Medical/biological study (experimental study)

Increased DNA synthesis in INIT/10T1/2 cells after exposure to a 60 Hz magnetic field: a magnetic-field or a thermal effect? med./bio.

By: Zhao YL, Johnson PG, Jahreis GP, Hui SW

Published in: Radiat Res 1999; 151 (2): 201-208

Aim of study (acc. to author)

This study was designed to test the hypothesis that a 60 Hz magnetic field may act as a promoter of carcinogenesis in mouse fibroblasts in vitro.

Exposure	Parameters
Exposure 1: 60 Hz Exposure duration: 30 min to 24 h.	magnetic flux density: 100 µT effective value (0.8 mT.)

Exposure 1

Main characteristics

Frequency	60 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	30 min to 24 h.

Exposure setup

Exposure source	Helmholtz coils 37 cm x 37 cm placed 19 cm apart
Chamber	Forma 3158 incubators

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	100 µT	effective value	-	-	0.8 mT.

Additional parameter details

The background 60 Hz MF was less than 0.05 µT(r.m.s). Earth`s MF was 58 µT (d.c) with 59° declination.

Exposed system:

intact cell/cell culture
INITC3H 10T1/2 cells (derived from mouse embryo fibroblasts, transformed carcinogenically by methylcholanthrene, resulting neoplastic phenotype can be suppressed by the presence of retinyl acetate)

Methods Endpoint/measurement parameters/methodology

cell viability/cell division/proliferation: cell proliferation (DNA synthesis: [methyl-³H] thymidine incorporation, scintillation counter; cell counting assay)

Investigated system:

intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

No statistical significant differences in 60 Hz magentic field exposed and sham exposed cells were observed.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

National Institute of Environmental Health Sciences (NIEHS), North Carolina, USA

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