30/01/2008 - HPA issues flawed information to local council
On the 12th of December 2007 the Health Protection Agency wrote a formal letter to the Vale of White Horse District Council (Abingdon, Oxfordshire) that presented a highly misleading interpretation of current EMF science.
The letter sets out to attack reasoning in a report from an independent engineering company (WSP UK:Environmental) who surveyed the site and gave precautionary advice on extremely low frequency electromagnetic field (ELF EMF) exposure as per recent evidence and recommendations (including from SAGE). They suggested some firm, but reasonable, precautionary guidance.
It is highly disappointing that a UK agency designed to protect the health of the British public can continue to dismiss the powerful evidence (that is steadily increasing - indeed, it is accelerating) that a precautionary approach to electromagnetic fields is very long overdue. The HPA could easily have answered the Council query in a short letter stating that as the distance between the proposed new houses and the HVOTL exceeded the 60 metres suggested by SAGE as being appropriately precautionary, without resorting to incorrect statements about science and personal attacks. We have taken a number of paragraphs out of the letter for further comment:
"In the report, WSP Environmental UK recommend a precautionary approach based on the epidemiological observation that time-weighted average exposures above 0.4 µT is associated with a small increase in the absolute risk of leukaemia in children from about 1 in 20,000 to 1 in 10,000 per year. It has been concluded that currently the results of these studies, taken individually or collectively reviewed by expert groups, are insufficient either to make a conclusive judgement on validity or to quantify appropriate exposure restrictions (our emphasis) ... However, having a statistical association does not imply that exposure causes childhood leukaemia, and the possibility that confounding or some bias in the data may provide an explanation cannot be yet ruled out."
All "yellow box" quotes from HPA advice to Abingdon Council, December 2007, unless otherwise stated
This is simply untrue. The validity that there is an increase in risk from exposure to ELF EMFs is no longer under much dispute. The SAGE stakeholder group concluded that the evidence was very strong for the association between childhood leukaemia and ELF EMFs ("This working assumption, for the purposes of assessing options, is that for all time-average fields greater than 0.4 µT the risk is doubled"), particularly residential proximity to high voltage overhead transmission lines (HVOTLs).
On the basis of appropriate exposure restrictions, it was deemed that a doubling of childhood leukaemia risk would not contribute enough new cases of leukaemia to warrant any action on existing properties, as the cost of such action would outweigh the 'value of lives lost' through inaction. However, SAGE did make official recommendations that minimising exposure is desirable: "We have adopted a principle of seeking ways to make people's exposure to electric and magnetic fields as low as reasonably achievable." (Page 24, Section 2.1 - Decisions about the Science)
Worse than their downplaying of the childhood leukaemia evidence is the near complete dismissal of evidence that below-ICNIRP ELF EMF effects exist:
"There is little evidence for any raised risks of other cancer type in children or for any type of cancer in adults. In addition, laboratory studies have not provided any consistent evidence that magnetic fields are genotoxic or have a carcinogenic effect ... In addition, laboratory studies have not produced any good evidence of field-related effects with exposures below about 100 µT" (our emphasis)
The words consistent and good here are typical of the old "NRPB-speak" reports where entirely subjective words are used to "hide" existing evidence under the caveat of not being of substantial quality or quantity. There is no reference to exactly what would be "consistent" evidence, nor "good" evidence, but to give the impression that there is not really anything of importance in the literature is grossly misleading.
Other health effects have been investigated in relation to proximity to powerlines and exposure to power frequency magnetic fields of a similar level. The findings showed a number of studies finding serious and significant effects for adult skin cancer[1], breast cancer[2], Lou Gehrig's disease (ALS - Amyotrophic Lateral Sclerosis) [3][4][5] and miscarriage[6][7][8].
The California Department of Health looked at the literature in 2002 and concluded that "EMFs were responsible for an increase in childhood leukemia, adult brain cancer, Lou Gehrig's disease, and miscarriage". They also concluded that "they did not find there was a strong enough association between EMFs and birth defects and low birth weight, and were divided on the evidence for suicide and adult leukemia" [9]. This disagrees with the 2001 IARC review (referenced in the HPA letter) that classified EMFs as only "possible carcinogens", giving the following reason:
"there were reasons why animal and test tube experiments might have failed to pick up a mechanism or a health problem; hence, the absence of much support from such animal and test tube studies did not reduce their confidence much or lead them to strongly distrust epidemiological evidence from statistical studies in human populations. They therefore had more faith in the quality of the epidemiological studies in human populations and hence gave more credence to them."
