Low-level Radiation material

Ionizing Radiation Exposure and Cancer (abstract of JAMA article, Mar 1991).
It is well known that ionizing radiation can cause cancer, especially leukemia, thyroid, lung and breast cancer, in heavily exposed persons. But in this study, workers at the Oak Ridge National Laboratory were not highly exposed; their average exposures were hardly above usual background levels of ionizing radiation. The death rates of these workers for cancers and for all causes combined was below the national average. However, their leukemia death rate was slightly elevated (63% above average); this finding is significant because leukemia is one of the sentinel cancers caused by ionizing radiation. Of greater significance is that workers who were exposed to slightly greater levels of ionizing radiation showed higher death rates from all cancers combined as well as from leukemia compared to less exposed workers and the risk of cancer increased with the amount of radiation received at the work place. Furthermore, the radiation induced cancers did not appear until 35 years or more after the laboratory was first opened suggesting that there is a long delay between first exposures to low level radiation and the manifestation of excess cancer deaths.
The emergence in this study of a pattern of increasing cancer death rates with increasing low level radiation exposure, the stronger association with radiation received decades ago than with recent doses, the specificity of the association with cancer rather than with other causes of death and the observation of an overall excess of leukemia deaths compared with the general population, all are consistent with a real low dose radiation effect. This raises concern that our results may be applicable to other populations exposed to low level radiation. It is crucial that epidemiological studies of other occupationally exposed populations be conducted to address the ultimate implications of this study.
[ Wing, S., Shy, C., Wood, J., et. al. Mortality among workers at Oak Ridge National Laboratory, Evidence of radiation effects in follow-up through 1984. Journal of the American Medical Association, 265(11): 1397-1402 (March 20, 1991)]

Risk Estimates of Low-Level Ionizing Radiation. by Prof Wolfgang Kohnlein (Director of The Institute For Radiation Biology, University of Munster, Germany)
Premature evaluations of the delayed effects of radiation among the Japanese survivors, as well as transference to humans of radiation effects in animals, lead to strongly held optimistic convictions. For decades, any challenge to these tenets based on extrapolations by epidemiologic studies among populations with occupational and environmental exposures, were received with enmity and rejection. Nevertheless, optimistic expectations had to be scaled back continuously as the appearance of long delayed excess cancer cases among the Japanese survivor population.
Time is now running out for the risk estimates supporting the official interagency policy that low-level ionizing radiation is "harmless". The reason for this is that during the "harmless" era there were many unnecessary and avoidable exposures to low-level radiation.
Newer studies reported 0.05 Sv as the doubling dose for leukaemia, lung cancer and other cancer forms while the official estimates in inter-agency reports are still well over 1 Sv.

Chronic Low-Dose Radioactive Exposure: False Alarm or Public Health Hazard ? by Prof Wolfgang Kohnlein
Whenever an ionising track traverses a nucleus of a mammalian cell, there is always a chance that it will cause a carcinogenic lesion and that the lesion will be repaired, inherently un-repairable or misrepaired. In short, there is an inherent failure rate in the repair system. For the essential stochastic end points of radiation damage (cancer induction and mutation) the idea of a safe threshold dose and of a safe dose range must be rejected. According to the present scientific knowledge from the various proposed dose-effect relationships only the linear, or the supra-linear is consistent with scientific evidence on human data.
The supporters of threshold doses and even hormetic effects will certainly argue that there are many studies where there was no radiation effect found by the authors. However these studies are unsuited to deciding whether there is a threshold dose or not. This has also been admitted by the authors. The finding of "no effect" can never be an argument for or against a safe dose. Very often the follow up periods were too short, the size of the cohorts too small and the confounding factors were not taken properly into account.
It is, therefore, unsurprising that a large number of epidemiological mortality studies show no significant correlation between cancer induction and low dose radiation exposure.
Nevertheless, arguing from scientific facts and independent epidemiological studies clearly show that the repair systems of the mammalian cell is never 100% exact and that there is no harmless dose threshold. That this has still not been accepted by most national and international commissions suggests that official estimates are no longer a scientific process but rather a political one.

