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17/09/2008 - RRT Conference 2008
Contents
[Introduction]
[The precautionary principle and public policy]
[ICNIRP, WHO, and international guidance]
[Issues raised by the ICNIRP approach to risk assessment]
[The speakers, their presentations and contributions]
[Powerwatch conclusions]
Introduction
The Radiation Research Trust organised conference "EMF & Health - A Global Issue ... Exploring appropriate precautionary approaches" was held on the 8th & 9th September 2008 and was extraordinarily successful. Collecting some highly prominent speakers from world establishments such as ICNIRP, WHO, RNCNIRP and national bodies such as the UK Health Protection Agency and the MTHR, the conference has brought together differing viewpoints with an excellent opportunity for dialogue. Alongside these representatives were a number of high profile and well respected scientists, including 5 of the authors of the BioInitiative report.
The conference was extremely well organised and produced a number of fascinating and informative presentations on a wide variety of issues related to electromagnetic radiation, public health policy decision making processes and how the two inter-relate, raising a number of issues that are in urgent need of addressing. The majority of this article will cover those issues, their implications, and possible ways forward. For a brief synopsis of the contents of individual presentations, please see The speakers, their presentations and contributions section below.
The precautionary principle and public policy
The European Parliament have made their feelings on the adequacy of current guidelines very clear, especially with regards to acquiring the information required to appropriately set public policy:
21. Is greatly concerned at the Bio-Initiative international report concerning electromagnetic fields, which summarises over 1500 studies on that topic and which points in its conclusions to the health risks posed by emissions from mobile-telephony devices such as mobile telephones, UMTS, Wifi, Wimax and Bluetooth, and also DECT landline telephones;
22. Notes that the limits on exposure to electromagnetic fields which have been set for the general public are obsolete, since they have not been adjusted in the wake of Council Recommendation 1999/519/EC of 12 July 1999 on the limitation of exposure of the general public to electromagnetic fields (0 Hz to 30 GHz), obviously take no account of developments in information and communication technologies, of the recommendations issued by the European Environment Agency or of the stricter emission standards adopted, for example, by Belgium, Italy and Austria, and do not address the issue of vulnerable groups, such as pregnant women, newborn babies and children;
23. Calls, consequently, upon the Council to amend its Recommendation 1999/519/EC in order to take into account the Member States' best practices and thus to set stricter exposure limits for all equipment which emits electromagnetic waves in the frequencies between 0.1 MHz and 300 GHz;"
European Parliament resolution of 4 September 2008 on the mid-term review of the European Environment and Health Action Plan 2004-2010 - view full resolution
The difficulty is that the ICNIRP guidelines, in their current form (since 1998), cover only thermal and electric shock effects from electromagnetic radiation. With a large number of peer-reviewed papers coming out every year hinting at effects on leukaemia[Ahlbom 2000, Greenland 2000, Tynes 2003, O'Carroll 2008], brain cancer[Lonn 2004, Hardell 2006, Hardell 2007, Hours 2007], fertility[Grajewski 2000, Fejes 2005, Erogul 2006, Agarwal 2008, Baste 2008], neurogenerative diseases (such as Alzheimer's and amyotrophic lateral sclerosis)[Feychting 2003, Hakansson 2003, Ahlbom 2001, Garcia 2008], EEG and neurological effects[Preece 2005, Oktay 2006, Hung 2007] and genotoxicity and cell signalling effects[Rao 2008, Schwarz 2008, George 2008], and a plethora of other biological and health endpoints (from either RF or ELF exposure), these guidelines appear to be largely out of date, making it very difficult for public policy makers to accurately assess the viability of different risk management strategies and their likely benefits. Sadly, from what was said at the conferences, "updating" the guidelines to include non-thermal effects is unlikely to be successful due to the assessment criteria by which the guidelines are established.
