Medizinische/biologische Studie (experimentelle Studie)

Effects of modulated microwave radiation at cellular telephone frequency (1.95 GHz) on X-ray-induced chromosome aberrations in human lymphocytes in vitro med./bio.

[Wikungen modulierter Mikrowellen-Befeldung bei Mobiltelefon-Frequenz (1,95 GHz) auf Röntgenstrahl-induzierte Chromosomen-Aberrationen bei menschlichen Lymphozyten in vitro]

Von: Manti L, Braselmann H, Calabrese ML, Massa R, Pugliese M, Scampoli P, Sicignano G, Grossi G

Veröffentlicht in: Radiat Res 2008; 169 (5): 575-583

Ziel der Studie (lt. Autor)

Diese in vitro-Studie wurde durchgeführt, um Wirkungen modulierter 1,95 GHz-UMTS-Hochfrequenz-Exposition auf Röntgenstrahlen-induzierte Chromosomenaberrationen bei menschlichen Lymphozyten zu untersuchen.

Hintergrund/weitere Details

Die Lymphozyten wurden von vier gesunden Männern im Alter von 23 bis 30 Jahren gewonnen.

Endpunkt

Genotoxizität/Mutation: Chromosomenaberrationen

Exposition/Befeldung (teilweise nur auf Englisch)

- CDMA
- Mobilfunk
- digitales Mobiltelefon
- UMTS

Exposition	Parameter
Exposition 1: 1,95 GHz Expositionsdauer: kontinuierlich für 24 h	SAR: 2 W/kg Mittelwert SAR: 0,5 W/kg Mittelwert

Exposition 1

Hauptcharakteristika

Frequenz	1,95 GHz
Typ	elektromagnetisches Feld
Charakteristik	gerichtetes Feld
Expositionsdauer	kontinuierlich für 24 h

Modulation

Modulationsart	s. Zusatzinfo
Zusatzinfo	UMTS signal meeting the WCDMA standard, according to the 3GPP 3.5 2001-03 specifications (five power-controlled user data channels and one control channel)

Expositionsaufbau

Expositionsquelle	Wellenleiter WR 430, rectangular, 109.2 mm x 54.6 mm
Kammer	The standardized exposure device has been described in [Sannino et al., 2006 and Calabrese et al., 2006]. Two identical waveguides, one for RF and one for sham exposure, were housed in a commercial incubator at 37°C with 95% air and 5% CO₂.
Aufbau	A total of eight 35-mm Petri dishes were inoculated with lymphocytes from each donor. Four dishes, each filled with 3 ml of cell suspension, were held by a plastic stand in each waveguide. The distance between the samples allowed simultaneous exposure at two different SARs. The induced electric field was essentially parallel to the sample surface.
Schein-Exposition	Eine Schein-Exposition wurde durchgeführt.
Zusatzinfo	The feeding end was a coaxial waveguide adapter, the other end terminated with a fixed short circuit. The center of the samples was at a distance of 0.5 λ from the short circuit in order to achieve the best trade-off between efficiency and SAR uniformity.

Parameter

Messgröße	Wert	Typ	Methode	Masse	Bemerkungen
SAR	2 W/kg	Mittelwert	bestimmt über Leistungsverlust	-	-
SAR	0,5 W/kg	Mittelwert	bestimmt über Leistungsverlust	-	-

Zusätzliche Parameterdetails

Two of the dishes in each waveguide were given 4 Gy of X rays immediately before RF or sham exposure (one dish per SAR). The X rays were produced by a Thomson tube (250 kVp, 0.8 Gy/min) and filtered by 1-mm thick copper foil.

Mess- und Berechnungsdetails

Incident and reflected powers were measured using a bidirectional power sensor connected to a computer continuously adjusting the power level of the signal generator to the required SAR. Measurements of local SAR and power efficiency showed good agreement with the calculated values. The ratio between the SAR standard deviation and the average SAR was 0.33 in all four samples. The measured increase in temperature during the RF exposure at 2 W/kg was 0.2 ± 0.1°C, which was considered sufficiently low to exclude damage induced by thermal processes.

