Discussion on low level radiation risks in the Bulletin of Atomic Scientists biased

 
 

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May 24, 2012

Needless alarmist views on low dose radiation


 

The Bulletin of Atomic Scientists did not offer an unbiased view

On May 1, this year, The Bulletin of Atomic Scientists published a Special Issue on low level radiation risks. Radiation risk has a bearing on dose limits to radiation workers, guidelines for evacuation of public from areas of contamination and in optimisation of radiation dose in medical radiation procedures.

The effects of high radiation doses are clearly known; at low doses there are uncertainties. The dilemma on the effect of low dose radiation continues.

The Special Issue contains seven articles and an editorial. Rather than offering an unbiased view, the Bulletin tried its best to show that radiation is riskier than what was thought of so far.

Dr Beyea, the Guest Editor reviewed three epidemiological studies including the 15 nation nuclear workers study covering years 1943-2000. They showed some increase in cancer rates at low doses. Each of these studies has infirmities.

Unlike his claim, the 15-nation study did not shock the radiation protection community. Currently, doses to nuclear workers are relatively low.

The present dose limits with the provision that the doses to workers should be As Low As Reasonably Achievable (ALARA) ensure adequate protection effortlessly.

Studies in the High Back Ground Radiation Areas of Kerala showed that there is no cancer risk attributable to radiation. Dr.Bayea did not agree.

“For a more positive view of these types of studies, see Boice et al. (2010),” Dr Beyea suggested. Dr Boice who heads the National Council on Radiation Protection and Measurements did not respond to my e-mail query.

The Bulletin which criticized others who held different views, seldom based it on science. It upbraided the French Academy of Sciences for the relationship of some of its members with the French nuclear industry and medical practice and Electric Power Research Institute with U.S. nuclear industry.

The Bulletin argued that the reports of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) would not say that some risk continues up to zero dose, as the Committee, a product of the United Nations, must be cognizant of national politics in UN countries! Some sort of conspiracy theory!

Protective mechanisms

A paper published in the European Heart Journal (2011) demonstrated that at low doses there might be protective mechanisms at work. In theProceedings of the National Academy of Sciences (2011),researchers showed that cell repair mechanisms were effective in dealing with exposure to low doses of radiation.

A contributor, Dr Colin Hill, University of Southern California skillfully highlighted genomic instability and bystander effects (phenomena which may increase radiation risk), put adaptive response on a low key and ignored the existence of cellular repair mechanisms.

Dr Beyea uncritically accepted the high per capita medical dose (often unwanted) in developed countries as a starting point for millions of people and worried about any exposure to radioactive releases from nuclear accident (Fukushima) as contributing to their delayed cancer risk. He ignored the risks from unwanted medical doses which are often much higher.

The hesitation

Based on one paper, Dr Beyea invoked the so called “supra-linear” concept to argue that low dose radiation is much more dangerous than what was thought of till now; though the authors themselves hesitated to do so.

Dr Hill and Dr Richardson, two contributors, did not respond to the queries of this writer. After protracted correspondence, Dr Beyea wanted me to consider quoting the following from his article.

“It should be noted that all of these cellular effects, including bystander effect, genomic instability, and adaptive response, some of which are thought to have effects working in opposite directions, could already be incorporated into the linear human dose-response curve (Morgan and Sowa, 2009), making the debate much ado about nothing.” The observations claiming enhanced radiation risks had many un-highlighted frailties.

The Guest Editor faced difficulties in compiling the Issue. “Yes, it should be no secret who was asked to contribute to the special issue.” Dr Beyea confided in response to my query.

Dr. John Boice did not have the time, given his new responsibilities. Dr Fred Mettler, Professor Emeritus at the University of New Mexico School of Medicine declined. Dr.Michael Stabin, Adjunct Professor of physics at the Illinois Institute of Technology refused. I was not surprised.

The criticism in this review applies only to the articles, which explain radiobiological concepts. The “sophisticated update” promised by Beyea in the Editorial became one sided. The Bulletin has been less than neutral in its approach; it did not provide the complete picture, particularly on low dose repair related studies.

A reader whose knowledge is confined only to the special issue will not be ready to join the debate armed with a broadbased view. The Issue served to preserve intact, the antinuclear power credentials of the Bulletin!

