Study type: Medical/biological study (experimental study)

The Cytome Assay as a Tool to Investigate the Possible Association Between Exposure to Extremely Low Frequency Magnetic Fields and an Increased Risk for Alzheimer's Disease med./bio.

Published in: J Alzheimers Dis 2015; 50 (3): 741-749

Aim of study (acc. to author)

The genotoxic effects of exposure of human liver carcinoma cells to a 50 Hz magnetic field should be investigated in view of similarities to charactersitics of Alzheimer's disease patients cells.

Background/further details

The study comprised two parts. In the first part, cells were exposed to 10, 50, 100 and 500 µT magnetic fields. The second part was conducted as an independent repetition experiment with slightly changed exposure values, namely 5, 10, 50 and 100 µT. Each exposure was accompanied by its own unexposed control group and by a positive control (15 µg/ml methyl methane sulfonate).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 24 hours
Exposure 2: 50 Hz
Exposure duration: continuous for 24 hours
Exposure 3: 50 Hz
Exposure duration: continuous for 24 hours
Exposure 4: 50 Hz
Exposure duration: continuous for 24 hours
Exposure 5: 50 Hz
Exposure duration: continuous for 24 hours

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Additional info the field was not perfectly sinusoidal and contained 50 Hz fields (100%) as well as harmonics (10% at 250 Hz and 350 Hz and 5% at 550 Hz and 650 Hz)
Exposure setup
Exposure source
Chamber 24 well plates in incubator
Setup a cylindrical coil (380 turn coil, 42 cm long, 20 cm inner diameter) with dimensions that were chosen so that it could be placed inside the incubator and provide a sufficiently large zone in which the cultures could be exposed to a nearly constant magnetic field (with a tolerance of a few percent)
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 µT - calculated - -

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 10 µT - calculated - -

Exposure 3

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 50 µT - calculated - -

Exposure 4

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 100 µT - calculated - -

Exposure 5

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hours
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 500 µT - calculated - -

Reference articles

  • Verheyen GR et al. (2003): Effect of coexposure to 50 Hz magnetic fields and an aneugen on human lymphocytes, determined by the cytokinesis block micronucleus assay
  • Maes A et al. (2000): Cytogenetic effects of 50 Hz magnetic fields of different magnetic flux densities

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The analysis of both experiments showed that micronuclei and nuclear buds were significantly increased in cells exposed to magnetic flux densities of ≥50 µT and that nuclear bridges were significantly increased in cells exposed to magnetic flux densities of ≥100 µT compared to the control groups.
Cells with micronuclei predominantly contained large micronuclei presuming aneuploidy rather than chromosome breakage.
No cytotoxicity or apoptosis was found in any group. Necrosis and centrosome abnormalities were not scored as they were almost never seen.
The authors conclude that exposure of human liver carcinoma cells to a 50 Hz magnetic field with magnetic flux densities above 50 µT may induce chromosome instabilities as those found in Alzheimer's disease patients cells.

Study character:

Study funded by

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