100 mSv, 10000 mrem, cancer, cancer risks, excess cancer deaths, excess cancer risks, exposure to ionizing radiation, fatal cancer risks, France, Hormesis, Linear No Threshold Model, LNT, low dose radiation, no safe dose of radiation, Nuclear cleanup, nuclear effluents, nuclear energy, nuclear power, nuclear worker cancer, nuclear worker cohort, nuclear workers, public exposure nuclear effluents, risk, UK, US
Update-clarification of the study below found here: https://miningawareness.wordpress.com/2015/12/19/another-look-at-the-recent-low-dose-radiation-exposure-study-inworks/
Just in time to debunk the US NRC proposal for increasing radiation exposure to the general population from 0.25 mSv (EPA) to 100 mSv: http://www.regulations.gov/#!docketDetail;D=NRC-2015-0057 (Comment Deadline Nov. 19th) is a new study of nuclear workers exposed to cumulative doses with a median average (half-above, half-below) of 4.1 mSv, and an overall arithmetic average (mean) of 20.9 mSv: “Results suggest a linear increase in the rate of cancer with increasing radiation exposure. The average cumulative colon dose estimated among exposed workers was 20.9 mGy (median 4.1 mGy). The estimated rate of mortality from all cancers excluding leukaemia increased with cumulative dose by 48% per Gy (90% confidence interval 20% to 79%), lagged by 10 years“. (See Richardson et. al. below). One Gy is 1000 mSv, in the context of this study, or 10 years worth of the US NRC 100 mSv proposal. This is mortality, that is death. The numbers with cancer will be greater – around double. The current international standard allows 1 mSv per year exposure for the general population (the US EPA still has 0.25 per year), which over the course of a lifetime leads to 80 mSv or more cumulative exposure (ignoring the fact that it accumulates in the environment and body). The current US NRC proposal would lead to a cumulative exposure of 8,000 mSv over an 80 year lifetime. The alert will notice that the 20.9 mGy (mSv in this context) dose is similar to the dose of the Fukushima worker who was just given workers comp because he developed leukemia.
The new 3 country study, which seems to represent a re-evaluation of a 15 country study, minus 12 countries, still supports the Linear No Threshold Model (LNT) – increased exposure to radiation is increased risk. There is no threshold. The funding for the new study comes from pro-nuclear governments (UK, US, Japan, France) and pro-nuclear entities within governments (USDOE, French ISRN), and even the French state owned nuclear industry (Areva, EDF). Thus, it appears safe to assume that the risks may be higher than the new study shows, but certainly not lower.
The earlier 15 country study (Cardis et. al, 2005), whose funding appears slightly less tainted, and certainly more diverse, concluded: “Our estimates suggest that a cumulative exposure of 100 mSv would lead to a 9.7% (1.4 to 19.7%) increased mortality from all cancers excluding leukaemia and a 5.9% ( − 2.9 to 17.0%) increased mortality from all cancers excluding leukaemia, lung, and pleura compared with background rates. The corresponding figure is 19% ( < 0 to 84.7%) for mortality from leukaemia excluding chronic lymphocytic leukaemia. Less than 5% of workers in this study received cumulative doses of the order of 100 mSv over their entire career,…”
Cohorts of workers in the nuclear industry in 15 countries.
Participants 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years.
Main outcome measurements
Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities.
The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv ( < 0 to 8.47)
European Union (contracts F13P-CT930066, F14P-CT96-0062, FIGH-CT1999-20001); US Centers for Disease Control (Co-operative agreement U50/CCU011778); Canadian Nuclear Safety Commission; Japanese Institute for Radiation Epidemiology, Australian Nuclear Science and Technology Organisation; Nuclear Research Center (SCKCEN), Belgium; Health Canada and Statistics Canada; La Ligue Nationale contre le Cancer, France; La Compagnie Générale des Matière Nucléaire, France; Electricité de France; Ministry of Education, Culture, Sports, Science and Technology in Japan; Ministry of Science and Technology (MOST) in Korea; Spanish Nuclear Safety Council; US Department of Energy. These sponsors had no role in study design, data collection, analysis, or interpretation. IT -C received funding from the Association pour la Recherche contre le Cancer (ARC, France); MSP and DBR were the recipients, respectively, of an IARC postdoctoral fellowship and of an ORAU fellowship during their stay at IARC.” “Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries“; E Cardis, et. al. BMJ. 2005 Jul 9; 331(7508): 77. http://www.ncbi.nlm.nih.gov/pubmed/15987704 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC558612/
(The above study seems more clearly written than the new one.) The Canadian data showed greater risk than the others. Thus, Canada was not included in the new evaluation. But, they excluded a total of 12 countries in the new evaluation. Either way the studies show that there is no safe dose of radiation!
Bravo to the authors, and British Medical Journal, for their timing of Oct. 20th, exactly 30 days before the US NRC Linear No Threshold vs. “Hormesis” deadline! Bravo that they made it available Creative Commons, Non-commercial (though as a government funded document, it should be copyright free or OGL).
See original PDF here: http://www.bmj.com/content/bmj/351/bmj.h5359.full.pdf