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The Low Level Radiation Campaign
The Low Level Radiation Campaign is primarily focused on advancing the theory that there is a relationship between Low Levels of radiation and negative health effects. Although the primary focus is on ionising radiation, there have recently been studies on the possible negative health effects of non-ionising radiation. An idea central to the claims made by the LLRC, is that the negative health effects of radiation have been considerably underestimated by official agencies. While LLRC maintains that the risks of external radiation dose are reasonably well described by the International Commission on Radiological Protection, the LLRC also maintains that the risk due to radioactive material uptake is underestimated. The LLRC theorizes that, in many circumstances, internal radiation is far more dangerous than predicted by the ICRP's models. Studies endorsed by the LLRC relate to cancer induction on the cellular level caused by radioactive isotopes released by industries which use the radioactive material. The LLRC web site [8] contains a variety of articles on the subject. The LLRC was started in 1993 under the aegis of the Green Party but in 1996 it became independent due to a grant from the Goldsmith Foundation. In 1999 it was registered by Companies House as a Company Limited by Guarantee. Additional recommended knowledge
Central thesis of the LLRCLLRC contends that radiation protection standards are fundamentally flawed based on two basic grounds. First is the idea that radiation dose is an average energy transfer into large volumes of undifferentiated body tissue separate from internal radiation sources and from the radioactive decay of unstable elements within the body. LLRC cites a number of authorities who have criticised this on conceptual grounds (see [9]). Second, is the idea that estimates of health hazards are based primarily on the Life-Span Studies (LSS) of the health of people who survived exposure to acute external irradiation from the Atomic Bombs detonated on the Japanese cities of Hiroshima and Nagasaki during World War II. LLRC points out that the LSS suffers from a series of methodological flaws which include
The official French radiation risk agency IRSN (Institut de Radioprotection et de Sûreté Nucléaire) and the [10] European Committee on Radiation Risk (ECRR) have given support to the point of view of the LLRC. The IRSN have reported (see [11], and English edition) that it is reasonable for the ECRR to have reservations about ICRP's recommendations on radiation risk, since ICRP bases its advice on the health effects of external radiation from atomic bombs. However, IRSN have stated that arguments of the ECRR are not convincing" and that the ECRR "are not using a strict and constant scientific approach. The main conclusion of the IRSN is that further research is required on a series of topics before a final conclusion can be made. The LLRC's response, as stated in a number of public meetings including a mass lobby of the House of Commons, London in February 2007, is that the European Committee accepts that its approach is an approximation but that there is a pressing and present need for further and more strict regulation of radioactive releases. They argue that waiting for the results of research (which may take many years to perform) is not a reasonable option. The ECRR propose new weighting factors for immediate, interim use to compensate for the shortcomings of the ICRP approach. Below is shown a table in which the ICRP and ECRR risk factors are compared.
The hot coal analogyLLRC holds that on biological and radiological grounds internal contamination of body tissue by some types of radioactivity is inherently more dangerous than predicted on the basis of the Hiroshima and Nagasaki studies. According to the LLRC the reason for the discrepancy is that external irradiation is uniformly distributed on a macroscopic level, with all cells receiving the same amount of ionising energy, while many forms of radioactivity when inside the body deliver their energy exclusively to microscopic volumes of cells; some types of radioactive decay are heterogeneous even on the far smaller molecular level. LLRC's favourite analogy for this heterogeneity of energy distribution is that external irradiation is like a person sitting by a fire and warming himself. If the person were to reach into the fire to take a burning coal and eat it the local tissue effects would probably be fatal, even if a similar or smaller amount of energy had thereby been absorbed by the person's body. Is radiation dose meaningless?On such logic as the hot coal analogy LLRC holds that radiation dose is virtually meaningless in some circumstances. In support of this they cite [2] Chapter 2.1 paragraph 11 of the CERRIE Majority Report:
