Written by Angeline A. De Leon, Staff Writer. This study demonstrates that mobile phones when used for prolonged periods can cause genotoxicity and that headphone use reduces the harmful effects of mobile phone radiation.
Recent reports estimate that there are more than three billion current mobile phone users worldwide 1. Depending on the country and network, mobile phones emit and receive microwave radiation in the frequency range of 900 to 1800 MHz, and although there has been debate regarding the health risks associated with cell phone use, emerging research now suggests that mobile phone radiation may be linked to genotoxic effects (involving damage to cellular DNA) 2-4. In fact, as of 2011, mobile phone radiation has been classified by the World Health Organization as possibly carcinogenic due to increased risk of glioma (a malignant tumor of the glial tissue of the nervous system) 5. Particularly vulnerable to the effects of cell phone radiation is the oral mucosa, the mucous membrane lining the inside of the mouth, due to the direct proximity of the neck and head to the mobile device during use. However, the carcinogenic effects of mobile phone radiation on the oral epithelium is largely mixed 6,7. In a study 8 published by the Journal of Clinical and Diagnostic Research, investigators conducted a comparative evaluation between low vs. high mobile phone users on the formation of micronuclei (MN, extra-nuclear bodies containing damaged chromosome fragments, measured as a marker of DNA damage/genotoxicity) in oral mucosal cells 9.
Participants in the cross-sectional study consisted of 300 male subjects (aged 20-30 years), half classified as low mobile users (cell phone users for less than five years reporting less than three hours of receiving/making calls on mobile phone weekly) and high mobile users (cell phone users for over five years reporting more than 10 hours of receiving/making calls on mobile phone weekly). High mobile users were further classified based on whether or not they used wired headphones (headphone users = 70, non-headphone users = 80). For all participants, exfoliated buccal mucosal cells were collected from the side which subjects reported using most during cell phone calls. Cells were screened and stained with DNA-specific solution, and the number of positive MN counted.
Analyses indicated that mean MN frequency was significantly increased in high mobile users (1.52 +/- 1.76), as compared to low mobile users (0.77 +/- 0.815) (t = 6.4199, p < 0.001). In high mobile phone users, mean MN count from the side nearest to the mobile phone during use was observed to be statistically higher (1.52 +/ 1.76), relative to the opposite side (0.90 +/- 0.3992) (t = 14.1024, p < 0.001). In addition, non-headphone users exhibited a significantly higher MN count (2.08 +/- 1.291), compared to headphone users (0.96 +/- 0.699) (t = 6.2677, p < 0.001), and among non-headphone users, those who complained about warmth around the ear also showed the highest mean frequency of MN cells (2.847 +/- 0.341).
Results suggest that prolonged exposure to mobile phone radiation, even within the range permissible by the International Commision on Non-Ionizing Radiation Protection group, may be associated with signs of DNA damage. Based on findings, it would be advisable to take simple precautionary steps, such as distancing the phone from the body during mobile use or connecting via headphones, in order to reduce the harmful effects associated with mobile phone radiation. Randomized controlled trials are needed to confirm study findings and to examine what other areas of the body may be vulnerable to the genotoxic effects of mobile phone use.
Source: Banerjee S, Singh NN, Sreedhar G, et al. Analysis of the genotoxic effects of mobile phone radiation using buccal micronucleus assay: a comparative evaluation. J Clin Diagn Res. 2016; 10(3): ZC82–ZC85. DOI: 10.7860/JCDR/2016/17592.7505.
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Posted June 12, 2018.
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- Hintzsche H, Stopper H. Micronucleus frequency in buccal mucosa cells of mobile phone users. Toxicology letters. 2010;193(1):124-130.
- Banerjee S, Singh NN, Sreedhar G, Mukherjee S. Analysis of the genotoxic effects of mobile phone radiation using buccal micronucleus assay: a comparative evaluation. Journal of clinical and diagnostic research: JCDR. 2016;10(3):ZC82.
- Holland N, Bolognesi C, Kirsch-Volders M, et al. The micronucleus assay in human buccal cells as a tool for biomonitoring DNA damage: the HUMN project perspective on current status and knowledge gaps. Mutation Research/Reviews in Mutation Research. 2008;659(1):93-108.