ID Number		2031
Study Type		In Vivo
Model		900, 1800 MHz (CW) exposure to rats and analysis if blood brain barrier permeability
Details		Wistar rats were exposed to 900 and 1800 MHz (CW) for 20 minutes at field strengths of 13.51 +/- 0.41 and 12.62 +/- 0.22 V/m, respectively (no SAR). The authors report increased permeability in male but not female rats. AUTHORS' ABSTRACT: Sirav and Seyhan 2011 (IEEE #6106): During the last several decades, numerous studies have been performed aiming at the question of whether or not exposure to radiofrequency radiation (RFR) influences the permeability of the blood-brain barrier (BBB). The objective of this study was to investigate the effect of RFR on the permeability of BBB in male and female Wistar albino rats. Right brain, left brain, cerebellum, and total brain were analyzed separately in the study. Rats were exposed to 0.9 and 1.8 GHz continuous-wave (CW) RFR for 20 min (at SARs of 4.26 mW/kg and 1.46 mW/kg, respectively) while under anesthesia. Control rats were sham-exposed. Disruption of BBB integrity was detected spectrophotometrically using the Evans-blue dye, which has been used as a BBB tracer and is known to be bound to serum albumin. Right brain, left brain, cerebellum, and total brain were evaluated for BBB permeability. In female rats, no albumin extravasation was found in in the brain after RFR exposure. A significant increase in albumin was found in the brains of the RF-exposed male rats when compared to sham-exposed male brains. These results suggest that exposure to 0.9 and 1.8 GHz CW RFR at levels below the international limits can affect the vascular permeability in the brain of male rats. The possible risk of RFR exposure in humans is a major concern for the society. Thus, this topic should be investigated more thoroughly in the future. AUTHORS' ABSTRACT: Seyhan et al. 2011 (IEEE #6107): The effects of Radiofrequency Radiation (RFR) in the frequencies of mobile phones (835, 900, 1800 MHz) on the permeability of blood-brain barrier and hydroxyproline formation along with the modeling studies performed at the Gazi Biophysics Laboratory are reviewed in this paper. The close proximity of a mobile phone to a users head leads to absorption of part of the mobile phone emitted energy by the head and the brain of the phone user. Permeability of the blood-brain barrier (BBB) of female and male rat brain tissues was examined under 900MHz and 1800MHz continuous-wave radiofrequency radiation (CWRFR) exposure. Increase in BBB permeability was found to be statistically significant in all male rats exposed, whereas no significant difference was observed in female rats. Investigations of the mobile phone radiation effects on biomolecules were also carried out with guinea pigs. Alterations in protein synthesis were quantified by measuring hydroxyproline level in exposed and non-exposed liver tissues by using three different biochemical methods. There was no significant difference on hepatic hydroxyproline levels of RFR exposed guinea pig. In a simulation study, the effects of 835 MHz and 900 MHz RFR exposures on human head while using cellular phone (CP) were investigated. The effects of CP usage on specific absorption rate (SAR) were calculated by SEMCAD X software which uses FDTD method in details. Some parameters as the different head dimensions and dielectric properties of the head (adult and child), positions of the mobile phone (cheek and tilt), and rectangular metal frame spectacles as a widely used metallic accessory were considered. With this aim, dose values in the tissue for 10 g peak spatial-average SAR value were calculated. At both of the frequencies of 835 MHz and 900 MHz, higher SAR values were obtained in the cheek positions than the tilt positions for conditions of with or without metal frame spectacles.
Findings		Effects
Status		Completed With Publication
Principal Investigator		Gazi University, Ankara, Turkey
Funding Agency		Private/Instit.
Country		TURKEY
References		Sirav, B et al. Electromagn Biol Med, (2009) 28:215-222 Sirav, B et al. Electromagn Biol Med., (2011) 30:253-260 Seyhan, N et al. Eur. J. Oncol. Library. (http://www.icems.eu/papers/ramazzini_library5_part2.pdf), (2011) 5:319-332
Comments