Medical/biological study (experimental study)

Effects of pulsed high-frequency electromagnetic fields on the neuroendocrine system med./bio.

By: Mann K, Wagner P, Brunn G, Hassan F, Hiemke C, Roeschke J

Published in: Neuroendocrinology 1998; 67 (2): 139-144

Aim of study (acc. to author)

To investigate the influence of pulsed high-frequency electromagnetic fields in the lower microwave frequency range generated by a digital mobile telephone on the neuroendocrine system (hormone secretion) in healthy humans.

Endpoint

endocrine changes: hormone secretion

Exposure

- mobile communications
- digital mobile phone
- GSM

Exposure	Parameters
Exposure 1: 900 MHz Modulation type: pulsed Exposure duration: continuous for 8 h	power density: 0.02 mW/cm² mean (at 40 cm)

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Polarization	circular
Exposure duration	continuous for 8 h

Modulation

Modulation type	pulsed
Pulse width	577 µs
Repetition frequency	217 Hz

Exposure setup

Exposure source	cellular phone GSM system, amplifier
Distance between exposed object and exposure source	40 cm
Chamber	The subjects slept in a specially constructed metal-free bed that was enclosed in a metal-free chamber lined with RF-absorbing material.
Setup	The antenna was positioned beneath the head of the bed at a distance of 40 cm to the vertex of the subject and was operated from the neighbouring room via an extension lead.
Sham exposure	A sham exposure was conducted.
Additional info	After an adaptation night, polysomnographies were performed during two successive nights. The subjects were exposed in one night and sham-exposed in the other night (randomized and blinded).

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power density	0.02 mW/cm²	mean	-	-	at 40 cm

Measurement and calculation details

The function of the antenna could be monitored from the neighbouring room, the applied pulse and field intensity being shown on an oscilloscope.

Exposed system:

human
partial body: head

Methods Endpoint/measurement parameters/methodology

endocrine changes: nocturnal hormone profiles of growth hormone (immunoradiometric assay), cortisol (radioimmunometric assay), luteinizing hormone (LH; immunoenzymometric assay), and melatonin (radioimmunometric assay)
polysomnography (EEG; EOG; ECG; EMG)

Investigated system:

isolated bio./chem. substance
investigation on living organism

Investigated organ system:

Time of investigation:

during exposure

Main outcome of study (acc. to author)

The only significant effect found was an interaction between field exposure and time for cortisol concentration. This indicates an alterated temporal secretion pattern of cortisol under exposure. A transient elevation in the cortisol serum level immediately after onset of field exposure was found which persisted for 1h. For growth hormone, luteinizing hormone, and melatonin, no significant effects were found under radiation compared to the placebo condition, regarding both total hormone production during the night and dynamic characteristics of the secretion pattern. The evaluation of the sleep EEG data revealed no significant effects under radiation compared to the placebo condition. However, an indication of an REM sleep suppressive effect could be found. The data indicate that weak high-frequency electromagnetic fields have no effects on nocturnal hormone secretion except for a slight elevation in cortisol production which is transient (pointing to an adaption of the organism to the stimulus).

Study character:

medical/biological study
experimental study
pilot/exploratory/preliminary study

Study funded by

Deutsche Telekom/T-Systems, Germany

Geronikolou SA et al. (2015): Frequent cellular phone use modifies hypothalamic-pituitary-adrenal axis response to a cellular phone call after mental stress in healthy children and adolescents: A pilot study
Eskander EF et al. (2012): How does long term exposure to base stations and mobile phones affect human hormone profiles?
Augner C et al. (2010): Effects of Exposure to GSM Mobile Phone Base Station Signals on Salivary Cortisol, Alpha-Amylase, and Immunoglobulin A
Djeridane Y et al. (2008): Influence of electromagnetic fields emitted by GSM-900 cellular telephones on the circadian patterns of gonadal, adrenal and pituitary hormones in men
Lerchl A et al. (2008): Effects of mobile phone electromagnetic fields at nonthermal SAR values on melatonin and body weight of Djungarian hamsters (Phodopus sungorus)
Wood AW et al. (2006): Does evening exposure to mobile phone radiation affect subsequent melatonin production?
Koyu A et al. (2005): No effects of 900 MHz and 1800 MHz electromagnetic field emitted from cellular phone on nocturnal serum melatonin levels in rats
Vangelova KK et al. (2005): Variations of melatonin and stress hormones under extended shifts and radiofrequency electromagnetic radiation
Koyu A et al. (2005): Effects of 900MHz electromagnetic field on TSH and thyroid hormones in rats
Ozguner M et al. (2005): Biological and morphological effects on the reproductive organ of rats after exposure to electromagnetic field
Bakos J et al. (2003): GSM modulated radiofrequency radiation does not affect 6-sulfatoxymelatonin excretion of rats
Jarupat S et al. (2003): Effects of the 1900 MHz electromagnetic field emitted from cellular phone on nocturnal melatonin secretion
Wenzel C et al. (2002): [Response to ACTH of cows under exposure to high-frequency electromagnetic fields]
Burch JB et al. (2002): Melatonin metabolite excretion among cellular telephone users
Braune S et al. (2002): Influence of a radiofrequency electromagnetic field on cardiovascular and hormonal parameters of the autonomic nervous system in healthy individuals
Bortkiewicz A et al. (2002): The excretion of 6-hydroxymelatonin sulfate in healthy young men exposed to electromagnetic fields emitted by cellular phone - An experimental study
Radon K et al. (2001): No effects of pulsed radio frequency electromagnetic fields on melatonin, cortisol, and selected markers of the immune system in man
de Seze R et al. (1999): Evaluation in humans of the effects of radiocellular telephones on the circadian patterns of melatonin secretion, a chronobiological rhythm marker
de Seze R et al. (1998): GSM radiocellular telephones do not disturb the secretion of antepituitary hormones in humans
Vollrath L et al. (1997): No short-term effects of high-frequency electromagnetic fields on the mammalian pineal gland