Cell type-dependent induction of DNA damage by 1800 MHz radiofrequency electromagnetic fields does not result in significant cellular dysfunctions.
BACKGROUND
Although 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.


OBJECTIVE
To 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.


METHODS
Six 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.


RESULTS
Exposure 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.


CONCLUSIONS
RF-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.
Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.
Shanshan
S
Xu
Guangdi
G
Chen
Chunjing
C
Chen
Chuan
C
Sun
Danying
D
Zhang
Manuel
M
Murbach
Niels
N
Kuster
Qunli
Q
Zeng
Zhengping
Z
Xu
D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004249:DNA Damage; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011846:Radio Waves / Q000009:adverse effects*; D017382:Reactive Oxygen Species / Q000378:metabolism
D017382:Reactive Oxygen Species