted that Mr. Bush restricted federal financing for embryonic stem cell research to what turned out to be 20 or so stem cell lines that had been created prior to his announcement.

“Those lines are too limited in number, variety and quality to allow the full range of needed research”, the paper clarified.

Obama’s “move ends a long, bleak period in which the moral objections of religious conservatives were allowed to constrain the progress of a medically important science”, the paper observed.

Scientists have to wait till new guidelines governing what research can qualify for federal support are issued by the National Institutes of Health in 120 days as decreed by Mr. Obama

There is another roadblock in the form of Dickey-Wicker amendment (by Representative Jay Dickey, Republican of Arkansas, and Representative Roger Wicker, Republican of Mississippi) which prohibits the use of federal funds to support scientific work that involves the creation of embryos for research purposes or the destruction of human embryos (as happens when stem cells are extracted). Congress has actively renewed that ban each year since 1996.

Scientists who want to create embryos—and extract stem cells — matched to patients with specific diseases, cannot get federal funding till Congress withdraws the amendment. Obama acted swiftly; he left further action to the Congress.

The writer is Raja Ramanna Fellow, Department of Atomic Energy.

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Radioactive contamination in steel: a wake-up call

Frequent appearance of contaminated steel products has been reported from many countries.It appears that three companies made the contaminated steel products from imported scrap.Regulatory bodies have reported that there must be control on scrap imported in to the country.
K.S.Parthasarathy



Date:26/02/2009 URL: http://www.thehindu.com/thehindu/seta/2009/02/26/stories/2009022650061400.htm
________________________________________
Back Sci Tech



Radioactive contamination in steel: a wake-up call

Regulatory authorities have identified Indian steel products contaminated with cobalt-60 in the U.S., Germany, France and Sweden. The events occurred at disturbingly high rates.
“Overall, 123 shipments of contaminated goods have been denied entry to U.S. ports since screening began in 2003, according to Homeland Security data.
Of those, 67 originated in India, 23 came from China and 20 were from Canada” (The Los Angeles Times, November 13, 2008). We cannot ignore this wake-up call.
150 incidents
In the last three years, out of the 500 incidents, involving uncontrolled radiation sources, which the International Atomic Energy Agency (IAEA) came to know, 150 were related to sources found in scrap metal or contaminated goods.
The finding in Germany is attracting more attention. On August 19, last year customs officers identified a container of contaminated stainless steel bars from India on way to Russia. They ordered that the container be put back on the ship immediately and be sent back to India (SPIEGEL ONLINE, February 16).
There were several such findings later; The German Environment Ministry received 19 findings which included radioactive bars, steel cables, chippings and valve housings from 12 states. SPIEGEL reported that a total of 150 tons of contaminated steel has been seized.
Some of it, about 85 tons, according to a reliable source, have been sent back to India. Rest of it remains in Germany pending a decision on its safe disposal.
One of the possible practices is to use the items depending on their radiation levels in fencing or in bridges where the occupancy is less.
Imported metal scrap
After a thorough survey, the Atomic Energy Regulatory Board (AERB) concluded that the steel products in the recent incidents were made out of imported metal scrap which contained radioactive material. India imports more than 80 per cent of stainless steel metal scrap for recycling in the steel industry. Also most of the contaminated material was exported.
The health consequences from these products were negligible, as the radiation levels were low. But the presence of even low radiation levels is not desirable.
We do not have any estimate of the humongous economic losses including loss of business suffered by the industry. In some instances, the defaulters had to ship back the rejected material for safe disposal.
In spite of regulatory control, radioactive sources get lost occasionally. These may be melted along with other metal scrap. The steel products include handle bars, manhole covers, metal straps, steel wires, lift buttons, metal strips used in leather bags etc.
Sources licensed for use in India are unlikely to get into metal scrap, because of regulatory measures in place. However since there were a few instances of loss of control of sources, there is no room for complacency.
Presently, we have no firm assurance that contaminated imported scrap will not enter the country. Several measures including the plan to install radiation monitors at shipping ports through which bulk of the imported scrap metals enter the country must be implemented swiftly.
Precautions
Every importer of metal scrap should obtain a certificate from the exporting country that the scrap is free from radioactivity. A multilayer radiation check system proposed by AERB should be followed to prevent the import and export of radioactive contaminated material.
During this week, over 300 specialists from 62 countries including India are attending a five day International Conference on Control and Management of Inadvertent Radioactive Material in Scrap Metal, organized by the IAEA at Tarragona, Spain. The delegates asserted “that further steps are needed to protect people from radioactive material that can end up in junks and scrap yards,” (IAEA release, Feb 23).
All agencies must wake up before it is too late. Not long ago, explosion of live shells in imported metal scraps led to loss of life in India. Import of scrap laced with high levels of radioactivity is a possibility we must be concerned with.
K.S. PARTHASARATHY
FORMER SECRETARY, AERB
© Copyright 2000 - 2008 The Hindu

