Study type: Medical/biological study (experimental study)

Effects of Power Frequency Electromagnetic Fields on Growth of Germinating Vicia faba L., the Broad Bean. med./bio.

Published in: Electromagn Biol Med 2005; 24 (1): 39-54

Aim of study (acc. to author)

To study the effect of continuous and delayed exposure of power frequency electromagnetic fields at 5, 50 and 100 µT on germinating Vicia faba (Broad Bean) seedlings as a model system.

Background/further details

Different measurements were performed at 2, 4, and 8 days of growth.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for up to 8 days
total exposure
Exposure 2: 50 Hz
Exposure duration: continuous for 4 days
delayed exposure
Exposure 3: 50 Hz
Exposure duration: continuous for 12 hours
imbibition

General information

Vicia faba seeds were weight matched, disinfected and activated by soaking them overnight in Hoagland's solution at room temperature (25 ± 2°C). They were divided into: Group I - control Group II - exposed to varying magnetic field intensities viz. 5.0 ± 0.25, 50 ± 2.5, or 100 ± 5 µT, at 50 Hz, till lateral roots were formed (day 8, termed total exposure) Group III - grown outside the field until germination as evidenced by formation of the primary root (day 4) and then shifted into the varying magnetic field for the lateral root formation (termed delayed exposure). A separate study was also undertaken to evaluate the effect of different magnetic field intensities on the imbibition of Vicia faba seedlings which were soaked in Hoagland medium and exposed for 12 hours (overnight).

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Exposure duration continuous for up to 8 days
Additional info total exposure
Exposure setup
Exposure source
Setup The magnetic field exposure facility was comprised of 24 wooden boxes (size 0.5 m x 0.5 m x 0.5m). Individual bobbins were wound around each box forming two sets of horizontal coils (each set consists of 50 turns) and three sets of vertical coils (each set consists of 25 turns), capable of producing horizontal, vertical, circular and elliptical magnetic fields. The vertical coils were movable and their position was adjusted so as to obtain a uniform magnetic field intensity inside the exposure area which was ensured by measurement. Coefficient of variation was found to be <6% over the whole volume of the bobbin.
Additional info A similar set-up having 12 numbers of bobbins was established without energizing the coils for control. Enough spacing (2.78 m) was provided between the control and experimental groups to avoid any interference of the magnetic fields. The geomagnetic field inside the boxes was: Z (vertical) = 15.894 ± 0.141 µT and H (horizontal) = 39.430 ± 0.013 µT.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 µT - measured - ± 0.25 µT
magnetic flux density 100 µT - measured - ± 5 µT
magnetic flux density 50 µT - measured - ± 2.5 µT

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Exposure duration continuous for 4 days
Additional info delayed exposure
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 µT - measured - ± 0.25 µT
magnetic flux density 100 µT - measured - ± 5 µT
magnetic flux density 50 µT - measured - ± 2.5 µT

Exposure 3

Main characteristics
Frequency 50 Hz
Type
Exposure duration continuous for 12 hours
Additional info imbibition
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 µT - measured - ± 0.25 µT
magnetic flux density 100 µT - measured - ± 5 µT
magnetic flux density 50 µT - measured - ± 2.5 µT

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

There was no significant change in physical parameters and biochemical constituents between control and experimental plants.
The comparison between the control and exposed seedlings showed that α-amylase enzyme activity significantly decreased at 5, 50 and 100 µT on day 2 and 4 of growth. β-amylase and protease showed a significant decrease in enzyme activities on day 2 and 4 at 100 µT, whereas enzyme activity of lipase significantly decreased only on day 2 of growth at 100 µT.
At day 8 of growth, all enzyme activities reverted back to the same as control.
There was also a significant increase in ³H-thymidine uptake as well as in mitotic index at 100 µT ("delayed exposure" (group III) on day 8; field 2).
The data suggest that exposure to power frequency electromagnetic fields up to 100 µT on germinating seedlings does not cause any permanent damage since the initial alteration in some important enzymes under the magnetic field exposure were returned to control values on day 8 of growth.

Study character:

Study funded by

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