Mortality and occupational exposure to radiation: first analysis of the National Registry for Radiation Workers. BMJ 1992 Jan 25;304(6821):220-5
OBJECTIVE:To study cause specific mortality of radiation workers with particular reference to associations between fatal neoplasms and level of exposure to radiation.
SUBJECTS:95,217 radiation workers at major sites of the nuclear industry.
RESULTS: Most standardised mortality ratios were below 100: 83 unlagged, 85 with a 10 year lag for all causes; 84 unlagged, 86 lagged for all cancers; and 80 for all known other causes, indicating a "healthy worker effect." The deficit of lung cancer (75 unlagged, 76 lagged) was significant at the 0.1% level. Standardised mortality ratios were significantly raised (214 unlagged, 303 lagged) for thyroid cancer, but there was no evidence for any trend with external recorded radiation dose. Dose of external radiation and mortality from all cancers were weakly correlated (p = 0.10), and multiple myeloma was more strongly correlated (p = 0.06); for leukaemia, excluding chronic lymphatic, the trend was significant (p = 0.03; all tests one tailed). The central estimates of lifetime risk derived from these data were 10.0% per Sv (90% confidence interval less than 0 to 24%) for all cancers and 0.76% per Sv (0.07 to 2.4%) for leukaemia (excluding chronic lymphatic leukaemia). These are, respectively, 2.5 times and 1.9 times the risk estimates recommended by the International Commission on Radiological Protection, but 90% confidence intervals are large and the commission's risk factors fall well within the range. The positive trend with dose for all cancers, from which the risk estimate was derived, was not significant. The positive association between leukaemia (except chronic lymphatic leukaemia) was significant and robust in subsidiary analyses. This study showed no association between radiation exposure and prostatic cancer.
CONCLUSION: There is evidence for an association between radiation exposure and mortality from cancer, in particular leukaemia (excluding chronic lymphatic leukaemia) and multiple myeloma, although mortality from these diseases in the study population overall was below that in the general population. The central estimates of risk from this study lie above the most recent estimates of the International Commission on Radiological Protection for leukaemia (excluding chronic lymphatic leukaemia) and for all malignancies. However, the commission's risk estimates are well within the 90% confidence intervals from this study. Analysis of combined cohorts of radiation workers in the United States indicated lower risk estimates than the commission recommends, and when the American data are combined with our analysis the overall risks are close to those estimated by the commission. This first analysis of the National Registry for Radiation Workers does not provide sufficient evidence to justify a revision in risk estimates for radiological protection purposes.

Effects of Low Level Radiation on Hanford Workers
Workers employed at Hanford have been followed since the facility opened in 1944; this is among the longest histories of mortality follow-up of any cohort associated with the Department of Energy among one of the largest groups of workers in the nuclear industry. Furthermore, this cohort of workers has some of the most complete and detailed data on external radiation exposure in the industry. Consequently, this cohort provides some of the best data available with which to assess the relationship between occupational radiation exposure and mortality due to both cancer and non-cancer causes.

Epidemiology of Multiple Myeloma at Four DOE Sites by Dept of Epidemiology, UNC Chapel Hill
We identified 98 multiple myeloma deaths and 391 age-matched controls from a combined roster of 115,143 workers hired before 1979 at Hanford, Los Alamos National Laboratory, Oak Ridge National Laboratory, and the Savannah River site, and followed for vital status through 1990 (1986 for Hanford). Information on prior work history, smoking, medical x-rays, and exposure to physical and chemical agents was derived from personnel, medical, industrial hygiene and health physics records.
Total cumulative radiation doses were similar between cases and controls. However, doses received at ages 45 and above were associated with an average 7% per 10 mSv (one rem) increased risk of multiple myeloma, adjusted for age, race, sex, facility, period of hire, birth cohort, monitoring for internal radionuclide contamination, and external radiation received prior to age 45. The 95% confidence limit for this estimate was 1-13%. For exposure at ages 45 and above, the odds ratio for workers with cumulative doses of 50 mSv (5 rem) or greater compared to workers with cumulative doses of less than 10 mSv was 4.34 (95% CI 1.46-12.90).
The association of multiple myeloma with radiation doses at older ages is consistent with findings from some epidemiological studies of cancer among workers and theoretical expectations that older people are more sensitive to a variety of carcinogens. These findings and other studies of nuclear workers have implications for radiation protection standards for workers and the general public.

STAR FOUNDATION'S MEDICAL STUDIES OF RADIATION-INDUCED CANCER
The formation of STAR (Standing for the Truth About Radiation) arose out of findings from the files of the National Cancer Institute that Suffolk County, in which the Brookhaven National Lab reactors had been operating since 1950, has since registered a 40 percent increase in its age-adjusted breast cancer mortality rate as against a comparable one percent increase for the nation as a whole. Brookhaven asserts that its releases of radioactive strontium, known to affect the immune response, have been too small to be responsible, but this assertion can be tested by a study of strontium-90 levels in baby teeth of children living near the Brookhaven reactors and elsewhere.

International Conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control Seville, Spain, 17--21 Nov 1997
Both the UNSCEAR and the ICRP have considered that, in addition to the individual clinical effects from exposure to high doses of ionizing radiation, there is a probability of induction of detrimental health effects at low doses, and that an increment in probability of harm corresponds to any increment in dose without any dose threshold. This consideration is reflected in the international safety standards.
The biological estimates of health effects of low doses of ionizing radiation and the regulatory approach to the control of low level radiation exposure have both been much debated during recent times. Fundamental research in molecular genetics and cellular biology has progressed significantly over the past few years, increasing our knowledge of the basic mechanisms of those effects. New epidemiological evidence related to human populations and other species has yielded better understanding of the health risks involved, and molecular epidemiology is opening doors for further improvement in our understanding. The results of all these areas of research may have an important effect on the evolution of radiation protection standards. The time therefore seems appropriate to take stock of these new advances and to identify areas toward which new or greater research and development effort might best be directed.

DANGERS OF LOW-LEVEL RADIATION
A study published earlier this year [1991] in the JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION reveals that the occurrence of leukemia (cancer of the blood-forming cells) is 63% higher among white male atomic workers at the Oak Ridge National Laboratory (ORNL) than among all U.S. white males.[1] ORNL, in Oak Ridge, Tennessee, has been a federal research and development laboratory for U.S. nuclear weapons development since 1943.
William R. Hendee, "There's No Free Lunch; The Benefits and Risks of Technologies." JAMA Vol. 265, No. 11 (March 20, 1991), pgs. 1437-1438.
From the Environmental Research Foundation, MD].

LOW LEVEL RADIATION
On the correlation between low dose radiation and weakened immunity, radiation physicist, Dr. Ernest Sternglass, states in a 1986 article: "It appears that perhaps the most serious unanticipated effects of fallout is long-term, persistent immune deficiency." And he clarifies, "It can weaken the immune defenses of the body at very low total doses leading to unexpectedly large increases in infectious diseases and cancers." (Int. J. Biosocial Res., July 1986, p. 18) Initially zealous misrepresentation of the facts led the public to understand that small amounts of radiation were of no special concern. Yet these low levels are exactly the cause of weak immunity and resulting diseases.
Authorities couldn't ignore emerging data and in December 1989, the government sponsored National Academy of Sciences stated in a report titled Biological Effects of Radiation that there was no safe level of radiation.
Low protracted doses of radiation cause physiological damage through the formation of free radicals. A free radical is a molecule with an imbalance in electrons which can destabilize other molecules resulting in cellular damage and disease.
In high, short doses like the Hiroshima bomb blast, radiation primarily causes direct damage to the nucleus of cells where the genes are located that control the functioning of the cell. In contrast, low doses acting continuously over time produce their damage indirectly through the generation of free radicals that destroy cell-membranes, hundreds to thousands of times more efficiently than might be expected in calculations related to high-dose damage. So the everyday amount of radiation that is released as part of the normal operation of the world's 400 nuclear power plants is a very grave concern. Nuclear power plants must have releases in order to function, and these releases, even though they may be partially filtered, allow radiation to go into our air and drinking water, and onto farmland and into our food.
The everyday releases of low-level radioactivity by nuclear power plants has been found to cause several kinds of health damage including premature births, congenital defects, infant mortality, mental retardation, heart ailments, arthritis, diabetes, allergies, asthma, cancer, genetic damage and chronic fatigue syndrome. It has been linked to previously unknown infectious diseases, and the resurgence of old ones by damaging the developing white blood cells originating in the bone marrow and thus weakening the immune system. Dr. Sternglass conjectures what could happen: "With countless thousands of persons having a weaker and weaker immune system as the result of increasing radioactive contamination of the air and food chain, an AIDS mutation-like disease could become a new Black Plague. It's not conceivable that entire nations could be decimated." (Interview in National Catholic Reporter, October 16, 1997).