Monazite sand does not cause excess cancer incidence

The long awaited study on the cancer incidence among populations living in the high background radiation areas of Kerala has been published in the January 2009 issue of the Health Physics. The study showed that monazite sand does not cause excess cance incidence.

Dr K.S.Parthasarathy







Date:01/01/2009 URL: http://www.thehindu.com/thehindu/seta/2009/01/01/stories/2009010150131600.htm Back Sci Tech



Monazite sand does not cause excess cancer incidence






— Photo: C. Suresh Kumar

Cancer risk: The study found that there is no excess cancer risk to people living in the area of high natural background radiation in Kerala.

Now it is official. In the January 2009 issue of the Health Physics Journal, researchers from the Regional Cancer Centre (RCC), Thiruvananthapuram, and their collaborators have shown that there is no excess cancer risk to people living in the area of high natural background radiation in Kerala from exposure to terrestrial gamma radiation.

The Journal highlighted the importance of the paper by carrying a photo of the beaches in its cover page.
Gamma radiation

The coastal belt of Karunagappally, Kerala, is known for high background radiation (HBR) from thorium-containing monazite sand.

In the coastal panchayats, the median outdoor gamma radiation levels are more than 4 mGy y{+-}{+1} and in certain locations, the levels are as high as 70mGy y {+-}{+1}.(Gy is a unit of radiation dose; mGy is one thousandth of a Gy; the annual gamma radiation level in normal locations is on an average one mGy).

During 1990-97, survey teams collected data on 359,619 subjects in 71,674 households using a standardised questionnaire which covered socio-demographic factors, lifestyle, dietary habits and tobacco and alcohol use.
Follow up study

Based on radiation level measurements, by a method perfected by scientists of the Bhabha Atomic Research Centre, they chose a radiation sub cohort consisting of 173,067 residents and analysed the cancer incidence in the sub cohort, aged 30 to 84y (N=69958 followed up for 10.5 years).

They estimated the cumulative radiation dose to each individual in the age group based on the radiation doses received indoors and outdoors and taking into account how long and where they stayed during the period.

By the end of 2005, they identified 1379 cases of cancer including 30 cases of leukaemia.

The results

Statistical analysis of the data showed no excess cancer risk from exposure to terrestrial gamma radiation.

In site-specific analysis, they did not find any cancer site or leukaemia to be significantly related to cumulative radiation dose.

“Although the statistical power of the study might not be adequate due to the low dose, our cancer incidence study, together with previously reported cancer mortality studies in the HBR area of Yangjiang, China suggests it is unlikely that estimates of risk at low doses are substantially greater than currently believed,” the researchers concluded.

It appears that the researchers were in a hurry to publish the paper. They did not use the complete data but selected four coastal panchayats (Chavara, Neendakara, Panmana and Alappad) which had HBR and two control areas (Oachira and Thevalakkara) which have relatively low natural radiation levels.

They estimated the excess risk as -0.13 Gy{+-}{+1} (95 per cent confidence limit:-0.58, 0.46). The authors pointed out that the upper limit of 95 per cent confidence limit was lower than 0.97, which other researchers got for pooled analysis for nuclear workers from 15 countries (BMJ, 2005) and slightly lower than 0.47 Gy{+-}{+1} reported in the study of atomic bomb survivors in Hiroshima and Nagasaki (Radiation Research, 2007)

Authors highlighted some unique features of their data. Unlike the nuclear workers study, RCC study included smoking habits, an important contributing factor. The estimate of atomic bomb survivors is a sex-averaged estimate for solid cancer unlike the RCC study. The currently accepted radiation risk estimate is mostly based on atomic bomb survivor study.

