The unfortunate Japanese cities of Hiroshima and Nagasaki provide us with a test lab without peer. Thousands of citizens of all ages were exposed to different amounts of radiation in a very short period of time. From their locations at the time of the blast, their exposures could be determined with relative accuracy. Moreover, they were expected to carry and update their health records. As has been shown, the exposed survivors had unexpectedly longer and healthier lifetimes than did their unexposed cohorts.
But there is now a laboratory for low-level radiation absorbed over a period of twenty years. From 1982 to 1984, about 180 apartment buildings housing 10,000 Taiwanese tenants were built with cobalt-60-contaminated steel (half-life of 5.3 years). Since, as we all know, radiation causes cancer, these unfortunates must be dying like flies.
Well, not exactly. The assessed cancer rate of occupants of the apartments is 3.5 deaths per 100,000 person-years. The average death rate of the general population over the same twenty-year period is 116 persons per 100,000 person-years - resulting in a 97% reduction of fatal cancer.
Have you heard about this story on Headline News? No? Well, maybe no one is interested in reducing his risk of cancer by ninety-seven percent. But just in case you are, you may want to take a look at a paper entitled, "Is Chronic Radiation an Effective Prophylaxis Against Cancer?" [Chen, W.L., Luan, Y.C., et al., "Is Chronic Radiation an Effective Prophylaxis Against Cancer?" Journal of American Physicians and Surgeons, Vol. 9, No. 1, Spring 2004. Taiwanese officials have resisted providing information needed for a first rate epidemiological report, apparently embarrassed that their LNT predictions didn't pan out.]
Showing posts with label Hiroshima. Show all posts
Showing posts with label Hiroshima. Show all posts
Tuesday, April 26, 2016
Tuesday, February 23, 2016
They Lived to Tell About It
The A-bomb survivors are living longer than the controls despite the 400 radiation-induced cancer deaths. - Professor John Cameron, University of Wisconsin School of Medicine
On the morning of August 6, 1945, Hiroshima, Japan, exploded into the first and largest high-level radiation test laboratory in the world. Three days later, because skies over the Kokura Arsenal on the north coast of Kyushu were overcast, Nagasaki became the second. Most victims died from the intense heat or the blast effect, but hundreds were to succumb later to effects of radiation - while thousands of survivors were instantaneously hit with trillions of neutrons and gamma rays.
In the early 1950s, studies of the effects of radiation were needed by the U.S. military and civilian defense authorities because of the threat of nuclear war with the Soviet Union. A joint U.S.-Japan program was initiated to analyze radiation effects on the populations.
Doses to survivors were estimated by their locations at the time of the blasts, with a "health handbook" being kept by each exposed person in which his medical history was meticulously recorded. Of great importance were the potential mutagenic effects (the original concern over "nuclear monsters"), since it was well known that radiation had a mutational effect on fruit flies and other lower organisms and, therefore, was expected to affect humans at high levels. No such consequences were ever found. In fact, not only were the offspring of survivors not negatively affected, but there were benefits that we might now attribute to a hormetic effect of the radiation.
But the primary concern was cancer. Earlier studies of 15,000 people in Great Britain, who had been exposed to upwards of 400 rems in treatment of spinal ailments, had shown a link between high levels of radiation and cancer in a significant percentage of the exposed. The Japanese study, among others, would further refine this relationship to be a 0.018% increase for every absorbed rem. (This is added to the approximately 20% risk of cancer for the average American.) For example a survivor who suffered radiation sickness from an initial pulse of 100 rems would have his or her chance of cancer increased from about 17% to 18.8%. (Remember, this is a dose equal to four times the average lifetime exposure for U.S. residents, occurring in a few seconds or minutes.)
Indeed, there were several hundred excess cancer deaths in Japan among those who received high doses of radiation. [RERF statistics estimate 339 excess cancer deaths (out of 4,687 total cancer deaths) through 1990. John Cameron estimates the projected total at 400.]
And because of the much greater number of persons receiving lesser amounts (typically equivalent to a lifetime of background radiation absorbed in a few seconds) it was feared, on the basis of the newly adopted Linear No-Threshold and collective dose theories, that these survivors were in for even more tragedy. Leukemia would be kicking in in about three to ten years after exposure, with the other cancers occurring within twenty or, at most, thirty years.
But a funny thing happened on the way to the graveyard: The bomb survivors were outliving their unexposed peers. As Dr. Sohei Kondo put it in his 1993 book entitled Health Effects of Low-Level Radiation, "The age-specific rates of death from all causes (observed deaths) [for exposed survivors] in people over sixty years of age were significantly lower than those for people without the health handbook (expected deaths) presumed to be unexposed." [Mentioned earlier in regard to his apoptosis research, Dr. Kondo is professor emeritus of biology, Osaka University and senior researcher, Atomic Energy Research Institute, also in Osaka.] [Kinki University Press, Osaka, 1993, and Medical Physics Publishing, Madison, Wisconsin, 1993. Any serious researcher must have this book. It is the definitive work on the Japanese atomic disaster.]
