Study type: Medical/biological study (experimental study)

Exposure to 60 Hz magnetic fields and risk of lymphoma in PIM transgenic and TSG-p53 (p53 knockout) mice. med./bio.

Published in: Carcinogenesis 1998; 19 (9): 1649-1653

Aim of study (acc. to author)

This in vivo study was performed to investigate the influence of 60 Hz magnetic fields on lymphoma induction in two strains of mice that are genetically predisposed to this disease.

Background/further details

Two transgenic mice model systems were used: 1.) pim-1 oncogene carrying mice (so called PIM transgenic mice, develop rapidly lymphoblastic lymphoma after a single dose of ethylnitrosourea) and 2.) mice which do not possess the tumor suppressor gene p53 (so called TSG-p53 mice).
Experiments were performed with 30 animals per sex and group to continuous and intermittent magnetic field exposure at different magnetic flux densities.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 60 Hz
Exposure duration: 18.5 h/day for 23 weeks
Exposure 2: 60 Hz
Exposure duration: 1 h on - 1 h off for 18.5 h/day for 23 weeks

Exposure 1

Main characteristics
Frequency 60 Hz
Type
Polarization
Exposure duration 18.5 h/day for 23 weeks
Exposure setup
Exposure source
  • not specified
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 1 mT maximum measured - -
magnetic flux density 0.2 mT - measured - -
magnetic flux density 0.002 mT minimum measured - -

Exposure 2

Main characteristics
Frequency 60 Hz
Type
Polarization
Exposure duration 1 h on - 1 h off for 18.5 h/day for 23 weeks
Exposure setup
Exposure source
  • not specified
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 1 mT - measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The lymphoma incidence in male PIM mice exposed continuously to 10 G magnetic fields was significantly reduced from that seen in sex-matched sham exposure. No significant difference in the lymphoma incidence was observed between the sham exposure and the other exposure groups in both mice strains.
These results do not support the hypothesis that the exposure to magnetic fields is a significant risk factor for lymphoid neoplasia in mice with a genetic predisposition to this disease.

Study character:

Study funded by

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