Impact of Electromagnetic Exposures on Cellular Stresses

Coordinator for biology: Yves le Dréan

The next generation of wireless communication systems

• Due to the saturation of the lower part of the electromagnetic spectrum and the need of very high data rate transmissions (multimedia contents), the operating frequencies of emerging civil and professional wireless communication systems have recently shifted towards the millimeter wave frequency bands.
• Frequencies around 60 GHz are defined by the leading telecommunication companies as frequencies of the next generation wireless high-rate short-range digital networks.
  The figure shows applications of short-range millimetre waves, that will generate a new and permanent exposition for human population at 60 GHz.

Electromagnetic environment and human health.

Biological effects of electromagnetic waves could be divided into two categories:

1. Thermal effects of high-power radiation which are indirect effects due to high molecular vibrations
2. Non-thermal effects which are purely electromagnetic in nature
    
   The existing international standards and recommendations in telecommunications are only set in terms of thermal effects, and do not take into account potential non-thermal biological effects.  The informations concerning non-thermal bioelectromagnetic interactions so far available are quite poor and sometimes contradictory. However, recent studies have reported that non-thermal electromagnetic radiations may also interfere with some cellular processes. Therefore, the knowledge of the potential impacts of low-power millimetre waves on health is of utmost importance.
   
   
   

   Why focusing attention on frequency sub-bands around 60 GHz?

   • This band has been identified as highly promising for the next generation broadband Wireless Personal Area Networks
   • 60-GHz radiations are naturally absent from the environmental electromagnetic spectrum so that organisms have never been exposed to these radiations in normal conditions.
   • As the atmospheric attenuation at 60 GHz is caused by strong oxygen-induced absorption and as many molecular groups resonate around 60 GHz, it is crucial to verify if such kind of radiations could alter intracellular regulation processes by interfering with biosystems at the molecular level.
   • It is worth noting that low-intensity millimeter wave therapy has been already officially approved in a few Eastern European countries as an effective treatment method, suggesting that these radiations have potential effects on human bodies.
   
   
   

   Description of our project.

   • Our main goal is to determine the possible impacts of millimeter waves on various cellular stresses.
   • We have selected the human keratinocyte cell lines as the most appropriate model. The penetration depth of MMWs in biological tissues is up to a few millimeters (depending on frequency and tissues), indicating that the skin or near-surface zones of the tissues are the primary targets for MMW radiations.
   • Based on our preliminary experiments and on the literature, several biomarkers of stress have been selected for their high sensitivity to physico-chemical changes The effects of MMW on their gene expression will be studied by quantitative RT-PCR, which is the most sensitive and reliable method for analysing endogenous gene expression.
   • The role of the different radiation parameters (namely frequency, power density, modulation, polarization, exposure regimes), is under investigation.
   
   

   Objectives and expected results

   1. To determine if exposures to low-power millimeter waves artificially induced in our environment by emerging broadband wireless communication systems, might have deleterious effects on human health.
   2. Verification if low-power millimeter wave radiations might potentiate or alter the cellular response to other cellular insults such as oxidative or proteotoxic stresses.
   3. Contribution to the knowledge of the molecular and cellular mechanisms involved in bio-electromagnetism interactions. Our results will also provide key data about the potential use of low-power millimeter wave radiations for therapeutic and medical applications.
   4. To provide relevant and extensive scientific data for the future definition of international safety standards and recommendations regarding to the deployment of new communication systems in indoor and outdoor environments.
   5. Informations destined to the Standardization Committees and industry representatives about the specific radiation parameters (namely power level, operating frequency, modulation, polarization, and time regimes of exposure) with stressful actions at the cellular level. These data are of utmost importance and their dissemination will contribute to the reduction of direct or indirect heath risks potentially induced by wireless communication systems.

    

   Presentation of the partners

   This project benefits from the synergistic collaboration of two CNRS research units.  
   
   • Our group of “Homéostasie Intracellulaire des Protéines (HIP)” from the research unit UMR CNRS 6026 “Interactions Cellulaires et Moléculaires”.
   • The "Antenna & Microwave Department" from the "Institut d’Electronique et de Télécommunications de Rennes" (IETR). The expertise areas of this group extend from the EM modelling and design of innovating radiating structures to the experimental validations using a unique set of microwave and millimeter-wave platforms.