In short, the exposed had a significantly lower death rate than those who were fortunately out of town for the war-ending fireworks.
Figure 13 demonstrates the classic hormesis-curve shape for death rates of bomb survivors as a function of absorbed dose. [Notes for Figure 13: Death Rates of A-Bomb Survivors in Hiroshima and Nagasaki (1950-85) 1. "Relative Risk is the number of people who have died in a particular exposed cohort compared with (divided by) deaths in a similar group of the general population. 2. These data are for male survivors. 3. Only the acute dose resulting from the blast radiation is considered; external and internal doses by fission products, which would enhance the data, are not included. Source: Mine, M. Okumura, Y., Ichimara, M., Nakamura, T., and Kondo, S. Apparently beneficial effect of low to intermediate doses of A-bomb radiation on human life span. International Journal of Radiation Biology, 58:1035, 1990.]
Up to approximately 70 rems (or cSv), the death rate for exposed persons is lower than unexposed. [Mine et al. Apparently beneficial effect of low to intermediate doses of A-bomb radiation on human life span. International Journal of Radiation Biology, 58:1035, 1990.]
(Not shown on this graph, the relative risk for 325 rems is 1.28.) Note that these data were from forty years after Hiroshima and Nagasaki - concluding well past the established latency time for cancer onset from effects of radiation.
On the morning of August 6, 1945, Hiroshima, Japan, exploded into the first and largest high-level radiation test laboratory in the world. Three days later, because skies over the Kokura Arsenal on the north coast of Kyushu were overcast, Nagasaki became the second. Most victims died from the intense heat or the blast effect, but hundreds were to succumb later to effects of radiation - while thousands of survivors were instantaneously hit with trillions of neutrons and gamma rays.
In the early 1950s, studies of the effects of radiation were needed by the U.S. military and civilian defense authorities because of the threat of nuclear war with the Soviet Union. A joint U.S.-Japan program was initiated to analyze radiation effects on the populations.
Doses to survivors were estimated by their locations at the time of the blasts, with a "health handbook" being kept by each exposed person in which his medical history was meticulously recorded. Of great importance were the potential mutagenic effects (the original concern over "nuclear monsters"), since it was well known that radiation had a mutational effect on fruit flies and other lower organisms and, therefore, was expected to affect humans at high levels. No such consequences were ever found. In fact, not only were the offspring of survivors not negatively affected, but there were benefits that we might now attribute to a hormetic effect of the radiation.
But the primary concern was cancer. Earlier studies of 15,000 people in Great Britain, who had been exposed to upwards of 400 rems in treatment of spinal ailments, had shown a link between high levels of radiation and cancer in a significant percentage of the exposed. The Japanese study, among others, would further refine this relationship to be a 0.018% increase for every absorbed rem. (This is added to the approximately 20% risk of cancer for the average American.) For example a survivor who suffered radiation sickness from an initial pulse of 100 rems would have his or her chance of cancer increased from about 17% to 18.8%. (Remember, this is a dose equal to four times the average lifetime exposure for U.S. residents, occurring in a few seconds or minutes.)
Indeed, there were several hundred excess cancer deaths in Japan among those who received high doses of radiation. [RERF statistics estimate 339 excess cancer deaths (out of 4,687 total cancer deaths) through 1990. John Cameron estimates the projected total at 400.]
And because of the much greater number of persons receiving lesser amounts (typically equivalent to a lifetime of background radiation absorbed in a few seconds) it was feared, on the basis of the newly adopted Linear No-Threshold and collective dose theories, that these survivors were in for even more tragedy. Leukemia would be kicking in in about three to ten years after exposure, with the other cancers occurring within twenty or, at most, thirty years.
But a funny thing happened on the way to the graveyard: The bomb survivors were outliving their unexposed peers. As Dr. Sohei Kondo put it in his 1993 book entitled Health Effects of Low-Level Radiation, "The age-specific rates of death from all causes (observed deaths) [for exposed survivors] in people over sixty years of age were significantly lower than those for people without the health handbook (expected deaths) presumed to be unexposed." [Mentioned earlier in regard to his apoptosis research, Dr. Kondo is professor emeritus of biology, Osaka University and senior researcher, Atomic Energy Research Institute, also in Osaka.] [Kinki University Press, Osaka, 1993, and Medical Physics Publishing, Madison, Wisconsin, 1993. Any serious researcher must have this book. It is the definitive work on the Japanese atomic disaster.]
In short, the exposed had a significantly lower death rate than those who were fortunately out of town for the war-ending fireworks.
