RADIATION APPLICATIONS: Looking to the Future
Alan E. Waltar
Ⅰ. Perspective
As documented in reference 1, radiation has already been harnessed in an incredibly wide variety of ways for the benefit of society. Applications to agriculture, medicine, electricity, modern industry, transportation, space exploration, control of terrorism, crime, public protection, arts and sciences, and our environment have made monumental contributions to the quality of life for literally billions of people.
In addition to the tangible improvements in the quality of life that such applications have made, the financial implications have been no less than staggering. In 1995, studies in the United States indicated that nuclear energy (i.e. electricity production) contributed over 90 billion dollars to the U.S. economy, along with 440 thousand jobs. Even more startling, the non-power applications of radiation technology (i.e. those areas listed above exclusive of electricity production) contributed 330 billion dollars to the U.S. economy, along with nearly 4 million jobs. The grand total of the wealth and jobs created by the application of radiation technology in the U.S. was 420 billion dollars and 4.4 million jobs!
I will confess that when I first saw these numbers, I was a bit skeptical. After all, if these numbers were correct it would mean that harnessed radiation technology in the United States created a greater economic impact than General Motors (at that time the largest commercial enterprise in the U.S.), and second only to the entire country’s banking industry. Further, if it were to be translated into a “nuclear nation” it would be larger than the gross domestic product of the entire country of South Korea!
But in checking the results with Roger Bezdek, the author of the studies,(2) I learned that the numbers are actually considerably higher—since Roger pointed out that many companies refused to “admit” their production lines were based on harnessed radiation for fear of negative public reactions that could hurt their sales.
One thing needs to be said regarding the numbers quoted above: they do not reflect only the actual monetary value and jobs created by the industries noted. Rather, they are based on an accepted economic model used extensively for estimating job losses if a major activity, such as a military base, is closed. Indeed, it is not just the number of jobs lost within the example military installation, it also includes the jobs and community funding lost because of the closure of schools, grocery stores, etc. when a sizable portion of the community population is lost. It turns out that a factor of about 2.3 is the accepted number used to multiply the direct jobs lost in converting the value of a particular activity to the actual monetary and jobs values.
That said, there is a crucial need to address unfounded public fear of low-level radiation. We shall address this issue as a separate topic below.
Ⅱ. Unfounded Public Fear of Low-Level Radiation
For well over a half century, a majority of radiation health professionals have generally embraced a philosophy of an ultra-cautious approach to the regulation of radiation exposure. On the face of it, such an approach may seem appropriate. After all, we all know there are deleterious effects of human exposure to high levels of radiation. Hence, it seemed practical, at least in the early days of dealing with this topic, to treat radiation exposure on a very conservative level. On the other hand, more recent research has evolved suggesting either no negative health effects for radiation exposures in the range of global background radiation levels--and even the distinct possibility of beneficial effects in these low ranges. It is important to briefly review the history of this whole matter, how it has led to unfounded public fear, the unfortunate consequences of such fear, and the incentive to move to a more scientific basis for establishing a new approach to regulations.
a. Historical Perspective
During the first several decades after the discovery of radiation, pioneers such as Henri Becquerel, Pierre and Marie Curie, and others dealt with this scientific breakthrough primarily as a matter of curiosity—attempting to understand the basic physics of the governing processes and finding ways to harness this new phenomenon for beneficial use. Very little attention was given to the health effects that might be affecting those engaged in the field.
It was primarily the work of Herman Muller and his colleagues that began raising serious issues regarding the damage to humans that might be associated with radiation exposure. Based on his research on irradiating fruit flies, Dr. Muller concluded that radiation could be damaging not only at high levels, but also at very low levels. During his acceptance speech upon receiving the Nobel Prize for his work in 1946, he emphatically declared that radiation could be damaging at any level. This was the basis for the Linear-No Threshold (LNT) model, which has existed as the basic premise for radiation exposure regulations throughout the world. It means that some damage is incurred down to zero exposure.
But, according to a recent review, (3) Dr. Muller was basing his conclusions on radiation levels considerably higher than what we now consider low level. His irradiation data was in the 250-500 mGy range, well above the roughly 100 mGy level generally considered as low level radiation—and the radiation was delivered over a very short period of time. The global background radiation ranges from about 1mGy per year to over 200 mGy/year in some isolated regions of the world. Interestingly, Dr. Muller was said to be aware of other experiments on the same fruit flies that indicated no harmful effects of radiation at low levels, with at least some indication that there were even beneficial effects at such low levels.
