[A quantitative in-vitro analysis of the effects of magnetic fields and radiofrequencies on amino acid metabolism].

: The extensive use of magnetic resonance imaging in medical diagnosis needs experimental confirmation of the real biological harmlessness of magnetic fields and radiofrequencies in the imaging process. To date, no unquestionable conclusions have been drawn and experimental results differ in various literature reports. We investigated the effects of radiofrequencies and magnetic fields on the amino acid content of plasma samples from 10 healthy volunteers aged 25 to 30 years; the samples were exposed for 60 minutes to MR fields at 0.5 T with the sequences commonly used in clinical practice. After exposure to magnetic fields, the samples were analyzed with chromatography and the results compared with those of plasma samples not exposed to MR fields. Thirty-four different amino acids were investigated and no significant changes were observed in the total concentration of any of them. Our results show that, at least in a cell-free system, exposure to a magnetic field at 0.5 T causes no significant quantitative changes in amino acid composition, at least no changes demonstrable at chromatography. On the other hand, our preliminary observation does not exclude that exposure to nonionizing radiation may modify in vivo enzyme kinetics with transient qualitative, but not quantitative, changes.