Medicine For People!

August 2016

Atmospheric CO2

Radiation Danger: The Surprising Truth

Why I Prefer Nonfiction

When I read a really good novel, I find myself writing down certain passages that I want to remember. Good stories, be they fictional or not, can beautifully transmit great truths about this world of reality which we all share. You saw this in our last newsletter, with Carlos Castaneda's reminder that we are forever being hurled into strange new worlds.

Fantasy writers such as Tolkien and Rowling build great detailed worlds of the imagination, with forces of good and forces of evil. The dangers in these imaginary worlds are enormous. Often, just one person or force is presented as being so dangerous, they threaten all life. This makes for an exciting story. So do the movies so popular today that show the entire world being threatened by one single force—a virus, an alien invader, a nuclear holocaust, erupting volcanoes, or perhaps an earthquake. But in the nonfiction world we call reality, even the most dangerous threats out there turn out to be... often not that bad. They don't make very exciting news stories unless someone uses their imagination to amplify the dangers and play on our fears.

That may be why Google is developing an enhancement to virtual reality.

The world that fascinates me is the nonfictional one. This world, the one we probe with our minds and our measuring tools. For what, after all, are our microscopes and telescopes, our oscilloscopes and laboratory instruments, our mathematics, but measuring tools? We accept these tools as accurate only when they provide a measurement that we can all see and agree on. Through them we learn of the hidden systems that raise our blood pressure or cause infections—or abort cancerous cells. In this real world there are also trolls, evil creatures such as you might find in a book of fiction. In this real world we find that they are sometimes part of ourselves, as the Darth Vader of fiction was really part of the hero Luke.

If you decide to become a doctor, then your education lands you in the midst of chemistry, physics, and mathematics. For me, these were lonely pursuits, quiet evenings spent at my desk with a textbook, pencil, paper and my desk lamp, working out the solutions to carefully posed and sequenced problems that moved those universes of reality from the page into my head. To me, these shared, nonfictional worlds outshine fictional worlds almost all of the time.

I was allowed a little time for literature, art, music, and philosophy. I particularly liked the Stoics. But medical school colored my views there as well. The philosopher may ask "what can we know? How can we agree on the nature of reality?" Medical school simplifies the answers. You can try to build this imaginary world or that, this theory or that, but nature always bats last. The patient will tell you if they feel better or not. They will walk or not. They will live or not. Medicine is not about contemplating your own navel. It is a service to others on their own terms and on nature's terms, or it is nothing. (Which can mean contemplating the patient's navel, sometimes.)

The best physicians and the best scientists follow ideas humbly. Imagine Einstein asking himself, "what if time is not the regular drum beat we imagine? What if the length of a yard can vary from place to place?" His imagination was powerful, but he made it subservient to reality. Without such humility, we could not have sent people to the moon, and much of our current technology would be impossible.

My own imagination is not that great but I have learned through a lifetime of experience to always question what I think. Nature speaks to us every day.  When we do not listen we drift into error, be it medicine, plumbing, childcare or politics.

Let me give you an example of learning from nature. Let me show you the dull reality behind our fear of being exposed to radiation.

Taiwan, April 1985

This story begins with a dentist setting up an office in his apartments in the Minsheng Villas on Longjiang Road in downtown Taipei. To be sure that his x-ray machine does not project radiation into adjacent rooms, two inspectors come as usual to be sure all is in order. After setting up their equipment, they check baseline levels. To their astonishment, even with the x-ray machine unplugged they measure unacceptably high levels of radiation.

They report it to Taiwan's Atomic Energy Council. This agency discovers that the walls in the Minsheng Villas are themselves radioactive. They quietly investigate. The concrete walls contain radioactive steel rebar. They trace this to a steel smelter and find that the Hsin Lung Steel Company incorporated radioactive cobalt into a batch of steel used to make the rebar used in the walls of the Minsheng Villas.[1],[2]

Taiwan's Atomic Energy Council covers up the crime. They tell the dentist his equipment is faulty and cannot be used.

