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World Health Organization: Prolonged Exposure to Even LOW Le
Mon Nov 2, 2015 04:52
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World Health Organization: Prolonged Exposure to Even LOW Level Radiation Increases the Risk of Cancer
Posted on October 28, 2015 by WashingtonsBlog
Over 300,000 Nuclear Workers from France, the UK and US Studied for Radiation-Cancer Link

A major new study coordinated by World Health Organization’s cancer division – the International Agency for Research on Cancer (IARC) – finds that even low-level radiation increases the risk of cancer, if exposure occurs over time.

The IARC announced last week:

New results from a study coordinated by the International Agency for Research on Cancer (IARC), the cancer agency of the World Health Organization, show that protracted exposure to low doses of ionizing radiation increases the risk of death from solid cancers. The results, published today in The BMJ [the prestigious British Medical Journal], are based on the most powerful study to date and provide direct evidence about cancer risks after protracted exposures to low-dose ionizing radiation.

“The present study demonstrates a significant association between increasing radiation dose and risk of all solid cancers,” says IARC researcher Dr Ausrele Kesminiene, a study co-author. “No matter whether people are exposed to protracted low doses or to high and acute doses, the observed association between dose and solid cancer risk is similar per unit of radiation dose.”

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A collaboration among international partners, evaluated the exposures of more than 300 000 nuclear workers in France, the United Kingdom, and the USA over a period of time between 1943 and 2005.

The scientists involved in the study come from government agencies such as the U.S. National Institute for Occupational Safety and Health, Public Health England Centre for Radiation, Chemical and Environmental Hazards and the International Agency for Research on Cancer, as well as universities including the University of North Carolina, Chapel Hill and Drexel University.

The study confirms – once again – what we’ve been saying for years.

For example, a major 2012 scientific study proves that low-level radiation can cause huge health problems. Science Daily reports:

Even the very lowest levels of radiation are harmful to life, scientists have concluded in the Cambridge Philosophical Society’s journal Biological Reviews. Reporting the results of a wide-ranging analysis of 46 peer-reviewed studies published over the past 40 years, researchers from the University of South Carolina and the University of Paris-Sud found that variation in low-level, natural background radiation was found to have small, but highly statistically significant, negative effects on DNA as well as several measures of health.

The review is a meta-analysis of studies of locations around the globe …. “Pooling across multiple studies, in multiple areas, and in a rigorous statistical manner provides a tool to really get at these questions about low-level radiation.”

Mousseau and co-author Anders Mřller of the University of Paris-Sud combed the scientific literature, examining more than 5,000 papers involving natural background radiation that were narrowed to 46 for quantitative comparison. The selected studies all examined both a control group and a more highly irradiated population and quantified the size of the radiation levels for each. Each paper also reported test statistics that allowed direct comparison between the studies.

The organisms studied included plants and animals, but had a large preponderance of human subjects. Each study examined one or more possible effects of radiation, such as DNA damage measured in the lab, prevalence of a disease such as Down’s Syndrome, or the sex ratio produced in offspring. For each effect, a statistical algorithm was used to generate a single value, the effect size, which could be compared across all the studies.

The scientists reported significant negative effects in a range of categories, including immunology, physiology, mutation and disease occurrence. The frequency of negative effects was beyond that of random chance.

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“When you do the meta-analysis, you do see significant negative effects.”

“It also provides evidence that there is no threshold below which there are no effects of radiation,” he added. “A theory that has been batted around a lot over the last couple of decades is the idea that is there a threshold of exposure below which there are no negative consequences. These data provide fairly strong evidence that there is no threshold — radiation effects are measurable as far down as you can go, given the statistical power you have at hand.”

Mousseau hopes their results, which are consistent with the “linear-no-threshold” model for radiation effects, will better inform the debate about exposure risks. “With the levels of contamination that we have seen as a result of nuclear power plants, especially in the past, and even as a result of Chernobyl and Fukushima and related accidents, there’s an attempt in the industry to downplay the doses that the populations are getting, because maybe it’s only one or two times beyond what is thought to be the natural background level,” he said. “But they’re assuming the natural background levels are fine.”

“And the truth is, if we see effects at these low levels, then we have to be thinking differently about how we develop regulations for exposures, and especially intentional exposures to populations, like the emissions from nuclear power plants, medical procedures, and even some x-ray machines at airports.”

