Both Draper and UKCCS data support Henshaw hypothesis
Despite the statements of some scientists, the 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 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.
 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
Powerwatch comments on potential health effects of electromagnetic fields
Competing interests: No competing interests