Base station and handset: short-term effects
Short-term health effects due to electromagnetic fields can be assessed on the basis of the limits recommended by the ICNIRP . As mentioned above, emissions from handsets and base stations are well below these limits. Accordingly, short-term health effects are not to be expected with the use of cordless telephone handsets or base stations.
Handset: long-term effects
The ICNIRP recommendations on limits do not, however, cover possible long-term effects of electromagnetic radiation. Such effects are currently being investigated in a number of epidemiological studies. Although this research is mainly focused on the health effects of mobile phone emissions, several studies also include emissions from cordless phone handsets. In this regard, a German study found no association between cordless phone use – even over a period of more than 5 years – and the occurrence of brain tumours . In contrast, a recent Swedish study concludes that elevated risks of brain tumours are found in particular when cordless phones have been used for many years . The same Swedish research group investigated the association between the use of cordless phones and testicular cancer . They could not find any association. Additional the Interphone study, coordinated by the International Agency for Research on Cancer (IARC) could not give conclusive answers about the possible association between mobile phone emissions and brain tumours. These results would have been relevant for cordless phones as well. Thus, at present, no consensus exists concerning long-term effects of emissions from cordless phone handsets.
The association between unspecific symptoms of ill-health and self-reported sleep disturbances with the use of cordless phones was investigated in epidemiological studies. No consistent association between subjective sleep quality and cordless phone was found [11-13]. Additionally, cordless phone use does not seem to influence the function of the brain blood barrier .
Base station: long-term effects
No specific studies are currently being conducted on the long-term effects of cordless phone base stations. With regard to possible health effects of weak high-frequency emissions, such as those that occur with these base stations, the small number of studies available do not yield any firm conclusions. Since 2007, some studies on the relation between subjective well-being and exposure to different radiofrequency electromagnetic fields (including DECT base stations) was investigated [11,15]. No consistent association between exposure and well-being was found.
Interference with implants
According to a German study, neither base stations nor handsets cause interference with pacemakers or defibrillators .