A higher risk of childhood leukemia, particularly of
acute lymphoblastic leukemia (ALL), was linked to high magnetic field
According to recent research published in the
International Journal of Cancer, "Residential power-frequency MFs were
labeled as a possible human carcinogen by the International Agency for
Research on Cancer panel. In response to great public concern, the
World Health Organization urged that further epidemiologic studies be
conducted in high-exposure areas such as Japan."
"We conducted a population-based case-control study, which covered
areas inhabited by 54% of Japanese children," explained M. Kabuto and
colleagues, National Institute for Environmental Studies. "We analyzed
312 case children (0-15 years old) newly diagnosed with ALL or acute
myelocytic leukemia (AML) in 1999-2001 (2.3 years) and 603 controls
matched for gender, age and residential area. Weekly mean MF level was
determined for the child's bedroom. MF measurements in each set of a
case and controls were carried out as closely in time as possible to
control for seasonal variation.
"We evaluated the association using conditional logistic regression
models. The odds ratios for children whose bedrooms had MF levels of
0.4 mc T or higher compared with the reference category (MF levels
below 0.1 mc T) was 2.6 (95% CI=0.76-8.6) for AML + ALL and 4.7
(1.15-19.0) for ALL only. Controlling for some possible confounding
factors did not alter the results appreciably. Even an analysis in
which selection bias was maximized did not fully explain the
association. Most of the leukemia cases in the highest exposure
category had MF levels far above 0.4 mc T."
The researchers concluded, "Our results provided additional evidence
that high MF exposure was associated with a higher risk of childhood
leukemia, particularly of ALL."
Kabuto and colleagues published their study in International Journal of
Cancer (Childhood leukemia and magnetic fields in Japan: A case-control
study of childhood leukemia and residential power-frequency magnetic
fields in Japan. Int J Cancer, 2006;119(3):643-650).
For additional information, contact M. Kabuto, National Institute for
Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 3058506, Japan.
This article was prepared by Clinical Oncology Week editors from staff
and other reports. Copyright 2006, Clinical Oncology Week via
[FROM ROCKY MOUNTAIN BLOOD AND BONE
MARROW TRANSPLANT PROGRAM....may be
repeating distribution of this Japanese study but felt distribution of
this particular post on the Rocky Mountain Blood and Bone Marrow
Transplant Program is particularly noteworthy.....jcm notes 10-15-06]
[ADDITIONAL COMMENT BY JOANNE C.
10-15-06 .....need to examine entire article re what is meant by
magnetic field in bedrooms. IF, measurements are taken with focus
entirely on the magnetic field iteself, and IF those measurements are
"ambient readings," or even if not, such ambient magnetic field
measurements do not in any way address the issue of a child or person
sleeping in a bed with metal mattress springs who is sleeping close to
electrical items such as an electric meter, an electric clock radio,
lamps with dimmer switches or high intensity lamps, small fans on
nightstands and headboards, power supply boxes for cordless phones or
electronic games, wiring errors, waterpipes with high magnetic fields,
high frequencies on electrical siring and much more. It is
highly doubtful that the aspect of the EMR spectrum that is causing the
harm is the magnetic field itself.
An electric clock has a magnetic field of or
close to 200.0 milligauss. Magnetic field readings can be as low
as 2.0 milligauss or lower "on-the-pillow" and yet significant
improvement in health can be attained by simply moving the electric
clock or clock radio across the room.
These additional issues are very important
and may explain "confounding factors" but even so, the above study
provides evidence of the urgent need to inform the public re
lowering magnetic field exposures in bedrooms. ]