EMF-Portal | Primary DNA damage in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation

[Primärer DNA-Schaden in menschlichen Blut-Lymphozyten, die in vitro bei 2450 MHz Hochfrequenz-Befeldung exponiert wurden]

Ziel der Studie (lt. Redakteur)

Endpunkt

Exposition/Befeldung (teilweise nur auf Englisch)

2,45 GHz

Exposition	Parameter
Exposition 1: 2,45 GHz Modulationsart: gepulst Expositionsdauer: kontinuierlich für 2 h	Leistung: 21 W (net forward power) Leistungsflussdichte: 5 mW/cm² Mittelwert (±7%) SAR: 2,135 W/kg Mittelwert (± 0,005 W/kg) SAR: 5,015 W/kg Maximum (see add. information)

Exposition 1

Hauptcharakteristika

Frequenz	2,45 GHz
Typ	elektromagnetisches Feld
Charakteristik	Nahfeld
Expositionsdauer	kontinuierlich für 2 h

Modulation

Modulationsart	gepulst
Pulsbreite	10 µs
Tastgrad	10 %
Folgefrequenz	10 kHz

Expositionsaufbau

Expositionsquelle	Hornantenne abgeschirmter Raum 35.5 x 25.5 cm, in a vertically downward direction
Abstand zw. exponiertem Objekt und Expositionsquelle	1,75 m
Kammer	The anechoic room of 5.2 x 3.35 x 3.35 m was maintained at 22 ± 1°C. A Plexiglas (0.6-cm thick) box with two compartments and outside dimensions of 24.5 x 21.0 x 3.7 cm was placed in a tightly fitting pressed-foam box of 27 x 22 x 7 cm which was positioned directly under the horn antenna.
Aufbau	Four T-25 tissue culture flasks were positioned in the open upper compartment of 1.2 cm height, three of them containing 6 ml of whole blood, the fourth one being used for temperature monitoring. The compartment was filled with warm water up to the height of the medium in the flasks. The closed lower compartment was circulated with warm water to maintain the liquid in the flasks at 37°C.
Schein-Exposition	Eine Schein-Exposition wurde durchgeführt.
Zusatzinfo	The pressed-foam box for simultaneous sham exposure was placed at the far end of the anechoic room away from the horn. Control samples were incubated for 2 h minus 5 min and in the end exposed to 50 cGy of ionizing radiation from a ¹³⁷Cs γ-ray source at a dose rate of 1.008 cGy/min.

Parameter

Messgröße	Wert	Typ	Methode	Masse	Bemerkungen
Leistung	21 W	-	-	-	net forward power
Leistungsflussdichte	5 mW/cm²	Mittelwert	gemessen	-	±7%
SAR	2,135 W/kg	Mittelwert	berechnet	-	± 0,005 W/kg
SAR	5,015 W/kg	Maximum	berechnet	-	see add. information

Zusätzliche Parameterdetails

The SAR was calculated using FDTD analysis. The values varied from 8.175 x 10^-5 to 5.015 W/kg at different cell positions in the flasks. 90, 75, 50, 25, and 10% of the cells were exposed to SARs greater than 0.950, 1.395, 2.080, 2.730, and 3.520 W/kg, respectively.

Mess- und Berechnungsdetails

The power density in the center of the field at the location intended for exposure of the cells was measured using a calibrated electromagnetic radiation monitor and probe. The variation at the four flask positions was ±7%.

Referenzartikel

Vijayalaxmi et al. (1997): Proliferation and cytogenetic studies in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation

Methoden Endpunkt/Messparameter/Methodik

Genotoxizität/Mutation: primäre DNA-Schäden (Einzelstrangbrüche und alkalilabile Läsionen; alkalischer Comet-Assay (Schweif-Länge, Schweif-Intensität, Schweif-Moment (Schweif-Länge x Schweif-Intensität oder Prozent gewanderte DNA)))

Untersuchtes System:

intakte Zelle/Zellkultur (in vitro)

Untersuchungszeitpunkt:

nach der Befeldung

Hauptergebnis der Studie (lt. Autor)

Studienmerkmale:

medizinische/biologische Studie
experimentelle Studie
Voll-/Hauptstudie

Studie gefördert durch

Air Force Office of Scientific Research (AFOSR), USA

Themenverwandte Artikel

Koyama S et al. (2007): Effects of 2.45 GHz electromagnetic fields with a wide range of SARs on bacterial and HPRT gene mutations

Vijayalaxmi (2006): Cytogenetic studies in human blood lymphocytes exposed in vitro to 2.45 GHz or 8.2 GHz radiofrequency radiation

Primary DNA damage in human blood lymphocytes exposed in vitro to 2450 MHz radiofrequency radiation med./bio.