Extract from NEA W/S, 1993

IARC PR Release, 1994
(from http://www.iarc.fr/preleases/107e.htm)

How much is too much?
There is no question that sufficiently large dosages of radiation can be deadly-- some people at Hiroshima, for example, who survived the blast and fires died of acute radiation sickness (defined). And there's no doubt that somewhat lower doses can damage dividing cells and cause cancer (though it can also kill cancer, too, which explains the popularity of radiotherapy). But what are the effects of even lower exposures, say a few additional chest X-rays, or a basement with some radon (defined) gas in it? Before you tell me it's going to kill you, remember that just because something is dangerous in large doses, doesn't prove that a lower level isn't innocuous or even helpful (think oxygen, vitamin A or television).
[From the Why Files at Wisc.EDU]

1990 BEIR Report substantiates findings of Deadly Deceit's authors
This review of the National Academy of Science's Committee on the Biological Effects of Ionizing Radiation, BEIR V report, issued in 1990, inside of the Appendixes of Deadly Deceit, indicates there may actually be some movement inside the BEIR Committees towards an acknowledgement of the true costs of almost fifty years of the continued development of nuclear technology.
[From Dave "Who can do? Ratmandu!" Ratcliffe dave@sgi.com].

The Health Costs of Low-Level Ionizing Radiation
This site is dedicated to providing information about the health costs of man-made low-level ionizing radiation. Includes Poison Fire, Sacred Earth Testimonies, Lectures, Conclusions from the World Uranium Hearing, Salzburg, 1992 and The Committee For Nuclear Responsibility, Inc .

Radiation-Induced Cancer from Low-Dose Exposure: an Independent Analysis, 1990.
In this book, an expert [John W. Gofman, MD, PhD] who is independent of the radiation community provides the human and physical evidence proving that carcinogenesis from ionizing radiation does occur at the lowest conceivable doses and dose-rates. This finding refutes current claims by parts of the radiation community that very low doses or dose-rates may be safe.
Key findings of the book.
[Copyright The Committee for Nuclear Responsibility, Inc. "a non-profit educational group organized in 1971 to provide independent views about the health effects and sources of ionizing radiation. Authors of CNR publications speak for themselves alone and not for CNR's entire Board, whose members are known for their own independent thinking."]

Dose/response can run backwards?
Some early researched indicated that instead of a protracted or more gentle exposure being less harmful than a short flash, there were some conditions under which it could be the other way around. This passage describes the monumental finding in 1972 by Dr. Abram Petkau, a scientist working for the Canadian Atomic Energy Laboratories in Pinawa, Manitoba, that called into question the underlying foundation of cell damage from exposure to low-level ionizing (penetrating) radiation like that generated from nuclear bomb explosions and in the chain-reactions of nuclear reactors.

Radiation track theory
Summary and references to a survey of "track theory", that argues for an experimental and theoretical inverse dose/effect relationship for some forms of radiation at low doses.

National Cancer Institute Fact Sheet (Radon and Lung Cancer)
Cigarette smoking, the major cause of lung cancer, is responsible for 85 percent of the 170,000 cases diagnosed each year [in the USA]. Radon represents a far smaller risk for lung cancer and is estimated to be responsible for roughly 10 percent, or 17,000 cases per year. This estimate may be as low as 6,000 to as many as 36,000 radon-associated lung cancers per year. Although the association between radon exposure and smoking is not well understood, exposure to the combination of radon gas and cigarette smoke creates a greater risk for lung cancer than either alone. The majority of radon-related cancer deaths occur among smokers.
NCI scientists estimate that the risk of developing lung cancer increased 14 percent for a person living 30 years in a house with a radon level of 150 Becquerels per cubic meter (Bq/m3), which is approximately equal to 4 picocuries per liter, the level at which the U.S. Environmental Protection Agency (EPA) recommends taking action to reduce radon in a house. About 6 percent of U. S. homes have radon levels at or above 150Bq/m3.

Depleted uranium: sources, exposure and health effects (WHO, 1999)
Potentially depleted uranium has both chemical and radiological toxicity with the two important target organs being the kidneys and the lungs. Health consequences are determined by the physical and chemical nature of the depleted uranium to which an individual is exposed, and to the level and duration of exposure.
Long-term studies of workers exposed to uranium have reported some impairment of kidney function depending on the level of exposure. However, there is also some evidence that this impairment may be transient and that kidney function returns to normal once the source of excessive uranium exposure has been removed.
Insoluble inhaled uranium particles, 1-10 [micrometer] in size, tend to be retained in the lung and may lead to irradiation damage of the lung and even lung cancer if a high enough radiation dose results over a prolonged period.
[...]
Limitation on human intake of soluble depleted uranium compounds should be based on a tolerable intake value of 0.5 [microgram] per kg of body weight per day, and that the intake of insoluble depleted uranium compounds should be based on both chemical effects and the radiation dose limits prescribed in the International Basic Safety Standards (BSS) on radiation protection. Exposure to depleted uranium should be controlled to the levels recommended for protection against radiological and chemical toxicity outlined in the monograph for both soluble and insoluble depleted uranium compounds.

