22/06/2005 - Childhood Cancer and Power lines
This is a response to the paper, and rapid-response letters, recently published
in the British Medical Journal, "Childhood cancer in relation to distance
from high voltage power lines in England and Wales: a case-control study",
by Gerald Draper, Tim Vincent, Mary E Kroll and John Swanson .
Their paper showed an approximate doubling in childhood leukaemia between 50
to 100 metres from National Grid's 275 kV and 400 kV high-voltage electricity
transmission line network, with a rise again from about 250 metres to well over
600 metres. There was also a slight rise in brain tumours after 250 metres.
Despite the statements of some scientists closely connected with the
Leukaemia Research Fund (LRF) who seem determined to dismiss the EMF link with
childhood leukaemia, the UK Childhood Cancer Study (UKCCS)  did find elevated
incidence of childhood leukaemia close to powerlines. When the UKCCS data is
plotted as simple Odds Ratios for 275 kV and 400 kV powerlines , it shows a
similar peak as this latest study at 100 metres and, more importantly, rising
again after 150 metres.
This new study supports a likely magnetic field effect on child leukaemia
incidence near to powerlines. 100 metres is beyond the typical 400 nanotesla
point, but this is without taking polarisation / ellipticity of the field into
account which induces higher currents in people and will be likely to increase
the effective distance .
After a dip, both studes then show an ongoing rise in incidence after a few
hundred metres which would closely fit the Henshaw charged aerosol hypothesis.
Actual measurements  have found charged aerosol effects at ground level from
about 150 metres to several km from powerlines - a long way from the source of
the corona ions and affecting a significant number of people.
If Denis Henshaw and his team are right, then the adverse health effects of
powerlines will extend to well over 1 km from the powerlines. It would be easy
to test for this by extending the analysis of the Draper data up to a distance
of at least 2km to see how far the elevated risk continues.
- Alasdair Philips
 UKCCS Investigators, Childhood cancer and residential proximity to power
lines, 2000, Br.J.Cancer, 83(11), 1573-1580
 Graph available at:
 Ainsbury, E, et al, Conference poster,
 Fews A.P., et al, Modification of atmospheric DC fields by space charge from
high voltage power lines, 2002, Atmospheric Research, 63: 271 - 289