Lifetime Dose

Depiction of a scene from
Voltaire's Candide (1759)
After the reactors in Fukushima exploded in March 2011, residents of the affected areas were advised to keep a journal recording, as best as they could remember, their movements and diet over the weeks just after the disaster. This would help them in the future if they developed health problems or wanted to make claims for compensation. This was an onerous task, but it was no doubt a necessary and excellent idea. In fact, it turns out that it might be a good idea for everyone to maintain such a journal over their lifetime.
Everyone alive today is getting exposed to radiation above what was once natural background – a term which may not mean what it used to because “natural” radon levels are confounded with the radon put into the air because of industrial activities. We live in the fallout from weapons testing and nuclear accidents, live near weapons factories and nuclear fuel processing sites, we spend long hours in airplanes, we get x-rays and other radiological medical procedures, and we face higher exposures to all of these if we are one of thousands of people classified as “radiation workers.”
Dr. Kristen Shrader-Frechette has made the case in a scientific journal for a national radiation dose registry (RDR) for American radiation workers. The number of workers classified as such would surprise most people:

“In Canada, whose population is one tenth that of the United States, there are more than 550,000 radiation workers in more than 80 occupations. These include not only nuclear workers (those employed in commercial nuclear-power generation or by those who build and test nuclear weapons) but also radiation workers who are employed in academic research, food processing, industrial imaging, weld-defect inspection, leak tracing, automobile-steel testing, mineral-deposits discovery, and so on. In Switzerland, radiation workers number 60,000; in South Korea, 65,000. In the United States, 1.5 million radiation workers are occupationally exposed to ionizing radiation each year. Of this number, 300,000 nuclear workers are employed in the commercial nuclear industry.” She adds further in her paper, “… no nation routinely measures cumulative radiation dose and risk from all sources and all exposure classes, even for high-exposure workers.”

Shrader-Frechette’s paper points out the deficiencies of present practices meant to control and track exposures only on the job, and only in limited time frames. A nuclear plant worker who is close to his annual limit for workplace exposure faces a dilemma if his doctor tells him he needs to have a whole-body computed tomography (CT) scan, with an exposure that might add 10 mSv to his workplace exposure. His health might be endangered, and this will put him over the limit, but as far as his employer is concerned, he can still work because the medical exposure is not counted. Incidental and unknown exposures will also not be counted. Not counted is time spent in airplanes at 30,000 feet, time spent in basements with high radon levels, time spent sitting beside people who have recently had radiation therapy, or the cumulative lifetime exposure from x-rays and medical scans.
This concern may sound alarmist and exaggerated, but considering the millions of people affected on and off the job, it would seem wise to apply the precautionary principle. No one can prove that radiation has not contributed to the increasing rates of cancer and endocrine and neurological disorders; whereas there are plenty of research findings that suggest it has been a factor. On both sides of this controversy there is no debate that radiation damages DNA, proteins and cell structures.
It is strange that Shrader-Frechette’s paper includes so many occupations as radiation workers but excludes medical personnel. In recent years, there have been numerous reports of radiological negligence by medical equipment manufacturers and technicians. Medical experts are also sounding the alarm about complacency and sloppiness in radiological treatments within medical institutions. It is common for insufficiently trained staff to be exposed without being aware of the hazards around them. (Supporting sources, with cited text have been placed at the end of this article).
   Someone who begins a nursing career today might want to keep one of those Fukushima journals, or even a dosimeter badge, in order to know twenty years later what her long-term exposure was.
This is not far-fetched because Shrader-Frechette concludes that the Radiation Dose Registry should be extended to “… include medical and occupational radiation exposures for the entire US population. At a fourth stage, all fallout, accident, consumer-product, and other exposures for the US population might be added.” 
Such is the state of radiation risk management in developed nations. In other parts of the world, radiation risks are often higher, but public awareness is non-existent and controls are utterly lacking. The French NGO CRIIAD (Commission de Recherche et d'Information Indépendantes sur la Radioactivité) reports this month on the appalling situation in Niger where French uranium mines have failed to stop radioactive scrap metals from being sold throughout the country or shipped overseas. The report states:

“The scrap metal is contaminated with heavy metal isotopes associated with uranium, such as uranium 238, thorium 230, radium 226, lead 210, and polonium 210. This results in an external irradiation of the population and a risk of internal contamination, depending on how the recycled scrap is used (domestic use is a possibility). Certain of these substances are particularly radiotoxic when ingested or inhaled. The contamination is long-term, considering the long half-life of uranium 238 (4.5 billion years) and radium 226 (1,600 years). The bad practices of Areva’s affiliated companies thus leads to an increased health risk to the population, and beyond to other groups in the event of sales to foreign countries.”