LLRC also cite IRSN
LLRC also cites section 3.2. Summary of health effects caused by ionising radiation of the 2004 draft of the ICRP's latest Recommendations [4] and the 2003 Recommendations of the ECRR [5] Impact on interpretation of epidemiologyLLRC states that, since official radiation risk agencies universally quantify risk in terms of average dose, there are many types of exposure for which official reassurances are highly questionable and that it is not tenable to assert that disease phenomena like the Seascale cluster of childhood leukaemia could not be caused by radiation on the grounds of low doses. Scale of implied error in risk estimatesChildhood leukaemiaCOMARE (the UK Government's advisory Committee on Medical Aspects of Radiation in the Environment) has reported [6] that, on the basis of data for leukaemia derived from study of the Japanese bomb survivors, doses from Sellafield were between 200 and 300 times too small to cause the number of cases observed in Seascale. LLRC states that this is not evidence that radiation did not cause the Seascale cluster, but evidence that the risk model is in error by a factor of 200 – 300. Infant leukaemia after ChernobylLLRC also points to infant leukaemia after the Chernobyl accident [7] as unequivocal evidence of an error of two orders of magnitude in ICRP risk factors. Cancer in Sweden after ChernobylLLRC states that there is a large amount of evidence of this nature Another study cited by LLRC is the Tondel et al. study of cancer in Sweden after Chernobyl [8]. According to the LLRC's publication Radioactive Times, this demonstrates an error in ICRP of between 125 and 600. LLRC states that the extra cancers which were registered in the 9 post-accident years 1988 to 1996 are at least 125 times the incidence predicted by ICRP on the basis of doses from Caesium in Sweden, which was measured and mapped in detail. This 125-fold figure is based on the assumption that the effect is transient and that there would be no excess after 1996. However, the lifetime follow-up of Hiroshima survivors shows a consistent upward trend and it is likely that the effect seen in Sweden is typical of the distribution of risks throughout life and that cancer incidence will continue to be higher than expected. According to LLRC's calculations this would imply a 600-fold error in ICRP’s modelling. The official Swedish radiation protection institute, SSI, has criticised the Tondel study [12], rejecting any suggestion that it shows a cancer increase caused by or related to the Chernobyl fallout. An internal studyA further example relating specifically to internal radiation is a published study of nuclear industry workers diagnosed with prostate cancer [9]. This shows a statistically significant and substantially increased risk of prostate cancer associated with internal contamination. Responding in the British Medical Journal[10], UKAEA calculated that, if the internal radionuclides were causing the cancer, then internationally accepted risk factors were probably in error by more than 1000-fold. Chernobyl studiesThe LLRC web site has summaries [13] of Russian, Belarusian and Ukrainian studies since the Chernobyl disaster. The Campaign is severely critical of the ICRP for failing to cite or discuss any epidemiological findings from Chernobyl affected territories. They refer to this [14] as systematic theft of the greatest opportunity the human race has ever had to study the health effects of a major reactor accident. LLRC view of "the TORCH report" on ChernobylThe LLRC condemns the TORCH report as a theoretical review of a small part of the evidence accrued in twenty years since the Chernobyl disaster [15]
PersonnelDr. Christopher Busby is the principal scientific adviser to the Low Level Radiation Campaign. Dr. Busby is a Director of research consultancy Green Audit [16], a past member of CERRIE (the UK Government's Committee Examining Radiation Risks of Internal Emitters [17]) and the Ministry of Defence Depleted Uranium Oversight Board ([18]). He is Scientific Secretary of the European Committee on Radiation Risk [19]. His curriculum vitae can be viewed at [20].
Richard Bramhall is a founder member of the Low Level Radiation Campaign and is its Company Secretary. He is a retired professional double bass player, originally trained at the Royal College of Music in London in the 1960s. He worked in many orchestras beginning with the Royal Opera House when he left the RCM in 1969, then the Royal Philharmonic Orchestra, and at various times the English Chamber Orchestra and the London Symphony Orchestra.
