effect of EMFs on cardiovascular system
In 1998 Braune
and colleagues created a stir by reporting that exposure to an electromagnetic
field (EMF) generated by a mobile phone was associated with an increase
in blood pressure. This group has now repeated the experiment but
with one crucial difference - the subjects were exposed to the EMF
or sham-exposed in a random manner, whereas in the first study the
subjects were all sham-exposed first. In the new study the blood
pressure again increased by about 5 mm Hg in the course of an experiment
but this was independent of the EMF exposure. In other words, the
EMF was not associated with any change in the cardiovascular measures
that were assessed during the experiment.
This study illustrates
the importance of randomization of exposure. It also demonstrates
the necessity for studies to be replicated. A key factor in assessing
whether a causal relationship exists between an exposure and an
outcome is the consistency of the finding of an association in different
For more on
this, see "Research - Clinical
Experiments - cardiovascular effects".
Braune S, Riedel A, Schulte-Monting J, Raczek J (2002). Influence
of a radiofrequency electromagnetic field on cardiovascular and
hormonal parameters of the autonomic nervous system in healthy individuals.
Radiation Research 158:352-356.
review of epidemiological studies of cellular phones
Radiation Protection Authority, SSI, has published a review of epidemiological
studies of cellular telephones and cancer risk. SSI commissioned
Drs. Boice and McLaughlin from the International Epidemiology Institute
in Maryland, USA, to carry out the review. The authors state: "A
in the United States and Sweden are non-informative,
either because the follow-up was too short and numbers of cancer
too small (USA) or because of serious methodological limitations
(Sweden). In contrast, five well-designed epidemiologic studies
have been conducted in three countries by investigators using different
In our view, a consistent picture has emerged from
these studies that appears to rule out, with a reasonable degree
of certainty, a causal association between cellular telephones and
cancer to date".
The review can
be read at www.ssi.se/ssi_rapporter/pdf/ssi_rapp_2002_16.pdf
Boice JD, McLaughlin JK. Epidemiologic studies of cellular telephones
and cancer risk - a review. Swedish Radiation Protection Authority,
research centre to be established in Australia
A new US $1.3
million research centre is to be established in Australia to study
the possible health effects of electromagnetic energy emissions
from mobile phones and mobile phone towers. The National Health
and Medical research Council will support an actual or "virtual"
Centre of Research Excellence in Radiofrequency Electromagnetic
Energy over the next five years.