Electromagnetic Fields
An examination of the basic principles, the animal/laboratory data and human epidemiological studies as they relate to Vodafone base stations used in the telecommunications industry in Ireland.
Monday 2 February 1998
The report is divided into three sections. The first section describes the basic physical principles involved in the operation of a telecommunications base station. Beginning with an explanation of the electromagnetic spectrum the report goes on to define the concepts of transmitter power, power density, equivalent isotropic radiated power (EIRP) and specific absorption rate (SAR). Definitive figures are given for exposure limits set by various regulatory bodies such as the International Commission on Non-Ionising Radiation Protection (ICNIRP).
In addition, comparisons are made between the power densities emanating from other sources which operate at frequencies close to that employed by Vodafone (950MHz), such as UHF TV and microwave ovens.
The actual power densities which were measured at a telecommunications base station and reported to Forbairt are used to demonstrate that (even when a telecommunications base station is operating to its maximum capacity) the measured power density impinging on the most exposed member of the public is still 1300 times lower than the guidelines laid down by regulatory bodies.
The second section of the report deals with the biological effects of radiofrequency energy in animals and laboratory models - colonies of cells grown in appropriate culture media. The group concludes that there is no definitive evidence that radiofrequency (RF) exposure in the spectrum at the frequencies used by the telecommunications industry will result in alteration to DNA structure.
Various experiments have included overall general health and longevity, tumour growth, blood-brain barrier permeability, etc., and while there have been conflicting results, there is still no unequivocal evidence of a 'cause and effect' relationship between RF exposure and development of cancer in animals.
The final section of the report is about the evidence of health effects in human beings exposed to radiofrequencies, and in particular the most relevant studies on the health effects of extremely low frequency EMF in children are also discussed. Analysis of the studies on EMF exposure in adults is also presented. The most important and relevant of the studies discussed are those reported by Dolk, et al (1997 a,b), in which no evidence for an increased risk of cancer around TV and FM radio transmitters was found. This strongly suggests that the increased risk is not caused by transmitters. A typical television and FM radio transmitter is very much more powerful than a mobile base station.
Conclusions of this independent report on Vodafone base stations and health:
Vodafone telecommunications masts (950MHz) emit power similar to that emitted by UHF television transmitters, microwave ovens and radar systems
All main FM radio transmitters are 7-8 times more powerful than an Vodafone telecommunications mast
The level of radio waves given off by Vodafone base stations is 1300 times lower than the standard set by the ICNIRP
Well-designed studies have failed to show that there is any link between RF exposure and the subsequent development of cancer