280 male rats were induced chemically (nitrosurea) with B acute lymphoblastic leukemia. The animals were exposed in four replicate experiments to a 50 Hz magnetic field of 100 µT (with or without harmonics), the limit recommended for public exposure by international guidelines. Different experimental groups were studied: 1) rats induced with leukemia without exposure; 2) rats induced with leukemia + exposure; 3) rats induced with leukemia + exposure + harmonics; 4) negative controls (no induced leukemia, no exposure). Another group of 160 rats was used as positive control which were partly pre-treated with gamma radiation.
animals were treated in four groups: i) rats treated with BNU, no EMF exposure ii) rats treated with BNU + exposure to 50 Hz EMF iii) rats treated with BNU + exposure to 50 Hz EMF with harmonics superimposed iv) control = no treatment
The results did not show significant differences between exposed and non-exposed rats for any of the measured parameters. Significant changes in the leukemia type obtained after gamma radiation of the leukemia model, showed its sensitivity to a physical agent.
The results do not support the hypothesis that extremely low frequency electromagnetic fields, with and without harmonics, affect the development of B acute lymphoblastic leukemia.