Cancer Myth:Power Lines and cancer
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Origin of the myth
All radiation causes cancer. It is no surprise that radiation has a bad reputation. High-energy radiation (ionising radiation) - such as x-rays, and (gamma) γ-rays (which are
emitted by nuclear explosions) - has been shown to cause cancer, genetic defects and
weaken the immune system.
It makes sense therefore that the media, and public perception, has extended this bad
reputation to low-energy radiation (non-ionising radiation) – such as extremely-low-frequency (ELF) radiation (electricity), radiofrequency (RF) radiation and microwaves.
Major sources of public concern have been powerlines, mobile phones and their base
stations.[1]
High-energy radiation (ionising radiation) alters (ionises) chemical and molecular bonds and can do damage to molecules such as DNA (genetic material in cells). This is the cause of cancers and genetic defects. Low-energy radiation (non-ionising radiation) does not have the right frequency or sufficient energy to ionise molecules. There is little basis for the theory that it can damage DNA.[1]
Current evidence
Electric and magnetic fields exist wherever electricity is conducted through
transmission lines or used in appliances. These fields have a frequency (wavelength) of
50 to 60 Hertz (Hz) which is relatively low. Hence, these fields are called extremely-low-
frequency (ELF) fields.[2]
IARC, an agency of the World Health Organization (WHO), classifies low frequency fields
as ‘possibly carcinogenic [cancer-causing] to humans’ – the lowest of three levels of
carcinogenicity – and the same classification as coffee.[2], [3]
This classification means that there is:
- Limited evidence of carcinogenicity in humans
- Less than sufficient evidence of carcinogenicity in animals
This rating is based mainly on two recent studies that suggest an increase in childhood
leukaemia in populations with higher exposures to ELF fields. Adult studies do not
provide enough information or are inconsistent on the effects of ELF on cancer.[2], [3]
The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) asserts that
despite numerous studies been done, there is no conclusive evidence that ELF causes
cancer. EMF studies show either weak or no association with adverse health effects.[4]
The Report on Carcinogens (ROC) is a list of known or reasonably anticipated human
carcinogens. ELF fields and radiation are not included in this list.[5]
Summary
There is limited evidence, for childhood leukaemia, of a link between power lines and cancer. To date there has not been a definitive link proven, but it remains an active area of research internationally.
References
1. Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). Radiation
basics - ionising and non-ionising radiation. 2004 [cited 2008 02/01/2008];
Available from: http://www.arpansa.gov.au/radiationprotection/basics/ion_nonion.cfm.
2. World Health Organization (WHO). Electromagnetic fields and public health: extremely low frequency fields and cancer. 2001 [cited 2008 02/01/2008]; Available from:
http://www.who.int/mediacentre/factsheets/fs263/en/.
3. International Agency for Reseach on Cancer (IARC), Non-ionizing radiation, part 1:
Static and extremely low-frequency (ELF) electric and magnetic fields, IARC, Editor.
2002, IARC: Lyon, France.
4. Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).
Electromagnetic fields and possible adverse health effects. 2007 [cited 2008
02/01/2008]; Available from:
http://www.arpansa.gov.au/radiationprotection/FactSheets/is_emf.cfm.
5. U.S. Department of Health and Human Services, 11th Report on Carcinogens. 2005,
Public Health Service - National Toxicology Program,.
