Medical/biological study (experimental study)

Cytogenetic studies in human blood lymphocytes exposed in vitro to radiofrequency radiation at a cellular telephone frequency (835.62 MHz, FDMA) med./bio.

By: Vijayalaxmi, Leal BZ, Meltz ML, Pickard WF, Bisht KS, Roti Roti JL, Straube WL, Moros EG

Published in: Radiat Res 2001; 155 (1): 113-121

Aim of study (acc. to editor)

Aim of the study was to investigate the extent of possible genetic damage caused by radiofrequency irradiation (835.62 MHz, 24 h, FDMA) on human blood lymphocytes in vitro.

Endpoint

genotoxicity/mutation: chromosomal aberration and micronuclei formation

Exposure

- FDMA
- CW continuous wave
- mobile communications

Exposure	Parameters
Exposure 1: 835.62 MHz Modulation type: CW Exposure duration: continuous for 24 h	power: 68 W (net forward power) power density: 860 W/m² (at the center of the flask) SAR: 4.4 W/kg mean SAR: 5 W/kg mean

Exposure 1

Main characteristics

Frequency	835.62 MHz
Type	electromagnetic field
Charakteristic	guided field
Exposure duration	continuous for 24 h

Modulation

Modulation type	CW
Additional info	FDMA/CW

Exposure setup

Exposure source	radial waveguide see details
Chamber	The facility housed nine RTLs (radial transmission lines) mounted on two separate adjacent sliding shelves. The facility and RTLs were shielded to avoid interference. Each RTL was formed by two parallel horizontal metal plates 4.3 cm apart, with a lightweight composite top plate hinged to the bottom aluminium plate (0.6 cm thick) providing mechanical support and homogeneity of the flasks' temperatures. The waves travelling from the central conical antenna were terminated by an annulus of MW-absorbing foam backed by perforated aluminium. The total radius was 53.3 cm.
Setup	Each RTL was fully loaded with 16 T-75 culture flasks at a radius of 29.2 cm each containing 40 ml of liquid medium (about 5 mm depth) (two of them diluted blood). The distance of the cells settled at the bottom of the flask from the antenna was between 24.7 cm and 33.8 cm.
Additional info	Aliquots of blood that were sham-exposed or exposed to 1.5 Gy of γ radiation were used as negative or positive controls.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power	68 W	-	-	-	net forward power
power density	860 W/m²	-	-	-	at the center of the flask
SAR	4.4 W/kg	mean	measured and calculated	-	-
SAR	5 W/kg	mean	measured and calculated	-	-

Measurement and calculation details

The SARs of flasks were measured by the temperature rise method using both a thermographic and a thermometric method. The experimental results were in reasonable agreement with those obtained from a three-dimensional FDTD numerical model analysis.

Reference articles

Moros EG et al. (1999): The radial transmission line as a broad-band shielded exposure system for microwave irradiation of large numbers of culture flasks

Exposed system:

human blood samples

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: formation of micronuclei; chromosomal aberration
cell viability/cell division/proliferation: mitotic index

Investigated system:

intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The overall cytogenetic responses of the lymphocytes were similar although the absolute values were slightly different. The mitotic indices, the indices of abnormal cells showing chromosomal damage, and the numbers of exchange aberrations were not significantly different between radiofrequency irradiation and sham-exposed cells. Similarly, the percentages of binucleated cells, the incidence of binucleated cells with one, two or three micronuclei, and the total numbers of micronuclei were not significantly different.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Air Force Office of Scientific Research (AFOSR), USA

Waldmann P et al. (2013): Influence of GSM Signals on Human Peripheral Lymphocytes: Study of Genotoxicity
Bourthoumieu S et al. (2010): Cytogenetic Studies in Human Cells Exposed In Vitro to GSM-900 MHz Radiofrequency Radiation Using R-Banded Karyotyping
Hansteen IL et al. (2009): Cytogenetic effects of 18.0 and 16.5 GHz microwave radiation on human lymphocytes in vitro
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
Juutilainen J et al. (2007): Micronucleus frequency in erythrocytes of mice after long-term exposure to radiofrequency radiation
Maes A et al. (2006): Cytogenetic investigation of subjects professionally exposed to radiofrequency radiation
Scarfi MR et al. (2006): Exposure to radiofrequency radiation (900 MHz, GSM signal) does not affect micronucleus frequency and cell proliferation in human peripheral blood lymphocytes: an interlaboratory study
Vijayalaxmi et al. (2001): Chromosome damage and micronucleus formation in human blood lymphocytes exposed in vitro to radiofrequency radiation at a cellular telephone frequency (847.74 MHz, CDMA)