Intended for healthcare professionals


Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study

BMJ 2005; 330 doi: (Published 02 June 2005) Cite this as: BMJ 2005;330:1290

Both Draper and UKCCS data support Henshaw hypothesis

Despite the statements of some scientists, the UKCCS [1] 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 [2], it shows
a similar peak as this latest study at 100 metres and, more importantly, rising
again after 150 metres.

Comparison of Draper and UKCCS child cancer data

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 [3].

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 [4] have found charged aerosol effects from about 150 metres
to several km from powerlines before diffusing to ground level - a long way from
the source of the corona ions and affecting a significant number of people.

If Henshaw is 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.


[1] UKCCS Investigators, Childhood cancer and residential proximity to power lines, 2000,
Br.J.Cancer, 83(11), 1573-1580

[2] Graph available at:

[3] Ainsbury, E, et al, Conference poster,

[4] Fews A.P., et al, Modification of atmospheric DC fields by space charge from
high voltage power lines, 2002, Atmospheric Research, 63: 271 - 289

Competing interests:
Powerwatch comments on potential health effects of electromagnetic fields

Competing interests: No competing interests

16 June 2005
Alasdair M Philips
Director of Powerwatch