The short answer is no, RF radiation from PCS and cellular stations do not cause cancer. There has been a few epidemiological studies such as the one done in Sutton Coldfield, Great Britain, that would suggest a weak association between proximity to TV towers and an increase in cancer incidence [1]. However, more rigorous follow-up studies based on these findings have revealed no link between cancer and RF radiation [2]. While the follow up studies do not in themselves show that cancer and RF radiation are not correlated, the idea that cellular and PCS towers do not cause cancer is supported by the research of others. Numerous studies conducted in vitro (in isolated cells) and in vivo (in organisms) involving RF radiation exposures of varying strength and duration all agree that RF radiation is not a carcinogen in itself.

Even though RF radiation does not play a direct role in carcinogenesis, there is some evidence that it may influence the development of a pre-existing tumor . There are two main associations that have been made between RF radiation and cancer growth. The first discovery is the apparent ability of high levels of RF radiation to act as a promoter of cancer. Studies in vitro show that if a cancer gene and its promoter (a portion of DNA that "promotes" the activity of a specific gene) is introduced into a cell, the addition of RF radiation will cause the cancerous cell to grow at an accelerated rate [5,6]. Similar research with mice has likewise demonstrated that tumors transplanted or induced into animals will also have an increase in proliferation [4,7].

A second observation involving the role of RF radiation in tumor development may initially seem somewhat contrary to the first. Several studies have actually shown an increase in cellular resistance to cancer after exposure to RF radiation. In vitro exposure to RF radiation actually reduces the rate at which the cancerous cells multiply [5]. The key here is that no promoter has been added to the cell. Studies in vivo show that mice exposed to RF radiation acquire a certain resistance to cancer [8]. Resistance was also conferred upon mice who were exposed to RF radiation during the fetal stage. However, it is important to note that those few exposed mice that did succumb to cancer developed tumors at an accelerated rate.

While the exact reason why RF radiation seems to enhance tumor growth and cancer resistance in these experiments remains unclear, the most plausible explanation provided by the scientists is thermal. One of the well-documented effects of high levels of RF radiation is to elevate the temperature of the system under consideration. Since it is well known that an increase in temperature corresponds to an increase in cellular biological activity, it has been proposed that the higher temperatures induced by RF radiation causes cells to proliferate at an faster rate. Likewise, the resistance of the irradiated mice to tumor development can also be explained in terms of heat. Higher temperatures accelerate the activity of the immune system in an organism. Since the immune system is responsible for fighting infection and cancerous cells, an increase in its activity would naturally correspond to an increase in tumor resistance.

It is extremely important to remember however, that all of the experiments mentioned in this section exposed cells and animals to levels of radiation far, far greater than the output of even the most powerful PCS and RF stations.

Although recent research would suggest that RF radiation plays no direct role in inducing cancer, these studies do not imply that it is completely passive. Indeed, there is definite evidence that RF waves are responsible for a variety of effects at the cellular level. These include changes in cell membrane charge distribution and ion channel permeability, degradation or expression of cellular proteins, and acceleration of cell metabolism. Although such studies are too numerous to list completely here, a few will be mentioned to give a general idea of the findings. It is important to remember that in all cases, the level of RF radiation under study is significantly greater than the power output of a cell or PCS site.

Several studies have discovered that high levels of RF radiation tend to result in an increase in Ca²&sup+; activity in the cell [13, 14, 15]. While the full uses of calcium ions in the cell are not completely known, it has long been held that calcium plays a role in secondary messenger systems, changing the level of activity of certain enzymes (which are molecules that help to speed along certain chemical reactions). Consistent with this finding are several others that report changes in enzyme activity.

High levels of RF radiation can modify the activity level of certain enzymes. For example, ( - galactosidase expression is increased [16, 17, 18] when cells are exposed to certain frequencies of RF radiation. Similarly, acetylcholinesterase activity was increased [15] at particular frequencies. It is not true to say that all enzyme activity is increased, however. There are studies that have shown a decrease in certain enzyme when cells are exposed to high level of RF radiation at specific frequencies. For example, a study has found that ATPase activity in human red blood cells decreases with RF radiation exposure [19]. Unfortunately, the mechanisms for many of these findings are at this time still unknown. There is no doubt however, that with increased research and the passage of time our understanding of these effects will increase greatly.

Not necessarily. There are several variables that must be given full consideration before speculation can be made on whether or not wireless technology is worthy of public concern. First, we must look at how well the experiments in RF radiation model reality. Often, in research regarding new technology and scientific discoveries, scientists will expose the cell, tissue, or animal to levels of the phenomenon in question far, far greater than what would be experienced in real life. It is difficult to extrapolate that a small amount of anything is harmful just because an extreme amount of that something yields mixed results. For example, let us consider exercise. It is a widely established belief that running one mile a day will not kill the average person; indeed, such activity may be considered healthy. Yet, suppose you were forced to run not one, but one million miles non-stop. Even if you are an Olympic athlete, you're going to be dead after the first several dozen if you don't stop at some time. The point is, too much of anything -even a normally good thing- can be bad for you. In many of the experiments performed, the levels of RF radiation exposure studied are often several orders of magnitude larger than what the average civilian sitting at home would encounter, even considering the cumulative effects of TV, radio, cellular, and PCS technology. Incidentally, of the four, the latter two combined contribute less than 0.0002 % of the total RF radiation [20].

The second fact that we must consider is the outstanding ability of biological organisms to adapt to the environment. Luckily for us, our bodies are more than capable of dealing with the minor stresses caused by non-ionizing RF waves. Scale is key. While RF radiation may break down a cellular protein or change enzymatic activity every once in a while, our bodies posses so many trillions of cells, each manufacturing billions of proteins, that the loss of one, a thousand, or even a million will not be missed. In the time it took you to read this passage, thousands of your cells died and were replaced [21]. Daily activities such as walking around in the sun and eating rice or charcoal-broiled steak -all of which are carcinogenic- cause many of your cells to mutate, become cancerous and be removed by your immune system [23]. At the end of each day, you permanently lose a few million brain cells [22]. And what is the effect of all this cellular death and mutation upon you as an organism? Nothing. Hence, while the theorized loss of a few proteins due to RF radiation may seem alarming initially, we see that it really is insignificant in the grand scale of your body as an entity.

There is a great deal of research that has found no evidence of RF radiation having any effect on DNA, the double-helical molecular chain which defines cellular function and an organism's characteristics [3,9, 10, 11]. Because of the importance of DNA, it is one of the most resilient structures in the cell.

While the general consensus among the scientific community is that RF radiation has no significant effect on DNA, there are a few studies which have found slight responses of DNA to RF radiation exposure. It is contended, though yet uncertain, that RF radiation does cause some uncoiling of naked DNA [12]. Since the term "naked" refers to the fact that the DNA has been extracted from the cell and isolated, it is still unknown whether or not RF radiation causes similar changes in the cell or in vivo. Nevertheless, the evidence is still overwhelming in favor of RF radiation having no effect [3].