And see this.

Physicians for Social Responsibility notes:

According to the National Academy of Sciences, there are no safe doses of radiation. Decades of research show clearly that any dose of radiation increases an individual’s risk for the development of cancer.

“There is no safe level of radionuclide exposure, whether from food, water or other sources. Period,” said Jeff Patterson, DO, immediate past president of Physicians for Social Responsibility. “Exposure to radionuclides, such as iodine-131 and cesium-137, increases the incidence of cancer. For this reason, every effort must be taken to minimize the radionuclide content in food and water.”

“Consuming food containing radionuclides is particularly dangerous. If an individual ingests or inhales a radioactive particle, it continues to irradiate the body as long as it remains radioactive and stays in the body,”said Alan H. Lockwood, MD, a member of the Board of Physicians for Social Responsibility.

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Radiation can be concentrated many times in the food chain and any consumption adds to the cumulative risk of cancer and other diseases.

John LaForge writes:

The National Council on Radiation Protection says, “… every increment of radiation exposure produces an incremen­tal increase in the risk of cancer.” The Environmental Protection Agency says, “… any exposure to radiation poses some risk, i.e. there is no level below which we can say an exposure poses no risk.” The Department of Energy says about “low levels of radiation” that “… the major effect is a very slight increase in cancer risk.” The Nuclear Regulatory Commission says, “any amount of radiation may pose some risk for causing cancer … any increase in dose, no matter how small, results in an incremental increase in risk.” The National Academy of Sciences, in its “Biological Effects of Ionizing Radiation VII,” says, “… it is unlikely that a threshold exists for the induction of cancers ….”

Japan Times reports:

Protracted exposure to low-level radiation is associated with a significant increase in the risk of leukemia, according to a long-term study published Thursday in a U.S. research journal.

The study released in the monthly Environmental Health Perspectives was based on a 20-year survey of around 110,000 workers who engaged in cleanup work related to the Chernobyl nuclear plant disaster in 1986.

Scientists from the University of California, San Francisco, the U.S. National Cancer Institute and the National Research Center for Radiation Medicine in Ukraine were among those who participated in the research.

Indeed, the overwhelming consensus among radiation experts is that repeated exposure to low doses of radiation can cause cancer, genetic mutations, heart disease, stroke and other serious illness (and see this.) If a government agency says anything else, it’s likely for political reasons.

The top U.S. government radiation experts – like Karl Morgan, John Goffman and Arthur Tamplin – and scientific luminaries such as Ernest Sternglass and Alice Stewart, concluded that low level radiation can cause serious health effects.

A military briefing written by the U.S. Army for commanders in Iraq states:

Hazards from low level radiation are long-term, not acute effects… Every exposure increases risk of cancer.

(Military briefings for commanders often contain less propaganda than literature aimed at civilians, as the commanders have to know the basic facts to be able to assess risk to their soldiers.)

The briefing states that doses are cumulative, citing the following military studies and reports:

ACE Directive 80-63, ACE Policy for Defensive Measures against Low Level Radiological Hazards during Military Operations, 2 AUG 96

AR 11-9, The Army Radiation Program, 28 MAY 99

FM 4-02.283, Treatment of Nuclear and Radiological Casualties, 20 DEC 01

JP 3-11, Joint Doctrine for Operations in NBC Environments, 11 JUL 00

NATO STANAG 2473, Command Guidance on Low Level Radiation Exposure in Military Operations, 3 MAY 00

USACHPPM TG 244, The NBC Battle Book, AUG 02

Many studies have shown that repeated exposures to low levels of ionizing radiation from CT scans and x-rays can cause cancer. See this, this, this. this, this, this, this, this, this and this.

Research from the University of Iowa concluded:

Cumulative radon exposure is a significant risk factor for lung cancer in women.

And see these studies on the health effects cumulative doses of radioactive cesium.

The European Committee on Radiation Risk notes:

Cumulative impacts of chronic irradiation in low doses are … important for the comprehension, assessment and prognosis of the late effects of irradiation on human beings ….

And see this.

The New York Times’ Matthew Wald reported in 2012:

The Bulletin of the Atomic Scientists[’] May-June issue carries seven articles and an editorial on the subject of low-dose radiation, a problem that has thus far defied scientific consensus but has assumed renewed importance since the meltdown of the Fukushima Daiichi reactors in Japan in March 2011.