ICNIRP, WHO, and international guidance
With both Mike Repacholi and Paolo Vecchia talking candidly about their opinions, their personal approaches and the assessment of science used to formulate guidelines, it became very clear that there was a serious gap in addressing areas of scientific uncertainty. For example, Paolo Vecchia explained that ICNIRP guidelines were set to provide protection against scientifically "established" effects, and established effects only. Associations between EMFs and health effects such as cancers are discussed in ICNIRP documentation, but until the association is considered causal no attempt will be made to adjust the guidelines to cater for them.
To reach the status of an established effect, he explained that the supporting research must be peer-reviewed, replicated by separate research groups, consistently find the same effects at approximately the same magnitude, and show a clear mechanistic cause and effect. All four criteria must be fully met before an association can meet the subjectively defined criteria.
Mike Repacholi explained that, for the purposes of defining causal mechanism, there are four separate scientific stages: physics (atomic and molecular interactions with forces), chemical (intracellular interactions between atomic and molecular entities with each other), biological (intercellular interactions, such as nerve signalling pathways, bystander effects etc), and then finally how these interactions then manifest themselves as health effects. He explained that unless all (or at least most) of these stages can be identified, a causal relationship cannot be accepted. Without this, it is not possible to view the association as an established effect.
Neither of these two speakers denied that there was evidence that there may be health effects far below these guidelines, but made it very clear that until the evidence was sufficiently strong to be causal it was a) not appropriate to use the evidence in the context of setting guidance levels, and b) not appropriate to present the evidence to public policy makers whilst uncertainty that remains. The idea of presenting more than one possibility and possible preventative measures with associated estimated levels of certainty was considered to be outside of their remit. This view was supported by Anders Ahlbom, and Mike Dolan said that policy makers expect one clear outlook that they can perceive as the "truth" that they can act on, and would not accept a document with multiple potential outcomes. The MPs present at the conference felt that this was unlikely, stating that they'd rather make a decision on more complete information than just be given one option.
By this criteria, it is clear for both ICNIRP and WHO to accept and publish an association between EMFs and a number of health effects, the certainty that the association is causal must be extremely high, in the region of 95 to 98% chance. It is worth bearing in mind that risk factors for smoking, asbestos, thalidomide, lead in petrol etc. would not have been identified using these criteria. This does not mean that they are an invalid approach per se, as it is very important to have assessment criteria for establishing effects that are beyond reasonable doubt, but it is next to useless for policy makers who are attempting to pre-empt large scale health catastrophes by making risk management judgements in areas of scientific uncertainty. Whilst proportionality is a crucial factor, it is not for risk assessors to decide to withhold significant information from public risk managers because of lack of "full scientific certainty". Indeed, the EU's acceptance of the Precautionary Principle requires that public risk managers are made aware of reasonable concerns where harm may occur but where there is still considerable scientific uncertainty.
Issues raised by the ICNIRP approach to risk assessment
There are a number of information shortfalls generated by only having this limited approach:
Biological mechanisms
For both RF and ELF effects, there are a number of peer-reviewed, replicated consistently reached endpoints that are failing causal recognition under the basis of not having an established mechanism. This is importantly different to "plausible mechanism", for which there are a number for both ELF fields[Henshaw 2002, Henshaw & Reiter 2005, Binhi 2008, Blank 2008] and RF fields[Nylund 2006, Friedman 2007, Roux 2007, Sheppard 2008], that are requiring further investigation and confirmation (or otherwise). It is clear that confirming any mechanism is considered highly important, as it is the primary (though not sole) reason for ELF EMFs to have an IARC "2B" classification as only a "possible" carcinogen whereas other causative agents such as passive smoking (for which the epidemiological evidence is relatively weak) has an IARC "1" classification.