K.S. PARTHASARATHY

Former Secretary, Atomic Energy Regulatory Board

Nuclear accident risks

                     Your Right To Know

                     Thursday, May 17, 2012

 The link to the article is

http://www.thedailystar.net/newDesign/news-details.php?nid=234424

Nuclear accident risks

K.S.Parthasarathy

Post Fukushima, every one is concerned about nuclear accidents. It added a new dimension. Rightly or wrongly more people characterize nuclear power plants as terribly unsafe. Similar perceptions prevailed over fifty years ago when governments attempted to commercialize nuclear power.
The myth of reactors exploding like nuclear bombs clouds the reality. Often, the public tend to be either pronuclear or antinuclear. Most of the operating nuclear power reactors depend on unforgiving technology. It is a complex technology. The complexity is to ensure safety. Nuclear operators must be eternally vigilant
Suppose a chemical plant handling large quantities of a highly toxic gas or a modern nuclear power plant is about to be involved in a serious accident. If you offer this writer a choice, he will remain near the nuclear power plant. It will not be foolhardy. He is confident that the containment will survive. Even if there is a radioactive release, he knows that he will have enough time to get away! The toxic gas release will kill its victims in seconds!
Can we estimate risks from nuclear reactor accidents? Nuclear industry has clocked over 14,000 reactor years of safe operation.
Fifty years ago, our knowledge about nuclear reactor risks was very scanty. Reactor designs were less robust. Can we ignore the gigantic strides in safety improvements taken by the nuclear industry which provides 13.5% of world's electricity continuously, reliably and exceedingly efficiently?
The US nuclear power industry learnt many lessons from the Three Mile Island accident. These led to making of US nuclear power plants 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 several years
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 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%. In 2009, TMI-1 completed the longest operating run of any light- water reactor in the history of nuclear power worldwide -- 705 days of uninterrupted operation. NRC renewed the licence to operate TMI-1 till 2034.
In USA, with an average annual capacity factor of 91.5%, nuclear power plants are well ahead of coal (7%), natural gas (42%), wind (31%), hydro (27%) and solar (21%).
It was believed that the record performance of all US nuclear power plants post TMI may gradually remove the stigma attached to them because of the TMI accident. But the Fukushima accident is casting its shadow worldwide.
No one appreciates nuclear accident risks quantitatively. Recently, the Organization for Economic Co-operation and Development Nuclear Energy Agency (OECD NEA) published a report titled "Comparing Nuclear Accident Risks with Those from Other Energy Sources." The analysis is meant to help policy makers understand how accident risks are managed at nuclear power plants and illustrate that with a comparison of risks from other energy sources (World Nuclear Association Release September 3, 2010).
The agency collected data on every accident causing five or more immediate deaths in the energy industry between 1969 and 2000. During that period, there were 1,870 such severe accidents worldwide resulting in 81,258 deaths. In the nuclear industry, there was only one accident, the one at the Chernobyl nuclear power plant. Thirty one plant and emergency workers died in the accident. At Fukushima, nobody died due to the nuclear accident. Two workers died due to the tsunami and one worker died in a crane accident during the earthquake.
Possible long-term fatalities due to the accident at Chernobyl continue to be controversial. Based on reports by the World Health Organization, European Commission, International Atomic Energy Agency and Russian authorities, OECD estimated that the Chernobyl accident may eventually cause about 9,000-33,000 deaths over the next 70 years. Possible long-term deaths due to Fukushima accident will be much lower.
Specialists arrived at these numbers based on the controversial Linear No Threshold (LNT) concept which states that any radiation dose however small has a finite effect and it varies linearly with dose. The concept has not been proved irrefutably. It was a practical concept accepted to enforce radiation protection.
The report cautioned that if the same logic is applied, the background radiation to which every one is normally exposed will cause 50 million deaths in the same population in 70 years. "There is no way to definitely confirm these figures for Chernobyl," the report added.
According to OECD, the estimated latent potential death rate for the Chernobyl accident is the same as the immediate deaths resulting from the largest dam failure (the Banquiao/ Simantan failure in China in 1975 claimed 29,924 lives). Many assume potential deaths as real deaths
Premature deaths caused by particulates from fossil fuel generation are thought to be around 288,000 annually worldwide (OECD Environmental outlook).
"Overall, the likelihood of an accident and radiological release is 1,600 times lower than it was when the first reactors were built," the report concluded. This is primarily because of engineering safety improvements among other factors
The report added that more than 2,500 people are killed annually in energy-related severe accidents. Though nuclear power was perceived to be high risk, it caused far fewer deaths than any other energy source.
Public confidence in nuclear operations will increase if trust in the regulators increases. There is also a direct correlation between public trust and awareness of the technology. "Openness and transparency in government decisions about the use of nuclear power and in the licensing process are vital elements in improving public confidence," the OECD report concluded. Unfortunately, in public debates including those by lawmakers, no one highlighted the enhanced safety levels achieved in the operation of nuclear power plants after the Chernobyl and TMI accidents.

The writer is a former Secretary, Atomic Energy Regulatory Board, India.

E-mail: ksparth@yahoo.co.uk

Dirty bombs: May Cost Billions

Posted on May 3, 2012

“Dirty bombs may cost billions in direct and indirect costs”.
Recently, Risk Analysis, a peer reviewed journal published details in a paper titled “Assessment of the Regional Economic Impacts of Catastrophic Events: CGE Analysis of Resource Loss and Behavioral Effects of an RDD Attack Scenario”.
I got particularly interested in this  paper because, one of the authors Dr Paul Slovic, is a veteran in decision research. His articles taught me a few important points in risk communication.
You can access the paper at:
http://onlinelibrary.wiley.com/doi/10.1111/j.1539-6924.2010.01567.x/pdf
For the past many years, it has been fashionable for many to portray vividly the consequences of a dirty bomb attack on a prominent target. Accepting many assumptions, some of the elite faculty and researchers of think tanks maximize the impact.
On February 13, 2004 The Hindustan Times carried a scary news item. Kishore Kuchibhotla and Matthew Mckinzie at Henry L. Stimson Centre, Washington, estimated the possible effects of a dirty bomb. The original report gives many helpful hints to the would-be terrorists!
The scholars chose cobalt -60 as the radioactive material, five pounds of TNT  as the explosive and Lutyen’s Delhi as the location to estimate the impact.
In a day or two, Mr H K Dua, then Editor in Chief of The Tribune requested me to write an OP/ED on the topic. This may be accessed at:
http://www.tribuneindia.com/2004/20040225/edit.htm#7
OR at:
www.dae.gov.in/press/dirtybomb.htm, the official web site of the Department of Atomic Energy, India
I got the impression that these think tanks give very many helpful hints to the would be terrorists!
Since the world is weird and the behaviour of terrorists unpredictable, we must communicate with people during peace time and get them ready to face the challenges posed by terrorism. Ignorance can help to magnify the impact of even minor events involving radioactivity.
I wrote many things about mitigating the consequences  from exploding  a Radiological Dispersal Device (RDD). Now I realize more than ever, tackling radioactive contamination, though important,  is only a minor part of  such a dastardly event

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