Referenzartikel

Sannino A et al. (2006): Evaluation of Cytotoxic and Genotoxic Effects in Human Peripheral Blood Leukocytes Following Exposure to 1950-MHz Modulated Signal
Calabrese M et al. (2006): A high-efficiency waveguide applicator for in vitro exposure of mammalian cells at 1.95 GHz

Exponiertes System:

intakte Zelle/Zellkultur (in vitro)

Methoden Endpunkt/Messparameter/Methodik

Genotoxizität/Mutation: Chromosomenaberrationen (z.B. symmetrische und asymmetrische Chromosomen-Austausche, azentrische Fragmente; Anteil anomaler Zellen, Häufigkeit der gesamten Chromosomen-Austausche pro Zelle): Fluoreszenz-In-Situ-Hybridisierung

Untersuchtes System:

DNA/RNA (in vitro)
Chromosom 1 und 2

Untersuchungszeitpunkt:

nach der Befeldung

Hauptergebnis der Studie (lt. Autor)

Die UMTS-Exposition führte zu keinen signifikanten Veränderungen im Anteil der Röntgenstrahlung-induzierten anormalen Zellen. Allerdings wurde ein leichter, aber signifikanter Anstieg in der Häufigkeit der Röntgenstrahlung-induzierten Chromosomen-Austausche pro Zelle, besonders bei einer spezifischen Absorptionsrate von 2 W/kg, beobachtet.
Zusammengefasst verschlechtert die Exposition bei einem 1,95 GHz-UMTS-modulierten Hochfrequenz-Feld nicht die durch ionisierende Strahlung induzierte Menge an anormalen Zellen, könnte aber das Gesamtausmaß des Röntgenstrahlung-induzierten Chromosomen-Schadens pro Zelle bei Lymphozyten in der ersten Mitose bei einer spezifischen Absorptionsrate von 2 W/kg steigern.

Studienmerkmale:

medizinische/biologische Studie
experimentelle Studie
Voll-/Hauptstudie
Blindstudie

Studie gefördert durch

Centre of Competence on Information and Communication Technologies, Regione Campania, Italy
Project "Wireless Technology Health Risks", Italy

Themenverwandte Artikel

Zeni O et al. (2012): Radiofrequency radiation at 1950 MHz (UMTS) does not affect key cellular endpoints in neuron-like PC12 cells
Bourthoumieu S et al. (2010): Cytogenetic Studies in Human Cells Exposed In Vitro to GSM-900 MHz Radiofrequency Radiation Using R-Banded Karyotyping
Schwarz C et al. (2008): Radiofrequency electromagnetic fields (UMTS, 1,950 MHz) induce genotoxic effects in vitro in human fibroblasts but not in lymphocytes
Zeni O et al. (2008): Evaluation of genotoxic effects in human leukocytes after in vitro exposure to 1950 MHz UMTS radiofrequency field
Tiwari R et al. (2008): Combinative Exposure Effect of Radio Frequency Signals from CDMA Mobile Phones and Aphidicolin on DNA Integrity
Baohong W et al. (2007): Evaluating the combinative effects on human lymphocyte DNA damage induced by ultraviolet ray C plus 1.8 GHz microwaves using comet assay in vitro
Tuschl H et al. (2006): In vitro effects of GSM modulated radiofrequency fields on human immune cells
Maes A et al. (2006): Cytogenetic investigation of subjects professionally exposed to radiofrequency radiation
Baohong W et al. (2005): Studying the synergistic damage effects induced by 1.8 GHz radiofrequency field radiation (RFR) with four chemical mutagens on human lymphocyte DNA using comet assay in vitro
Lalic H et al. (2001): Comparison of chromosome aberrations in peripheral blood lymphocytes from people occupationally exposed to ionizing and radiofrequency radiation
Garson OM et al. (1991): A chromosomal study of workers with long-term exposure to radio-frequency radiation
Garaj-Vrhovac V et al. (1990): Comparison of chromosome aberration and micronucleus induction in human lymphocytes after occupational exposure to vinyl chloride monomer and microwave radiation