Since the Low Level Radiation Campaign is a company under UK law, the identities of the directors are in the public domain and can be seen on the Companies House website. "Non-research" methodsCivil disobedienceChristopher Busby gave an annual South Place Ethical Society lecture in London in 1994 on non-violent direct action. He also argued the Green Party into embracing non-violent direct action in the same year as a legitimate political strategy. He has engaged in civil disobedience, for instance he organized the chain up at Trawsfynydd. This was an event where Chris Busby, together with a number of other protesters, chained himself to the gate to protest against the restart of the power reactors under conditions which Dr Busby and others considered to be unsafe. This chaining by a person of themselves to an object is a method of protest which has been used by suffragettes in the UK and by other groups including Bertrand Russell's Committee of 100. Dr. Busby was a prime mover in setting up a Green Committee of 100 in 1994. The last known action of the Green Committee of 100 was the invasion of the British Nuclear Energy Society's 1997 International Conference on Low Level Radiation and Health in Stratford (England). In this, Richard Bramhall, dressed and made-up as the Grim Reaper, chained himself to the podium while epidemiologist Sir Richard Doll was delivering a keynote address. Other activists distributed copies of Dr. Busby's book Wings of Death to delegates. SatireIn contrast to nuclear / radiological organisations (such as the International Atomic Energy Agency and the ITU) LLRC regards itself as a campaigning organisation and uses modes of communication appropriate to that status. Richard Bramhall has described parts of the LLRC web site as satire. Another Wikipedia editor has identified the following three quotes, taken from the jargon buster of the LLRC [22]. Committee Examining Radiation Risks of Internal Emitters. An oppositional committee set up by the UK Environment Minister in 2001. Notable for caving into legalistic threats from Departmental lawyers right at the end of its two-and-a-half year deliberations.[23] and The LLRC also describes the ICRP as the Incestuous Cabal for Radioactive Pollution and The LLRC comments that the idea of Controllable Dose is "(the) ICRP's idea for allowing the nukes to pollute anybody and everybody with radioactivity up to an arbitrary threshold ". Cartoons and lampoonsOther styles are cartoons, including a Teddy and Dolly series and Roger Radon penned by Chris Busby. A series by Richard Bramhall features a fictional detective called Sergeant Mercer and his sidekick Constable Joskin (see [24]). There are lampoons of poems such as Owen's Strange Meeting and of the Wombles' Song. Good King Roger is a fairy story about ICRP's 1999 proposal to abandon the concept of collective dose. Criticism from other scientistsIn 2002 it was claimed by David Cartwright (a spokesperson for the British Nuclear industry)[25] that Dr Busby runs his own anti-nuclear company and makes a living out of producing these anti-nuclear reports
Disagreement with other greensThe LLRC is in disagreement with a "Greenpeace consultant (named Pete Roche) who is quoted as having stated an important report written by the The Low Level Radiation Campaign was "...was not included [in the CERRIE final report] because it was not factually correct". The LLRC publicly invited Pete Roche to enter into a debate (December 2004), but according to the LLRC to date "Mr. Roche has never responded".[28] Microwaves and mobile phonesIn the past the LLRC has normally avoided the subject of non-ionizing radiations such as microwaves, Ultra-Violet, Infra-red and radio waves as it has considered itself to be an organisation which should deal with ionizing radiations. However in 2007 it has done some work on the subject of a proposed mobile phone transmitter (base station) which was proposed to be sited within a church in Aberystwyth(Wales).[29] This work consisted of an epidemiology study of human health using a health questionnaire, it was planned that a study before the equipment was installed would be followed by a second survey after the equipment had started operations but as the planning application for the equipment to Ceredigion District Council was withdrawn the study was terminated at an early stage. This activity has continued[30] recently in the USA Chris Busby has been involved in a campaign against a phone tower which was to be established in a town. Radioactive marine pollutionThesisOne of the key areas LLRC is concerned with is releases of radioactivity to the world's seas. They claim ([31]) that increased risks of cancer and leukaemia near the Irish Sea are discernible in official statistics and they believe this provides evidence of a large error in conventional radiation risk estimates. Chris Busby, LLRC's main scientific adviser, has published a book on the subject (Wolves of Water, 2006). It was reasoned years ago that if any form of waste was added to the sea that the substance would be diluted to a very low concentration which would not be able to pose a threat to humans (or other organisms).[citation needed] Chris Busby argues that even if waste is added to the sea then it is likely to be reconcentrated by physical and biological processes and then pose a threat to humans and other organisms.