Regrettably, the researchers did not estimate the substantial contribution of airborne radon and thoron daughters to the individual radiation dose. This may not affect the main conclusion that there is no excess cancer in areas of high natural background radiation.
The limitations

Though the analysis limited to six panchayats cannot be faulted scientifically, they should use complete data including internal dose from all panchayats for a reanalysis to do justice to the project and to examine whether precise radiation risk estimate can be arrived at from this study

Highlighting the negative radiation risk coefficient of -0.13 Gy{+-}{+1}, proponents of those who believe in the beneficial effects of radiation (hormesis theory) may argue that low level radiation is helping to lower cancer risks!

They may not agree that lack of statistical power may be the reason for the negative result.

K.S. PARTHASARATHY
FORMER SECRETARY, AERB

ksparth@yahoo.co.uk

© Copyright 2000 - 2008 The Hindu

Cancer risk not high in radiation workers

The latest issue of the British Journal of Cancer published an epidemiological study of radiation workers in the United Kingdom. It showed that cancer risks to radiation workers increase with dose; the magnitude of the risk estimates are consistent with international consensus. The study will not have any impact on the standards recommended for radiological protection.
Dr.K.S.Parthasarathy


Date:05/02/2009 URL: http://www.thehindu.com/thehindu/seta/2009/02/05/stories/2009020550011300.htm Back Sci Tech

Cancer risk not high for radiation workers

Radiation doses to workers in various professions studied

Cancer incidence among 1,74,541 workers studied

A study published in the latest issue of the British Journal of Cancer (BJC, Vol.100, 2009) by the researchers at the UK Health Protection Agency (HPA) concluded that the risk of developing cancer among radiation workers increases with the dose of ionizing radiation they are exposed to.

This study and the latest research on cancer risks to populations residing in high background radiation areas in Kerala reported in the January 2009 issue of the Health Physics Journal (The Hindu, Jan 1, 2009) are reassuring.

The results of these studies will have no impact on radiological practices, as the observed cancer risks are consistent with the international scientific consensus on radiation protection.

The dose limits to workers are based on such consensus.

The UK study is the third analysis of deaths and cancer incidence among 1,74,541 radiation workers whose occupational histories are maintained in the National Registry for Radiation Workers from 1976. The present study relative to earlier analyses had longer follow-up (to 2001) and cancer registration data and gives more precise information on the risks of occupational radiation exposure. The registry covers virtually all radiation workers from all the main organizations involved in nuclear and related research and industrial sectors in the UK

“This is a continuation of a study started in 1976 and it provides reliable information on the health of people working with ionizing radiation.

The results confirm the cancer risk estimates observed in other studies even though, overall, radiation workers have lower cancer risks than the general population” an HPA release quoted Dr Colin Muirhead from the Health Protection Agency and the lead author of the paper.

This indicates the so called “healthy worker effect”. Usually, workers exhibit overall death rates lower than those of the general population due to the fact that the severely ill and disabled are ordinarily excluded from employment (biology-online.org October 2005).

Scientists who believe in the beneficial effects of radiation may argue that this is an indication of hormesis, a view which will be stoutly rejected by mainstream specialists.

Within the cohort, death from and incidence of both leukaemia excluding chronic myeloid leukaemia and the groupings of all cancers excluding leukaemia (CLL) increased to a statistically significant extent with increasing radiation dose (BJC, January 2009).

It is known that radiation does not induce CLL. The trend in risk was similar to those for the Japanese A-bomb survivors.

The researchers noted that some evidence of an increasing trend with dose in mortality from all circulatory diseases may, at least partly, be due to smoking, a known confounding factor.

So far, specialists have studied the health effects of ionizing radiation on over fifty groups of about two million persons; but the estimates of the long-term health risks from radiation are based largely on studies of the survivors of the atomic bombings at Hiroshima and Nagasaki and of groups exposed for medical reasons.

