170Association between exposure to MRI-related magnetic stray fields and symptoms reported by workers in the public health and research sector

ObjectivesThis study aims to assess which acute symptoms are prevalent among health care and research staff working with MRI scanners, and whether these are related to their exposure to static magnetic stray fields.MethodsFourteen health care and research MRI facilities were surveyed. Full-shift measurements of exposure to static and time-varying magnetic fields (SMF and TVMF) among staff were collected using personal dosimeters. Participants filled out one to two forms per shift, on which they reported their activities and symptoms they had experienced during (part of) their working day. Fourteen target symptoms were included which had been reported in literature in association with exposure to MRI-related SMF and TVMF . A subgroup of five 'core' symptoms was defined based on stronger (statistical) evidence for their association with SMF and TVMF exposure. Six additional unrelated symptoms were included to control for over-reporting of symptoms in general.ResultsIn total, 1,056 forms were completed by 334 participants. Nine out of 14 target symptoms were reported more frequently among staff exposed to SMFs, compared to unexposed staff. The proportion of forms on which at least one target symptom was reported increased with increasing scanner field strength. This trend was even stronger when focusing on the five 'core' symptoms. Strongest associations were seen for nausea, vertigo, metallic taste, and feeling of instability. No association was seen for the subgroup of unrelated symptoms.ConclusionsAn increased number of symptoms was reported by staff working in the static magnetic stray field of an MRI-scanner. A clear trend of increased symptom reporting with increasing scanner field strength underlines the potential that a causal relation exists between exposure to MRI stray fields and specific symptoms.