[citation needed] This reconcentration thesis is not totally new, other scientists who are unconnected to Busby have found that some radioisotopes can be reconcentrated.[citation needed] Comparison with the findings of other workers (environmental radiochemistry)Natural backgroundAs much of LLRC's work involves a discussion of the levels of radioactivity within the environment it is important to note that that radioactivity is present everywhere (and has been since the formation of the earth). According to the International Atomic Energy Agency, one kilogram of soil typically contains the following amounts of the following four natural radioisotopes 370 Bq 40K (typical range 100-700 Bq), 25 Bq 226Ra (typical range 10-50 Bq), 25 Bq 238U (typical range 10-50 Bq) and 25 Bq 232Th (typical range 7-50 Bq).[16] It is important to note that these values are average values and some soils may vary greatly from these norms. LLRC's view is that comparisons with natural background are largely spurious [32], since nuclear technology has created novel isotopes such as Plutonium and Strontium-90 which have unique characteristics not found in nature. They also state [33] that technologies such as the use of uranium in weapons create relatively insoluble particles smaller than 5 micrometres which are not found in nature. It should be noted that very fine particles of clay minerals (5 to 0.1 µm)[17] are often present in soil and because the Kd (for binding to clay) for many natural radioisotopes is high it is possible that fine particles of clay bearing radioisotopes could be found in soil (Kd values for clay Ra >1000, Th 90-10000, U 2-490000[18]). The behaviour of uranium in soil depends on many factors (such as concentration of humic acids and redox conditions), when the uranium is mobile it is possible that uranium may leach out of soil minerals into the soil water where it will decay thus forming radium and thorium which can bind to the surfaces of soil particles. Sea and river siltIt is well known that some plants are able to absorb and concentrate metals within their tissues (see hyperaccumulators for further detail) and it is known that iodine was first isolated from seaweed in France which suggests that seaweed is an iodine hyperaccumulator. For instance a study on the radioactivity found in oysters found in the Irish Sea, these were found by gamma spectrscopy to contain the fission products 141Ce, 144Ce, 103Ru, 106Ru, 137Cs, 95Zr and 95Nb. In addition a zinc activation product (65Zn) was found, this is thought to be due to the corrosion of magnox fuel cladding in cooling ponds.[19] It is likely that the modern releases of all these isotopes from Windscale is smaller as the waste water is now routed via an ion exchange plant where the many of metal ions are removed from waste water using the Enhanced Actinide Removal Plant (EARP) and with faujasite (Zeolite X) in the Site Ion Exchange Efficient Plant (SIXEO). For instance Busby quotes Garland et al. 1989 who reported the plutonium activity in Welsh inter tidal sediments which suggests that the closer a site is to Sellafield the higher the concentration of plutonium in the silt is. Some relationship cen be seen but the scatter of points is large (R² = 0.3683) if the data is fitted to an exponential line.
Hot particlesBusby in his book (Wolves of Water[34]) has written that hot particles (plutonium) have been found in the Irish Sea and that these particles are migrating onto the land,[22]. It is interesting to note that the International Atomic Energy Agency report on Mururoa states on page 43 (chapter 4) that some particles containing 1 mg (100 kBq) of plutonium are present on the island that was used for French nuclear experiments.[23] On page 220 it indicates that such a particle could deliver a dose of between 1 and 300 Gy per hour to a worm which lives in the silt. From an examination of the book by Busby it is likely that the hot particles which he has reported are smaller than those reported at Mururoa, but Busby suggests that official health statistics show the Irish Sea hot particles are causing effects in human populations along the coast. Americium in smoke detectorsOne article by Rose Tilly, which is reprinted[35] on the site, suggests that the gamma rays from the americium present in smoke detectors is a grave threat to the general public. She claims that a count rate of 500 events per second can be recorded near a smoke detector using a scintillation counter. The LLRC reply that they have repeated her measurements and have been unable to observe such a high radiation level, they have observed a smaller increase of radiation when a smoke detector is placed one inch away from a detector. They suggest that the smoke detectors used by Rose should be subjected to a more detailed radioanylsis to determine if the radioactive sources within them contain some additional radioisotopes. It is interesting to note that the article by Rose has a clear error which suggests other errors might be present in the article, this error is her assertion that americium is a fission product, americium is an activation product of plutonium and hence is very different to the fission products. The Second Event theoryOne of the major ideas presented in the LLRC web site is the hypothesis, first advanced by Chris Busby in his 1995 book Wings of Death [24], that radionuclides which decay sequentially may have an enhanced ability to cause heritable genetic defects. Split dose experimentsIn some 1970s experiments comparing the effects of a single X-ray exposure with two exposures at the same total dose it was observed that the transformation rate was increased by a factor of two when two 250mGy doses were administered (with a 7.5 hour time between the doses) compared with a single dose of 500 mGy.