Songshan district, Taiwan, Summer 1992

Years later, an electrical utility worker brings his Geiger counter home from work to familiarize himself with the instrument. To his surprise, it shows high levels of radiation emanating from the concrete walls of his apartment. This time the cat escapes the bag. Subsequent investigation confirms that the walls of his apartment building are radioactive as well. You guessed it: they contain rebar from the same batch as was used in the Minsheng Villas.

As the agency had known all along, the culprit was cobalt-60. The facts come out. From 1982 to 1984, about 1700 apartment units and shops were constructed using the radioactive rebar.[3] Finally, public health workers and epidemiologists are called. But to their surprise, they found that these apartment dwellers had a lower rate of death from cancer than the general public.[4]

The authors gave a reason for this lower rate: a phenomenon called radiation hormesis.[5] There is evidence that low doses of radiation actually stimulate DNA repair mechanisms and thus reduce radiation damage rates to levels lower than they would otherwise be, resulting in less cancer and greater longevity.

Unfortunately, there is an evil troll in the above story: the regulatory agency. Penetrate the pay walls behind which copyright owners hide too much scientific literature, check the details, and you find that 8 of the 14 authors of Chen's study are or were associated with the same agency that covered up the original contamination. This is not the kind of scientific impartiality one has a right to expect. Other investigators looking at the same incident did not find that building apartment buildings with contaminated rebar provided any benefit to the residents of those buildings.

Still, the reality is surprising. The most recent study available surveyed 6200 of these apartment dwellers in 2005. [6] Each had been exposed, every day for an average of 18 years, to over 10 times the usual radiation we get from cosmic rays, background radiation, and medical imaging. As all Taiwanese eventually die of something, and 45% die of cancer, we would expect that about 2800 of these residents will eventually succumb to cancer. But this was not an old folks' home and most of these people were relatively young. Some 117 died of cancer between 1983 and 2005, not statistically different from what one would expect were there not radioactive cobalt-60 in the walls.

A caveat: radiation damage is discernible at submicroscopic levels in many of these people. And if you look in particular at leukemia, six people died from it, a significant difference from the expected five in this age group.

We tend to imagine the gremlins of radiation as much more dangerous and deadly than they actually are. If someone proposed to you that we recycle nuclear waste into commercial steel products to be used in residential construction, wouldn't you guess that the carnage would be much greater than it actually turns out to be? I know I would have.

How Dangerous is Radiation?

To set the stage: the dangers of radioactivity have been apparent since the death of Marie Curie, the discoverer of radium. Yet there are also benefits.

A personal digression: When I was about 10 years old, afflicted with growth retardation and a mysterious anemia, my doctors withdrew several ounces of blood, made them radioactive, and put them back into my circulatory system. Every week or so they drew a little blood to see how long my red cells lived. At no point did I glow in the dark. They successfully arrived at the correct diagnosis and treatment, and I am as reasonably healthy as any 71-year-old person has a right to be.

In undergraduate school I worked with radioactive materials in a research laboratory. Our studies helped elucidate how digitalis works when we treat heart failure. And of course in medical practice we use radioactive materials to ascertain whether or not cancer has spread, to find hidden fractures, to study the function of the brain and the thyroid gland, to treat thyroid and other cancers, and much else.

Take home lesson: Exposure to radiation is not always dangerous.

It's All in the Dose

Let me give you an example now from a medical encounter. Jane has symptoms of an overactive thyroid, so I suggest a radioactive iodine uptake and scan. I explain to her that when she is injected with radioactive iodine, her thyroid gland rapidly scavenges all of it, and very little will wind up in other parts of her body. And in any event, the scanner is extremely sensitive and only minute quantities of the radioactive material will need to be injected.

Jane agrees to this, and the scan shows that she is hyperthyroid. The treatment alternatives include another injection of radioactive iodine, but this time a large dose. Jane asks why this will be safer than surgery. I explain that her thyroid gland will again rapidly scavenge it, sparing the rest of her body, and once her gland has greedily scavenged it all, there will be so much radioactivity in the gland that all her thyroid tissue will be destroyed. And destroyed thyroid cells cannot cause cancer.

