Greens to issue radiation risk study

["Jim Hoerner" <jim_hoerner@HOTMAIL.COM>]

[Two snippets on the subject - JH]



Washington (Nuclear News Flashes)--30Jan2003



Radioactive releases up to 1989 will cause 65-million deaths worldwide in 

total, a report commissioned by Greens in the European Parliament 

(EP)claims. The report, to be released Jan. 31 in Brussels, is by the 

European Committee on Radiation Risk (ECRR), which was instructed to ignore 

all previous scientific studies and reconsider radiation releases and their 

relation to human diseases. Sponsoring Greens specifically rejected claims 

that low radiation doses were not harmful and dismissed all previous studies 

that did not find a link between increased cancer incidence and radiation. 

According to the EP Greens, the ECRR study "uses a new risk assessment model 

developed over the last five years" and "concludes that the present cancer 

epidemic is a result of pollution from nuclear energy and of exposures to 

global atmospheric weapons fallout, which peaked in the period 1959-63." 

Green MEP Caroline Lucas said previous studies finding releases didn't cause 

cancer clusters "was more a reflection on the research methodology than the 

acclaimed safety" of nuclear. The study was funded by the Pew oundation and 

environmental group Bellona.



http://www.platts.com/stories/nuclear2.html



-----



Executive Summary at

http://www.euradcom.org/2003/execsumm.htm



[Check out item 12 below.  It was last on the list, but probably the first 

thing written, if you know what I mean.  See my next post to Know_Nukes at 

http://groups.yahoo.com/group/Know_Nukes/messages for my very brief comments 

on the subject.  Probably post number 8284. - JH ]



ECRR 2003 Recommendations of the European Committee on Radiation Risk The 

Health Effects of Ionising Radiation Exposure at Low Doses for Radiation 

Protection Purposes. Regulators' Edition.



Executive Summary



This report outlines the committee's findings regarding the effects on human 

health of exposure to ionising radiation and presents a new model for 

assessing these risks. It is intended for decision-makers and others who are 

interested in this area and aims to provide a concise description of the 

model developed by the committee and the evidence on which it depends. The 

development of the model begins with an analysis of the present risk model 

of the International Commission on Radiological Protection (ICRP) which is 

the basis of and dominates all present radiation risk legislation. The 

committee regards this ICRP model as essentially flawed as regards its 

application to exposure to internal radioisotopes but for pragmatic reasons 

to do with the existence of historical exposure data has agreed to adjust 

for the errors in the ICRP model by defining isotope and exposure specific 

weighting factors for internal exposures so that the calculation of 

effective dose (in Sieverts) remains. Thus, with the new system, the overall 

risk factors for fatal cancer published by ICRP and other risk agencies may 

be used largely unchanged and legislation based upon these may also be used 

unchanged. It is the calculation of the dose which is altered by the 

committee's model.



1. The European Committee on Radiation Risk arose out of criticisms of the 

risk models of the ICRP which were explicitly identified at the European 

Parliament STOA workshop in February 1998; subsequently it was agreed that 

an alternative view should be sought regarding the health effects of low 

level radiation. The committee consists of scientists and risk specialists 

from within Europe but takes evidence and advice from scientists and experts 

based in other countries.



2. The report begins by identifying the existence of a dissonance between 

the risk models of the ICRP and epidemiological evidence of increased risk 

of illness, particularly cancer and leukaemia, in populations exposed to 

internal radioactive isotopes from anthropogenic sources. The committee 

addresses the basis in scientific philosophy of the ICRP risk model as 

applied to such risks and concludes that ICRP models have not arisen out of 

accepted scientific method. Specifically, ICRP has applied the results of 

external acute radiation exposure to internal chronic exposures from point 

sources and has relied mainly on physical models for radiation action to 

support this. However, these are averaging models and cannot apply to the 

probabilistic exposures which occur at the cell level. A cell is either hit 

or not hit; minimum impact is that of a hit and impact increases in 

multiples of this mimimum impact, spread over time. Thus the committee 

concludes that the epidemiological evidence of internal exposures must take 

precedence over mechanistic theory-based models in assessing radiation risk 

from internal sources.