[25][26][27] In Wings of Death Busby claims that these results support his Second Event hypothesis. However no consensus has been reached regarding the question of "does exposure to radiation increase or decrease the radiosensitivity of cells?", it has been shown that for large doses of X-rays fractionation can induce radioresistance in tissue[28], while it has been shown that preexposure to radiation (50 to 100 mGy) results in four hours time in a small reduction of the ability of a 8 Gy dose to damage DNA in intact cells due to a shift in the cell cycle[29] Dose-rate experimentsMainstream science is divided on the question of does division of a radiation dose into smaller doses reduce or increase the likelihood of the induction of cancer. In a recent paper[30] a dose of 1 Gy was delivered to the cells (at constant rate from a radioactive source) over a series of lengths of time. These were between 8.77 and 87.7 hours, the abstract stated for a dose delivered over 35 hours or more (low dose rate) no transformation of the cells occurred. Also for the 1 Gy dose delivered over 8.77 to 18.3 hours that the biological effect (neoplastic transformation) was about 1.5 times smaller than that which that had been observed using a single high dose rate of X-ray photons of similar energy. Likewise it has been reported that [31] that fractionation of gamma irradiation reduces the likelihood of a neoplastic transformation. It is clear that the findings in these two papers do not agree with the hypothesis of the second event theory. But in a further paper[32] it is reported that for both fast neutron and gamma rays from Cs-137 that preexposure can increase the ability of a second dose to induce a neoplastic transformation. Timing as a crucial aspect of the Second Event theoryAs described in the CERRIE Majority Report
This part of the argument is based on experimental results with cell cultures demonstrating the postulated sensitive phase.[33], [34] It should be noted that radiation affects tissue in the form of discrete track of charged particles. As Professor Dudley Goodhead puts it
Also, it is important to be aware that the enhancement referred to in the theory concerns relative probabilities; the probability of two tracks (or events) affecting any target tissue from a sequential emitter, compared with the probability of two tracks from another type of exposure always assuming, for the sake of the comparison, that the dose from the sources is the same. Examples of isotopes which undergo several decays132Sn
The above table illustrates that not all steps in a decay chain are potential second events; here only the decay of Antimony to Tellurium results in a candidate. This is because only the Tellurium has a sufficiently long half-life to have much chance of providing the second decay at the critical point in the cell repair cycle. The others are too short. The above decay chain is only likely to be important for a consideration of nuclear warfare and serious nuclear accidents involving criticality (eg chernobyl) as the half lives of all the isotopes are relatively short (minutes and days). Also normal operating conditions in a power reactor it is likely to be the case that the antimony is unlikely to be released from the uranium dioxide fuel unless the fuel was badly damaged. 90Sr
Note that these fission yields were calculated for 235U assuming thermal neutrons (0.0253 eV) using data from the chart of the nuclides.[36] 222RnIt is noteworthy that in the decay chain of radium-226/radon-222 a large number of shortlived radioisotopes exist which could subject a cell to repeated radioactive events. This is because the daughters of radon often become attached to smoke and dust particles and are then able to lodge in the lungs.[37]
Reactions to the theory by other scientistsAgainstBusby's views are often seen as controversial. The NRPB published a counterblast against the second event theory in which they suggest that it is a theory which is unlikely to be correct.[36] [38]. Busby in an open letter to the editor published a rebutal of this paper which can be read on line.[37], this in turn resulted in the NRPB writing a letter of their own to the journal in which they rebut the rebuttal letter (Again this can be read on line).[38] The Committee Examining Radiation Risk of Internal Emitters (CERRIE) concluded in its Majority Report [39] that the available studies to date offered little or no support to the second event theory […] Instead the evidence substantially contradicted it. The Report found a lack of biological plausibility for the basic preconditions of the SET; a lack of supporting evidence in the proponents’ reviews of the SET; weakness in the few studies cited in support of the SET; and absence of supporting evidence from experimental studies in an independent review of commissioned by the Committee. NeutralSpeaking at a 1996 Symposium in the House of Commons, London, Professor Dudley Goodhead of the Medical Research Council said the theory was nicely specified and open, by its nature, to a variety of experimental tests.[40] He added that he and his colleagues would be happy to discuss ways in which it could be tested. Another issue, he said, was that if the hypothesis were to be valid
