This study demonstrates that exposure to 900 MHz GSM mobile phone radiation and 2.4 GHz radio frequency radiation emitted from common Wi-Fi routers made Listeria monocytogenes and Escherichia coli resistant to different antibiotics. These findings naturally have direct implications for the management of serious infectious diseases. With the escalating development into antibiotics-resistant microorganisms around the world, this adaptive phenomenon and its potential threats to human health requires further urgent investigation.
Evaluation of the Effect of Radiofrequency Radiation Emitted From Wi-Fi Router and Mobile Phone Simulator on the Antibacterial Susceptibility of Pathogenic Bacteria Listeria monocytogenes and Escherichia coli
Dose Response. 2017 Jan-Mar
M. Taheri; S. M. J. Mortazavi; M. Moradi; S. Mansouri; G. R. Hatam and F. Nouri
Mobile phones and Wi-Fi radiofrequency radiation are among the main sources of the exposure of the general population to radiofrequency electromagnetic fields (RF-EMF). Previous studies have shown that exposure of microorganisms to RF-EMFs can be associated with a wide spectrum of changes ranged from the modified bacterial growth to the alterations of the pattern of antibiotic resistance. Our laboratory at the nonionizing department of the Ionizing and Non-ionizing Radiation Protection Research Center has performed experiments on the health effects of exposure to animal models and humans to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons, magnetic resonance imaging, and Helmholtz coils. On the other hand, we have previously studied different aspects of the challenging issue of the ionizing or nonionizing radiation-induced alterations in the susceptibility of microorganisms to antibiotics.
In this study, we assessed if the exposure to 900 MHz GSM mobile phone radiation and 2.4 GHz radiofrequency radiation emitted from common Wi-Fi routers alters the susceptibility of microorganisms to different antibiotics. The pure cultures of Listeria monocytogenes and Escherichia coli were exposed to RF-EMFs generated either by a GSM 900 MHz mobile phone simulator and a common 2.4 GHz Wi-Fi router. It is also shown that exposure to RF-EMFs within a narrow level of irradiation (an exposure window) makes microorganisms resistant to antibiotics. This adaptive phenomenon and its potential threats to human health should be further investigated in future experiments. Altogether, the findings of this study showed that exposure to Wi-Fi and RF simulator radiation can significantly alter the inhibition zone diameters and growth rate for L monocytogenes and E coli. These findings may have implications for the management of serious infectious diseases.
Based on our results, it can be concluded that the bacterial strains used in this study respond differently to EMFs. These bacteria were capable of responding to environmental stresses that act by activating some specific systems such as ion channels, change via the membrane, DNA repair system, and probably ion efflux pumps in the membrane as well as interactions of molecules and antibacterial agents.61 There are some ambiguities that need further investigations regarding answering questions such as which cellular mechanism is responsible for adaptation? Which factors are involved in alterations of antibacterial sensitivity? And subsequently, what are the differences in the response to radiation in gram-negative and gram-positive bacteria? Moreover, experiments on different bacterial strains with various electromagnetic fields should be performed in the future to better clarify these uncertainties.