Detailed comparative analysis of the age and sex dependence of the influence of high-frequency EMF from mobile communications terminals on brain activity, sleep, and cognitive performance

What is the issue?

Mobile phones and smart phones are often used close the head. The brain is thus exposed to high-frequency electromagnetic fields. It has long been a question as to whether and what effects do high-frequency electromagnetic fields have on the brain, sleep, and cognitive performance, and if these are age and/or gender dependent.

What is the current situation?

The BfS has initiated four research projects on this topic since 2002. The effects of mobile communications terminals (GSM, UMTS) and public authority radio (TETRA) were investigated in healthy young men (18–30 years) as well as in older men and women (60–80 years). In all studies, minor physiological effects were found, especially on the sleep EEG. However, these were not subjectively perceptible and, according to EEG experts, do not imply any impairment of cognition or sleep. The subjective sleep quality was not significantly affected. The results of the achievement tests were only sporadically influenced and not beyond the extent expected by chance. The results of all four research projects are published in the BfS online repository DORIS (links to the reports can be found under “On the topic” at the end of the article).

What are the objectives of the BfS research project?

In previous studies, weak effects of electromagnetic fields on the brain were evident in all groups of subjects studied. These effects varied between groups. In this research project, the differences at the group level were compared using statistical methods. The aim was to determine whether there are differences in response radiofrequency fields between older and younger individuals or between women and men or whether there are more sensitive population groups depending on age and sex.

What results did the research project provide?

The present analysis has shown that a whole series of gender and age dependent differences could be determined in the sleep- and waking EEG as well as in the cognitive performance independently of the exposure. Exposure effects were significantly less common, regardless of whether they were age or gender specific or not.

The clearest effects of radiofrequency exposure were found in the sleep macrostructure and the subjective assessment of nocturnal sleep in older women and in the nocturnal EEG power of older men. The extent of the change was in the range of physiological fluctuations that can also occur between different nights without exposure within the same person and do not indicate any health impairment. On the contrary, the changes observed tend to indicate improved sleep quality, especially in older women during exposure.

With regard to waking EEG, effects of radiofrequency exposure were observed primarily in young males, with slight physiological variations within the normal physiological range.

Cognitive performance remained largely unaffected by the exposure and there were no systematic differences by age and gender.

No health impairments can be derived from the different radiofrequency exposures examined here (within the currently valid limit values) over several hours. The results confirm that although there are age- and gender-specific effects of high-frequency electromagnetic fields, these do not mean any health impairment for any of the groups of people examined if the limit values are met. Limit values protect women and the elderly just as well as young men.