This news is my response to Anne McIntosh MP over three Ministerial replies she has received relating to health and global warming questions about powerlines.
Thank you for your letter 8 Nov and Helen Liddell's reply to PQ No. 1999/3365, and sorry for delay in response. The Minister's letter contains an important error, which is repeated in her letter to you of 5 December in response to correspondence from Ian Cunniffe. I also deal below with John Prescott's letter of 21 Nov.
The issue is health effects of power lines. I was giving evidence on this in Ireland earlier this month. The most important and most summative study is the recent multinational pooled study by Ahlbom et al (Brit J Cancer 83 692-698 2000) which confirms an association between residential exposure to magnetic fields above 0.4 microTesla and childhood leukaemia. Remember an association is a statistical concurrence between exposure and incidence; it is not itself proof of a cause.
The association is confirmed at higher field levels, consistent with living close to powerlines, though its absence is confirmed at lower levels.
In her reply to 1999/3365 Helen Liddell refers to the UKCCS study, which is just one of those covered in the multinational study above. The UK stidy lacked data (especially controls) at higher levels so was inconclusive where it matters. Helen Liddell's reply says that NRPB advice is that "while the possibility of an association cannot be dismissed, there is insufficient evidence of any adverse health effect from the fields from power supplies to which the general public may be exposed".
While the reply appears to be carefully crafted to mislead, by referring to the general public whereas it is nearby residents who are in question, the reply is also in error in putting "associaton" as only a possibility, when research has confirmed it. It is the cause (and effect) which is a possibility, as expressly stated in earlier NRPB statements.
A correct statement would be "Multinational research has confirmed an association between power supply magnetic fields and childhood leukaemia, but this does not establish a causal link, and so few children are exposed at these levels in the UK that the associated incidence is extremely rare. However this does not address exposure to electric fields or contaminant particles, nor illnesses other than cancer."
There must be some reservations about advice from NRPB. We should learn from the BSE affair that government advisers have at best a qualified independence and are not always reliable. NRPB has reacted erroneously before, in dismissing Professor Henshaw's physics of aerosol particles hastily, zealously and erroneously in 1996. This was at the level of a schoolboy howler as I show in the Appendix below.
Helen Liddell's letter of 5 December dabbles at length in both Professor Henshaw's work and Dr Preece's work, while claiming that, as Dr Preece's work has not been published, it is difficult to comment. It is therefore unsound to try to cherry pick points on Dr Preece's work to suit her denial, especially when based on speculations that, for example, the confounder of smoking has not been taken into account. Why is Helen Liddell speculating so partially? She must be poorly advised politically as well as scientifically. Again she says misleadingly "the possibility of an association cannot be dismissed"; this is called "spin", I believe.
I would be grateful if you would put these points to Helen Liddell and ask if she would review her response.
Finally, John Prescott's letter of 21 Nov. He is advised that there is no effect of powerlines on global warming. His advisers might have been thinking only of the thermal effect of heat loss from powerlines, which would be insignificant for global warming. However, the real effect comes from profligate use of energy and consequent production of greenhouse gases. Strictly we should say that this is a greenhouse gas effect rather than global warming, since the cause of global warming is not certain (eg sunspot activity) but it is widely considered likely that greenhouse gas pollution is a significant factor.
The profligate waste of energy comes from encouraging large power stations (where upwards of half the primary energy is dumped as waste heat) in the far north, remote from net demand in the far south, and from losses in bulk long-distance transmission. Most of the waste would be avoidable by using distributed smaller scale CHP (in accordance with government policy) and very soon using gas powered fuel cell microgenerator systems (see New Scientist 18 Nov and 25 Nov). These local generation solutions would reduce the need for excessive grid.
As an indication of the scale of this energy, the proposed Yorkshire grid line would promote the extra excess generation in the far north of some 2GW, with the consequent avoidable waste of energy worth over 500 million pounds per annum at wholesale prices. Objectors have saved the national economy over 3 billion pounds so far by delaying the project. Mr Prescott, please note.
John Prescott also ventures a dabble into the physics of atmospheric particles. His conclusion that there is nothing to worry about would be fair on the basis of the blinkered view of his advisers, restricted as they apparently are to consideration of direct atmospheric heating effects of powerlines, but they completely miss the point.
Why are Ministers and their advisers so eager to dismiss concerns, rather than to take them seriously? Shades of BSE denials? Is there an institutionalised prejudice in the Civil Service and career scientific advisers predisposing them towards dismissal? It seems to transcend even party politics.
I would be grateful if you would put all the above points to both Ministers, in the hope of being taken seriously and perhaps getting competent scientific advice.
With many thanks for your continued efforts,
-- Mike O'Carroll