3. The committee examines the ethical basis of principles implicit in the 

ICRP models and hence in legislation based on them. The committee concludes 

that the ICRP justifications are based on outmoded philosophical reasoning, 

specifically the averaging cost-benefit calculations of utilitarianism. 

Utilitarianism has long been discarded as a foundation for ethical 

justification of practice owing to its inability to distinguish between just 

and unjust societies and conditions. It may, for example, be used to 

underpin a slave society, since it is only the overall benefit which is 

calculated, and not individual benefit. The committee suggests that 

rights-based philosophies such as Rawls Theory of Justice or considerations 

based on the UN Declaration of Human Rights should be applied to the 

question of avoidable radiation exposures to members of the public resulting 

from practice. The committee concludes that releases of radioactivity 

without consent can not be justified ethically since the smallest dose has a 

finite, if small, probability of fatal harm. In the event that such 

exposures are permitted, the committee emphasises that the calculation of 

'collective dose' should be employed for all practices and time scales of 

interest so that overall harm may be integrated over the populations.



4. The committee believes that it is not possible accurately to determine 

'radiation dose to populations' owing to the problems of averaging over 

exposure types, cells and individuals and that each exposure should be 

addressed in terms of its effects at the cell or molecular level. However, 

in practice, this is not possible and so the committee has developed a model 

which extends that of the ICRP by the inclusion of two new weighting factors 

in the calculation of effective dose. These are biological and biophysical 

weighting factors and they address the problem of ionisation density or 

fractionation in time and space at the cell level arising from internal 

point sources. In effect, they are extensions of the ICRP's use of radiation 

weighting factors employed to adjust for differences in ionisation density 

resulting from different quality radiations (e.g. alpha-, beta and gamma).



5. The committee reviews sources of radiation exposure and recommends 

caution in attempting to gauge the effects of novel exposures by comparison 

with exposures to natural radiation. Novel exposures include internal 

exposures to artificial isotopes like Strontium-90 and Plutonium-239 but 

also include micrometer range aggregates of isotopes (hot particles) which 

may consist of entirely man-made isotopes (e.g. plutonium) or altered forms 

of natural isotopes (e.g. depleted uranium). Such comparisons are presently 

made on the basis of the ICRP concept of 'absorbed dose' which does not 

accurately assess the consequence for harm at the cell level. Comparisons 

between external and internal radiation exposures may also result in 

underestimates of risk since the effects at the cell level may be 

quantitatively very different.



6. The committee argues that recent discoveries in biology, genetics and 

cancer research suggest that the ICRP target model of cellular DNA is not a 

good basis for the analysis of risk and that such physical models of 

radiation action cannot take precedence over epidemiological studies of 

exposed populations. Recent results suggest that very little is known about 

the mechanisms leading from cell impact to clinical disease. The committee 

reviews the basis of epidemiological studies of exposure and points out that 

many examples of clear evidence of harm following exposure have been 

discounted by ICRP on the basis of invalid physical models of radiation 

action. The committee re-instates such studies as a basis for its estimates 

of radiation risk. Thus the 100-fold discrepancy between the ICRP model's 

predictions and the observed cases in the Sellafield childhood leukemia 

cluster becomes an estimator of risk for childhood leukemia following such 

exposure. The factor is thus incorporated by the committee into the 

calculation of harm from internal exposure of specific types through its 

inclusion in the weighting factors used to calculate the 'effective dose' to 

the children in Sieverts.



7. The committee reviews the models of radiation action at the cell level 

and concludes that the 'linear no threshold' model of the ICRP is unlikely 

to represent the response of the organism to increasing exposure except for 

external irradiation and for certain end points in the moderately high dose 

region. Extrapolations from the Hiroshima lifespan studies can only reflect 

risk for similar exposures i.e. high dose acute exposures. For low dose 

exposures the committee concludes, from a review of published work, that 

health effects relative to the radiation dose are proportionately higher at 

low doses and that there may be a biphasic dose response from many of these 

exposures owing to inducible cell repair and the existence of 

high-sensitivity phase (replicating) cells. Such dose-response relationships 

may confound the assessment of epidemiological data and the committee points 

out that the lack of a linear response in the results of epidemiological 

studies should not be used as an argument against causation.