Jane wisely decides to go ahead.

Take home: Dose and details matter.

Albert Stevens

Albert Stevens

Albert Stevens painted houses for a living.[7] As World War II drew to a close, he had significant stomach trouble and consulted physicians at the University of California in San Francisco. He appeared to have terminal cancer of the stomach, and his doctors did not think he would live much beyond his age of 58.

During the 1930s advanced, more scientists and technicians were exposed to hitherto unknown radioactive materials.  To ascertain the safety measures appropriate to those materials, physicians including Dr. Joseph Hamilton started to look at their medical effects. Here is a Wikipedia picture of him drinking radioactive sodium in 1939.

In 1945, his tasks at UCSF's radiology department included a study on the health effects of radioactive plutonium.

The study had advanced to from rats to humans, trying to understand what constituted a safe dose and at what level it became a dangerous dose. As a physician, I am embarrassed to tell you that they did not tell the people chosen for their experiments what they were doing. They knew it would be difficult to obtain consent. They justified this by choosing only people already close to death from terminal illness.

Albert Stevens was the first of their 18 subjects. Now, among the various measures of radiation, physicians use a unit called the Sievert[8] to measure radiation doses. About 4 Sieverts, given all at once, is enough to kill most people. Mr. Stevens was injected with a quantity of plutonium great enough to give him a subsequent lifetime dose of 64 Sieverts.

However, Mr. Stevens survived another 20 years and died of heart disease. We can credit his survival to two facts:

One: Subsequent surgery showed that his "cancer" was in fact a stomach ulcer.

Two: They injected him with two forms of plutonium, one with a half-life of 24,000 years and one with a half-life of 88 years. So the plutonium released its radioactivity slowly, something we are better able to tolerate.

Mr. Stevens was never told that he did not have cancer. Every year for 20 years, the plutonium in his body gave him 60 times the radiation exposure permitted for nuclear power plant workers. He died at the age of 79 of heart disease, and could well have survived longer had he not been injected with radioactive plutonium. (Dr. Hamilton, by the way, lived only to the age of 49. He died of radiation-induced leukemia.)

Normal Radiation Doses

Most of us get about 3 milliSieverts (thousandths of a Sievert) of radiation each year from the air (mostly radon which comes out of the ground), food and water (natural radiation and potassium, carbon, etc.), cosmic rays, and other sources. When you average in the radiation from CT scans and other medical procedures and scans, most Americans get another 3 milliSieverts radiation each year, for a total of 6 milliSieverts.[9] Let us call this our annual baseline radiation.

So if radiation were a pill, and each pill contained one year's baseline (in other words, 6 milliSieverts = 1 unit):

Dose

Baseline radiation units

US annual average radiation exposure

1

1962 US fallout from atmospheric testing of over 500 atomic bombs

.02

Current US fallout from that atmospheric testing

.005

Average dose to people living within 10 miles of the Three Mile Island accident[10]

.01

Maximum dose to immediate neighbors of the Three Mile Island accident

0.25

Single full-body CT scan

3

20-year career as commercial aircraft cabin crew

5

Maximum annual allowed dose for US nuclear power workers

10

Maximum dose to residential neighbors of the Fukushima power plant during tsunami aftermath

12

6 months' service on the International Space Station

13

Lowest 1-year dose clearly linked to increased cancer risk

20

Maximum allowable for US astronauts, lifetime

165

Fatal if taken all at once

650

Human record for long-term survival with long-term exposure (Albert Stevens)[11]

10,000

Note: These numbers are approximate. Background radiation includes both natural and man-made and varies from 3 mSv worldwide to about 4 mSv in Japan and over 6 mSv in the U.S. due to our higher use of medical radiation procedures.

