Medical/biological study (experimental study)

DNA damage, cell kinetics and ODC activities studied in CBA mice exposed to electromagnetic fields generated by transmission lines med./bio.

By: Svedenstal BM, Johanson KJ, Mattsson MO, Paulsson LE

Published in: In Vivo 1999; 13 (6): 507-513

Aim of study (acc. to author)

To investigate the effects of electromagnetic fields on mice. Possible genotoxic effects, effects on body weight, erythrocytes, leukocytes, as well as ornithine decarboxylase (ODC) activity in spleen and testis were investigated.

Endpoint

genotoxicity/mutation: DNA-damage
body weight, organ weight, leukocytes, erythrocytes, ODC activity

Exposure

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 11 days, 20 days or 32 days	magnetic flux density: 8 µT effective value

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	continuous for 11 days, 20 days or 32 days

Exposure setup

Exposure source	220 kV transmission line
Setup	Animals were placed in plastic cages with special lids to prevent eddy currents. The cages were placed in wooden boxes which were placed below the lines

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	8 µT	effective value	measured	-	-

Exposed system:

animal
mouse/CBA/Ca
whole body

Methods Endpoint/measurement parameters/methodology

genotoxicity/mutation: DNA-damage (comet assay)
effects on the immune system: hematological evaluation (leukocytes (ratio of mono- and polynucleated cells); erythrocytes (ratio of poly- and monochromatic cells))
body weight, organ weight, ODC activity (release of radioactive CO₂)

Investigated system:

DNA/RNA
intact cell/cell culture
isolated organ
tissue homogenates
investigation on living organism

Investigated organ system:

brain/CNS
thymus, spleen, testis, kidney, liver

Time of investigation:

before exposure
after exposure

Main outcome of study (acc. to author)

If all exposed animals were pooled together, the body weight was found to be statisticaly significant lower at the end of exposure compared with unexposed mice. However, no significant alteration of body weight was seen when each exposed group (11, 20, and 32 days) were examined individually. After 32 days of exposure only spleen weight was found to be statisicaly lower as compared with sham exposed animals.
After 20 days of EMF-exposure a decreased number of mononuclear leukocytes were found. Exposure for 32 days leads to a clear DNA-damage. Overall the ODC activity was not altered if all exposed animals were pooled together.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Swedish Electricians Union (SEF)/Association of Swedish Electric Utilities, Sweden

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