Study type: Medical/biological study (observational study)

Response of Pinus sylvestris L. needles to electromagnetic fields. Cytological and ultrastructural aspects. med./bio.

Published in: Sci Total Environ 1996; 180 (1): 65-73

Aim of study (acc. to author)

To examine the impact of radiofrequency electromagnetic fields of the Skrunda radar station on growth and development of pine trees.

Background/further details

In a previous study of Balodis et al. 1996, it was shown that exposure to the Skrunda radar station decreased the radial growth of pine trees. In the present study, ultrastructural effects were examined in order to understand the changes.
Pine needles and cones were collected in 1993/94 in four different areas (pine forests) near the Skrunda station: 1. area) no exposure (0.04 mV/m), 2.) low exposure (9.5 mV/m), 3.) high exposure (79.4 mV/m) and 4.) very high exposure (250 mV/m).
The seeds were planted and grown in a glasshouse. Second year needles were analyzed.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 154–162 MHz
Modulation type: pulsed
Exposure duration: continuous
Exposure 2: 154–162 MHz
Modulation type: pulsed
Exposure duration: continuous
Exposure 3: 154–162 MHz
Modulation type: pulsed
Exposure duration: continuous
Exposure 4: 154–162 MHz
Modulation type: pulsed
Exposure duration: continuous

General information

Pulse level of the Skrunda radar could have intensities of 375 µW/cm² or more.

Exposure 1

Main characteristics
Frequency 154–162 MHz
Type
Exposure duration continuous
Modulation
Modulation type pulsed
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 0.04 mV/m - measured - -

Exposure 2

Main characteristics
Frequency 154–162 MHz
Type
Exposure duration continuous
Modulation
Modulation type pulsed
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 9.5 mV/m - measured - -

Exposure 3

Main characteristics
Frequency 154–162 MHz
Type
Exposure duration continuous
Modulation
Modulation type pulsed
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 79.4 mV/m - measured - -

Exposure 4

Main characteristics
Frequency 154–162 MHz
Type
Exposure duration continuous
Modulation
Modulation type pulsed
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 250 mV/m - measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

All seeds from the area with low exposure germinated (100 %), while 85 % of the unexposed seeds germinated. However, only 55 % and 27 % of the seeds obtained from areas with high exposure (areas 3 and 4, respectively) germinated.
In the needles from the young pines, grown from seeds which were collected from low and high exposed areas (area 2, 3 and 4), an increased amount of plastoglobules (globular formation made of lipids; a marker of stress response) was found compared to those not exposed. Additionally, near golgi apparatus, large osmiophilic globules (a characteristic chloroplast component) were found in the needles obtained from exposed seeds in comparison to needles belonging to unexposed seeds.
The authors suppose that pulsed radiofrequency electromagnetic fields could lead to an unspecific stress response, such as accelerated resin production and promoted senescence of pine trees and hence influence the radial growth.

Study character:

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