However this should not be understood as an endorsement of the theory as it does not comment on the question of is the theory correct or incorrect. It is simple to understand that other theories (if correct) would have far reaching effects upon our understanding and experience of life. ForThe Minority Report [42] answers the CERRIE majority report by arguing that the SET's critics on the Committee, who had conducted a theoretical analysis of the theory (which is not reported in the Majority Report) had misunderstood the significance of the doses needed to move a cell out of quiescence. They further argued that the critics had used wrong data for cell packing and inappropriate dose criteria. When these errors were corrected there were enhancements of hazard. The Minority Report also states that the Committee had accepted that a 1 micrometre plutonium particle would give a track rate so high that each cell within range of the decays would receive a second event in a year. According to the Minority Report, this inevitably meant that there is a particle size which would provide second events at very high efficiency at doses too small to kill the cells. A study presented to the Committee but not reported by it showed synthetic beta-emitting particles in mice produced more mutation than alpha-emitting particles, contrary to ICRP expectations based on Relative Biological Effectiveness. The Minority Report states
The CERRIE Minority Report states, contrary to the Majority Report, that the review of Strontium-90 studies which the Committee commissioned to investigate the plausibility of the Second Event theory did find studies compatible with the theory, as well as some that were incompatible with it. "In addition", the Minority Report says, "the review left out some studies which showed such effects." Alpha emittersThe published work of Chris Busby includes an assertion that a hot particle of 239Pu is able to subject the biologcal tissues to a series of alpha particles. He suggests that this is one of the reasons why hot particles are able to cause health effects. In the CERRIE Minority Report (page 68) he writes:
A cheap detection techniqueFor people who are interested in testing environmental samples for the presence of alpha emitting substances such as Plutonium and Uranium LLRC advises a method based on plastic sheet [39]. This is widely used for the measurement of radon gas and other alpha emitters. CR39, a plastic sheet which is damaged by the action of alpha particles, is exposed to the samples and then etched with sodium hydroxide (a strong base). It is examined by optical microscopy. The methodology is inexpensive and robust and can be used by citizen groups. Preexposure to radiation with regards to acute health effects and other good effectsSome studies have suggested that preexposure to radiation exerts a protective effect upon cells [43] and whole animals[44]. In mice it has been shown that a 200 mGy X-ray dose protects mice against both further X-ray exposure and ozone gas.[45] Furthermore it has been shown in a rodent study that low level (1 mGy hr-1) gamma irradiation prevents the development of cancer (induced by chemical means, injection of methylcholanthrene).[46] Also it has been shown that irradiation with gamma rays increases the concentration of glutathione (an antioxidant) found within cells, this is likely to lead to an adaptive response.[47] While it is clear that a large single exposure to plutonium dioxide powder is able to cause a fatal lung cancer in monkeys (and thus it is likely that PuO2 powder is carcinogenic in humans),[48] some studies have shown that moderate internal exposure to plutonium results in a reduction of the risk of getting cancer,[49]. Other studied have suggested that a small dose of radiation may be good for you.[50] However one explanation for this effect is the fact that the majority of radiation workers are subject to greater number of health checks than the general population, and thus as a result any sign of disease is more likely to be seen at an early (curable) stage. Also see the "healthy worker hypothesis". In plants radiation hormesis has been observed[51] However the existence of radiation hormesis in humans has been questioned, it is reasonable to state that for late effects (such as cancer) that the scientific community has not come to an agreement regarding this matter.[40] But in one recent case it was claimed (In Journal of American Physicians and Surgeons) that the persons living in a apartment block in Taiwan which was constructed using concrete which contained rebar contaminated with cobalt-60 experience a better state of health than the average person.[52] Cadmium poisoning as a modelIt is known that many toxic metals can induce oxidative stress in tissue which may result in free radical induced damage. Also it is known that prior exposure to a small dose of cadmium can mitigate the effects of a second larger dose, this suggests that the first lower dose of the poison stimulates the DNA repair processes in the exposed tissue.[53][54][55][56] References
Categories: Radiation health effects | Radiobiology |
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This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "The_Low_Level_Radiation_Campaign". A list of authors is available in Wikipedia. |