Some Perspective

To put the above figures in perspective, here are the actual damages we're currently experiencing from global warming:

  • DARA International estimates the current death rate from global warming to be 400,000 adults and children per year, mainly from communicable disease and disruption of agriculture which is decreasing food supply in marginal economies.[12]
  • The World Health Organization reports 70,000 excess deaths in Europe alone during the 2003 heat wave,[13] as well as 40,000 more deaths per year from weather-related natural disasters. These figures represent "only a subset of the possible health impacts, and assuming continued economic growth and health progress," WHO "concluded that climate change is expected to cause approximately 250 000 additional deaths per year between 2030 and 2050; 38 000 due to heat exposure in elderly people, 48 000 due to diarrhoea, 60 000 due to malaria, and 95 000 due to childhood undernutrition."[14]
  • A 2009 report in The Guardian reported 300,000 deaths per year at that time and estimated this figure would rise to half a million per year in 2030.[15]

Radiation and Nature

Only around the time of the Second World War did the general public become aware of atoms, isotopes, and radiation, and this may be why we can so easily regard them as something alien. Radon from the ground, cosmic rays from the sky, the minuscule radioactivity of our food—all this is not easily observed. What we can see with our own eyes are x-ray machines, nuclear power plants, and atomic bombs, all so obviously artificial.

The public and our regulatory agencies both accept the idea that any amount of radiation is harmful. But there are numerous reasons to doubt this. For example, Kerala in Southeast India has unusually high background radiation because of radioactive thorium in the soil. Residents are exposed to double the usual background radiation, and in some places on the coast to as much as 30 times usual background radiation. Yet no increase in cancer incidence was identifiable in a 10-year study of about 70,000 Keralans.[16]

The Oncology journal reports that it just has not been possible to demonstrate any increased risk of cancer at exposures less than 100 milliSieverts,[17] which is about 15 times the U.S. background radiation and double what you are allowed to be exposed to if you work in a nuclear power plant.

Over 30 years ago, a biochemist named T. D. Luckey, whose major research was in living systems, obtained use of a special underground facility at the Argonne National Laboratory in Chicago. This facility was designed to eliminate all outside radiation. It was accessed through a four-ton door and lined with over 8 inches of steel to reduce cosmic rays. Dr. Luckey wanted to find out what happened to living systems in the absence of radiation, and chose to study single-celled organisms called paramecia. At great expense (one of the ingredients of their liquid environment cost $28,000) he created a very low-radiation home for these paramecia. The results? These paramecia grew and multiplied slowly. Only when he provided them with external radiation did they attain normal size and fertility.[18]

Other studies in animals and in cell culture indicate that very low doses of radiation stimulate certain protective processes such as DNA repair, immune competence, elimination of precancerous cells, elimination of free radicals, and other phenomena. [19],[20]

The National Institute for Occupational Safety and Health tracks medical outcomes of workers in the nuclear industry. One of their studies covered some 63,000 people working in the nuclear industry, some working since the 1960s and many with asbestos exposure. [21] Cancer deaths occurred at a rate 7% greater than expected. Despite this, the group as a whole had a 4% lower death rate. A Canadian study showed the same thing: slightly higher death rate from cancer, but overall better longevity.[22]

We know that natural radiation was higher at earlier stages of our planetary evolution. Most of our biologic systems, including radiation damage repair, developed in an environment that had up to twice the natural background radiation as today.[23] In summary, studies of low doses of radiation exposure hint that we may be optimized for a slightly higher background radiation then we live in today. In my view, both our national attitudes and U.S. policy regarding radiation exposure are excessively conservative and will at some point need to be modified to fit our observations of reality.

We still have much to learn.

______________________________________________

Thanks to Jody Bowers for significant editorial assistance.

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Endnotes

[1] Grano SA. EnvironmentalGovernance in Taiwan:A New Generation of Activists and Stakeholders. London: Routledge, 2015: p. 65.

