Ever since reading about the NHMFL I have always wondered about this and asked several people without getting a good satisfactory answer. My question is, considering the simplest case let's say a uniform magnetic field with a very high magnitude constant both in time and space permeating a large room, what would happen to my body in such a field like if I was to just walk through it? How large would the magnitude need to be before I "feel" anything? One tesla is fairly large, would I feel anything? I imagine as we crank up the magnitude, I would feel queasy and sick. What if I crank it up to fifty teslas or a hundred teslas? Would it hurt? Would it mess up my synaptic potentials? Would I go crazy with a dysfunctional brain? Would I pass out or go into a coma? At what point will the damage become irreversible? What magnitude will cause death? With a high enough magnitude would molecules in my body start falling apart? What happens at hundreds of teslas? Thousands of teslas or millions of teslas?
The closest thing here I found was here in the accepted answer "a magnetar that would be 1000 miles away would kill us due to diamagnetism of water in our cells". This is the kind of stuff I am looking for, the magnitude of the B-field and then its effect on a human body. Like "at 100T, your body would ________ because ______ and at 1000T, your body would ____________ because __________" and so on.
If we allow changes in the magnetic field in time, does the induced electric field "hasten" the effects somehow? Would a strong enough E-field cause a shock within us burning our organs and killing us even if the average B-field is small but the db/dt is "large" for example?
I don't know if any experiments on biological samples have been done because artificially creating magnetic fields beyond a 100T or so hasn't been quite done yet much less sustaining them and observing the effects on a biological tissue. But if there are any cool references even if they are on theoretical grounds, that would be interesting.
Thanks.
Edit: Just to make the question more answerable, I'll focus only on static fields. Anyone know of any references/experiments regarding the effects of large magnetic fields on biological tissues?
Answer
I'm only going to try to address the question of DC fields.
Medical MRI uses uniform fields of about 0.5 to 3.0 T. In a head MRI, the Lorentz force on ions in the brain can cause neurological effects such as vertigo. I've heard that this shows up in particular when the patient moves his head.
Here is a famous picture of a frog being levitated by a 16 T magnetic field. This effect requires a nonuniform field; a diamagnetic object is attracted to a region of lower field strength. I've always assumed the frog was unharmed, but I don't know for sure.
Based on this, it sounds like the result depends on whether the field is uniform or nonuniform.
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