Study type: Medical/biological study (experimental study)

Linear relationship between flux density and tumor co-promoting effect of prolonged magnetic field exposure in a breast cancer model. med./bio.

Published in: Cancer Lett 1995; 96 (2): 175-180

Aim of study (acc. to author)

To investigate a possible relation between the magnetic flux density of a 50 Hz magnetic field and tumor growth in DMBA induced breast cancer in rats .

Background/further details

The chemical carcinogen DMBA (5 mg) was administered orally to induce mammary tumors. DMBA treatment was repeated in three consecutive weeks up to a total dose of 20 mg/per rat. Magnetic flux densities were 0.3-1 µT, 10 µT, 50 µT, and 100 µT. MF-exposure was conducted continuously for 91 days.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Modulation type: CW
Exposure duration: 24 h/day, 7 days/week, for 91 days
Exposure 2: 50 Hz
Modulation type: CW
Exposure duration: 24 h/day, 7 days/week, for 91 days
Exposure 3: 50 Hz
Modulation type: CW
Exposure duration: 24 h/day, 7 days/week, for 91 days
Exposure 4: 50 Hz
Modulation type: CW
Exposure duration: 24 h/day, 7 days/week, for 91 days

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Exposure duration 24 h/day, 7 days/week, for 91 days
Additional info gradient field horizontal
Modulation
Modulation type CW
Exposure setup
Exposure source
  • not specified
  • described earlier
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 1 µT effective value - - -
magnetic flux density 0.3 µT effective value - - -

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Exposure duration 24 h/day, 7 days/week, for 91 days
Additional info horizontal
Modulation
Modulation type CW
Exposure setup
Exposure source
  • not specified
  • described earlier
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 10 µT effective value - - -

Exposure 3

Main characteristics
Frequency 50 Hz
Type
Exposure duration 24 h/day, 7 days/week, for 91 days
Additional info horizontal
Modulation
Modulation type CW
Exposure setup
Exposure source
  • not specified
  • described earlier
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 50 µT effective value - - -

Exposure 4

Main characteristics
Frequency 50 Hz
Type
Exposure duration 24 h/day, 7 days/week, for 91 days
Additional info horizontal
Modulation
Modulation type CW
Exposure setup
Exposure source
  • not specified
  • described earlier
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 100 µT effective value - - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

No significant increase in incidence of mammary tumors were found at magnetic flux densities at 0.3-1 µT and 10 µT. However, a statistically significant increase in incidence of macroscopically visible tumors were found at 50 µT (25% about control) and 100 µT (50% about control. Linear regression analysis of the data revealed a linear relation between magnetic flux density and increase in tumor incidence.

Study character:

Study funded by

Related articles