Validity of the Linear No-Threshold Theory of Radiation Carcinogenesis at Low Doses by Bernard L. Cohen
In recent years, the former risk estimates have often been reduced by a "dose and dose rate reduction factor", which is taken to be a factor of two. But otherwise, the LNT is frequently used for doses as low as one hundred-thousandth of those for which there is direct evidence of cancer induction by radiation. It is the origin of the commonly used expression "no level of radiation is safe" and the consequent public fear of LLR.
The importance of this use of the LNT is difficult to exaggerate. It is estimated that in the USA, US$85 billion will be spent in cleaning up the Hanford site to avoid LLR, and comparable sums will be spent on government operating sites at Savannah River, Rocky Flats, Fernald and several others. If the LNT is wrong and LLR is harmless, all of this money will be wasted.
[Dr Cohen comments on his own group's study at the U Pitt that finds no significant relationship between theoretical models of radon exposure and mortality data they claim covers 90% of US households. He carefully explains the problems of all such studies -- their likelihood in finding "no result" -- but this may be exacerbated in this case by the "averaging" of data that takes place before analysis. Such techniques are useful in "eliminating noise", but can also be known to "lose information", especially important if an effect is a priori believed to be small].

Dose Calculations by J. K. Soldat
The radiation dose that the public could have potentially received in 1994 from Hanford operations was calculated in terms of the "effective dose equivalent." These dose quantities are given in units of millirem (mrem) (millisievert [mSv])(a) for individuals and in units of person-rem (person-Sv) for the collective dose received by the total population within an 80-km (50 mi) radius of the Site. These quantities provide a way to uniformly express the radiation dose, regardless of the type or source of radiation or the means by which it is delivered. The values given in this report may be compared to standards for radiation protection (Table C.5, Appendix C). This appendix describes how the doses in this report were calculated.

Radon and Cancers Other Than Lung Cancer in Underground Miners: a Collaborative Analysis of 11 Studies
Mortality from non- lung cancer was examined in a collaborative analysis of data from 11 cohorts of underground miners in which radon-related excesses of lung cancer had been established. The study included 64,209 men who were employed in the mines for 6.4 years on average, received average cumulative exposures of 155 working-level months (WLM), and were followed for 16.9 years on average.
For all non-lung cancers combined, mortality was close to that expected from mortality rates in the areas surrounding the mines (ratio of observed to expected deaths [O/E] = 1.01; 95% confidence interval [CI] = 0.95-1.07, based on 1179 deaths), and mortality did not increase with increasing cumulative exposure. Among 28 individual cancer categories, statistically significant increases in mortality for cancers of the stomach (O/E = 1.33; 95% CI = 1.16-1.52) and liver (O/E = 1.73; 95% CI = 1.29-2.28) and statistically significant decreases for cancers of the tongue and mouth (O/E = 0.52; 95% CI = 0.26-0.93), pharynx (O/E = 0.35; 95% CI = 0.16-0.66), and colon (O/E = 0.77; 95% CI = 0.63-0.95) were observed. For leukemia, mortality was increased in the period less than 10 years since starting work (O/E = 1.93; 95% CI = 1.19-2.95) but not subsequently. For none of these diseases was mortality significantly related to cumulative exposure. Among the remaining individual categories of non-lung cancer, mortality was related to cumulative exposure only for cancer of the pancreas (excess relative risk per WLM = 0.07%; 95% CI = 0.01-0.12) and, in the period less than 10 years since the start of employment, for other and unspecified cancers (excess relative risk per WLM = 0.22%; 95% CI = 0.08-0.37).
The increases in mortality from stomach and liver cancers and leukemia are unlikely to have been caused by radon, since they are unrelated to cumulative exposure. The association between cumulative exposure and pancreatic cancer seems likely to be a chance finding, while the association between cumulative exposure and other and unspecified cancers was caused by deaths certified as due to carcinomatosis (widespread disseminated cancer throughout the body) that were likely to have been due to lung cancers. This study, therefore, provides considerable evidence that high concentrations of radon in air do not cause a material risk of mortality from cancers other than lung cancer.

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