ELF EMFs and health endpoints
Looking through WHO's Factsheet 322, one would be forgiven for thinking that an association between ELF EMFs and childhood leukaemia is tenuous at best, damaged by lack of mechanistic support and other flaws such as selection bias. Considering the references given above (the Greenland meta-analysis virtually ruled out selection bias as being sufficient to explain the increase by statistical calculation) this is a very conservative summary, and is full of subjective assumptions. It then continues to largely discount other associations: "The WHO Task Group concluded that scientific evidence supporting an association between ELF magnetic field exposure and all of these health effects is much weaker than for childhood leukaemia. In some instances (i.e. for cardiovascular disease or breast cancer) the evidence suggests that these fields do not cause them". The final sentence, purely by human nature of having read it last gives the implied impression that the associations for other health effects are too weak for consideration, again dispite the references mentioned above and the assessments of other scientific groups such as the California EMF project and the BioInitiative group. The attributable fraction is also only considered for Childhood Leukaemia, without any assessment for what the fraction would increase to if other health outcomes were considered (something which the UK SAGE stakeholder group considered in their "CL+" case). This lack of alternative scenarios being presented to public policy making bodies means that a very one-sided view of ELF science is presented, which makes accurate risk management decisions very hard to evaluate.
Base Stations, exposure levels and causality
WHO cover base stations and exposures on their Factsheet 304, which again has serious limitations in breadth due to self-imposed scientific assumptions. By assuming that the considerably lower absorbed dose when compared to handset usage or TV / Radio transmission would mean that the effects would be seen in the other exposures first (this assumption expects some form of linear dose-response relationship, something which has not been consistently observed in the RF literature to date). This therefore writes off the likelihood of health effects from base stations without openly considering the majority of base station peer reviewed epidemiological research finding consistent increases in somatic symptoms and cancer as being, in themselves, sufficient to warrant funding for further research. Again, this is only one viewpoint, and due to the reliance on WHO and ICNIRP for EMF advice, other scientifically justified viewpoints are not reaching public policy makers, preventing them from making more proportionally appropriate risk management decisions.
All of the above cases lead to a severe lack of sufficient information being available to policy makers. It is the equivalent at refusing to identify the possible picture in a jigsaw puzzle when it is missing 15% of its pieces. It is vital that there are new assessment criteria drawn up, either by a new body or existing body, that can address scientific uncertainty, including the nature of plurality in risk assessment (catering with multiple possible outcomes and differing risk assessments for each outcome), so that public policy making and advisory bodies can be fully provided with sufficiently detailed information to make adequately informed decisions.
The speakers, their presentations and contributions
The following is a brief synopsis of what we consider each speaker covered in their talk at the conference. Because these comments are very brief, they are just our gist of what we heard them say.
Day 1
Sir William Stewart explained why he felt the conference was so important, gave the basis from which the IEGMP (Stewart) report was written, an overview of other projects (such as Interphone, with a query as to why the results still weren't published). He also raised the query of how best to incorporate documents such as the BioInitiative report, and the important in dialogue to enable both sides to develop a way forward, including understanding why views are different and how to either a) harmonise those views or b) present differing views with different levels of certainty and different outcomes. He highlighted the importance of dumping the notion that the outcome can be disregarded if there is no established mechanistic support, and that using "psychological effects" as a write off is inappropriate without sufficient evidence showing a strong association specifically looking for psychological effects. People and their symptoms need to be put first and we should seek and test possible causal explantions. He empasised we should use the tools of genetic profiling and molecular epidemiology and stated "the book is not closed - we need to keep an open mind."
Michael Repacholi covered the WHO approach to the assessment of science, and why publicly available information is presented the way it is. He mentioned the difference between risk assessment (scientific evaluation of data) and risk management (policy makers' strategic decison making based on provided data), and how WHO and ICNIRP fit into the bigger picture. He pointed out that 90% of 16 year-olds in the UK have their own mobile phone and 10% use them for over 45 minutes every day. He aso stated that, in his opinion, active smoking is the worst health hazard and the use of mobile phones is "not a health issue."
David Carpenter presented and countered a number of commonly claimed fallacies involving electromagnetic radiation, and gave a detailed explanation as to why these are either untrue or misleading. He explained that we do not know what causes either Alzheimer Disease nor ALS (motor neurone disease) and that the strongest evidence of a causal relationship is with power-frequency magnetic field exposure. He also said that, as brain tumours have a 20 to 30 year latency, that we should not yet expect to see, if there is to be one, a significant rise from mobile phone use. He summarised the BioInitiative recommended standards which he claimed had taken into account uncertain low level effects that are now being consistently reported in the literature.
