Study type: Medical/biological study (experimental study)

Teratogenic effects on morphology and skeletal structure of chick embryos after exposure to 50 Hz sinusoidal electromagnetic fields. med./bio.

Published in: Iran J Sci Technol 2000; 24 (2): 173-182
Journal partially peer-reviewed/unclear

Aim of study (acc. to author)

The aims of the study were 1) to determine the extent of effects of extremely low frequency electromagnetic fields exposure (1.33-7.32 mT) on morphology and skeletal structure of chick embryos after 24 h of exposure and 2) to examine whether these biological effects were window effects or dose effects during the first 24 hours of incubation.

Background/further details

301 fresh fertilized eggs were divided into 17 groups: 15 exposure groups (1.33-7.32 mT, n = 9-16), one sham exposed group (n = 33) and control groups (n = 48-55). After 24 h exposure, the exposed and sham exposed eggs were incubated for 8 days. Control eggs were incubated for 9 days (at the end of this period the embryos were removed from their shells and investigated).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 24 hr

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Exposure duration continuous for 24 hr
Exposure setup
Exposure source
Setup 42 cm long cylindrical coil with an inner diameter of 9.6 cm and an outer diameter of 11.5 cm, consisting of 980 turns of 2.5 mm enameled copper wire, placed inside a temperature-controlled incubator
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 1.33 mT minimum calculated - -
magnetic flux density 7.32 mT maximum calculated - 1.33, 1.38 , 1.46 , 2.66 , 2.76 , 2.93 , 3.39 , 4.14 , 4.39 , 5.32 , 5.52 , 5.86 , 6.65 , 6.90 , 7.32 mT

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

All of the 15 electromagnetic field exposed groups showed an increase in the percentage of abnormalities (e.g. anencephaly, exencephaly, anophthalmia, crossed beak, gastroschisis, anuria, extra or abnormal vertebrae and ribs) compared with sham exposed and control embryos. These effects were significant in the exposure groups of 2.76, 4.14, 5.32 and 6.9 mT magnetic flux densities. The egg weights on day 9 showed no significant difference between control group and electromagnetic field exposed groups; lengths of crown-rump and beak-occipital showed no significant difference in crown-rump but there was a significant increase in beak-occipital lenth at 2.76 mT magnetic flux density; a significant decrease in embryos' weight at 7.32 mT magnetic flux density was also found.
The data revealed that 50 Hz sinusoidal extremely low frequency electromagnetic fields (with magnetic flux densities of 1.33-7.32 mT) can induce irreversible developmental changes during 24 h exposure. The findings also confirm that there are window effects.

Study character:

Study funded by

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