Impact of electromagnetic field exposure limits in Europe: is the future of interventional MRI safe?
The European Union (EU) has recently introduced a directive that aims to protect workers from adverse effects of exposure to electromagnetic fields. All countries within the EU are required to incorporate this directive into their national law by 2008. This legislation applies to all types of occupational exposure to electromagnetic fields with frequencies from 0 Hz to 300 GHz. It has dramatic implications for interventional magnetic resonance (MR) imaging, because workers who are close to the MR scanner while scanning is taking place are exposed at levels substantially above the exposure limits. This is especially the case for time-varying magnetic fields in the 110 Hz-5 kHz range, which includes the field from the imaging gradients. In this article, the scientific evidence on which the limits are based is brought into question. It is concluded that an urgent review of the directive is required and that more research, especially at MR gradient frequencies, is needed.
Hill
Derek L G
DL
Centre for Medical Image Computing (CMIC), New Engineering Building, University College London, Malet Place, London WC1E 6BT, Guy's Hospital, London, UK. derek.hill@ucl.ac.uk
McLeish
Kate
K
Keevil
Stephen F
SF
D004574:Electromagnetic Fields / Q000009:adverse effects*; D004869:Equipment Safety; D005062:European Union; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000009:adverse effects*; D016273:Occupational Exposure / Q000331:legislation & jurisprudence*