The dose rates in these instances were high and other exposure conditions were also not similar to those faced by radiation workers.

Radiation workers get exposed to low doses of radiation at relatively low rates.

The UK study is ideal as it represented the typical radiation doses to workers in various professions.

Data collected from employers consist of individual identifiers, factors such as date of birth, gender and industrial classification, and radiation dose histories (BJC, January 2009).

“Continued follow-up of these workers will be valuable in determining whether radiation-associated risks vary over time or by age, and enables the study of specific cancers and causes of death in more detail” HPA argued in a release (HPA release January 7).

In a separate paper in the same issue of the BJC, researchers at the Childhood Cancer Research Group at the University of Oxford and the Health Protection Agency have shown that their study does not support an earlier finding of a raised risk of cancer in children of female radiation workers.

In a subgroup of women who worked with radiation during pregnancy, a weak statistical association was found between maternal radiation work and childhood cancer, but the evidence is limited by the small numbers involved and the result may be due to chance (BJC release January 7, 2009)

Let us hope that HPA does not suffer any resource crunch which may adversely impact on such research.

K. S.PARTHASARATHY
FORMER SECRETARY, AERB

ksparth@yahoo.co.uk

© Copyright 2000 - 2008 The Hindu

Angiography: CT not as effective as conventional

Angiography: CT not as effective as conventional

There is no conclusive evidence that CT angiography is life-saving

Every physician who advertises CT angiography points out that it is painless and takes less time

Risks from radiation exposure are significant when radiation is used for mass screening

Whole-body CT scanning technology fell by the wayside thanks to the uncompromising stand of professional associations and regulatory agencies which highlighted its dangers. But some specialists widely practise cardiac CT tests such as calcium scoring and CT angiography though independent assessments have not proved their effectiveness.

During conventional angiography, the physician threads a thin catheter through the groin artery into the heart, injects a contrast medium and takes x-ray pictures.

These pictures show whether narrowing or blockages in the artery impede the flow of blood. For those with severe blockage, the options are angioplasties possibly with insertion of stents or bypass surgeries.
Risk of bleeding

During cardiac catheterization, there is some risk of bleeding, and a tiny risk for major complications, such as heart attack, stroke, even death.

Every physician who advertises CT angiography points out that it is painless, takes less time and is an attractive option. According to the New York Times, more than 1,000 cardiologists and hospitals installed CT scanners in the U.S. There is undeniable financial incentive to order too many of these tests.
A comparison

The owners argue that the test is cheap, at about $600, paid for by insurers as against $ 4,000 for a cardiac catheterization done at their local hospital.

However, there is no conclusive evidence that CT angiography leads to treatment that saves lives (Health Affairs, Nov/Dec 2008). Conventional angiography remains the gold standard.

Risks from radiation exposure, though small to an individual, are significant when radiation is used for mass screening. There was broad consensus that radiation exposure from CT is of concern.

In India, certain private hospitals advertise CT angiography as very beneficial; none of them refers to radiation risks. Everyone praises the technology. A private hospital used a letter from a member of the faculty of a premier medical research centre to substantiate correlation between CT angiography and conventional angiography!

I sought his reaction to this crude anecdotal approach.

“I routinely write letters to people who have done investigation and what I have done was just to let them know what was the outcome.

“I did not think in my wildest dream that they will utilise it to advertise my letter. I was not aware of it. They are commercial organisations and medicine in a private hospital has become good money making art/business,” he responded to my e-mail.

Pro-screening physicians formed the Screening for Heart Attack Prevention and Education (SHAPE) task force. They want non-invasive imaging of all asymptomatic men (aged 45-75 years) and women (55-75years) except those at very low risk (Archives of Internal Medicine, May 26, 2008).

Evidence of the effectiveness of this recommendation is scanty. These specialists propose the existence of “vulnerable plaques.” The difficulty is that CT cannot identify them.
No clinical utility

“I do not think ‘vulnerable plaque’ has been shown to have any clinical utility,” Dr. Rita Redberg, Professor of Medicine at University of California, San Francisco, responded when I sought her views on promotion of CT by the Indian private hospitals and the SHAPE guidelines.

