To test three alternative explanations to observed relations between magnetic field exposure and leukaemia in children
- The observed associations are due to chance.
- There is an association between cancer risk and distance between homes and power lines which is independent of the magnetic field
- The associations can be explained by confounding from some other putative risk factor such as pesticides or car exhaust.
Transmission, distribution, and use of electric power give rise to electric and magnetic fields in the extremely low frequency band (< 300 hz.). Such fields are ubiquitous in modern society. High voltage power lines are a very visible source of magnetic fields but they exist everywhere where there is electricity. There is no known mechanism by which electric or magnetic fields of this frequency and of the strength that occurs in the general environment could play a role in the development of cancer or other health effects. However, epidemiological research has indicated that there might be an association between residential and occupational exposure to magnetic fields and cancer. This research is far from conclusive but in particular for leukaemia in children the available studies are rather consistent and it is difficult to refute the hypothesis that magnetic field exposure is of importance for the origin of childhood leukaemia.
The objective of this proposal is to test three specific alternative hypotheses regarding explanations to the associations seen in the epidemiological research. This will be done by combining information from several different epidemiological research centres across Europe. By combining information from centres across Europe, two essential objectives will be achieved. First, the number of cases with elevated residential magnetic field exposure will be sufficiently large to allow for the required analyses. Second, since countries from all over Europe are included an appropriate variation in exposure conditions will be achieved which will facilitate the discrimination between the different explanations to the observed associations.