No genotoxic effects from RF fields in human blood cells .
Health Canada have failed to find evidence of genotoxicity
in human blood cells exposed for 24 hours to either pulsed or continuous
wave RF radiation from a 1.9 GHz field. The authors comment that of
the four studies assessing the effect of a 24-hour RF-field exposure
on human blood cells, only one has shown an increase in micronucleated
cells (a sign of chromosome damage). They suggest that the positive
study may have been due to increased temperatures in the cell cultures.
For more on these
studies, see "Research - Toxicological
Experiments - cancer studies".
In the April 2000 issue of Which? Magazine, the UK Consumers' Association published a report on hands-free accessories for mobile phones. They reported that tests showed that the use of these accessories increases the deposition of radiofrequency (RF) energy in the head by up to three times compared to a mobile phone alone held close to the head.
Now a group from
the Motorola Florida Research Laboratories reports the opposite - the
hands-free accessories decrease the RF energy exposure in the head.
They state that the UK tests "were not performed with internationally
recommended methodologies for SAR measurements aimed at determining
compliance with RF-radiation exposure limits". The authors point
out two main deficiencies in the methodology used in the UK study. The
first was the use of a model without the equivalent of the human torso.
If at least some of the wire runs close to the torso, the RF exposure
is significantly lower in the head because the human body attenuates
the electromagnetic field along the wire. The second was the positioning
of the phone 13 mm from the ear, which introduced an artificial reduction
in SAR, compared to the device operating next to the ear.
Reports on the health effects of RF radiation have appeared frequently from various countries in the last few years. In addition to the reports from the Royal Society of Canada and the Independent Expert Group on Mobile Phones from the UK (see "Links"), there have been others from the Netherlands (see "What's New", April 2002) and from France and Norway ("What's New", May 2003). Now the Swiss Federal bureau for environment, forest and landscape has released a report on high frequency radiation and health by Dr Röösli of the University of Bern and Dr Rapp of the Institute for Social and Preventive Medicine at the University of Basel. Their final conclusions are that "The survey shows that no conclusive assessment of the risk to human health may be made on the basis of present scientific data". A summary in English can be found at www.umwelt-schweiz.ch/buwal/de/fachgebiete/fg_nis/news/2003-04-14-00385/index.html
The Cellular Telecommunications
and Internet Association (CTAI) has announced funding for Phase 2 of
CRADA - the Cooperative and Development Agreement with the Food and
Drug Administration of the USA. The new research will focus on epidemiology,
and in particular on the best epidemiological tools for measuring exposure
to RF energy from wireless phones. The two funded studies are expected
to conclude by the fall of 2005. More details can be found at the CTIA
web site www.wow-com.com and at
A new study has
found no increase in the incidence
of malignant brain tumours in New Zealand since the introduction of
cell phones in 1987. This includes those sites of the head and neck
that hypothetically receive the highest levels of RF radiation during
phone use. However, acoustic
neuroma, a tumour type that has been implicated in studies by Hardell's
group (see "Research - Clinical
studies - Epidemiology"), was not included. The authors caution
that ecological studies such
as this are limited in many ways.