Low level EM fields pose little health risk, says IEE

Low level electromagnetic (EM) fields are a low risk, although more research should be conducted, according to the IEE.

“After analysing the past two years of peer-reviewed literature on the topic, the group’s conclusion is the same as that reached in its last statement in 2002, said chairman Prof Anthony Barker from the Royal Hallamshire Hospital in Sheffield.

The group concerned is the IEE’s policy advisory group on biological effects, which has been studying the effect of low level fields up to 300GHz on humans.

“The absence of any new and robust evidence of harmful effects is reassuring,” said Barker.

“The cumulative evidence from a large body of research compiled in the past 20 years suggests, in general, that the existence of harmful health effects is unlikely,” he added.

However, pooled analysis of epidemiological studies suggests an association between higher magnetic field levels at power frequencies and childhood leukaemia, said the IEE.

Although the raised risk was relatively low, the advisory group supports further epidemiological and laboratory-based research to investigate its relevance to human health.

A causal link between leukaemia and electromagnetic fields has not yet been shown, said Barker, and the group recommends isolated reports of biological effects or epidemiological findings be treated with caution until confirmed by an independent group.

A copy of the report can be found here.

Setting the limits of EM

There was a call last month for stricter limits on exposure to electromagnetic fields from sources of up to 300GHz by the UK’s National Radiological Protection Board (NRPB).

The NRPB says the UK should adopt guidelines issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), which cover a range of frequencies, taking in fields emitted by 50Hz high power electricity lines and mobile phones. Both have come under scrutiny in recent years.

The ICNIRP publishes two sets of exposure limits, one for people at work, the other – two to five times lower – for the general public.
For 50Hz power lines the limits for the general public are: electric field 5kV/m; and B-field 100µTesla.

At GSM’s 900MHz the limits are 41V/m and 0.14µT, with a maximum power density of 4.5W/m². The microwave limits aim to reduce body heating effects.