7. What are the health risks associated with static fields?
- 7.1 What are the health risks associated with static electric fields?
- 7.2 What are the health risks associated with static magnetic fields?
7.1 What are the health risks associated with static electric fields?
Body hair movement
Few studies have been carried out on the effects of short term exposure to static electric fields. On the whole, the results suggest that the only adverse acute health effects are associated with the direct perception of fields through their interaction with body hair and discomfort from spark discharges. Chronic or delayed effects of static electric fields have not been investigated. More...
Note: For a Health Risk Assessment of Extremly Low Frequency fields (ELF), see the GreenFacts study on Power lines
7.2 What are the health risks associated with static magnetic fields?
Short-term exposure to very strong static magnetic fields seems to induce a number of acute effects. For instance, fields up to 8000 mT have occasionally led to observable effects on the heart and on blood circulation. Changes in blood pressure and heart rate have however been within the range of the normal functioning of the body.
Computer simulations suggest possible effects on the heart of electric currents induced by blood flowing through a strong magnetic field, although this has not been experimentally verified. These possible effects range from minor changes in heartbeat to an increase in the risk of abnormal heart rhythms (arrhythmia) that might be life-threatening (such as ventricular fibrillation). The magnetic field strengths at which those effects are expected to occur are difficult to assess at present because the electric currents in the heart are difficult to simulate in a computer model.
Perception of light flashes
Physical movement within a static magnetic field in which the strength changes by more than 2000 mT in a given direction (magnetic field gradient) can induce sensations of vertigo and nausea, and sometimes a metallic taste in the mouth and perceptions of light flashes. Although only temporary, such effects may be a safety concern for workers executing delicate procedures (such as surgeons performing operations using MRI).
Other acute effects of static magnetic fields have been reported, but it is difficult to reach any firm conclusion without independent replication of these results.
For static magnetic fields, the available evidence is not sufficient to draw any conclusions with regard to chronic and delayed effects. More...