Anders Ahlbom spoke in great detail about the separation between risk assessment and risk management. He defined evaluation principles for research (design, methodology, strength, consistency of results), and that each study's value was weighted based on a subjective assessment of these criteria. He repeatedly commented that scientists are responsible for risk assessment (ideally with one agreed risk evaluation), that policy makers are responsible for risk management, and that these roles should not mix.
Henry Lai covered the great depth of research over the last 15 years finding genetic, reproductive, brain cell / physiology effects and free radical involvement, including the possibility that pulse modulation was vital for effects to occur. He covered over 100 scientific citations, and introduced the possibility that a large impact on the cellular effects may be generated by the interaction between the fenton reaction and EMFs (due to its involvement with iron).
Zenon Sienkiewicz gave a very lively and enjoyable presentation. He addressed the Health Protection Agency's approach to science, uncertainty and public policy. Mentioning that rigorously applied attention to scientific approaches helps to quantify the level uncertainty. However, when mentioning the setting of guidelines he deferred to the ICNIRP assessment (mentioned above), and did not address any issues of how (or even whether) scientific uncertainty affects their policy advice.
Lennart Hardell covered a large amount of his epidemiological work showing a very consistent trend of increased ipsilateral risk for long term phone usage for a number of brain tumours (benign and malignant). He also highlighted that the age group at first use is highly significant (5 fold increase in glioma risk for those starting mobile phone use under 20 years of age). Finally he covered the strongly consistent protective effect across the Interphone studies, casting doubt on the credibility of the Interphone protocol.
David Coggan commented that the MTHR review (2007) adjusted research priorities, lowering the importance of short term mobile use on brain tumours, RF effects on brain function, and, inexplicably, biological mechanisms and exposures from mobile phone base stations. This was made even more controversial by a summary statement that there were "fewer pressing research needs than in 2001", despite the preponderence of evidence suggesting the reverse may be the case.
Brian Stein gave a heartfelt description of the last 15 years of his life, from a happy and heavy corporate mobile phone user to someone who cannot drive a modern car or use modern electrical appliances. He covered some of the key flaws in provocation studies and their selection and methods, and explained why he was unable (despite the severity of his condition) to participate in the UK studies and how similar issues have rendered their results unlikely to reflect the real ES situation in the UK.
Olle Johansson covered a large amount of his work showing objective differences between sensitive and non-sensitive subjects such as skin cell differences, and outlined the existing situation in Sweden and how this reflects on EU standards of human rights. Some interesting questions were raised, such as whether people with a fully acceptable impairment in Sweden would find it written off as psychological should they travel to the UK, and whether this was contrary to their human rights. He highlighted the extreme lack of funding for properly investigating electrosensitivity issues.
James Rubin outlined much of the existing work into electrosensitivity double blind provocation studies. From a brief outline of what they were and why they were carried out, he gave a synopsis of the work to date. He then gave an excellent and detailed overview of existing possible flaws with comments as to their plausibility and impact, and the conclusions that could and could not be drawn from the results. He also presented an important caveat on the potential risks of unnecessary precaution that needed to be considered when generating public policy.
Michael Landgrebe and Ulrich Frick jointly presented their own research, finding objective differences between the responses of sensitive and non-sensitive partipants to very high levels of magnetic fields (>1 Tesla!). They summarised two very interesting findings: a) that sensitive participants are less able to differentiate between high and low field levels, and that b) there is a replicable physiological effect in sensitive participants even when no field is present (but the participants are told that there is). They are making important new contributions to the investigations into ES.
Grahame Blackwell gave a very thought provoking presentation and showed how there are numerous examples in the last 30 years where science has considered areas to be fully explored and understood and yet then challenged and subsequently proved that the reality is either different or more complex than previously understood. With comparisons between light and photons and their possible applicability to EMFs (currently not considered) to other existing non-thermal uses of electromagnetic fields, he clearly presented the need to keep an open mind to EMF science. Many delegates expressed their approval of his thought-stimulating talk, the slides and notes of which are available as a pdf, or as a full .ppt presentaion from his website.