Professors Mike O'Carroll (University of Sunderland, UK) and Denis Henshaw (University of Bristol, UK) have jointly authored a paper looking at pooled statistics for papers that have investigated the relationship between ELF EMFs and a number of diseases (including childhood and adult leukaemia), with some revealing findings:
Disease |
Studies |
Positives |
Significant positives |
Significant negatives |
childhood leukaemia |
19 |
16 |
3 |
0 |
adult leukaemia |
43 |
32 |
11 |
0 |
9 other diseases |
150 |
110 |
36 |
1 |
Total |
212 |
158 |
50 |
1 |
|
p-Value for total |
2.5 x 10-13 |
4.4 x 10-15 |
|
Notes:
1. The column headed 'Studies' refers to the number of epidemiological studies considered in each category.
2. The column headed 'Positives' represents the number of positive odds ratios found in each category, taking one representative odds ratio per study as assessed by the California panel.
3. The column headed 'Significant positives' represents the number of positive odds ratios which were statistically significant in their own right at the 95% confidence level.
4. The 'p-values for total' represent the probability that the total number of Positives and the total number of Significant positives was a chance finding.
In layman's terms, unless there are solid reasons that these p-values and significant findings are in error (i.e. consistently unrecognised or uncontrolled confounding factors), the evidence presented here gives an extremely strong argument that the association is not only convincing, but sufficiently so to be deemed causal.
In the report itself they provided objectively calculated levels of confidence in possible risks and the implications that these may have. The findings are quite alarming, giving scientific credibility to the likelihood that the impact of the other diseases could conceivably be up to 100 times greater than that of childhood leukaemia alone!
"We do not think it is rational to base an assessment on childhood leukaemia alone, when most of the hypothesised mechanisms and their supporting evidence relates to biological systems involved in many diseases, rather than exclusively to childhood leukaemia. The decreasing Degree of Certainty with greater numbers of diseases is however reflected in the credibility factors. Therefore, while there remains considerable uncertainty and imprecision in such assessments, it seems sensible to give consideration to the above scenarios and multiple outcomes, without adopting any one as definitive."
Adverse health effects associated with exposure to ELF electric and magnetic fields - assembly of scientific evidence and discussion of possible public health impact
O'Carroll MJ, Henshaw DL
It is very true that there is little research finding direct cellular effects from extremely low frequency magnetic fields below 0.1 mT, but there is evidence to support these lower levels affecting the action[10][11][12][13] and production[14][15][16] of tamoxifen and particularly melatonin, which in turn are understood to be radioprotective (and therefore likely to have a protective effect against cancer)[17][18][19]. This gives not only mechanistic support for the association, but also provides indirect evidence of laboratory support.
A number of these have been very well summarised by Professor Henshaw and Professor Russell Reiter of the University of Texas in their 2005 paper on melatonin and magnetic fields[20].
However, this evidence is also dismissed in the letter, including an ad-hominem attack on Professor Henshaw:
"The report (AGNIR 2006) concludes that overall the evidence does not support the hypothesis that exposure to magnetic fields was associated with an increased risk of breast cancer Plus it was concluded that magnetic fields did not appear to affect the production or biological action of melatonin. Professor Henshaw, a physicist from the University of Bristol, has disagreed with these conclusions, although he does not have expertise either in breast cancer or melatonin physiology."
This personal criticism is completely unjustifiable, as the paper highlighting this "disagreement"[20] has been published in a peer-reviewed journal, and has therefore passed the judgement of being worthy science*. The other author on the paper happens is Professor Russell Reiter, who has been one of the leading researchers on melatonin for over 20 years. The other papers we have cited in this section have indeed involved prominent biologists with good understandings of melatonin physiology.
* It is also worth remembering that, in contrast, the AGNIR report itself did not have to pass any form of peer reviewal.
Strangely, having pushed the "lack of scientific evidence" argument, the HPA letter then summarises that the conclusions of the survey "are consistent with the current scientific understanding of electromagnetic fields on health and current UK EMF exposure guidelines".
The evidence for guaranteed causation from extremely low frequency electromagnetic fields is not conclusive, but the Health Protection Agency exists to protect the public, where possible, from unnecessary risk. There is clearly enough evidence to warrant a precautionary approach, and laying into independent precautionary recommendations such as these undermines the public trust in the organisation.
