Medical/biological study (experimental study)

Effects of long-term 50 Hz magnetic field exposure on the micro nucleated polychromatic erythrocyte and blood lymphocyte frequency and argyrophilic nucleolar organizer regions in lymphocytes of mice med./bio.

By: Okudan N, Celik I, Salbacak A, Cicekcibasi AE, Buyukmumcu M, Gokbel H

Published in: Neuro Endocrinol Lett 2010; 31 (2): 208-214

Aim of study (acc. to author)

To study the effects of 50 Hz magnetic fields with different magnetic flux densities on the cell nucleus area, some silver staining nucleolar organizer regions (AgNOR) parameters and the frequency of the micronucleated polychromatic erythrocytes and peripheral blood lymphocytes.

Background/further details

120 mice were divided into six groups (each group n=20) for the sham exposure and five different magnetic flux densities.

Endpoint

genotoxicity/mutation: micronucleus formation in blood cells
blood cell characteristics

Exposure

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 40 days	magnetic flux density: 5 µT effective value (1, 2, 3, 4, 5 µT)

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	continuous for 40 days

Exposure setup

Exposure source	solenoid
Setup	six solenoids, each consisting of 300 turns of insulated copper wire wound in a single layer on a 32 cm diameter cylindrical plastic core; 10 animals of the same sex housed in one plastic cage; cage placed in the center of the solenoid
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	5 µT	effective value	calculated	-	1, 2, 3, 4, 5 µT

Reference articles

Mevissen M et al. (1994): Effects of static and time-varying (50-Hz) magnetic fields on reproduction and fetal development in rats

Exposed system:

animal
mouse/Swiss albino
whole body

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: micronucleus formation (number of micronucleated polychromatic erythrocytes and lymphocytes; modified Giemsa staining, light microscopy)
blood cell characteristics (cell nucleus area and silver staining of nucleolar organizer regions (area and AgNOR number per nucleus; as marker for nucleolus activity and transcription)
body weight, food and water consumption

Investigated system:

intact cell/cell culture
blood samples
investigation on living organism

Investigated organ system:

immune system

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The extremely low frequency electromagnetic field exposure caused a nonlinear decline of the nucleus area compared with the sham exposed control group. A sharp drop occurred in AgNOR area of 1 µT group, and the data showed a regular increase with increased magnetic flux densities. The electromagnetic field did not change mean AgNOR numbers per nucleus of the groups. Relative AgNOR area had the highest level in 1 µT exposure group, and the level was quite similar to that of the 5 µT group. The remaining groups had significantly lower values quite similar to that of the control level.
The magnetic field exposure at any intensity did not affect significantly the frequency of the micronucleated blood cells. Nevertheless, micronucleus number per lymphocyte tended to increase at higher magnetic flux densities.
The results suggest that ≤ 5 µT intensities of 50 Hz magnetic fields did not cause genotoxic effects in the mouse.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Selcuk University, Turkey

Udroiu I et al. (2015): Genotoxicity induced by foetal and infant exposure to magnetic fields and modulation of ionising radiation effects
Alcaraz M et al. (2014): Effect of long-term 50 Hz magnetic field exposure on the micronucleated polychromatic erythrocytes of mice
Miyakoshi Y et al. (2012): Tempol suppresses micronuclei formation in astrocytes of newborn rats exposed to 50-Hz, 10-mT electromagnetic fields under bleomycin administration
Udroiu I et al. (2010): Genotoxic properties of extremely low frequency electromagnetic fields
Cakir DU et al. (2009): Alterations of Hematological Variations in Rats Exposed to Extremely Low Frequency Magnetic Fields (50Hz)
Vijayalaxmi et al. (2009): Genetic damage in mammalian somatic cells exposed to extremely low frequency electro-magnetic fields: a meta-analysis of data from 87 publications (1990-2007)
Cicekcibasi AE et al. (2008): Determination of the effects of extremely low frequency electromagnetic fields on the percentages of peripheral blood leukocytes and histology of lymphoid organs of the mouse
Udroiu I et al. (2006): Clastogenicity and aneuploidy in newborn and adult mice exposed to 50 Hz magnetic fields
McNamee JP et al. (2005): Evaluating DNA damage in rodent brain after acute 60 Hz magnetic-field exposure
Vijayalaxmi et al. (2005): Controversial cytogenetic observations in mammalian somatic cells exposed to extremely low frequency electromagnetic radiation: a review and future research recommendations
Lai H et al. (2004): Magnetic-field-induced DNA strand breaks in brain cells of the rat
McNamee JP et al. (2002): DNA damage and apoptosis in the immature mouse cerebellum after acute exposure to a 1 mT, 60 Hz magnetic field
Abramsson-Zetterberg L et al. (2001): Extended exposure of adult and fetal mice to 50 Hz magnetic field does not increase the incidence of micronuclei in erythrocytes
Svedenstal BM et al. (1999): DNA damage, cell kinetics and ODC activities studied in CBA mice exposed to electromagnetic fields generated by transmission lines
Svedenstal BM et al. (1999): DNA damage induced in brain cells of CBA mice exposed to magnetic fields
Svedenstal BM et al. (1998): Leukocytes and micronucleated erythrocytes in peripheral blood from mice exposed to 50 Hz or 20 kHz magnetic fields
Lai H et al. (1997): Acute exposure to a 60 Hz magnetic field increases DNA strand breaks in rat brain cells
Lagroye I et al. (1997): The effect of 50 Hz electromagnetic fields on the formation of micronuclei in rodent cell lines exposed to gamma radiation
Cantoni O et al. (1996): Effect of 50 Hz sinusoidal electric and/or magnetic fields on the rate of repair of DNA single strand breaks in cultured mammalian cells exposed to three different carcinogens: methylmethane sulphonate, chromate and 254 nm U.V. radiation