CT angiography is not as effective as conventional angiography. Those knowledgeable in the field must take the lead in exposing the tendency of hospitals to exploit the “worried well.”

K.S. PARTHASARATHY, FORMER SECRETARY, AERB

KSPARTH@YAHOO.CO.

© Copyright 2000 - 2008 The Hindu

Story of uranium

Story of uranium
K.S. Parthasarathy
AT the tender age of 15 years, Martin Klaproth dropped out of school. He could not pay his fees. He learnt chemistry from the work benches as an apprentice under an apothecary. He struggled for long hours "in the cramped and unhealthy conditions and the tedium of preparing the raw materials and maintaining the hardware for the crushing, grinding, mixing, boiling and distilling that made up his daily routine".
Later, Martin opened his own business. He could spend more time to do research in analytical chemistry. He analysed all types of materials from various countries. He extracted a new element from a piece of rock, some mine-owner gave him. He called it uranium. He announced the discovery at a meeting of the Royal Prussian Academy of Sciences, Berlin, on September 24, 1789.
Uranium remained virtually useless for several decades; small amounts of uranium added to glass before melting gave the glass a pale-yellowish green hue. Some glass specimens contained up to 25 per cent uranium! Geiger counters screamed when it faced the glass surface.
In 1896, Henri Becquerel discovered that uranium is radioactive .In 1934, Enrico Fermi and his coworkers demonstrated beta activity when they bombarded uranium with neutrons. In 1938, Otto Hahn and Leise Meitner discovered nuclear fission and release of fission neutrons.
On December 2, 1942, Fermi and his team achieved the first self-sustaining nuclear chain reaction in a pile of 400 tons of graphite, six tons of uranium metal and 58 tons of uranium oxide, at the University of Chicago. It produced 0.5 watt of thermal power!
Scientists realised the full potential of uranium when they could design, construct and operate nuclear power reactors 168 years after Klaproth discovered it.
India's tryst with uranium started in 1937 when an English man discovered its presence with copper mineral at Mosabani area. There was apparently no followup on this till late 40s.
Dr Homi Bhabha, the architect of nuclear India, knew the value of uranium. "It must be clearly understood that the possession of sufficient quantities of uranium is a sine qua non for the generation of atomic energy….. So far, no large and concentrated deposits of uranium-bearing minerals have been found in India,……It is essential, therefore, that our immediate programme should include an extensive and intense search for sources of uranium. These geological surveys would take at least two years if carried out in any careful and exhaustive way, and it is possible that their result may be negative. In that case India would either have to depend on an agreement with a foreign power for the purchase of her uranium or go in for the much more costly process of extracting uranium from monazite", Dr Bhabha wrote to Pandit Nehru on April 26, 1948.
Dr Bhabha informed Nehru that the Geological Survey of India under Dr. M.S.Krishnan was organizing surveys for thorium and uranium. He insisted that to ensure secrecy, these surveys should be organised directly under the Atomic Energy Commission and Dr. Krishnan "should be allocated full time to this work"
According to Dr K.S. Koppiker, formerly Head, Uranium and Rare Earth Division, BARC, Indian scientists set up in 1949, the first uranium laboratory in Pedder road, Mumbai, at the residence of Dr Bhabha, where Kenilworth building stands today.
Their neighbours complained that they could not suffer the unbearable releases of acid fumes from the laboratory. In July 1954, scientists shifted the lab to an abandoned godown owned by the Bombay Dyeing Company near Siddhi Vinayak Temple.
Uranium is present in trace quantities in soil, rock, water etc. Typical concentration in soil is about 3 ppm (milligramme per kilo gramme).
(K.S. Parthasarathy is Raja Ramanna Fellow, Department of Atomic Energy)

They blazed a trail

The Prime Minister gave away lifetime achievement awards for science and technology for the year 2007 to four scientists while inaugurating the Bhabha centenary celebrations. I wrote the following article about these pioneers in the PTI Feature