Figure 13 demonstrates the classic hormesis-curve shape for death rates of bomb survivors as a function of absorbed dose. [Notes for Figure 13: Death Rates of A-Bomb Survivors in Hiroshima and Nagasaki (1950-85) 1. "Relative Risk is the number of people who have died in a particular exposed cohort compared with (divided by) deaths in a similar group of the general population. 2. These data are for male survivors. 3. Only the acute dose resulting from the blast radiation is considered; external and internal doses by fission products, which would enhance the data, are not included. Source: Mine, M. Okumura, Y., Ichimara, M., Nakamura, T., and Kondo, S. Apparently beneficial effect of low to intermediate doses of A-bomb radiation on human life span. International Journal of Radiation Biology, 58:1035, 1990.]
Up to approximately 70 rems (or cSv), the death rate for exposed persons is lower than unexposed. [Mine et al. Apparently beneficial effect of low to intermediate doses of A-bomb radiation on human life span. International Journal of Radiation Biology, 58:1035, 1990.]
(Not shown on this graph, the relative risk for 325 rems is 1.28.) Note that these data were from forty years after Hiroshima and Nagasaki - concluding well past the established latency time for cancer onset from effects of radiation.
Thursday, February 11, 2016
Rummaging Through the Stacks
Where the radiation level is greater, cancer risk is invariably less. [Nambi and Soman. Further observations on environmental radiation and cancer in India, Health Physics, submitted in 1990, unpublished.]
Presenting the evidence of radiation hormesis has been the most daunting problem faced in writing this book; there is just too much of it. Luckey had more than 2,000 citations in his two books, and he estimates that this was about half of the data available in 1990. [Hormesis with Ionizing Radiation, CRC Press, Boca Raton, 1980; and Radiation Hormesis, CRC Press, Boca Raton, 1991.]
In the fifteen years since then, other researchers have become involved, and their research compounds the problem of "too much" evidence. Until of late there had been only a very few experiments designed to address the radiation hormesis hypothesis, and most of these involved non-vertebrates. [Even more rare are subambient (i.e., less than normal background) radiation experiments, which should show a degradation of biologic function when the target microbes are shielded from cosmic and other background sources. Two such experiments are described in Radiation Hormesis, pp. 211-23.]
The data available - which are the backbone of the argument I'm putting forth [While I have absolutely no reason to distrust the recent test reports that attest to the hormesis phenomenon, there is something very satisfying about examining data taken without any conceivable bias toward "the reverse effect." If there were any bias it was to ignore that which didn't fit the curve.] - are generally one of the following types:
It would be wonderful if there were carefully controlled experimental data on humans for all diseases over the complete radiation dosage range. To optimize the hormesis effect, it would be marvelous to have double-blind studies over long periods of time, with carefully controlled exposures and rates. But we don't have these things.
Presenting the evidence of radiation hormesis has been the most daunting problem faced in writing this book; there is just too much of it. Luckey had more than 2,000 citations in his two books, and he estimates that this was about half of the data available in 1990. [Hormesis with Ionizing Radiation, CRC Press, Boca Raton, 1980; and Radiation Hormesis, CRC Press, Boca Raton, 1991.]
In the fifteen years since then, other researchers have become involved, and their research compounds the problem of "too much" evidence. Until of late there had been only a very few experiments designed to address the radiation hormesis hypothesis, and most of these involved non-vertebrates. [Even more rare are subambient (i.e., less than normal background) radiation experiments, which should show a degradation of biologic function when the target microbes are shielded from cosmic and other background sources. Two such experiments are described in Radiation Hormesis, pp. 211-23.]
The data available - which are the backbone of the argument I'm putting forth [While I have absolutely no reason to distrust the recent test reports that attest to the hormesis phenomenon, there is something very satisfying about examining data taken without any conceivable bias toward "the reverse effect." If there were any bias it was to ignore that which didn't fit the curve.] - are generally one of the following types:
- Animal tests designed to find adverse effects of high levels of ionizing radiation but which happened to take measurements in the low-dose area in the course of the experiment; [According to Luckey, much of the low-dose data - which showed negative correlation of the dose-response relationship - was either ignored, omitted or simply deemed too unimportant to report.]
- Japanese bombing survivors who were within a known distance of A-bomb detonations and whose exposures could be calculated; [There is considerable controversy about exposures, particularly in Hiroshima, with many researchers believing the data analysis understates the radiation dosage. One problem is related to some data still not being available to investigators - even after more than fifty years!]
- Statistical evidence on workers in nuclear power plants and weapons manufacturing facilities; and
- Populations that live in various areas with background radiation up to eighty times the U.S. average.