[2] Arrigo LG, Puleston G. "The Environmental Movement in Taiwan after 2000: Advances and Dilemmas." In: Fell D, Kloter H, Bi-Yu C, eds. What has Changed? Taiwan Before and After the Change in Ruling Parties. Research Unit on Taiwanese Culture and Literature, Ruhr University, Bochum: Vol. 4. 2006. Harrassowitz Verlag: Wiesbaden; pp.165-186

[3] https://en.wikipedia.org/wiki/List_of_civilian_radiation_accidents#1980s

[4] Chen WL, Luan YC, Shieh MC, Chen ST, Kung HT, Soong KL, et al. Effects of cobalt-60 exposure on health of Taiwan residents suggest new approach needed in radiation protection. Dose Response. 2007;5:63–75. doi: 10.2203/dose-response.06-105.Chen.

[5] https://en.wikipedia.org/wiki/Radiation_hormesis

[6] Hwang S-L, Hwang J-S, Yang Y-T, Hsieh WA, Chang T-C, Guo H-R, et al. Estimates of relative risks for cancers in a population after prolonged low-dose-rate radiation exposure: a follow-up assessment from 1983 to 2005. Radiation Research. 2009;170 (2): 143–8.

[7]

[8] https://en.wikipedia.org/wiki/Sievert

[9] https://www.mun.ca/biology/scarr/Radiation_definitions.html

[10] https://en.wikipedia.org/wiki/Sievert#Dose_examples

[11] ttps://en.wikipedia.org/wiki/Albert_Stevens

[12] DARA. Climate vulnerability monitor: the cold calculus of a hot planet. http://daraint.org/wp-content/uploads/2012/09/EXECUTIVE-AND-TECHNICAL-SUMMARY.pdf

[13] WHO. Climate change and health fact sheet. http://www.who.int/mediacentre/factsheets/fs266/en/

[14] WHO. Quantitative risk assessment of the effects of climate change on selected causes of death, 2030s and 2050s. Geneva: World Health Organization, 2014.

[15] Vidal J. "Global warming causes 300,000 deaths a year, says Kofi Annan thinktank." The Guardian, May 29, 2009. https://www.theguardian.com/environment/2009/may/29/1

[16] Nair RR, Rajan B, Akiba S, Jayalekshmi P, Nair MK, Gangadharan P, et al. Background radiation and cancer incidence in Kerala, India-Karanagappally cohort study. Health Phys. 2009 Jan;96(1):55-66. doi: 10.1097/01.HP.0000327646.54923.11.

[17] Janjan N. The risks of undiagnosed cancer vs the theoretical risks of radiation exposure. Oncology. March 14, 2014.

http://www.cancernetwork.com/oncology-journal/risks-undiagnosed-cancer-vs-theoretical-risks-radiation-exposure

[18] Luckey, TD.Radiation hormesis: the good, the bad, and the ugly. Dose Response. 2006 Sep 27;4(3):169-90. doi: 10.2203/dose-response.06-102.Luckey.

[19] Aurengo A, Averbeck D, Bonnin A, Le Guen B, Masse R, Monier R, et al. Dose-effect relationships and estimation of the carcinogenic effects of low doses of ionizing radiation. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.126.1681&rep=rep1&type=pdf

[20] Neumaier T, Swenson J, Pham C, Polyzos A, Lo AT, Yang P, et al. Evidence for formation of DNA repair centers and dose-response nonlinearity in human cells. PNAS. January 10, 2012;109(2):443–448.

[21] Schubauer-Berigan MK, Macievic GV, Utterback DF, Tseng C-Y, Flora J, et al. An epidemiologic study of mortality and radiation-related risk of cancer among workers at the Idaho National Engineering and Environmental Laboratory (INEEL), a U.S. Department of Energy Facility. http://www.cdc.gov/niosh/oerp/pdfs/INEEL-10-15-04.pdf

[22] Zablotska LB, Lane RSD, Thompson PA. A reanalysis of cancer mortality in Canadian nuclear workers (1956–1994) based on revised exposure and cohort data. Brit J Cancer. 2014;110, 214–223 | doi: 10.1038/bjc.2013.592

[23] Karam PA, Leslie SA. The evolution of the earth's background radiation level over geologic time. www.irpa.net/irpa9/cdrom/VOL.2/V2_69.PDF

 

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Medicine for People! is published by Douwe Rienstra, MD at Port Townsend, Washington.