Dr K.S.Parthasarathy




19 November 2008


They blazed a trail
By Dr K S Parthasarathy

On 30th October 2008, the Prime Minster, Dr Manmohan Singh, through a video conference from New Delhi, addressed a gathering at Bhabha Atomic Research Centre and launched the birth Centenary Celebration of Dr Homi Bhabha. He honoured Govind Swarup, Suresh L. Kati, S. R. Paranjpe and H.S.Kamath, four distinguished scientists with Lifetime Achievement Awards for the year 2007. The awards, instituted for the first time, consisted of Rs. 10 lakhs each and citations.
Prof. Govind Swarup is conferred the award for "his international recognition and outstanding contributions in the field of radio astronomy and for building ingenious radio telescopes for front line research".
Swarup constructed a 530 m long and 30 m wide parabolic, cylindrical radio telescope of an innovative design at Ooty in South India. Using the method of lunar occultation, it provided for the first time, high-resolution angular data for more than one thousand weak radio sources and independent evidence for the Big Bang model.
In his book Bhabha and his magnificent obsessions, G.Venkataraman described in his inimitable style, the story of the Ooty radio telescope, as told by Swarup.
The idea for the radio telescope came to Swarup in a flash in June 1963 while reading two papers in Nature within two months of his joining the Tata Institute of Fundamental Research. In August 1963, Bhabha grilled him for a couple of hours and gave him the go ahead for the project.
In January 1965, they chose a site for the telescope at Ooty. "Although the Collector of Nilgiris wondered why we were in such a hurry when the life of a star is billions of years, Bhabha got a prompt response from R Venkataraman, then Minister of industries in Tamil Nadu [later to become the President of India]". He allotted the site and electrical connections in a few months.
During 1987-1996, Swarup was principally responsible for the design and construction of the Giant Meter-wave Radio Telescope (GMRT) in Western India. It is the largest radio telescope in the world operating in the frequency range of about 100-1430 MHz. Hundreds of radio astronomers from India and 22 countries use it.
Shri Suresh Kati provided leadership to master the Pressurised Heavy Water Reactor Technology program and to bring it to commercial level in the country despite innumerable constraints.
Kati and his team designed the reactors at the Narora Atomic Power Station which incorporates the best of the safety features to meet international standards. The design of Narora reactors is the standard for 220MWe reactors in the country. He was the Executive Director of the Group which developed the 500 MWe plant which also required many novel systems to be designed and tested prior to their construction.
"The excellent performance of Indian PHWRs is the result of his original contributions in design and is an overwhelming matter of pride for the nation", the citation added.
Kati has strong views on the choice of nuclear technology for India. In the June 2008 issue of the Nuclear Engineering International, he argued that heavy water moderated organic cooled reactors (HWOCR) are the best choice for India as they cost less to construct.
"A 220 MWe PHWR when converted to function as an HWOCR will have a capacity of 270-280 MWe", he asserted.
Shri H. S. Kamath, BARC, Mumbai got recognition for "his outstanding contributions, particularly in the area of Plutonium fuels technology development programs of the Department of Atomic Energy over the last three decades".
During the early eighties, he handled the responsibility to build the Advanced Fuel Fabrication Facility [AFFF] to fabricate MOX fuel for Tarapur Atomic Power Station [TAPS]. "He played a key role in the plant’s conceptual lay out, its detailed engineering, erection of equipment and machinery, safety clearances and commissioning of the plant".
The MOX plant at Tarapur presently fabricates the fuel for Prototype Fast Breeder Reactor [PFBR-500] under construction at Kalpakkam. Kamath and his team at BARC, Trombay manufactured the unique mixed carbide fuel for the Fast Breeder Test Reactor [FBTR] at Kalpakkam; it received international attention due to its excellent performance.
Kamath along with his team is responsible for fabricating fuels for special purpose research reactors and strategic applications. "He is also an acknowledged expert in safety, security and safeguard issues related to special nuclear material", the citation noted.
Shri S.R.Paranjpe contributed significantly to the Fast Reactor Technology programme of the Department of Atomic Energy (DAE). He led the Indian team for the Design and construction of Fast Breeder Test Reactor (FBTR).
Realizing that the steam-generator is a critical component for the success of fast reactor programme, he incorporated them in FBTR. He proposed the use of high plutonium carbide, a unique fuel which saw a burn-up of 155 GWd/t without any failure- a unique feat for any carbide fuel in the world.
He was the architect of the Project report of the first design of the Prototype Fast Breeder Reactor (PFBR). "He built up and nurtured a brilliant team of engineers who designed the PFBR, and have the capability to take on the challenges of advanced breeder reactor designs required for the energy security of India".
"Shri Paranjpe is a multifaceted personality, one who practices what he preaches, a brilliant bridge player and a committed believer in Homeopathy", his long time colleague S K Chande, Vice Chairman, Atomic Energy Regulatory Board reminded me.
Why did these exceptionally brilliant persons choose science and technology for a career, leaving greener pastures behind?
"When I graduated, I could not appear for the Indian Railway Service Commission’s examination, I was under aged; later, I appeared and got selected….I got a Class I post in Central Railway. Just before that I had joined the DAE, I chose DAE as it was a new field and that it would be more challenging. I never regretted the decision". Kati confided
The story was similar for many outstanding persons who joined the DAE. (PTI Feature)