Day 2
Laurent Bontoux demonstrated the framework under which the European Commission deals with consumer safety on a wide range of products from food to drugs, and how they apply similar principles to the adoption of appropriate guidance with regards to EMFs. He was very clear that, as with ICNIRP and WHO, guidance should be set purely on established effects, and limited certainty lower level effects needed further confirmation before they could be incorporated into European guidance. His talk was very helpful for us to understad the official EU decision processes.
Mike Dolan covered the legal history of the application of the precautionary principle. Highlighting that the principle cannot be applied on mere speculation, he raised the important concept of how much evidence is required. The principle may recommend actions from halting all activity to doing almost nothing dependend on severity of prevalence and evidence of an effect, and that incorporating proportionality into management decisions is vital. He didn't comment on how existing mobile phone science fitted into the picture, other than referring to international reviews that conclude there are no 'established' effects (i.e. not commenting on recognised but uncertain effects).
George Carlo discussed the concept of post market surveillance. He highlighted the importance for all industries to not only do pre-market clinical trials (which are naturally limited, but from which the mobile phone industry was excluded), but also have a responsibility to follow up on consumers post market release to monitor the effects. This, as with the trials, has not been done with mobile phones, leaving epidemioligical science to play "catch up" in an increasingly saturated market. He commented in some detail that studies analysing objective biological markers are now essential.
Lloyd Morgan produced a continuation of the evidence demonstrated in his column on this site, covering 9 separately assessed flaws in the Interphone protocol, of which 8 lead to a clear underestimation in risk. With the findings of the Interphone papers demonstrating such a statistically significant protective use from light mobile phone use (incidentally an effect that disappears at heavier usage), the flaws leave only two possibilities: 1) that phones actually protect the user from harm (which considering the heavier use scenario is unlikely), or that 2) the flaws are sufficiently strong to invalidate the project's data. He asked the vital question as to why the many Interphone studies published to date with statistically significant "protective" effect have not actually properly discussed this issue within their paper - in fact they have generally ingored the significance of their "protective" result. [View presentation].
Paolo Vecchia explained that ICNIRP guidelines were set to provide protection against scientifically "established" effects, and established effects only. Associations between EMFs and health effects such as cancers are discussed in ICNIRP documentation, but until the association is considered causal no attempt will be made to adjust the guidelines to cater for them. He then explained that to reach the status of an established effect, he explained that the supporting research must be peer-reviewed, replicated by separate research groups, consistently find the same effects at approximately the same magnitude, and show a clear mechanistic cause and effect. All four criteria must be fully met before an association can meet the subjectively defined criteria.
Gerd Oberfeld covered a the precationary policies adopted by a number of other European countries, either as national policy or as advisory guidelines, and the basis under which these were set. He highlighted the need for differentiation between chronic and acute exposure, residential and occupational guidance, and electric and magnetic fields for both ELF and RF radiation. It was clear that some policy makers are more than prepared to set guidelines based on the existence of uncertainty in science provided that the information is actually supplied to them.
Yuri Grigoriev gave a good background of Russian standards and advisory guidelines, how they are set and how they compare with other international guidance such as those from ICNIRP, IEEE and CENELEC. He explains how a number of unsupportable assumptions lead to the conclusion that if there are no effects (such as cancer) at high exposure levels, there can't be any at lower levels, and explained that low level effects need assessing in their own right, even if the mechanisms are unknown. He described the unknown quantities (such as whether dose accumulation, pulse modulation, accumulation of different frequencies and other issues were necessarily relevant) and that children must be considered very separately to adults, as they are likely to be at greater risk.
Maila Hietanen summarised the number of provocation studies to date looking at provocation studies on base station exposure, and how the mixed results make it very hard to draw clear conclusions, but that more research is definitely required.
Michael Kundi gave an overview of base station research to date, of which the majority (10 out of 14 peer-reviewed studies) both found significant increases in the symptoms being analysed, and conformed to the specified WHO / ICNIRP standards of scientific quality, including their assessment criteria of consistency and replication. He stressed that directing scientific funding away from base station exposure investigations (and looking only at handsets first) was completely unscientific and inappropriate in the light of existing findings. Lack of understood mechanism is not an argument for not funding scientific research. He highlighted the difference between known hazards and the need for prevention, and possible hazards and the need for precaution - highlighting that both were essential approaches.
