Cell Type-Dependent Induction of DNA Damage by 1800 MHz Radiofrequency Electromagnetic Fields Does Not Result in Significant Cellular Dysfunctions

Abstract

BackgroundAlthough IARC clarifies radiofrequency electromagnetic fields (RF-EMF) as possible human carcinogen, the debate on its health impact continues due to the inconsistent results. Genotoxic effect has been considered as a golden standard to determine if an environmental factor is a carcinogen, but the currently available data for RF-EMF remain controversial. As an environmental stimulus, the effect of RF-EMF on cellular DNA may be subtle. Therefore, more sensitive method and systematic research strategy are warranted to evaluate its genotoxicity.ObjectivesTo determine whether RF-EMF does induce DNA damage and if the effect is cell-type dependent by adopting a more sensitive method γH2AX foci formation; and to investigate the biological consequences if RF-EMF does increase γH2AX foci formation.MethodsSix different types of cells were intermittently exposed to GSM 1800 MHz RF-EMF at a specific absorption rate of 3.0 W/kg for 1 h or 24 h, then subjected to immunostaining with anti-γH2AX antibody. The biological consequences in γH2AX-elevated cell type were further explored with comet and TUNEL assays, flow cytometry, and cell growth assay.ResultsExposure to RF-EMF for 24 h significantly induced γH2AX foci formation in Chinese hamster lung cells and Human skin fibroblasts (HSFs), but not the other cells. However, RF-EMF-elevated γH2AX foci formation in HSF cells did not result in detectable DNA fragmentation, sustainable cell cycle arrest, cell proliferation or viability change. RF-EMF exposure slightly but not significantly increased the cellular ROS level.ConclusionsRF-EMF induces DNA damage in a cell type-dependent manner, but the elevated γH2AX foci formation in HSF cells does not result in significant cellular dysfunctions.

Scientific evidence contradicts findings and assumptions of Canadian Safety Panel 6: microwaves act through voltage-gated calcium channel activation to induce biological impacts at non-thermal levels, supporting a paradigm shift for microwave/lower frequency electromagnetic field action

“…Similarly, the Report correctly lists two studies by Zeni, Sannino and their colleagues as being negative for apparent genotoxicity; however, this same research group published 6 additional studies, with three showing positive effects, depending on the cell type being studied. The Xu et al (59) study found genotoxicity in two cell types but not in four other cell types. These studies clearly show that different types of cells respond differently to low level microwave exposures, but for some reason, the Panel of Experts seems unable to draw this very important conclusion.…”

Biological Effects of Cardiac Magnetic Resonance on Human Blood Cells

“…The timeframe and lasting effects of low-frequency electromagnetic fields on DNA depend on several factors, such as the cell type, the efficacy of DNA repair (consistent with H2AX dephosphorylation), the mode of exposure, the type of magnetic waves (static magnetic field, radiofrequency pulses, and gradient magnetic fields), the intensity and duration of exposure, and the use of contrast agent. [15][16][17][18][19][20][21] During CMR, all these factors can contribute at different degrees to DNA damage. Iron-mediated reactive oxygen In the study of Fiechter et al, 11 the potentially higher absorbed energy and the concomitant use of gadolinium could participate and potentiate the early onset of DNA strand breaks.…”

“…Indeed, apoptosis only seems to occur when cellular γ-H2AX levels reach specific threshold values. 16,17,19 Other intracellular abnormalities have been shown to occur during static magnetic fields with changes in erythrocyte membrane permeability, membrane elasticity, and erythrocyte sedimentation rate. 15,21 Neutrophils and monocytes displayed transient expression of activation markers.…”

Adverse Effect of Mobile Phone on Tp53, Brcai Genes and Dna Fragmentation in Albino Rat Liver

“…The altered gene expression has to negatively inflict cellular structural and its functional activity with increased tendency to tumor formation [8]. The EMR is recently classified as "possibly carcinogenic to humans" (Group 2B) as indicated by International Agency for Research on Cancer (IARC) [9]. The capacity for malignant growth is acquired by the stepwise accumulation of defects in specific genes regulating cell growth and tissue homeostasis.…”

“…The capacity for malignant growth is acquired by the stepwise accumulation of defects in specific genes regulating cell growth and tissue homeostasis. Many studies suggested that exposure to EMR was associated with a small but significant increase in the risk of cancer [9,10], which could be induced from gene mutations that resulted from DNA damage [11]. The carcinogenic process has three stages: initiation, promotion and progression.…”