Travails from cobalt-60 contaminated steel

THE HINDU

Date:13/11/2008 URL: http://www.thehindu.com/thehindu/seta/2008/11/13/stories/2008111350171700.htm Back Sci Tech

Travails from cobalt-60 contaminated steel

Contamination of steel is occurring in many countries

On October 22, AFP reported that some French factory workers were exposed to excessive levels of radiation, as they handled lift buttons made using unsafe material contaminated with cobalt-60 from India.

The French Nuclear Safety Authority estimated that 20 out of the 30 workers were exposed to doses ranging from one to three millisievert. The annual dose limit for non-radiation workers is one millisievert, the same as that for the members of the publ ic.

France’s Institute of Radioprotection rightly assured that the health risk to workers is low.
Nuclear event ratings

The French Nuclear Safety Authority rated the incident at Level 2 in the International Nuclear Event Scale (INES) of the International Atomic Energy Agency (IAEA). INES rates nuclear events on a scale of 0 (incident with no safety risk) to 7 (major accident). Events at Levels 1-3 are called “incidents”; Events from 4-7 are termed as “accidents”.

Steel items imported from India to Sweden have also been reported to show faint traces of radioactivity.

The Swedish Radiation Safety Authority considered the levels of cobalt-60 harmless and the components had not been recalled.

Scientists from the Atomic Energy Regulatory Board are investigating the incident.

A few contamination incidents occurred earlier. In 2004, low levels of radioactivity were detected in some of the steel door handles made by another Indian firm.

In this instance, the investigation has shown that it is likely that the manufacturer made door handles out of steel produced in a foundry where imported or domestic metal scrap containing cobalt-60 has been used.

Considering this as a wake up call AERB initiated several preventive measures. AERB has prepared an inventory of all radioactive sources in the country. The inventory is updated periodically.
AERB requirements

AERB allows anyone to handle sources only after ensuring that he/she is adequately trained. AERB requires that the licensees secure the sources adequately in their locations. The probability of an indigenous radioactive source getting into scrap is very low.

AERB officials held meetings with steel manufacturers, All India Induction Furnaces Association, and Engineering Export Promotion Council.

The Board had a series of five workshops with companies carrying out industrial gamma radiography in the country.

The Board advised steel foundry and mill owners to regularly check the scrap for radioactivity by using radiation detection instruments.

Suitable radiation detection instruments are available indigenously or can be imported. Obviously, some companies did not implement AERB’s advice.

Contamination of steel is occurring in many countries. As it happened in U.S.,those Indian companies which suffered are keen to check the scrap with radiation detection instruments.
Slow progress

There were plans to set up radiation monitors at shipping ports through which bulk of the imported scrap metals enter the country. Though the discussions on this programme got started several years ago, the progress has been very slow.

The programme requires coordination from several Central ministries.

Many DAE Installations have been successfully maintaining such radiation monitors at their entry points for the past several decades.

K.S. PARTHASARATHY

Former Secretary, AERB

( ksparth@yahoo.co.uk )