In probably the most novel presentation of the conference, Ulrich Warnke presented experimental data showing how electromagnetic systems can affect living systems in existing animal models, especially in bird and bee navigation (including an example of research where DECT transmissions prevented bees from being able to find their way back to their hive). He presented a number of mechanisms (theoretical, but with experimental support) showing possible ways in which these systems could be affected by electromagnetic fields, and concluded that there are a number of other frequencies involved due to the modulated nature of mobile telecommunication signals that could have a large effect on neurological and cellular processes via existing known mechanisms. We have made a recently translated publication of his work available.
Mike O'Carroll explained the importance of plurality in scientific risk assessment - that of respecting multiple different criteria for assessing science, leading to different interpretaions and differing risk assessments that can be considered as equally valid. It is important that bodies with differing conclusions openly discuss their differences of approach, but policy procedures should allow for these differing viewpoints when updating policies, especially with regards to preventative and precautionary approaches.
Emilie Van Deventer, the new head of the WHO EMF Project, started by drawing an interesting parallel between public concern over mobile phone usage and sunbed usage, comparing the exposures to their known risks - an interesting point in proportionality. She covered risk assessment and risk managements strategies and how they fall into the bigger picture, and included the public "risk perception" and how that needs to be incorporated. She then described the existing projects, what they hope to achieve, and what the future objectives are for WHO's research into electromagnetic radiation which always struggles to find funding.
Cindy Sage covered the issues of how to decide on what standard of evidence is required for any given choice of action. Highlighting that whilst in science a certainty of 95%+ is required before guidance is offered, in other areas this value is considerably lower, and with regards to environmental pollutants can be as low as 10-30% certainty before some level of precaution is appropriate, especially when the impact may be significant. The evidence sought should be adjusted by taking into account the possible risk of inaction should the risks prove to be true, and provided a number of possible precautionary steps that can be taken in the light of scientific uncertainty (such as using alternative forms of communication devices) without the need to state a risk is causal. This was discussed in the BioInitiative report (see especially Section 16, page 15).
Powerwatch conclusions
The conference has brought together speakers and organisations that are internationally recognised as having expertise in both electromagnetic radiation research and how this applies to public policy and precaution. It has raised a number of very important issues, primarily one of an enormous gap in the presentation of uncertain science - something entirely inappropriate for college science textbooks but utterly essential for the proportional risk management decision making processes faced by governments and state bodies responsible for setting national and local guidelines.
References
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8. -
Hours M et al, (October 2007) Cell Phones and Risk of brain and acoustic nerve tumours: the French INTERPHONE case-control study, Rev Epidemiol Sante Publique. 2007 Oct;55(5):321-32 [ View Author's abstract conclusions] [ View
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Hakansson N et al, (July 2003) Neurodegenerative diseases in welders and other workers exposed to high levels of magnetic fields, Epidemiology. 2003 Jul;14(4):420-6; discussion 427-8 [ View Author's abstract conclusions] [ View
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Schwarz C et al, (May 2008) Radiofrequency electromagnetic fields (UMTS, 1,950 MHz) induce genotoxic effects in vitro in human fibroblasts but not in lymphocytes, Int Arch Occup Environ Health. 2008 May;81(6):755-67 [ View Author's abstract conclusions] [ View
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Binhi V, (July 2008) Do naturally occurring magnetic nanoparticles in the human body mediate increased risk of childhood leukaemia with EMF exposure?, Int J Radiat Biol. 2008 Jul;84(7):569-79 [ View Author's abstract conclusions] [ View
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Nylund R, Leszcynski D, (September 2006) Mobile phone radiation causes changes in gene and protein expression in human endothelial cell lines and the response seems to be genome- and proteome-dependent, Proteomics 2006 Sep;6(17):4769-80 [ View Author's abstract conclusions] [ View
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