EMF-Portal | Perturbations of plant leaflet rhythms caused by electromagnetic radio-frequency radiation

Perturbations of plant leaflet rhythms caused by electromagnetic radio-frequency radiation med./bio.

Aim of study (acc. to author)

Electromagnetic pulses at known frequencies and intensities were used to perturb the lateral leaflet movements of Desmodium gyrans.

Background/further details

The movements were studied before and after pulse exposure using either a pure sine-shaped electromagnetic field at 27.12 MHz or a 27 MHz sine-wave which was amplitude modulated by a 50 Hz sine-wave signal.

Endpoint

lateral leaflet movement

Exposure

Exposure	Parameters
Exposure 1: 27.12 MHz Modulation type: single pulse Exposure duration: 30, 60, 150 s pulses	power density: 8 W/cm² minimum power: 300 W maximum magnetic field strength: 3.75 A/m maximum (1.25- 3.75 A/m.) power density: 530 mW/cm² maximum (0.059-0.53 W/cm².) electric field strength: 471 V/cm maximum (1.414-471 V/m.)
Exposure 2: 27 MHz Modulation type: AM, single pulse Exposure duration: 30, 60, 150 s pulses	power density: 8 W/cm² minimum magnetic field strength: 3.75 A/m maximum (1.25- 3.75 A/m.) power density: 5.3 W/m² maximum (0.059-0.53 W/cm².) electric field strength: 417 V/m maximum (1,414-471 V/m.)

Modulation type	single pulse
Additional info	pulse width was manually controlled

Exposure source	dipole antenna TEM Cell, Crawford, terminated with 50 Ohm
Chamber	cylindrical perspex holder, 25mm diameter, 35mm high

Measurand	Value	Type	Method	Mass	Remarks
power density	8 W/cm²	minimum	cf. remarks	-	-
power	300 W	maximum	cf. remarks	-	-
magnetic field strength	3.75 A/m	maximum	cf. remarks	-	1.25- 3.75 A/m.
power density	530 mW/cm²	maximum	cf. remarks	-	0.059-0.53 W/cm².
electric field strength	471 V/cm	maximum	cf. remarks	-	1.414-471 V/m.

radiation dose D = 31.8 Ws/cm²

Modulation type	AM, single pulse
Modulation frequency	50 Hz
Additional info	Pulse width manually controlled

Exposure source	dipole antenna commercial diathermy equipment
Chamber	cylindrical perspex holder, 25mm diameter, 35mm high
Setup	different distances from the so-called dipole

Measurand	Value	Type	Method	Mass	Remarks
power density	8 W/cm²	minimum	cf. remarks	-	-
magnetic field strength	3.75 A/m	maximum	cf. remarks	-	1.25- 3.75 A/m.
power density	5.3 W/m²	maximum	cf. remarks	-	0.059-0.53 W/cm².
electric field strength	417 V/m	maximum	cf. remarks	-	1,414-471 V/m.

radiation dose D = 31.8 Ws/cm²

Exposed system:

Methods Endpoint/measurement parameters/methodology

lateral leaflet movement

Investigated system:

Time of investigation:

Main outcome of study (acc. to author)

Changes in amplitude, period, phase, and temporary or complete cessation of the leaflets' motions were observed.

Study character:

Study funded by

Norwegian Konsesjonsfondet, Norway

Star Information Systems (SIS) Oslo, Norway