Medical/biological study (experimental study)

Indication of cocarcinogenic potential of chronic UMTS-modulated radiofrequency exposure in an ethylnitrosourea mouse model.

Published in: Int J Radiat Biol 2010; 86 (7): 529-541

Aim of study (acc. to author)

To study the tumour susceptibility in mice exposed to a UMTS signal for up to 24 months commencing with embryo-fetal exposure.
Background/further details: Animals were exposed to UMTS electromagnetic fields with different intensities (4.8 and 48 W/m²) and the low-dose group (4.8 W/m²) was additionally subjected to prenatal ethylnitrosourea treatment (40 mg ENU/kg body weight).
In total, five treatment groups were used: Two exposure groups, sham exposure group, cage control group and positive control group (ENU treatment only). Exposure and sham exposure of the maternal mice started on day 6 post conception, while the maternal ENU treatment was carried out on day 14 post conception. Each treatment group consisted originally of up to 20 maternal mice and their litters. After the first week of lifetime, litter standardisation was performed and afterwards three female offspring per cage and their mothers were maintained up to the weaning time point. After weaning, maternal mice were removed from the cages and the study was conducted using the three remaining female offspring (thus about 60 mice per group).
Different pre-studies were also performed (e.g. concerning thermoregulation or ENU mortality of a different mouse strain).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1,966 MHz
Exposure duration: continuous for 20 hr/day, 7 days/week for up to 24 months
  • power density density: 4.8 W/m² average over time (deck with low exposure)
  • power density density: 48 W/m² average over time (deck with high exposure)
  • SAR: 0.62 W/kg average over mass (3 pups (3 g, together with the dam))
  • SAR: 1.19 W/kg average over mass (3 old females (55 g))
  • SAR: 3.84 W/kg average over mass (1 mature female (30 g))
  • SAR: 4.48 W/kg average over mass (1 mature female (30 g, together with 3 pups))
  • SAR: 5.76 W/kg average over mass (3 young females (12.5 g))
General information
animals were treated in five groups: i) cage control - no treatment ii) ENU control 40 mg ENU per kg body weight iii) sham exposure iv) UMTS exposure to 4.8 W/m² + 40 mg ENU per kg body weight v) UMTS exposure to 48 W/m²
Exposure 1
Main characteristics
Frequency 1,966 MHz
Type
Exposure duration continuous for 20 hr/day, 7 days/week for up to 24 months
Exposure setup
Exposure source/structure
Chamber details exposure performed in a three decker exposure device (sham, low and high exposure; see exposure parameters)
Setup details test signal delivered by a generic UMTS signal generator and amplified with a power amplifier
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Remarks
power density density 4.8 W/m² average over time - deck with low exposure
power density density 48 W/m² average over time - deck with high exposure
SAR 0.62 W/kg average over mass calculated 3 pups (3 g, together with the dam)
SAR 1.19 W/kg average over mass calculated 3 old females (55 g)
SAR 3.84 W/kg average over mass calculated 1 mature female (30 g)
SAR 4.48 W/kg average over mass calculated 1 mature female (30 g, together with 3 pups)
SAR 5.76 W/kg average over mass calculated 3 young females (12.5 g)
Exposed system:
  • animal: mouse/B6C3F1
  • whole body

Methods Endpoint/measurement parameters/methodology

Investigated material:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

The high-level UMTS exposure (48 W/m²), the sham exposure, and the cage control groups showed comparable tumour incidences in the organs. In contrast, the ENU-treated and UMTS-co-exposed (at 4.8 W/m²) animals displayed an enhanced lung tumour rate and an increased incidence of lung carcinomas as compared to the controls treated with ENU only. Furthermore, tumour multiplicity of the lung carcinomas was increased and the number of metastasising lung tumours was doubled in the ENU/UMTS co-exposure group as compared to the ENU control group.
The authors conclude that this pilot study indicates a cocarcinogenic effect of lifelong UMTS exposure (4.8 W/m²) in female B6C3F1 offspring subjected to pretreatment with ethylnitrosourea.
Study character:
  • medical/biological study
  • experimental study
  • pilot/exploratory/preliminary study

Study funded by

  • Compagnia di San Paolo, Torino, Italy

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