Friday June 03rd 2005, 8:17 pm
Filed under: Power line news, Epidemiology, 50/60 Hz
The long awaited UK Draper study has finally been published in the British Medical Journal, confirming, yet again, the connection between environmental level powerline magnetic fields and childhood leukaemia.
How much more evidence do we need to protect public health?
With the current public concerns being expressed in New Zealand and Canada (previous message) over powerlines and health, how will ICNIRP’s BPIEs explain this one away?
I wonder how the current ARPANSA powerline standards working committee will deal with it. As I mentioned previously ARPANSA fully intends to accept as a “health based standard” ICNIRP’s 1000 mG exposure level.
Stay Tuned for more on this one….
Don
As reported in the Sydney Morning Herald:
Power lines and leukemia: study highlights risk to babies
By Julie Robotham, Medical Editor
June 3, 2005 - 10:29AM
Babies who live near high-voltage power lines are almost twice as likely as others to develop leukemia during childhood, according to the largest study ever to be conducted into the long-standing question.
But despite detailed analysis of more then 9000 childhood cases of leukemia over three decades, the Oxford University scientists who led the research say there is still insufficient evidence to establish with any certainty whether the magnetic fields around the cables actually cause some cases of the cancer.
Gerald Draper, Honorary Senior Research Fellow at the university’s Childhood Cancer Research Group, identified the birth records of children born between 1962 and 1995 who later developed cancer, and mapped the addresses listed on the children’s birth certificates against the national electricity grid in England and Wales.
The same was done for a control group of children who did not have cancer - each matched to one of the cancer patients for date of birth, sex and birth registration district.
Draper found the 9700 children with leukemia - the most common childhood cancer - were 70 per cent more likely than the others to have lived within 200 metres of a high voltage powerline. The link grew weaker the further away from power lines children lived.
Among the 20,000 children who developed cancers other than leukemia, there was no extra likelihood of having lived near overhead cables.
Despite the findings, Dr Draper was reluctant to suggest power lines might cause leukemia.
Magnetic fields from power lines were “the most obvious explanation”. But at a distance of 200 metres, these forces were typically lower than other sources of magnetism within the home, such as household electrical wiring and applicances, he said.
“We have no satisfactory explanation for our results in terms of causation, and the findings are not supported by convincing laboratory data or any accepted biological mechanism,” Dr Draper wrote in the British Medical Journal.
Brad Page, chief of the Energy Supply Association of Australia, said Australia uses the same 400, 275 and 132 kilovolt transmission cables considered in the UK research, but it was unclear whether similar proportions of Australian children lived near them.
“People should not place themselves in unreasonable proximity to these things,” Mr Page said.
More information:
http://bmj.bmjjournals.com
From the British Medical Journal:
http://bmj.bmjjournals.com/cgi/content/full/330/7503/1290?ehom#TBL1
Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study
Gerald Draper, honorary senior research fellow1, Tim Vincent, research officer1, Mary E Kroll, statistician1, John Swanson, scientific adviser2
1 Childhood Cancer Research Group, University of Oxford, Oxford OX2 6HJ, 2 National Grid Transco plc, London WC2N 5EH
BMJ 2005;330:1290 (4 June), doi:10.1136/bmj.330.7503.1290
Correspondence to: G J Draper gerald.draper@ccrg.ox.ac.uk
Abstract
Objective To determine whether there is an association between distance of home address at birth from high voltage power lines and the incidence of leukaemia and other cancers in children in England and Wales.
Design Case-control study.
Setting Cancer registry and National Grid records.
Subjects Records of 29 081 children with cancer, including 9700 with leukaemia. Children were aged 0-14 years and born in England and Wales, 1962-95. Controls were individually matched for sex, approximate date of birth, and birth registration district. No active participation was required.
Main outcome measures Distance from home address at birth to the nearest high voltage overhead power line in existence at the time.
Results Compared with those who lived > 600 m from a line at birth, children who lived within 200 m had a relative risk of leukaemia of 1.69 (95% confidence interval 1.13 to 2.53); those born between 200 and 600 m had a relative risk of 1.23 (1.02 to 1.49). There was a significant (P < 0.01) trend in risk in relation to the reciprocal of distance from the line. No excess risk in relation to proximity to lines was found for other childhood cancers.
Conclusions There is an association between childhood leukaemia and proximity of home address at birth to high voltage power lines, and the apparent risk extends to a greater distance than would have been expected from previous studies. About 4% of children in England and Wales live within 600 m of high voltage lines at birth. If the association is causal, about 1% of childhood leukaemia in England and Wales would be attributable to these lines, though this estimate has considerable statistical uncertainty. There is no accepted biological mechanism to explain the epidemiological results; indeed, the relation may be due to chance or confounding.
Download the full paper at:
http://bmj.bmjjournals.com/cgi/content/full/330/7503/1290?ehom#TBL1
Source:
http://www.emfacts.com/weblog/index.php?p=69