Medical/biological study (experimental study)

Evaluation of genotoxic effect of low level 50 Hz magnetic fields on human blood cells using different cytogenetic assays med./bio.

By: Testa A, Cordelli E, Stronati L, Marino C, Lovisolo GA, Fresegna AM, Conti D, Villani P

Published in: Bioelectromagnetics 2004; 25 (8): 613-619

Aim of study (acc. to author)

To study whether extremely low frequency magnetic fields may contribute to mutagenesis or carcinogenesis.
In a previous study (publication 10460) the authors have found that exposure of unstimulated human blood cells to 50 Hz, 1 mT for 2 h did not induce any DNA damage. The aim of this investigation is to study the potential genotoxic effect of a longer exposure time on PHA-stimulated human blood cells.

Background/further details

In order to evaluate the possible genotoxic effects of extremely low frequency magnetic fields, human blood cells were exposed in vitro. Extremely low frequency pretreated cells were also irradiated with 1 Gy of X-ray to study the possible combined effect of extremely low frequency magnetic fields and ionizing radiation.

Endpoint

genotoxicity/mutation: DNA damage

Exposure

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 48 h	magnetic flux density: 1 mT (75 V/m corresponding electric field)

General information

Each sample was divided into four aliquots namely control, positive control (12 Gy X-ray), ELF (extremly low frequency) exposed and ELF exposure followed by 1 Gy of X-ray.

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Exposure duration	continuous for 48 h

Exposure setup

Exposure source	Helmholtz coils
Chamber	Incubator maintained at 37°C and 5%CO2

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1 mT	-	measured	-	75 V/m corresponding electric field

Additional parameter details

The geomagnetic field was 40 µT

Exposed system:

blood samples

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: DNA damage (alkaline comet assay (tail moment: tail length x fraction of DNA in the tail; % tail DNA); cytogenetic assay, sister chromatid exchange and chromosome aberration (metaphase analysis); micronucleus test (frequency of micronuclei; Giemsa stain))
cell viability/cell division/proliferation: nuclear division index; proliferation index (proportion of cells that undergoes 1, 2, 3, or more divisions; metaphase analysis)

Investigated system:

DNA/RNA
intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Data do not evidence any DNA damage induced by extremely low frequency magnetic fields exposure or any effect on cell proliferation. Results obtained from the combined exposure (extremely low frequency magnetic fields and ionizing radiation) do not suggest any synergistic or antagonistic effect.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Ministero dell'Ambiente e della Tutela del Territorio e del Mar (Ministry of Environment and Territory), Italy

Zendehdel R et al. (2019): DNA effects of low level occupational exposure to extremely low frequency electromagnetic fields (50/60 Hz)
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