Links:
- View HPA Letter in full (427 KB)
- First SAGE interim report (2.3 MB)
- 2006 AGNIR Report (1.4 MB)
References:
[1] - Tynes, Tore; L Klaeboe, T Haldorsen (May 2003). "Residential and occupational exposure to 50 Hz magnetic fields and malignant melanoma: a population based study". Occup Environ Med 60 (5): 343-7. [View Abstract]
[2] - Hansen, J (January 2001). "Increased breast cancer risk among women who work predominantly at night". Epidemiology 12 (1): 74-7. [View Abstract]
[3] - Feychting, Maria; Anders Ahlbom, F Jonsson, NL Pederson (July 2003). "Occupational magnetic field exposure and neurodegenerative disease". Epidemiology 14 (4): 413-9 [View Abstract]
[4] - Hakansson, Niklas; P Gustavsson, Birgitte Floderus, Christof Johanen (July 2003). "Neurodegenerative diseases in welders and other workers exposed to high levels of magnetic fields". Epidemiology 14 (4): 420-6. [View Abstract]
[5] - Ahlbom, Anders (2001). "Neurodegenerative diseases, suicide and depressive symptoms in relation to EMF.". Bioelectromagnetics (Suppl 5): S132-43. [View Abstract]
[6] - Lee, GM; Michael Yost, RR Neutra, L Hristova, RA Hiatt (January 2002). "A nested case-control study of residential and personal magnetic field measures and miscarriages". Epidemiology 13 (1): 21-31. [View Abstract]
[7] - Li, De-Kun; Roxana Odouli, S Wi, T Janevic, I Golditch, TD Bracken, R Senior, R Rankin, R Iriye (January 2002). "A population-based prospective cohort study of personal exposure to magnetic fields during pregnancy and the risk of miscarriage". Epidemiology 13 (1): 9-20. [View Abstract]
[8] - Cao, YN; Y Zhang, Y Liu (August 2006). "Effects of exposure to extremely low frequency electromagnetic fields on reproduction of female mice and development of offsprings". Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 24 (8): 468-70. [View Abstract]
[9] - "An Evaluation of the Possible Risks From Electric and Magnetic Fields (EMFs) From Power Lines, Internal Wiring, Electrical Occupations and Appliances", California EMF Program [View Report]
[10] - Liburdy RP, Callahan DE, Harland J, Dunham E, Sloma TR, Yaswen P (November 1993) "Experimental evidence for 60 Hz magnetic fields operating through the signal transduction cascade. Effects on calcium influx and c-MYC mRNA induction". FEBS Lett. 1993 Nov 22;334(3):301-8. [View Abstract]
[11] - Harland J, Engström S, Liburdy R (1999) "Evidence for a slow time-scale of interaction for magnetic fields inhibiting tamoxifen's antiproliferative action in human breast cancer cells". Cell Biochem Biophys. 1999;31(3):295-306. [View Abstract]
[12] - Blackman CF, Benane SG, House DE (February 2001) "The influence of 1.2 µT, 60 Hz magnetic fields on melatonin- and tamoxifen-induced inhibition of MCF-7 cell growth", Bioelectromagnetics. 2001 Feb;22(2):122-8 [View Abstract]
[13] - Ishido M, Nitta H, Kabuto M (July 2001) "Magnetic fields (MF) of 50 Hz at 1.2 µT as well as 100 µT cause uncoupling of inhibitory pathways of adenylyl cyclase mediated by melatonin 1a receptor in MF-sensitive MCF-7 cells". Carcinogenesis. 2001 Jul;22(7):1043-8 [View Abstract]
[14] - Kato M, Honma K, Shigemitsu T, Shiga Y (1993) "Effects of exposure to a circularly polarized 50-Hz magnetic field on plasma and pineal melatonin levels in rats". Bioelectromagnetics. 1993;14(2):97-106 [View Abstract]
[15] - Kato M, Honma K, Shigemitsu T, Shiga Y (January 1994) "Circularly polarized 50-Hz magnetic field exposure reduces pineal gland and blood melatonin concentrations of Long-Evans rats", Neurosci Lett. 1994 Jan 17;166(1):59-62 [View Abstract]
[16] - Davis S, Mirick DK, Chen C, Stanczyk FZ (August 2006) "Effects of 60-Hz magnetic field exposure on nocturnal 6-sulfatoxymelatonin, estrogens, luteinizing hormone, and follicle-stimulating hormone in healthy reproductive-age women: results of a crossover trial", Ann Epidemiol. 2006 Aug;16(8):622-31 [View Abstract]
[17] - Vijayalaxmi, Reiter RJ, Herman TS, Meltz ML (December 1996) "Melatonin and radioprotection from genetic damage: in vivo/in vitro studies with human volunteers", Mutat Res. 1996 Dec 20;371(3-4):221-8 [View Abstract]
[18] - Vijayalaxmi , Meltz ML, Reiter RJ, Herman TS, Kumar KS (March 1999) "Melatonin and protection from whole-body irradiation: survival studies in mice", Mutat Res. 1999 Mar 10;425(1):21-7 [View Abstract]
[19] - Blask DE, Brainard GC, Dauchy RT, Hanifin JP, Davidson LK, Krause JA, Sauer LA, Rivera-Bermudez MA, Dubocovich ML, Jasser SA, Lynch DT, Rollag MD, Zalatan F (December 2005) "Melatonin-depleted blood from premenopausal women exposed to light at night stimulates growth of human breast cancer xenografts in nude rats", Cancer Res. 2005 Dec 1;65(23):11174-84 [View Abstract]
[20] - Henshaw DL, Reiter RJ (2005) "Do magnetic fields cause increased risk of childhood leukemia via melatonin disruption?", Bioelectromagnetics. 2005;Suppl 7:S86-97 [View Abstract]
Also in the news
CHILDREN with LEUKAEMIA working in Westminster
London based charity CHILDREN with LEUKAEMIA are also working tirelessly to raise awareness of the increased risk of childhood leukaemia from exposure to electromagnetic fields:
Two MPs have put the spotlight on new Government legislation which could increase the number of children at risk of leukaemia - a risk associated with living close to high voltage power lines.