Nonetheless, his declarations (buoyed by the distinction of being awarded a Nobel Prize) went uncontested by the global scientific community. Very premature results from the atomic bomb detonations at Hiroshima and Nagasaki seemed to mesh with his arguments. Then in 1956, the U.S. Academy of Sciences voted to adopt the LNT—giving it the credibility needed to form the basis for current global regulations. But after an extensive review of the history of these events, Calabrese (4,5) pointed out that the National Academy of Sciences did not study the issue in depth; rather they simply adopted the LNT based mainly on a set of pre-conceived beliefs. Whether such accusations are true or not, the LNT then became the uncontested model for all global radiation regulations in existence today.
b. Basis for Current Controversy
As a nuclear engineer, I shall confess that during my early years of study I adopted the LNT as an acceptable basis for establishing conservative levels for low level radiation damage. Even though I knew such low levels were really not harmful, I felt that setting very conservative standards constituted a prudent approach.
But I became more concerned about the consequences of this approach following the 1979 Three Mile Island accident in the U.S., the 1986 Chernobyl accident in Ukraine, and more recently the 2011 Fukushima Daiichi accident in Japan. Public fear (almost pandemonium) created by these accidents not only put the brakes on progress of nuclear technology; such unfounded fear caused an enormous number of actual non-radiation induced fatalities (especially in the aftermath of Fukushima). We need to recall that some 1600 people in Japan actually died as the result of the evacuation measures enforced in Japan, even though prestigious international health effects bodies such as UNSCEAR (6) and ICRP (7) have stated, in writing, that the radiation levels were insufficient to cause ANY life-threatening injuries resulting from radiation. This astounding situation raised an alarm for me that something MUST be done to revisit and revamp existing regulations for low level radiation.
c. A Path toward Resolution
Even before the Chernobyl and Fukushima accidents, I began to question the appropriateness of the LNT. As a trained nuclear engineer, I was taught the three rules of respecting radiation: Time, distance, and shielding. Hence, I’ll admit to a bias that radiation should be respected at any level—even very low levels. Accordingly, I was surprised when I heard lectures from the nuclear medical community reminding me that we all have a very strong immune system. Without such a system, we would all die within hours—since our bodies are constantly attacked with toxins of one kind or another. We all know that our immune system can be strengthened by introducing small levels of toxins into our bodies to provide protection to much larger attacks by the same toxins. Vaccinations are a good example of such medical practice. Taking a small daily dose of aspirin (a “toxin”) is also often used to thin the blood to ward off heart attacks. Routine exercise is always prescribed before attempting to run a marathon. Hence, as it was explained to me, if low levels of radiation did not result in a beneficial effect, it would be an anomaly of medical science.
Wow! What an eye opener!! It was only after hearing this perspective that I found myself open to the possibility that low-level radiation may not be harmful, and it may even be beneficial to the human body.
Since that time I have been devouring medical research that has become available over the past several decades. Whereas there are those still adhering to the LNT model, it seems abundantly clear to me that there is very likely a threshold of radiation levels below which there is either no deleterious effect at all, or even possibly a "hormetic" (beneficial) effect. Since I am not a radiation health professional, I am relying on those who have dedicated their careers to this important field. But I am currently serving as the General Chairman of an American Nuclear Society/Health Physics Society Topical Meeting entitled “Applicability of Radiation-Response Models to Low Dose Protection Standards,” scheduled for September 23-27, 2018 in the United States. This conference is being designed to bring all relevant parties together with the goal of pursuing a path forward to revising low-level radiation standards based on sound science. If successful, the implications to the advancement of radiation technology will have profound impacts.
References:
1. Alan Waltar, RADIATION AND MODERN LIFE: Fulfilling Marie Curie’s Dream, Prometheus Books, 2004.
2. Roger Bezdek, editor, Management Information Services, The Untold Story: The Economic Benefits of Nuclear Technologies (Washington, DC: Management Information Services, Inc., 1996.
3. Jeffry Siegel and Charles Pennington, The Mismeasure of Radiation, Skeptic Magazine, Vol. 20, Number 4, 2015
4. Edward Calabrese, Model Uncertainty via the Integration of Hormesis and LNT as the Default in Cancer Risk Assessment, Dose-Response, October-December 2015:1-5, DOI: 10.1177/1559325815621764.
5. Edward Calabrese, On the origins of the linear no-threshold (LNT) dogma by means of untruths, artful dodges and blind faith, Environ Res. 2015; 142:432-442.
6. UNSCEAR, Report of the United Nations Scientific Committee on the Effects of Atomic Radiation, Fifty-night session (21-15 May 2012)
7. ICRP, Report of ICRP Task Group 84 on Initial Lessons Learned from the Nuclear Power Plant Accident in Japan vis-a-vis the ICRP System of Radiological Protection, ICRP ref 4832-8604-9553, November 22, 2012.