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Wireless phones have greatly improved our ability to communicate with each other. Concerns have been expressed, however, about possible health risks associated with their use. Wireless phones transmit and receive electromagnetic waves in the radiofrequency (RF) part of the electromagnetic spectrum. The frequency of these waves lies in the approximate range 800 million Hertz (800 MegaHertz) to 2 billion Hertz (2 GigaHertz). The antennae of base stations radiate the waves. The power output of the antennae is 100 Watts or less. Biological
effects of radio wave radiation are very different from those seen with
radiation in the so-called ionising part of the electromagnetic spectrum
for example, x-rays in that they are not thought to disrupt
chemical bonds or have direct effects on DNA.
Radiowaves can cause motion of electrical charges and convert energy
into heat. As discussed above, this well-established "thermal biological
effect" is the basis for the guidelines that have been put in place
to ensure the safety of those exposed to radiowaves, both in everyday
life and in the workplace. Major
international studies are planned, including several which will examine
possible associations with cancer. Particularly noteworthy is the World
Health Organisation International EMF Project which started in 1996.
These studies are discussed in greater detail under "Reseach
Programs ". The Table shows that the incidence and mortality rates of brain cancer and leukaemia (another cancer that has been claimed by some to be associated with RF radiation) have not risen in tandem with the proliferation of a wide range of EMF exposures in Canadian society. Compared to other cancers, the rates for leukaemia and brain cancer are relatively low in the Canadian population. In 1995, the age-standardized incidence rate for lung cancer among men was 84/100,000 and among women was 40/100,000, and the respective mortality rates were 73/100,000 and 31/100,000 (National Cancer Institute of Canada, 2000). Among men, the incidence rate of prostate cancer was 110/100,000 and the mortality rate was 33/100,000. Among women, the incidence rate of breast cancer was 98/100,000 and the mortality rate was 28/100,000. Breast, lung, and prostate cancers, as well as cardiovascular disease and injuries, significantly contribute to the total burden of disease in Canadian society. Trend
of Incidences and mortality in brain
These examples illustrate the quantitative assessment of a possible public health hazard. A health hazard/benefit assessment must include estimations of the potential impact to the general public as a whole, as well as to relevant population groups. As Valberg (1997) stated: "undue anxiety can be averted by emphasizing that our current knowledge indicates that lifestyle, diet, genetic factors, and improved healthcare have a far more significant effect overall on human health than hypothetical risks such as RFR." Others have argued that the emerging technology of wireless communications demands the invocation of the precautionary principle. This asserts that "the burden of proof for potentially harmful actions by industry or government rests on the assurance of safety and that when there are threats of serious damage, scientific uncertainty must be resolved in favour of prevention" (Goldstein, 2001). The Independent Expert Group on Mobile Phones in the UK (2000) recommended that "a precautionary approach to the use of mobile phone technologies be adopted until much more detailed and scientifically robust information on any health effects becomes available". Most scientific bodies have recommended continued surveillance of disease trends as part of a responsible public health program, since personal wireless telecommunications were introduced to the general public relatively recently. There is a need for further well designed studies (Jauchem, 1998), and, as mentioned earlier, a large number of studies are underway at this time.
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