Nick Hurd, Conservative MP for Ruislip Northwood, has introduced an amendment at the committee stage of the Housing and Regeneration Bill. The amendment imposes a duty on the new Homes and Communities Agency to consider the risks to health arising from the Electric and Magnetic Fields (EMFs) from power lines.
Richard Benyon, MP for Newbury, also introduced an amendment to the Government's new Planning Bill. The purpose of this Bill is to create a new Planning Commission. This commission would help fastrack major infrastructure projects by replacing Public Inquiries on controversial projects such as power stations and railway lines and setting National Policy Statements on subjects such as power lines.
RICS Overview document on SAGE recommendations
Michael Jayne, a lecturer at Nottingham Trent University (and a member of both RICS and SAGE), has written an excellent article for RICS on the SAGE recommendations and implications in the light of current science, entitled "Danger Fields". Some extracts from the document are as follows:
"A the time of writing, the main proven health problem is a statistical association between a doubling in the incidence of childhood leukaemia and fields of 0.4 microteslas (unit of measurement for magnetic fields) and above, though no causal link has been established..."
"The report (SAGE first interim assessment, April 2007) identified two key precautionary measures that should be taken by the government:
- more information should be provided to the public about exposures and actions they could take themselves to reduce exposure
- electricity companies should be encouraged to choose the optimal phasing (usually transposed phasing) for all new 132 kV lines, and to convert the 12% of existing 132 kV lines that are not transposed but could easily be converted."
"The best option for obtaining significant reduction in exposures, SAGE concluded, was the physical separation of buildings and power lines via a strategy they call 'corridors for new build': stopping the building of new homes, schools, other childcare facilities, hotels and holiday accommodation close to existing lines, and preventing the erection of new lines close to these categories of buildings."
The document covered a lot of SAGE's work and recommendations in an objective and brief manner, and is well worth a read.
- View article in full (551 KB)
Misleading summary from mobile phone study meta-analysis
Researchers from the University of Utah have published a paper this month looking at the current epidemiological research into mobile phones and brain tumours, and summarised that "We found no overall increased risk of brain tumors among cellular phone users. The potential elevated risk of brain tumors after long-term cellular phone use awaits confirmation by future studies.".
What they didn't point out so clearly is that they found a statistically significant protective effect from using cellular phones overall (OR = 0.90, 95% CI 0.81-0.99) in their meta-analysis, and despite this a statistically signifiant increase in risk from long term users only (OR = 1.25, 95% CI 1.01-1.54). This is remarkable that it implies that, even including the long term users, the data as a whole is supportive of the idea that short term cellular phone usage has a protective effect!
As many of the epidemiological studies included in this analysis are from the INTERPHONE project, it lends a lot of support to the very convincing argument by Lloyd Morgan that the protective effect is caused by a number of serious methodology flaws in the INTERPHONE work causing the risk to be underestimated across the entire dataset. If so, and the protective effect is an artefect (which seems to make sense), then the statistically significant increase would become even more marked - and this at a point where it would be unlikely to see any increase in brain tumours even if one did exist (as the typical latency period is 15 - 25 years, according to the evidences from other causes of brain cancer in humans).
Kan P, Simonsen SE, Lyon JL, Kestle JR (January 2008) "Cellular phone use and brain tumor: a meta-analysis", J Neurooncol. 2008 Jan;86(1):71-8 [View Abstract]
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