3. Animal studies

Such traditional models rely heavily on DNA damage and the subsequent clonal expansion of mutated cells for their modality. In the past, it has been stated that no mechanism is known to cause cancer in the nonionizing radiation or radiofrequency radiation part of the electromagnetic spectrum since it does not damage DNA or cells directly like ionizing radiation [10]. Thus, it has been largely dismissed as a putative cause of cancer. However, recently, it has become apparent that the pathogenesis of cancer is closely connected with aberrantly regulated apoptotic cell death and the resulting deregulation of cell proliferation. A mechanism for gamma-radiation carcinogenesis based on an apoptotic model has already been proposed [11]. According to a new approach to cancer risk assessment, it was determined that EMR from cellphone towers may pose a cancer risk in humans since microwaves can stimulate p53-mediated caspase-3 activation and cell death in a human brain glioblastoma cell line [12] and Fas-induced and ERK-mediated apoptosis in human lymphocyte cell

Aside from the Moscow study of the US Embassy staff, early epidemiological data were gathered from technically trained US naval officers routinely exposed to radar by Robinette et al. [15]. Radar transmission generates electromagnetic waves in the microwave domain. Interestingly, both these groups showed an elevated incidence of leukemia. In another large Polish study, military personnel exposed to radiofrequency microwave radiation from radio

The first epidemiological studies on populations living near cell base stations focused mainly on cognitive changes and neurobehavioral effects and started being conducted in 2002 [17]. However, an early Egyptian cellphone tower study in the Algharbia governate area (1999–2002) suggested an increase in the overall cancer rate of the local population by 7.5% [18]. Later, a German study found elevated cancer incidence in patients who had lived 5–10 years within 400 meters of a cell installation [19]. Another Israeli study indicated an association between increased

There also appears to be a significant body of evidence suggesting that cell phones, which use EMR in the microwave range, can cause brain tumors and disturb brain function [21, 22]. One Swedish study reported that cellphone radiation increases the human brain tumor rate by 2.5 times [23]. In fact, in his extensive review on the subject, Cherry concludes that over 40 studies have revealed adverse biological or human health effects specifically from cellphone radiation and that there is extremely strong evidence that cell sites are risk factors for brain tumors and

It should be noted that children may be more susceptible to damage from cellphone radiation since their bodies are still developing. There is epidemiological evidence to suggest that children are susceptible to leukemia from high power voltage (HPV) lines which emit lowfrequency radio waves [25, 26]. Although no epidemiological data seem to have been collected

and radar showed very significant elevations in leukemia and other cancers [16].

cancer incidence and living in proximity to a cell base station [20].

lines [13, 14].

leukemia [24].

2. Epidemiology

140 Current Understanding of Apoptosis - Programmed Cell Death

In vivo animal studies have demonstrated that potentially genotoxic effects in male Wistar rats following microwave exposure include the induction of micronuclei, an increase in the production of reactive oxygen species (ROS) which can trigger cellular apoptosis, and increases in various antioxidant enzyme activities like serum glutathione peroxidase, superoxide dismutase, and catalase [2]. Rats exposed to microwaves display a significant reduction in splenic activity of natural killer cells, which may help to provide host defense against the development of tumors [30]. Other cellphone radiation research in animals has shown that it doubles the cancer rate in mice [31]. Also, EMR from cellphones can increase mouse tumor necrosis factor (TNF) production, which is associated with a major apoptotic pathway [32]. Cellphone radiation increases the embryonic mortality of chickens [33].

In vitro, one very elegant set of comparative studies correlating results in human lymphocytes with Chinese hamster cells (V79) has suggested that microwave radiation can induce structural damage in mammalian chromosomal DNA. A significantly higher frequency of specific chromosome aberrations, such as dicentric and ring chromosomes, was observed in irradiated V79 cells than in control samples. Micronuclei were also present in the irradiated V79 cells [34]. Animal studies have demonstrated the neoplastic transformation of a clonal mouse embryo cell line (C3H/10 T1/2) following exposure to modulated microwaves [35]. In other more recent studies, neural cell apoptosis in NGF-differentiated PC12 rat cells has been induced by microwave exposure via the mitochondria-dependent caspase-3 pathway [36]. It represents one of three cellular apoptotic pathways including the extrinsic death receptor-dependent pathway, the intrinsic mitochondria-dependent pathway, and the intrinsic endoplasmic reticulum(ER) stress-mediated pathway [37].