It would be wonderful if there were carefully controlled experimental data on humans for all diseases over the complete radiation dosage range. To optimize the hormesis effect, it would be marvelous to have double-blind studies over long periods of time, with carefully controlled exposures and rates. But we don't have these things.
Friday, January 8, 2016
Just How Dangerous is Radiation?
In March 1954, sailors onboard the Lucky Dragon were exposed to fallout from a hydrogen bomb test conducted on Bikini atoll. While his two compatriots suffered from radiation sickness, one sailor died the following September. I was a teenager at this time, and yet I can remember a huge amount of news regarding the incident. I suspect it shaped my fear of radiation.
In July 2000, a joint U.S.-Russian Federation report gave as sixty the total number of "criticality" accidents that had occurred in the United States, Russia, France, the United Kingdom, Canada, Argentina and Japan. These accidents occur when too much "fissionable" material comes together for whatever reason and produces for a few moments the same conditions as would be found inside a nuclear reactor. It doesn't cause a "nuclear explosion" but a flash of blue light and a large spike of heat energy. Mr. Harry Daghlian has the unenviable distinction of being the first criticality accident victim in August 1945, during the Manhattan Project. Since then, there have been twenty-one similar deaths, with seven having occurred in the United States.
The most recent were in 1999 when an accident at a Japanese enrichment facility killed two workers. A third worker survived after experiencing severe radiation sickness. I saved the newspaper with that story (prior to the deaths) with the headline "Japanese contain radioactive gas leak" emblazoned across five of six columns at the top of the front page. On the same page there was a notice "Deadly Quake Strikes Mexico/Page 7A." Oh well, I guess earthquake deaths just aren't as fashionable.
Yes, sadly some individuals have died from exposure to radiation. But it is surprising how few, and since there are so few we can account for all or nearly all of them. (This obviously doesn't count the unfortunates who were victims at Hiroshima and Nagasaki, almost all of whom died from blast and heat, but would very likely have died of radiation sickness had they survived the primary causes.)
It is unclear what killed the thirty-one firemen and rescue workers at the Chernobyl disaster. The graphite reactor was in flames (not possible in U.S. power reactors) and was convecting extremely radioactive materials from the core. The probably cause of the firemen's death was heat, since death by radiation generally takes several days to do its work on internal organs. But they, as in the case of the Japanese bomb victims, would very likely have died from radiation.
[I cannot allow Chernobyl to be considered in the same light as other nuclear power facilities. It was built by a Communist government with no concern for the safety of its citizens - as evidenced by the lack of a containment structure to prevent what did happen from happening - and constructed of graphite, rather than water, as a moderator in order that it could be used to produce bomb-grade plutonium. In my opinion, the firemen were murdered by a lack of responsibility on the part of the Soviet government.]
In July 2000, a joint U.S.-Russian Federation report gave as sixty the total number of "criticality" accidents that had occurred in the United States, Russia, France, the United Kingdom, Canada, Argentina and Japan. These accidents occur when too much "fissionable" material comes together for whatever reason and produces for a few moments the same conditions as would be found inside a nuclear reactor. It doesn't cause a "nuclear explosion" but a flash of blue light and a large spike of heat energy. Mr. Harry Daghlian has the unenviable distinction of being the first criticality accident victim in August 1945, during the Manhattan Project. Since then, there have been twenty-one similar deaths, with seven having occurred in the United States.
The most recent were in 1999 when an accident at a Japanese enrichment facility killed two workers. A third worker survived after experiencing severe radiation sickness. I saved the newspaper with that story (prior to the deaths) with the headline "Japanese contain radioactive gas leak" emblazoned across five of six columns at the top of the front page. On the same page there was a notice "Deadly Quake Strikes Mexico/Page 7A." Oh well, I guess earthquake deaths just aren't as fashionable.
Yes, sadly some individuals have died from exposure to radiation. But it is surprising how few, and since there are so few we can account for all or nearly all of them. (This obviously doesn't count the unfortunates who were victims at Hiroshima and Nagasaki, almost all of whom died from blast and heat, but would very likely have died of radiation sickness had they survived the primary causes.)
It is unclear what killed the thirty-one firemen and rescue workers at the Chernobyl disaster. The graphite reactor was in flames (not possible in U.S. power reactors) and was convecting extremely radioactive materials from the core. The probably cause of the firemen's death was heat, since death by radiation generally takes several days to do its work on internal organs. But they, as in the case of the Japanese bomb victims, would very likely have died from radiation.
[I cannot allow Chernobyl to be considered in the same light as other nuclear power facilities. It was built by a Communist government with no concern for the safety of its citizens - as evidenced by the lack of a containment structure to prevent what did happen from happening - and constructed of graphite, rather than water, as a moderator in order that it could be used to produce bomb-grade plutonium. In my opinion, the firemen were murdered by a lack of responsibility on the part of the Soviet government.]
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