Upcoming Events

Mini Calendar

< >
December 2018
Su Mo Tu We Th Fr Sa
1
2345678
9101112131415
16171819202122
23242526272829
3031

Health

Electromagnetic Fields, Radiation and Health

EMF Overview

When electric current flows in a conducting material, a magnetic field is created, and the greater the current, the stronger the magnetic field. ElectroMagnetic fields (“EMFs”) are found everywhere in our environment, but during the 20th century, the exposure to man-made EMFs (particularly alternating current EMFs) has been continuously increasing with the growing demand for electricity and increasing use of electrically powered technology. Low frequency electric fields influence materials that contain charged particles, including the human body. EMFs creates circulating currents within the human body, where the strength is dependent on the intensity of the EMF. It is well understood that EMFs above certain levels can trigger biological effects, so the debate is whether long?term, low level exposure can influence people's health and wellbeing.

The potential health effects of exposure to EMF are much debated, giving rise to lots of controversy. With EMF being one of the most common environmental influences in everyday life, there is a lot of anxiety and speculation in the general population.

Measurements

Electric fields are usually measured in volts per metre (V/m) or for large fields kilovolts, where:-
 1 kilovolt per metre (kV/m) = 1000 volts per metre

Magnetic fields are usually measured in microteslas (µT) or milligauss (mG) where:-
  1 microtesla = 10 milligauss

 

EMF and Health Issues

Although much controversy exists, and the data is in most cases is inconclusive, many health authorities now recognise that there is a possible link between EMF exposure and childhood leukaemia. This link was first proposed in a 1979 publication (Wertheimer N & Leeper), and has since been studied extensively. There have been several comprehensive reviews, meta-analyses and some pooled analyses. In one pooled analysis based on nine studies, a twofold risk was reported for exposure above 0.4 µT/ 4 mG (Ahlbom A et al. 2000). Another pooled analysis including 15 studies found a relative risk of 1.7 for exposure above 0.3 µT/ 3 mG (Greenland et al. 2000).

More recently, a study by Henshaw (2005) reported that children in England and Wales who grew up within 600 m of a high voltage overhead power line had a higher risk of childhood leukaemia.

Recent studies have looked at the potential of DNA damage (Yang et al. 2008) and a hypothesis that magnetic fields suppress the nocturnal production of melatonin in the pineal gland (Henshaw & Reiter 2005) as a cause for the observed increased risk of childhood leukaemia.

There are also theories suggesting that high voltage powerlines emit corona ions, small electrically charged particles which are emitted from powerlines. These ions may then attach themselves to particles of air pollution which can be inhaled (Henshaw et al. 2008).

Alzheimer was first suggested to be affected by EMF in 1995 (Sobel et al. 1995). This connection has recently been shown in a Swiss study showing a significant dose-related increase in deaths from Alzheimer’s disease in people who have lived for a number of years within 50 m of overhead powerlines (Huss A et al. 2009). The latter study found a similar pattern for senile dementia and EMF. Some studies have also suggested a relationship between EMF and adult leukaemia, adult brain cancer and various other cancers and illnesses, however, these are less conclusive.

There have also been speculations that EMF may be linked to miscarriages, birth deformities and low birth weight, alongside general health complaints such as migraine and sleep disturbance, and even suicide. However, at this point, most health authorities agree that there is not enough evidence to draw strong conclusions.

The World Health Organisation claims that there is “limited evidence” to support the correlation and that more research is needed. It should be noted the distinction between having evidence and assuming no effect. As a response to the evident rising public concern over health effects of EMF exposure, the World Health Organization (“WHO”) in 1996 established the International EMF Project. The EMF Project not only supports research in order to fill important knowledge gaps, but has also made possible the development of internationally acceptable standards to limit EMF exposure.

Standards for EMF Exposure

There is currently a trend for many health authorities in western countries in particular to take a more precautionary approach, above the ICNIRP standard, and to acknowledge the potential risk of EMF to human health:

  • The Stakeholder Advisory Group on ELF EMFs (SAGE), set up by the UK Department of Health, have looked at possible implication of EMF exposure and made some practical recommendations to limit exposure, which included laying new power lines underground where possible;
  • A 2004 European Union REFLEX report found that exposing cells to EMF resulted in a significant increase in DNA damage, and the damage could not always be repaired by the cell itself. Future generations of cells showed damage as well, and the damage appeared more distinct in older subjects. Other reported results included damage to chromosomes, an increased rate of cell division and alterations in gene activity;
  • The Italian Ministry of the Environment in 2000 announced a goal of a maximum EMF of only 2 mG /0.2µT) in new schools, kindergartens and playgrounds when built next to power lines;
  • The Swiss government in 1999 issued a recommendation of no more than 10 mG/ 1 µT for human EMF exposure in new developments.

Australian Standards

Australia has adopted the standards from the ICNIRP guidelines, with 1000mG/100 µT for the general public and 5000mG/500 µT for occupational exposure. Australia’s standards are voluntary. It is understood that work is still underway for new EMF standards by the Australian Protection & Nuclear Safety Agency (“APANSA”).

Exposure duration is important and currently the National Health and Medical Research Council (NHMRC) guidelines recommend the following limits of exposure*:

  • Public exposure to magnetic fields 1 000 milligauss continuous or 10 000 milligauss for up to 2 hours/day
  • Occupational exposure to magnetic fields 5 000 milligauss (for a working day) or 50 000 milligauss for up to 2 hours/day
  • Public exposure to electric fields 5 kV/m continuous or 10 kV/m for up to 2 hours/day
  • Occupational exposure to electric fields 10 kV/m for a working day or 30 kV/m for 2 hours/day

* source Energex website & Energex claims that all of its powerlines comply with these exposure guidelines. We certainly hope so as they are considerably higher than those required in other countries.

For 110 KV powerlines Energex currently specifies a minimum easement width of 40 metres ( ie 20 metres either side of the centre line) with overhead powerlines supposed to be kept a minimum of 20 metres away from homes or places of continuous or extended periods of occupation.

Researchers are discovering more and more associated illnesses and chronic diseases associated with EMF's, however it does take time to research and convince government or industry of these dangers. In many respects this situation could be similar to asbestos and smoking related disease, where the causes are difficult to prove and the impacts take many years to develop.

Their are also many books on this subject and lots of information on the internet including...>http://www.emfs.info/