Medical/biological study (experimental study)

Micronucleus frequency and cell proliferation in human lymphocytes exposed to 50 Hz sinusoidal magnetic fields med./bio.

By: Scarfi MR, Lioi MB, Zeni O, Della Noce M, Franceschi C, Bersani F

Published in: Health Phys 1999; 76 (3): 244-250

Aim of study (acc. to author)

The effects of 50 Hz sinusoidal magnetic fields on micronucleus induction and cell proliferation in human lymphocytes should be examined.

Background/further details

Peripheral lymphocytes were obtained from blood samples of 42 healthy donors aged between 26 and 54 years.

Endpoint

genotoxicity/mutation: DNA damage
cell viability/cell division/proliferation: cell proliferation

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 72 h	magnetic flux density: 0.05 mT effective value magnetic flux density: 0.25 mT effective value magnetic flux density: 0.5 mT effective value magnetic flux density: 0.75 mT effective value magnetic flux density: 1 mT effective value

General information

blood samples were divided into five groups and treated with: a) 0.05 mT b) 0.25 mT c) 0.5 mT d) 0.75 mT e) 1.0 mT or sham exposed

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	72 h

Exposure setup

Exposure source	Helmholtz coils
Setup	H.-coil pair, 21cm diameter, 80 turns (double wrapped) of 2 mm copper wire; coils horizontally in incubator; Plexiglas layer in middle of coil structure hosted samples
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.05 mT	effective value	measured	-	-
magnetic flux density	0.25 mT	effective value	measured	-	-
magnetic flux density	0.5 mT	effective value	measured	-	-
magnetic flux density	0.75 mT	effective value	measured	-	-
magnetic flux density	1 mT	effective value	measured	-	-

Exposed system:

intact cell/cell culture
human lymphocytes

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: DNA damage (micronucleus frequency: cytokinesis block micronucleus assay)
cell viability/cell division/proliferation: cell proliferation (cytokinesis-block proliferation index)

Investigated system:

DNA/RNA
intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

No statistically significant differences were observed in spontaneous micronucleus induction.
A slight variation in the proliferation index was found: increased cell proliferation at 1 mT magnetic flux density, and decreased at magnetic flux density of 0.05 mT. The effect was small, but statistically significant.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

National Research Council (CNR; Consiglio Nazionale delle Ricerche); Italy

Jin YB et al. (2014): Absence of DNA damage after 60-Hz electromagnetic field exposure combined with ionizing radiation, hydrogen peroxide, or c-Myc overexpression
Jin YB et al. (2012): Effects on micronuclei formation of 60-Hz electromagnetic field exposure with ionizing radiation, hydrogen peroxide, or c-Myc overexpression
Rajendra P et al. (2012): Viability of unstimulated lymphocytes exposed to extremely low frequency electromagnetic fields is dependent on intensity
Erdal N et al. (2007): Cytogenetic effects of extremely low frequency magnetic field on Wistar rat bone marrow
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
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
Ding GR et al. (2003): Induction of kinetochore-positive and kinetochore-negative micronuclei in CHO cells by ELF magnetic fields and/or X-rays
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
Heredia-Rojas JA et al. (2001): Cytological effects of 60 Hz magnetic fields on human lymphocytes in vitro: sister-chromatid exchanges, cell kinetics and mitotic rate
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
Supino R et al. (2001): Sinusoidal 50 Hz magnetic fields do not affect structural morphology and proliferation of human cells in vitro
Johnson MT et al. (2001): Electromagnetic fields used clinically to improve bone healing also impact lymphocyte proliferation in vitro
Zeni O et al. (2001): Combined exposure to extremely low frequency (ELF) magnetic fields and chemical mutagens: Lack of genotoxic effects in human lymphocytes
Scarfi MR et al. (1997): 50-Hz, 1-mT sinusoidal magnetic fields do not affect micronucleus frequency and cell proliferation in human lymphocytes from normal and Turner's syndrome subjects