Blettner M, Schlehofer B, Breckenkamp J, Kowall B, Schmiedel S, Reis U, Potthoff P, Schuez J, Berg-Beckhoff G. Mobile phone base stations and adverse health effects: Phase 1: A population-based cross-sectional study in Germany. Occup Environ Med. Ahead of print November 18, 2008.
Studies done in houses close to mobile phone base stations have found that the levels of radiofrequency electromagnetic fields (RF-EMF) are well below acceptable safety limits. However, 40% of European Union (EU) citizens surveyed thought that these base stations affected their health. This could be due to the “nocebo” effect, where expectation of adverse effects will cause such effects. Alternatively, the adverse health effects could be due to long-term low-level exposure to RF-EMF, about which little is known.
The objective of the study was to investigate whether risk perception posed by mobile phone base stations, as well as proximity of residence to mobile phone base stations are associated with health complaints in the German population.
A person aged 14-69 was randomly selected per household from a sample of 51,444 households representative of the German population. Participants were asked to rank the severity of any health complaints they experienced (e.g. cognition problems, pain, sleeping problems). They were also asked if they were worried about the health effects of mobile phone base stations (concern) and whether they believed their health was adversely affected by base stations (attribution). Participants were asked to estimate the distance between their dwelling and the next mobile phone base station. These estimates were compared with measured values.
A total of 30,161 individuals responded to the invitation to participate in the study (58.6%). Nearly one in five people (18.7%) who filled in the questions on concerns and attribution was concerned about the health effects of mobile phone base stations and one in ten (10.3%) attributed adverse health effects to RF-EMF from mobile phone base stations. People with higher social status (income and education) were more concerned than others but had a lower prevalence of attribution. Those who believed they lived within 500 meters of a mobile phone base station were more likely to report concerns than other participants. Those who were concerned about the health effects or attributed them to RF-EMF exposure from base stations were more likely to experience more severe health complaints than those without concerns or attribution. Those living within 500 meters of a base station had slightly more severe health complaints than those living more than 500 meters away.
Interpretation and Limitations
An association was found between attribution of adverse health to mobile phone base stations and more severe health complaints. It is unclear whether those with health complaints attribute these to mobile phone base stations in an attempt to identify the cause of their health complaint or whether high levels of anxiety, depression, and stress over the perceived health hazard of living in proximity of the mobile phone base station promote health complaints. The major limitation of this study is the low response rate (below 60%) and the crude measure of exposure to RF-EMF as distance from the nearest base station.
Concerns about health effects of mobile phone base stations and attribution of health effects to mobile phone base stations are common in the German population and are associated with health complaints. The weak finding of more severe health complaints in those living within 500m of a base station warrants further study.