8. In further considering mechanisms of harm, the committee concludes that 

the ICRP model of radiation risk and its averaging methods exclude effects 

which result from anisotropy of dose both in space and in time. Thus the 

ICRP model ignores both high doses to local tissue caused by internal hot 

particles, and sequential hits to cells causing replication induction and 

interception (second event), and merely averages all these high risk 

situations over large tissue mass. For these reasons, the committee 

concludes that the unadjusted 'absorbed dose' used by ICRP as a basis of 

risk calculations is flawed, and has replaced it with an adjusted 'absorbed 

dose' which used enhancement weightings based on the biophysical and 

biological aspects of the specific exposure. In addition, the committee 

draws attention to risks from transmutation from certain elements, notably 

Carbon-14 and Tritium, and have weighted such exposures accordingly. 

Weightings are also given to radioactive versions of elements which have a 

particular biochemical affinity for DNA e.g. Strontium and Barium and to 

certain Auger emitters.



9. The committee reviews the evidence which links radiation exposure to 

illness on the basis that similar exposures define the risks of such 

exposures. Thus the committee considers all the reports of associations 

between exposure and ill health, from the A-bomb studies to weapons fallout 

exposures, through nuclear site downwinders, nuclear workers, reprocessing 

plants, natural background studies and nuclear accidents. The committee 

draws particular attention to two recent sets of exposure studies which show 

unequivocal evidence of harm from internal irradiation at low dose. These 

are the studies of infant leukemia following Chernobyl, and the observation 

of increased minisatellite DNA mutations following Chernobyl. Both of these 

sets of studies falsify the ICRP risk models by factors of between 100 and 

1000. The committee uses evidence of risk from exposures to internal and 

external radiation to set the weightings for the calculation of dose in a 

model which may be applied across all exposure types to estimate health 

outcomes. Unlike the ICRP the committee extends the analysis from fatal 

cancer to infant mortality and other causes of ill health including 

non-specific general health detriment.



10. The committee concludes that the present cancer epidemic is a 

consequence of exposures to global atmospheric weapons fallout in the period 

1959-63 and that more recent releases of radioisotopes to the environment 

from the operation of the nuclear fuel cycle will result in significant 

increases in cancer and other types of ill health.



11. Using both the ECRR's new model and that of the ICRP the committee 

calculates the total number of deaths resulting from the nuclear project 

since 1945. The ICRP calculation, based on figures for doses to populations 

up to 1989 given by the United Nations, results in 1,173,600 deaths from 

cancer. The ECRR model predicts 61,600,000 deaths from cancer, 1,600,000 

infant deaths and 1,900,000 foetal deaths. In addition, the ECRR predict a 

10% loss of life quality integrated over all diseases and conditions in 

those who were exposed over the period of global weapons fallout.



12. The committee lists its recommendations. The total maximum permissible 

dose to members of the public arising from all human practices should not be 

more than 0.1mSv, with a value of 5mSv for nuclear workers. This would 

severely curtail the operation of nuclear power stations and reprocessing 

plants, and this reflects the committee's belief that nuclear power is a 

costly way of producing energy when human health deficits are included in 

the overall assessment. All new practices must be justified in such a way 

that the rights of all individuals are considered. Radiation exposures must 

be kept as low as reasonably achievable using best available technology. 

Finally, the environmental consequences of radioactive discharges must be 

assessed in relation to the total environment, including both direct and 

indirect effects on all living systems.





--

Hold the door for the stranger behind you.  When the driver a 

half-car-length in front of you signals to get over, slow down.  Smile and 

say "hi" to the folks you pass on the sidewalk.  Give blood.  Volunteer.







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