Study type: Medical/biological study (experimental study)

Nitric oxide level in the nasal and sinus mucosa after exposure to electromagnetic field. med./bio.

Published in: Otolaryngol Head Neck Surg 2005; 132 (5): 713-716

Aim of study (acc. to author)

To investigate the changes in nitric oxide level in the nasal and paranasal sinus mucosa after exposure to radiofrequency electromagnetic fields (900 MHz).

Background/further details

Nitric oxide plays an important role in many physiologic processes in the body including vasoregulation, hemostasis, neurotransmission, respiration and immune defense. High nitric oxide levels were found in paranasal sinuses and it was thought that a decreased concentration of nitric oxide might contribute to the pathogenesis of sinusitis.
The rats were randomly grouped: group 1: EMF exposure; group 2: EMF and melatonin application; group 3: control group.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Modulation type: CW
Exposure duration: repeated daily exposure, 30 min/day, 5 days/week for 2 weeks

General information

Animals were randomly allocated to three groups receiving the following treatment: EMF exposure, EMF exposure and oral melatonin, and sham exposure (control group).

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Exposure duration repeated daily exposure, 30 min/day, 5 days/week for 2 weeks
Modulation
Modulation type CW
Exposure setup
Exposure source
Chamber The exposure system consisted of a ventilated plastic tube cage (length 12 cm; diameter 5.5 cm) and a half-wave dipole antenna.
Setup The whole bodies of the rats were positioned in close contact above the antenna (near field).
Additional info Before the EMF exposure, animals were anesthetized with pentobarbital Na. Oral melatonin (10 mg/kg) was given with water daily following the EMF exposure. Control rats were also placed in the tube, but without exposure to EMF.
Parameters
Measurand Value Type Method Mass Remarks
power 2 W peak value - - -
power density 1.04 mW/cm² mean measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Exposure to EMF released by mobile phones (900 MHz) significantly increased the nitric oxide levels of nasal and paranasal sinus mucosa. However, there was no statistically significant difference between group 2 (EMF and melatonin) and the control group regarding nitric oxide output. Increased nitric oxide levels may act as a defense mechanism and presumably related to tissue damage. In addition, melatonin may have beneficial effect to prevent these changes in the mucosa.

Study character:

Study funded by

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