Medical/biological study (experimental study)

Intermittent extremely low frequency electromagnetic fields cause DNA damage in a dose-dependent way. med./bio.

By: Ivancsits S, Diem E, Jahn O, Rudiger HW

Published in: Int Arch Occup Environ Health 2003; 76 (6): 431-436

Aim of study (acc. to author)

To study the influence of exposure time and magnetic flux densities on the induction of DNA strand breaks with human fibroblast cultures of three healthy donors.

Background/further details

In a previous study (publication 9089) the authors demonstrated an increase in DNA single-strand breaks in human fibroblasts upon intermittent exposure to a 50 Hz magnetic field. The extent of electromagnetic field-induced DNA damage was variable in relation to the setting of on and off times, and was highest at an intermittence of "5 min on/10 min off".

Endpoint

genotoxicity/mutation: DNA damage (DNA single-strand breaks/double-strand breaks)

Exposure

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: intermittent, 5 min on/10 min off, for 1-24 h	magnetic flux density: 20 µT minimum magnetic flux density: 1 mT maximum

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	intermittent, 5 min on/10 min off, for 1-24 h

Exposure setup

Exposure source	2 four coil systems each of which placed inside a µ-metal box
Chamber	Exposure chamber placed inside a commercial incubator.
Setup	35 mm Petri dishes placed inside the µ-box.
Sham exposure	A sham exposure was conducted.
Additional info	The currents in the bi-filar coils were switched parallel for field exposure or non-parallel for sham exposure.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	20 µT	minimum	unspecified	-	-
magnetic flux density	1 mT	maximum	unspecified	-	-

Additional parameter details

Geomagnetic field in the exposure chamber was 20 to 50 µT.

Exposed system:

intact cell/cell culture
human fibroblasts

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: DNA damage (DNA single-strand breaks/double-strand breaks (alkaline and neutral comet assay, "comet tail factor"))

Investigated material:

DNA/RNA

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Extremely low frequency electromagnetic field exposure induced dose-dependent and time-dependent DNA single-strand breaks and double-strand breaks. Effects occurred at a magnetic flux density as low as 35 µT, being well below proposed International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. After termination of irradiation the induced "comet tail factors" returned to normal within 9 h.
The induced DNA damage is not based on thermal effects and arouses concern about environmental threshold limit values for extremely low frequency electromagnetic field exposure.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

European Union (EU)/European Commission

Sun C et al. (2018): Ataxia telangiectasia mutated deficiency does not result in genetic susceptibility to 50 Hz magnetic fields exposure in mouse embryonic fibroblasts.
Nakayama M et al. (2016): Evaluation of cell viability, DNA single-strand breaks, and nitric oxide production in LPS-stimulated macrophage RAW264 exposed to a 50-Hz magnetic field.
Zhu K et al. (2016): Extremely low frequency magnetic fields do not induce DNA damage in human lens epithelial cells in vitro.
Duan W et al. (2015): Comparison of the genotoxic effects induced by 50 Hz extremely low-frequency electromagnetic fields and 1800 MHz radiofrequency electromagnetic fields in GC-2 cells.
Nakayama M et al. (2014): DNA Strand Breaks in Fibroblasts Exposed to a 50-Hz Magnetic Field.
Yoon HE et al. (2014): Increased gamma-H2AX by exposure to a 60-Hz magnetic fields combined with ionizing radiation, but not hydrogen peroxide, in non-tumorigenic human cell lines.
Focke F et al. (2010): DNA fragmentation in human fibroblasts under extremely low frequency electromagnetic field exposure.
Burdak-Rothkamm S et al. (2009): DNA and chromosomal damage in response to intermittent extremely low-frequency magnetic fields.
Yokus B et al. (2008): Extremely low frequency magnetic fields cause oxidative DNA damage in rats.
Wahab MA et al. (2007): Elevated sister chromatid exchange frequencies in dividing human peripheral blood lymphocytes exposed to 50 Hz magnetic fields.
Mairs RJ et al. (2007): Microsatellite analysis for determination of the mutagenicity of extremely low-frequency electromagnetic fields and ionising radiation in vitro.
Villarini M et al. (2006): Effects of co-exposure to extremely low frequency (50 Hz) magnetic fields and xenobiotics determined in vitro by the alkaline comet assay.
Udroiu I et al. (2006): Clastogenicity and aneuploidy in newborn and adult mice exposed to 50 Hz magnetic fields.
Hone P et al. (2006): Chromatid damage in human lymphocytes is not affected by 50 Hz electromagnetic fields.
(2006): [Statement on the final report of the REFLEX research association (5th EU Framework Program)].
Winker R et al. (2005): Chromosomal damage in human diploid fibroblasts by intermittent exposure to extremely low-frequency electromagnetic fields.
Ivancsits S et al. (2005): Cell type-specific genotoxic effects of intermittent extremely low-frequency electromagnetic fields.
Lopucki M et al. (2005): Low dose magnetic fields do not cause oxidative DNA damage in human placental cotyledons in vitro.
Scarfi MR et al. (2005): Evaluation of genotoxic effects in human fibroblasts after intermittent exposure to 50 Hz electromagnetic fields: a confirmatory study.
Crumpton MJ et al. (2004): Are environmental electromagnetic fields genotoxic?
Koyama S et al. (2004): ELF electromagnetic fields increase hydrogen peroxide (H2O2)-induced mutations in pTN89 plasmids.
Ivancsits S et al. (2003): Age-related effects on induction of DNA strand breaks by intermittent exposure to electromagnetic fields.
Pasquini R et al. (2003): Micronucleus induction in cells co-exposed in vitro to 50 Hz magnetic field and benzene, 1,4-benzenediol (hydroquinone) or 1,2,4-benzenetriol.
Ivancsits S et al. (2002): Induction of DNA strand breaks by intermittent exposure to extremely-low-frequency electromagnetic fields in human diploid fibroblasts.
Simko M et al. (2001): Micronucleus induction in Syrian hamster embryo cells following exposure to 50 Hz magnetic fields, benzo(a)pyrene, and TPA in vitro.