Medical/biological study (experimental study)

The influence of 1.2 microT, 60 Hz magnetic fields on melatonin- and tamoxifen-induced inhibition of MCF-7 cell growth.

Published in: Bioelectromagnetics 2001; 22 (2): 122-128

Aim of study (acc. to author)

To replicate the study of Harland and Liburdy (1997), in which the exposure to 60 Hz magnetic fields could significantly reduce the inhibitory action of melatonin and tamoxifen on the growth of MCF-7 human breast cancer cells in vitro.
Background/further details: In the melatonin study, nine cell samples were subdivided in the following groups and investigated on day 7: 1.) control group, 2.) melatonin group (10 -9 M), and 3.) melatonin + exposure group.
In the tamoxifen study, 48 cell samples were subdivided in the following groups: 1.) control group, 2.) tamoxifen group (10 -7 M), and 3.) tamoxifen + exposure group. The samples were investigated on days 4, 5, 6, and 7.



Exposure Parameters
Exposure 1: 60 Hz
Exposure duration: continuous, up to 7 days
Exposure 1
Main characteristics
Frequency 60 Hz
Exposure duration continuous, up to 7 days
Exposure setup
Exposure source
Chamber CO2 incubator, 35 mm dishes
Setup coils with 1000 turns, 20 cm diameter, 10 cm apart, vertical field; culture dishes in uniform field region
Sham exposure A sham exposure was conducted.
Measurand Value Type Method Mass Remarks
magnetic flux density 1.2 µT effective value measured - -
Additional parameter details
ambient fields: 0.04 µT rms; static magnetic field < 0.3 µT
Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated material:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

In the melatonin study, cell numbers were significantly reduced (by 16.7%) in the melatonin treated cultures after 7 days of incubation compared to control cultures, whereas the melatonin treated and exposed cultures had the same cell populations as the control cultures. In the tamoxifen study, tamoxifen reduced the cell growth by 18.6% and 25% on days 6 and 7, respectively, compared to the control group, while the cell growth in the tamoxifen treated and exposed cell cultures was reduced only by 8.7% and 13.1%, respectively.
The authors conclude that these results are consistent with those reported by Harland and Liburdy (1997).
Study character:

Study funded by

  • Department of Energy, USA

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