These uranium mines in Niger have had a long, difficult relationship with the locals. When Tom Zoellner was writing his book Uranium, his first attempt to visit the mines was stopped by an attempted attack on the bus he was on. It was then that he learned about the local rebel groups and their resentment about the pollution from the mines and their failure to bring economic development. Yet the French are utterly dependent on the mines for their energy supplies, just as they have other vital interests in Algeria and Mali that that they are being forced to protect quite robustly this year. If Voltaire were alive today he would say, “C’est à ce prix que vous vous chauffez de l’électricité en Europe.”
This scrap metal being resold overseas is a fitting illustration of reaping the whirlwind. The people in Niger handling this scrap may be much more deserving of a proper Radiation Dose Registry, but their dilemma also means that the scrap will go, for example, from Niger to China to your tissue containers or your child’s bicycle basket

And it’s worse than just a couple isolated cases

A Scripps Howard News Service investigation looked at NRC records and the current state of reporting on radioactive materials, turning up numerous flaws in the U.S.'s current system, and finding a wide range of cases in which radioactive materials and products were brought to the U.S.
NRC records show 18,740 documented cases involving radioactive materials in consumer products, in metal intended for consumer products or other public exposure to radioactive material. The U.S. Government Accountability Office estimates there are some 500,000 unaccounted for radioactively contaminated metal objects in the U.S., and the NRC estimates that figure is around is 20 million pounds of contaminated waste. [emphasis added]

   All the more reason for everyone to start wondering about their lifetime cumulative dose of radiation.

Radiological Hazards for Patients and Medical Professionals

Bryant Furlow. “How to Keep Radiation Therapy Safe for Patients.” Oncology Nurse Advisor. December 19, 2011:

For patients, unnecessary procedures (usually imaging procedures) and radiation dosing errors represent the bulk of risk from medical radiation, whereas incidental, unintended radiation exposure is the primary concern for nurses and other health care workers…
Radiotherapeutic advances like intensity-modulated radiation therapy (IMRT), for example, allow escalated radiation dose delivery to tumors while minimizing irradiation of a patient’s healthy, nontarget tissue. However, these advances have come with increased risks when targeting errors occur, such as those caused by patient movement or improper patient setup. IMRT also requires complex three-dimensional (3-D) computed tomography (CT) planning examinations that may frequently involve unnecessarily high radiation doses. Combined with an upward trend in patient radiation doses over recent decades, and improved cancer patient survival times, such considerations raise troubling questions about medically unjustified radiation doses and secondary tumor risks…. Medically unnecessary CT scans are prescribed for up to 20 million American adults and 1 million children each year. A 2007 analysis concluded that up to 2% of cancers diagnosed in the United States may be attributable to CT examinations. The justification of any radiological imaging must always be scrutinized, particularly in pediatric cancer patients, for whom any radiation poses a larger lifetime risk for secondary cancer than for older cancer patients. The availability and sufficiency of alternative imaging modalities that do not involve ionizing radiation, such as magnetic resonance imaging (MRI), should always be considered. Despite numerous calls for electronic medical records (EMRs) to include cumulative radiation dose information, only a handful of US hospitals and medical groups have adopted such systems to date.”

Jane Kiah. “The Importance of Radiation Safety for Healthcare Workers as Well as Patients.” Cathlab Digest Volume 20, Issue 1. January 2012 
About the author: RN, Director of Invasive Services, Baptist Cardiac & Vascular Institute, Miami, Florida; Program Director, Innovations in Cardiac and Vascular Care: Advanced Interventions for Nurses and Technologists, The International Symposium on Endovascular Therapy (ISET):

“One of the root causes of excessive radiation exposure arises from the fact that many in the healthcare field who work with radiation have received only rudimentary radiation training. Whereas interventional radiologists are trained in the safe use of radiation, interventional cardiologists and vascular surgeons, for instance, typically receive minimal radiation training. Because they typically are unfamiliar with all of the sources of radiation exposure, they may know little about risk-reduction and safety strategies. Compounding the problem is that, while a radiologist’s key team member is a radiologic technologist (who also has received radiation safety training), an interventional cardiologist or vascular surgeon’s key team member may be a nurse, who likely has received little to no radiation safety training. That’s not to say that all radiologists employ best radiation safety practices, either. Despite their training, many of them have become complacent.
Additionally, we often use far more radiation than necessary. In the United States, there is an increased emphasis on ensuring the highest quality images, which means more radiation. That’s not the case in Europe and Japan, where safety is more highly valued. The ideal dose is the least amount of radiation possible to produce an acceptable image. A good operator knows how to produce good images without excess radiation.”


Bruno Chareyron (nuclear physics engineer) (editor). Almoustapha Alhacen, Anne Hollard. 1,600 Tons of Scrap Metals Missing from AREVA Facilities in Niger. Published by CRIIRAD, AGHIR IN MAN and AAM (Les Amis d’Aghirin’Man). January 17, 2013.

Kristin Shrader-Frechette. “Trimming Exposure Data, Putting Radiation Workers at Risk: Improving Disclosure and Consent Through a National Radiation Dose-Registry.” American Journal of Public Health 97, no. 10, 1782-1786. October 2007.

Jonathan Tirone and Andrew MacAskill. “Nuclear Risks at Bed, Bath & Beyond Show Dangers of Scrap.” Bloomberg News. March 20, 2012.

Hiroko Nakata. “Bridgestone to recall nearly 10,000 Jobno bicycles with radioactive baskets.” The Japan Times. April 20, 2012.

Walt Bogdanich and Kristina Rebelo. “A Pinpoint Beam Strays Invisibly, Harming Instead of Healing.” The New York Times. December 28, 2010. 

C'est à ce prix que vous mangez du sucre en Europe.
It is at this price that you eat sugar in Europe.
Words of the black slave of Suriname in Voltaire’s Candide, chapter 19. 1759.

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