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This month a guest editor, Jan Beyea [who received a PhD in nuclear physics from Columbia and has served on a number of committees at the National Research Council of the National Academies of Science] and worked on epidemiological studies at Three Mile Island, takes a hard look at the power industry.

The bulletin’s Web site is generally subscription-only, but this issue can be read at no charge.

Dr. Beyea challenges a concept adopted by American safety regulators about small doses of radiation. The prevailing theory is that the relationship between dose and effect is linear – that is, that if a big dose is bad for you, half that dose is half that bad, and a quarter of that dose is one-quarter as bad, and a millionth of that dose is one-millionth as bad, with no level being harmless.

The idea is known as the “linear no-threshold hypothesis,’’ and while most scientists say there is no way to measure its validity at the lower end, applying it constitutes a conservative approach to public safety.

Some radiation professionals disagree, arguing that there is no reason to protect against supposed effects that cannot be measured. But Dr. Beyea contends that small doses could actually be disproportionately worse.

Radiation experts have formed a consensus that if a given dose of radiation delivered over a short period poses a given hazard, that hazard will be smaller if the dose is spread out. To use an imprecise analogy, if swallowing an entire bottle of aspirin at one sitting could kill you, consuming it over a few days might merely make you sick.

In radiation studies, this is called a dose rate effectiveness factor. Generally, a spread-out dose is judged to be half as harmful as a dose given all at once.

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Dr. Beyea, however, proposes that doses spread out over time might be more dangerous than doses given all at once. [Background] He suggests two reasons: first, some effects may result from genetic damage that manifests itself only after several generations of cells have been exposed, and, second, a “bystander effect,” in which a cell absorbs radiation and seems unhurt but communicates damage to a neighboring cell, which can lead to cancer.

One problem in the radiation field is that little of the data on hand addresses the problem of protracted exposure. Most of the health data used to estimate the health effects of radiation exposure comes from survivors of the Hiroshima and Nagasaki bombings of 1945. That was mostly a one-time exposure.

Scientists who say that this data leads to the underestimation of radiation risks cite another problem: it does not include some people who died from radiation exposure immediately after the bombings. The notion here is that the people studied in ensuing decades to learn about the dose effect may have been stronger and healthier, which could have played a role in their survival.

Still, the idea that the bomb survivor data is biased, or that stretched-out doses are more dangerous than instant ones, is a minority position among radiation scientists.

Dr. Beyea writes:

Three recent epidemiologic studies suggest that the risk from protracted exposure is no lower, and in fact may be higher, than from single exposures.

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Conventional wisdom was upset in 2005, when an international study, which focused on a large population of exposed nuclear workers, presented results that shocked the radiation protection community—and foreshadowed a sequence of research results over the following years.

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It all started when epidemiologist Elaine Cardis and 46 colleagues surveyed some 400,000 nuclear workers from 15 countries in North America, Europe, and Asia—workers who had experienced chronic exposures, with doses measured on radiation badges (Cardis et al., 2005).

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This study revealed a higher incidence for protracted exposure than found in the atomic-bomb data, representing a dramatic contradiction to expectations based on expert opinion.

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A second major occupational study appeared a few years later, delivering another blow to the theory that protracted doses were not so bad. This 2009 report looked at 175,000 radiation workers in the United Kingdom ….

After the UK update was published, scientists combined results from 12 post-2002 occupational studies, including the two mentioned above, concluding that protracted radiation was 20 percent more effective in increasing cancer rates than acute exposures (Jacob et al., 2009). The study’s authors saw this result as a challenge to the cancer-risk values currently assumed for occupational radiation exposures. Thatnue is, they wrote that the radiation risk values used for workers should be increased over the atomic-bomb-derived values, not lowered by a factor of two or more.

Continues at:
http://www.washingtonsblog.com/2015/10/world-health-organization-prolonged-exposure-to-even-low-level-radiation-increases-the-risk-of-dying-from-cancer.html
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In 2007, one study—the first of its size—looked at low-dose radiation risk in a large, chronically exposed civilian population; among the epidemiological community, this data set is known as the “Techa River cohort.” From 1949 to 1956 in the Soviet Union, while the Mayak weapons complex dumped some 76 million cubic meters of radioactive waste water into the river, approximately

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