Is there an increased risk of leukemia, brain tumors or breast cancer after exposure to high-frequency radiation?

Background: There are only a few epidemiologic studies investigating risk f actors in persons occupationally exposed to high-frequency radiation (e. g. radio-, TV-waves, mobile phones or microwaves). The results of the studies are mostly inconsistent. Methods: All epidemiologic studies which investigated the association betwe en occupational exposure to high-frequency radiation and the risk of leukem ia, brain tumors or breast cancer were included in this review. All studies published between 1980 and 1997, such as record-linkage, case-control, and cohort studies, were retrieved from MEDLINE. Incidence and mortality studi es are included. Methodologic problems of these investigations are discusse d. Results: Most of the recent epidemiologic studies do not present quantitati ve exposure data or data on the specific frequencies of electro magnetic fi elds. In general, the relative risks for leukemia, brain tumors or breast c ancer are small, not significant and inconsistent. Confounder variables wer e not included in most of the analyses and no dose-response relationship wa s reported. Conclusion: To increase the power and the validity of the studies a re-anal ysis based on original data of all previous studies in this field is recomm ended. Additionally, to investigate the influence of high-frequency radiati on on the development of cancer international epidemiologic studies are nec essary. Only they would have sufficient sample size to detect small elevate d risks.