Study type: Medical/biological study (experimental study)

Mobile phone base station radiation does not affect neoplastic transformation in BALB/3T3 cells med./bio.

By: Hirose H, Suhara T, Kaji N, Sakuma N, Sekijima M, Nojima T, Miyakoshi J
Published in: Bioelectromagnetics 2008; 29 (1): 55-64
Download citation in RIS format

Aim of study (acc. to author)

To study whether exposure to 2.1425 GHz W-CDMA radiofrequency electromagnetic fields induces neoplastic transformation at the exposure limit value of the average whole-body SAR levels based on ICNIRP guidelines.

Background/further details

Mouse embryonic fibroblasts (BALB/3T3 cells) were continuously exposed to radiofrequency electromagnetic fields at specific absorption rates of 80 and 800 mW/kg for 6 weeks. In addition, 3-methylcholanthrene (MCA)-treated cells were exposed in a similar fashion to assess the effects on tumor promotion. Finally, the effect of radiofrequency electromagnetic fields on tumor co-promotion was assessed in cells initiated with MCA and co-exposed to TPA.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.1425 GHz
Exposure duration: continuous for 6 weeks

Exposure 1

Main characteristics
Frequency 2.1425 GHz
Type
Exposure duration continuous for 6 weeks
Modulation
Modulation type cf. additional info
Additional info

The W-CDMA component of the IMT-2000 cellular system adopts Direct Sequence CDMA (DS-CDMA) and Frequency Division Duplex (FDD) as a multiple access and duplex scheme. The chip rate of the spread code is 3.84 megachip per second (Mcps).
Exposure setup
Exposure source
Chamber Two identical RF field exposure incubators, consisting of a horn antenna and a dielectric lens for beam forming and a culture case, were placed in separate anechoic chambers, and a mechanical switch in a dummy box was used to select RF or sham exposure.
Setup This system allowed simultaneous exposure of 49 (7 x 7 array) 35-mm culture dishes with a similar SAR uniformity within each dish [Iyama et al., 2004].
Sham exposure A sham exposure was conducted.
Additional info Identical air at 37 °C, 5% CO2, and >90% humidity was provided to the two culture units through sealed ducts.
Parameters
Measurand Value Type Method Mass Remarks
SAR 80 mW/kg mean - - ±59%
SAR 800 mW/kg mean - - ±59%
Additional parameter details

The mean SAR of the culture fluid at the bottom of the 49 culture dishes was 175 mW/kg for an antenna input power of 1 W, and the standard deviation of the SAR distribution was 59%.

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

No significant differences in transformation frequency were found between the test groups exposed to radiofrequency electromagnetic fields and the sham exposed controls in the non-, MCA-, or "MCA plus TPA"-treated cells.
The data provided no evidence to support the hypothesis that radiofrequency electromagnetic fields may affect malignant transformation. Thus, the results suggest that exposure to low-level radiofrequency irradiation of up to 800 mW/kg does not induce cell transformation, which causes tumor formation.

Study character:

Study funded by

Related articles