Article Text
Abstract
Introduction Magnetic Resonance Imaging (MRI) operators are exposed to significant levels of electromagnetic fields (EMF). In these workers an elevated prevalence of variuos subjective symptoms has been reported. Even if most symptoms are non-specific, in some recent studies a group of 5 more specific symptoms, defined ‘core symptoms’, was proposed: vertigo, nausea, head ringing, magnetophosphenes and metallic taste. Our aim was to investigate the prevalence of subiective symptoms, including ‘core symptoms’, in Italian MRI operators, in order to evaluate the association with exposure.
Methods A sample of 152 MRI operators working in 6 different hospitals in Italy was collected. No measurments were available, so for each participant exposure was estimated based on scanner type (<1T, 1.5T –<3T and ≥3T respectively) and on the total number of MRI procedures followed. In all operators an ad hoc questionnaire including relevant sociodemographic and occupational data, and the occurrence of subjective symptoms based our previous experience, was collected. The influence of stress was also evaluated. The relation between occupational exposure and symptoms was studied using multivariate analysis.
Result The multivariate analysis shows a significant correlation between exposure level and the total number of investigated symptoms. The results were confirmed considering the specific subset of ‘core symptoms’ based on previous literature data. In the multivariate model, the weight of the other covariate factors was not significant. The overall results were substantially confirmed considering the effect of work stress.
Discussion and conclusions In the observed group of MRI operators the total number of subjective symptoms was associated with EMF exposure; the subset of ‘core symptoms’ also proved significantly dose-related with exposure. The symptoms prevalence was not significantly influenced by work stress. The results support the association between subjective symptoms and EMF exposure in MRI operators. Another conclusion is that the appearance of the specific group of ‘core symptoms’ may be usefully investigated in health surveillance of MRI operators.