Sir, – The statement by two eminent haematologists (Letters, November 23rd) is very welcome in view of the recent upsurge in misinformation regarding a perceived link between leukaemia and low energy electromagnetic fields.
More than 30 years of international research has failed to produce any definite evidence of a connection between power lines and cancer. The absence of any detrimental effect is consistent with the fact that there is no physical basis for such a link. This conclusion is based on well-established scientific principles associated with quantum physics, which show that the energy associated with typical power lines in Ireland is many millions of times less than that required to break the weakest molecular bond.
The sight of pylons in our beautiful countryside and the cost of putting them underground are a completely different matter. – Yours, etc,
DENIS O’SULLIVAN,
Professor Emeritus,
Shanganagh Vale,
Dublin 18.
Sir, – I totally agree with Professors McCann and Smith (November 24th) that it is indeed a spurious health claim that low-energy electromagnetic fields from electricity pylons have been proven to cause childhood leukaemia. However, in 2002 the International Agency for Research on Cancer (IARC) classified low-energy electromagnetic fields as a possible or 2B carcinogen.
This classification was based on a review of epidemiological literature on electromagnetic fields and health by Prof Anders Ahlbom (Karolinska Institute, Sweden). Ahlbom et al (2001) concluded: “Among all the outcomes evaluated in epidemiological studies on EMF, childhood leukaemia in relation to post natal exposures above 0.4 micro tesla is the one for which there is the most evidence of an association. The relative risk has been estimated at 2.0 (double the risk) in a large pooled analysis. This is unlikely to be due to chance, but may be, in part, due to bias”.
The entire area was reviewed in by the EU Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR), where they concluded: “The previous conclusion that ELF magnetic fields are a possible carcinogen, chiefly based on childhood leukaemia results, is still valid.”
In my opinion, while it is unproven that low-energy electromagnetic fields actually cause cancer, it cannot be denied that it is right and proper they should form part of an informed debate with regard to the pylon controversy. – Yours, etc,
NIGEL HILLIS MIEI,
Ballybay,
Co Monaghan.
Sir, – Profs McCann and Smith (November 23rd) state that evidence is lacking for a causal relationship between low energy electromagnetic fields and leukaemia, and advise that “spurious health claims” should not confuse a “constructive debate” in the current controversy about health hazards and human exposure to electricity pylons.
Every honest scientist will acknowledge that absence of evidence does not mean evidence of absence, and factors not yet identified may account for the large body of observational evidence suggesting a link between exposure to EMF and risks to optimal health.
Researchers at Shanghai University have recently discovered that children with a faulty variant of a protective gene were 4.3 times more likely to develop leukaemia if they lived within 330 feet of a power line. Their observation of an indirect effect on human DNA through EMF exposure cannot be discounted as “spurious”. The EPA , while mindful of the conflicting evidence, acknowledges there is reason for concern, and advises “prudent avoidance” of unnecessary exposure to EMF.
In their Bioinitiative Report, leading researchers in the field of EMF exposure warned, "The existing standards of public safety are completely inadequate to protect health". This is not a "spurious health claim. It is a serious warning for EirGrid to take note of. – Yours, etc,
Dr NEVILLE WILSON,
Medical Director,
The Leinster Clinic,
Maynooth,
Co Kildare.