The London Hazards Centre receives many enquiries from people concerned about exposure to electromagnetic fields (EMFs). Their concern is understandable since a number of research studies have suggested a link between exposure to EMFs and ill-health. Despite this, the Government insists there are no health risks and is strongly resisting pressure in the European Union for specific legislation.

What are EMFs?

EMFs occur naturally and also come from manufactured sources. Natural EMFs range from the earth's own magnetic field to waves generated by electric storms to the body's own essential electric activity. These natural EMFs are of a very low strength with a frequency of about 8 Herz(Hz) and are beneficial to health. Manufactured EMFs, which have higher frequencies, come from overhead power lines, electric wiring in buildings, electric appliances etc. It is these that are of concern.

How do EMFs affect the body?

Health risks

A number of studies have shown an increased incidence in cancers, particularly leukaemia, amongst children living near overhead power lines. Studies in Shropshire and Wolverhampton found an increased rate of depression and suicides amongst adults living near electric cable lines. Unexplained clusters of tumours, leukaemia and miscarriages have occurred amongst workers in some office environments equipped with high numbers of display screen equipment. High rates of leukaemia, breast cancer and other cancers have been found amongst workers exposed to high electric and magnetic fields.

The home and community

1. At a distance of up to 30cm:
- high intensity fields (above 40 microtesla) are generated by appliances like clock radios, dishwashers, electric hand tools, food processors and mixers, shavers, TVs, hairdriers, vacuum cleaners, sewing machines and microwave ovens.
- medium intensity fields (above 1 microtesla) are generated by some of the above appliances and others such as toasters and irons.

2. At a distance of 100cm:
- low intensity fields (under 1 microtesla) occur from all the above appliances.

In the community some intense exposure arises near overhead and underground electric power lines, and electric sub-stations.

The workplace

Official advice on EMFs

The NRPB has recommended a "safe" exposure level of 1600 microtesla for mains power frequency magnetic fields, which is so high that virtually no occupation needs to be regulated in terms of worker exposure to mains frequency EMFs.

The industry pressure group, The Electricity Association, in their 1995 "EMF Briefing", have also admitted that some scientific studies make connections between exposure to EMFs and diseases such as leukaemia and brain cancer. Despite these admissions, those involved in electricity generation, distribution and supply are keen to encourage the belief that EMF exposure is not connected to human diseases and illnesses and that manufactured EMFs are covered by naturally occurring EMFs and made harmless.

Minimising exposure

Electric fields can be shielded against easily and cheaply in new buildings and equipment. Magnetic fields are best dealt with by designing them out or shielding them where they are generated. Once they leave their source it is very difficult to shield them effectively.

Only if the above cannot be achieved should the key principles of minimising exposure listed below be applied:
a) use low voltage and shielded equipment
b) cut off the current and unplug equipment when not in use
c) keep your distance

Action at home and in the community

try to assess what external sources of EMFs there are eg overhead and underground cables, the proximity of electric substations; you may be able to get relevant information from the industry bodies, the Energy Networks Association (020-7706-5100) and the Energy Retail Association (020 7747 2932). for independent (but not free) advice on EMF problems and comment on surveys call the Electromagnetic Hazard and Therapy Help Line, 0906 4010237 (£1.50 per minute). for useful independent publications and EMF meter hire contact Powerwatch (01353 778814). you can take action to prevent a sub-station or pylon from being installed nearby or to have them removed. Some solicitors experienced in environmental legal issues have taken on and won cases of this kind, although there is no guarantee of winning. unplug electric appliances and transformers when not in use. ensure that places where you spend long periods of time are at least 4 feet from appliances that are "working" e.g. electric clocks, radios, televisions, immersion heaters, storage heaters, sewing machines and electric fires. use low voltage battery driven equipment where possible. try to ensure that mains adapters/battery eliminators are not next to your bed. arrange lounge seating and beds so that your head is not close to wiring circuits in walls, especially common service wiring routes in blocks of flats. unplug electric overblankets or underblankets before going to bed. remember that walls don't significantly reduce EMFs; ask yourself, "what is on the other side of this wall from my body".

Action at work

follow the principles set out above. use the legal rights in the Safety Representatives and Safety Committees Regulations 1977 to take up health and safety concerns with your employer (see Daily Hazard No.42). ensure that your employer's risk assessments under the Management of Health and Safety at Work Regulations 1992 include the risks of EMFs. if your employer is planning a new building, follow the example of the World Bank and ensure that EMFs are minimised. ensure your employer selects equipment with low emissions. ensure your employer selects equipment which does not generate strong magnetic fields. ensure that VDUs meet Swedish MPR II standard as a minimum. The Swedish TCO 92 standard is better but not as readily available. ensure the workplace is screened with good electric conducting plates. switch off, unplug or isolate electric equipment from its power source whenever possible. keep your distance from EMF generators.

LHC Members