31/03/2004 - UK NRPB adopt ICNIRP Guidance levels
UK NRPB adopt ICNIRP Guidance levels
Today the UK NRPB announced that they are adopting the ICNIRP non-ionising
guidance levels. They describe this as "precautionary", but it is difficult to
see why or how it is. In the past they have resolutely stuck to the ICNIRP
occupational exposure levels also for the general public and have not applied
the further precautionary factor of typically 5, because they correctly stated
that this extra factor was not justified by the science. The NRPB adopted the
ICNIRP levels for the mobile phone bands in 2000 after the UK IEGMP (a.k.a.
"Stewart") Report suggested that they did so, but they did not adopt them for
However, in the introductory "Board Statement" they do admit for the first
time that power-frequency magnetic fields have been associated with an increased
risk of childhood leukaemia and that the need for further precautionary measures
should be considered by government. This is an excellent improvement on previous
Board Statements and is likely, in part, to be due to the more pro-actively
precautionary attitute of the new NRPB Board Chairman, Sir William Stewart. The
Board advice is played down by terms such as "intense" (0.4 microtesla is
"intense" ?? - but they set their new guidance level at 100 microtesla!)
and "small" (is a doubling "small?") and "reasons that uncertain", but in
the body of the document the increased risk is more genuinely defined. This is
Both ICNIRP and the old NRPB levels are based on old, well established,
science and proven gross effects such as electrocution and tissue heating. They
generally agree on the levels for occupational exposure. This is set
approximately 10 times below the level of gross, acute, harm. ICNIRP then adopt
a further small factor for protection of the general public.
Neither the ICNIRP nor the old NRPB levels were based on possible long-term
effects such as cancer, depression, suicide, miscarriage, etc - i.e. the
guidance was not even intended to protect against these effects at all. So by
adopting ICNIRP for the general public exposure guidance the NRPB have not
really moved forward in any practical way from their previous guidance.
For example, at the 50 Hz mains electricity power frequency the guidance
level comes down from 1600 microtesla to 100 microtesla. This sounds a big
decrease - and it is - but not a practical one. Even under the largest, highest
power overhead pylon power-line the 50 Hz magnetic field rarely exceeds 25
microtesla, and never exceeds 50 microtesla in places with public access.
Typical highest fields are in the range 0.5 to 15 microtesla. UK household
levels away from powerlines and underground cables are typically 0.03 to 0.05
Even the NRPB, in this new Guidance, Docs NRPB 15-2, describes 0.4 microtesla
as an "intense magnetic field", so it is difficult to see how they think a limit
of 100 microtesla will protect the public in any meaningful way. Countries such
as Italy and Switzerland that have precautionary guidance have set levels
between 0.2 and 1 microtesla as the maximum public exposure from new
installations or in new houses and schools.
The NRPB do admit that a doubling of childhood leukaemia has been found in
magnetic field levels of 0.4 microtesla and above. They, slightly misleadingly,
say this increases the risk from 1 in 20000 to 1 in 10000 per year. They fail to
point out that this is over 15 years of childhood, so the risk to any one child
during their childhood increases from 1 in 1330 to 1 in 670. CHILDREN with
LEUKAEMIA are holding a 5-day scientific
conference in Westminster, London, in September 2004, to examine all the
possible causes of childhood leukaemia with the specific aim of trying to find
ways of stopping the increasing incidence of childhood leukaemia which has
become the UK's biggest childhood killer disease.
They try to dismiss the importance of the electricity-childhood leukaemia
association by saying that it only increases the annual 500 UK childhood
leukaemia cases by 2. However the latest molecular genetics shows conclusively
that the initial genetic damage is done in utero (i.e. in the womb) and so if
the power-frequency magnetic fields (EMF) link is real (as we believe it is)
then much of the genetic damage may be due to EMF exposure of the mother before
the child is born. This has never been investigated. This is more likely because
two recent studies linked miscarriage with maternal EMF expsoure over 1.6
microtesla - over 60 times lower that the new, so called precautionary, NRPB
advice. Now, miscarriage may occur when the damage is too great for the foetus
to stay viable, but lesser damage may result in the leukaemia genetic marker
damage. Much more scientific and medical work needs to be done on this, but the
indications are that for advice to be precautionary the maximum exposure
guidance level for the general public would need to be around 0.2 microstesla.
We will add more comments here on this site on the NRPB advice during today
(Wednesday 31st March).
Watch and listen
to Jon Kay.
P5/04 31st March 2004 on the NRPB website
is their Press Release which inlcudes links to download the documents.