Medical/biological study (experimental study)

Microsatellite analysis for determination of the mutagenicity of extremely low-frequency electromagnetic fields and ionising radiation in vitro med./bio.

By: Mairs RJ, Hughes K, Fitzsimmons S, Prise KM, Livingstone A, Wilson L, Baig N, Clark AM, Timpson A, Patel G, Folkard M, Angerson WJ, Boyd M

Published in: Mutat Res Genet Toxicol Environ Mutagen 2007; 626 (1-2): 34-41

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Aim of study (acc. to author)

This in vitro study was performed to explore the mutagenic effect of extremely low frequency electromagnetic field in human glioma cells.

Background/further details

The mutagenic effect was determined by the microsatellite analysis.
Three types of mutation were investigated: 1.) change in allele size, 2.) loss of heterozygous state (as a result of a deletion in one cell at the time of irradiation) and 3.) alleles imbalance (occuring several cells divisions after the radiation insult).
Cells were unexposed (control group), electromagnetic field exposed and co-exposed (electromagnetic field plus gamma radiation).

Endpoint

genotoxicity/mutation: microsatellite mutations

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 12 h continuous	magnetic flux density: 1 mT

General information

cells were treated in the following ways: i) 0 Gy gamma-irradiation + EMF ii) 0.3 Gy gamma-irradiation + EMF iii) 3 Gy gamma-irradiation + EMF

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Exposure duration	12 h continuous

Exposure setup

Exposure source	solenoid
Setup	2 solenoids, 300 mm long with a diameter of 120 mm each, consisting of 400 turns of 1.5 mm copper wire with additional 52 turns of wire at either end of the coils, that could be energised seperately; uniformity of the field inside the solenoids > 99 %; cells placed in T25 flasks inside the solenoids
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1 mT	-	-	-	-

Exposed system:

intact cell/cell culture
UVW (human glioma cell line)

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: microsatellites mutations: 1.) change in allele size, 2.) loss of heterozygous state and 3.) alleles imbalance (PCR, gel chromatography, fluorescent DNA fragment analysis)

Investigated system:

DNA/RNA

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The exposure of the cells to extremely low frequency electromagnetic field alone at a field strength of 1mT (50 Hz) for 12 hours showed a 3.75-fold increase in mutation induction compared with the unexposed control group.
The co-exposure revealed an increase in the mutagenic effect of 0.3 and 3 Gy gamma radiation. Moreover, the treatment with 0.3 Gy induced more than 10 times more mutations per unit dose than radiation with 3 Gy.
These results clarify not only that extremely low frequency electromagnetic field is mutagenic as a single agent but also that it can potentiate the mutagenicity of ionizing radiation.

Study character:

medical/biological study
experimental study
full/main study
blind study

Study funded by

Clerk Maxwell Cancer Research Fund (CMCRF), UK
Department of Health, UK
North Glasgow University Hospitals, UK

Mun GI et al. (2015): Effects of 60-Hz magnetic fields on DNA damage responses in HT22 mouse hippocampal cell lines
Wilson JW et al. (2014): The effects of extremely low frequency magnetic fields on mutation induction in mice
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
Sakurai T et al. (2009): Intermediate frequency magnetic fields generated by an induction heating (IH) cooktop do not affect genotoxicities and expression of heat shock proteins
Burdak-Rothkamm S et al. (2009): DNA and chromosomal damage in response to intermittent extremely low-frequency magnetic fields
Cho YH et al. (2007): Effects of extremely low-frequency electromagnetic fields on delayed chromosomal instability induced by bleomycin in normal human fibroblast cells
Ivancsits S et al. (2005): Cell type-specific genotoxic effects of intermittent extremely low-frequency electromagnetic fields
Winker R et al. (2005): Chromosomal damage in human diploid fibroblasts by intermittent exposure to extremely low-frequency electromagnetic fields
Cho YH et al. (2003): The effect of extremely low frequency electromagnetic fields (ELF-EMF) on the frequency of micronuclei and sister chromatid exchange in human lymphocytes induced by benzo(a)pyrene
Ivancsits S et al. (2003): Intermittent extremely low frequency electromagnetic fields cause DNA damage in a dose-dependent way
Ivancsits S et al. (2003): Age-related effects on induction of DNA strand breaks by intermittent exposure to electromagnetic fields
Ding GR et al. (2003): Induction of kinetochore-positive and kinetochore-negative micronuclei in CHO cells by ELF magnetic fields and/or X-rays
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. (1998): Effects of 50 Hz EMF exposure on micronucleus formation and apoptosis in transformed and nontransformed human cell lines
Simko M et al. (1998): Micronucleus formation in human amnion cells after exposure to 50 Hz MF applied horizontally and vertically
Nordenson I et al. (1994): Chromosomal aberrations in human amniotic cells after intermittent exposure to fifty hertz magnetic fields