Classification of high frequency electromagnetic fields by the IARC

In May 2011, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) analysed the current knowledge of high frequency electromagnetic fields and cancer illnesses and classified these fields into Group 2B "possibly carcinogenic" on the IARC scale. This classification means that according to the estimation of the IARC, based on current knowledge, there are limited indications that high frequency electromagnetic fields have a carcinogenic effect on humans. Group 2B also includes caffeine, pickled vegetables and approximately 250 more substances. Since 2002, low frequency fields have also been classified as "possibly carcinogenic".

Classification based on limited evidence from epidemiological and animal studies

From the viewpoint of a working group convened by the IARC, high frequency fields could possibly be carcinogenic. This, however, has not yet been scientifically proven. Rather, the classification is based on limited evidence from epidemiological observation studies on humans and on limited evidence from laboratory tests on animals.

In relation to humans, studies were rated as informative and taken into consideration only if a localised exposure of the head had actually occurred. The exposure conditions corresponded to those that occur during the use of mobile or cordless telephones. A causal connection between mobile phone exposure and gliomas (malignant brain tumours) as well as acoustic neuromas (tumours of the auditory nerve) has been estimated as possible, evidence for other types of tumour is regarded as insufficient. In contrast to this, the available epidemiological studies on occupationally exposed persons have been judged by the IARC working group to be methodically limited and their results as inconsistent. An eventual correlation between environmentally relevant exposure (for example, in the surroundings of base stations) and cancer has been classified as inadequate. Among the numerous studies that were not considered for classification were investigations concerning other brain tumours, leukaemia, lymphomas, choroid tumours, testicular, breast, lung and skin cancer.

In experimental studies on animals, one out of 7 long-term studies showed an increased number of tumours. In genetically altered and/or cancer-sensitive animal models, there was an increased incidence in 2 of 12 studies and a cancer-promoting effect in 1 of 18 studies.

Hints investigated within the framework of the German Mobile Telecommunication Research Programme

Within the framework of the German Mobile Telecommunication Research Programme, the BfS has followed up these individual indications. The evidence could not be confirmed in the studies initiated by the BfS. The Federal Office for Radiation Protection has therefore ascertained that according to current knowledge, no health impairments are to be expected from high frequency fields – for example from mobile communications – if limit values are adhered to. There are, however, still uncertainties regarding the possible long-term effects of high frequency electromagnetic fields on humans, especially on children. There have not yet been any observation studies of sufficient length to evaluate these conclusively. Until today, even newly published scientific investigations have not been able to significantly reduce these uncertainties. This means that currently, possible long-term effects and effects on children cannot be ruled out (yet).

The Federal Office for Radiation Protection is one of five international scientific WHO collaborating centres, responsible among others for mobile communications. In this function, the BfS advocates continuous and forceful investigation of the remaining open questions related to the health effects of mobile communications.

Until there is a final clarification of the open questions, the Federal Office for Radiation Protection - notwithstanding the existing provisions for hazard prevention - will continue to promote precautionary reduction of individual exposure and comprehensive information for the population. The Federal Office for Radiation Protection is itself active in the fields of research, precautionary measures and information and has correspondingly given appropriate recommendations and suggestions, for example regarding individual use of mobile phones.