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I got exposed to toxic material of a thermometer...
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SiliconWizard:

--- Quote from: Zero999 on August 23, 2023, 08:49:53 pm ---It's not just magnetism which is the hazard of MRI. The RF can induce currents which result in heating. It depends on the impedance of the metal. If it's very low, it'll just reflect, whist if it's a bit higher, it'll heat up.

--- End quote ---

Yep. The induced currents may also destroy the device or harm you if said device is an active one (even though most manufacturers of active implantable devices now make sure to have at least some MRI compatibility.) In any case, always make sure to mention any implantable device you may have before having an MRI, however small it is and active or not. Or it could end up pretty badly.
WatchfulEye:
In addition to the risk active device malfunction/destruction, active devices have a particular issue which is that they tend to use insulated wires. This geometry is particularly bad for heating. The insulation means that currents can't leak into tissue and can be concentrated at the ends, leading to high current densities around electrodes.

This gets even worse if the orientation of the wires is parallel to the static magnetic field (typically head-foot orientation), and can get dramatically worse if you hit a length which acts like a resonant monopole antenna (roughly 25 cm for a typical MRI scanner operating at 64 MHz/1.5T).   

The development of techniques for qualifiying devices for MRI compatability has progressed greatly over recent years. As a result modern devices tend to have much better compatability and much clearer instructions than older ones.
Infraviolet:
Mercury in the eueballs has quite a history to it, doctors used to use it as the standard procedure for getting metal dust/shavings out of eyes. They'd dribble in some Mercury and let it "dissolve"* the other metal particulates. I guess they assumed the Mercury would somehow leak away over time.

*somehow Mercury and Gallium, the room temperature liquid metals, attack any other metal in such a way as to weaken the structure and make it fall apart in to a sludgy mix. Mercury is famed for attacking aluminium, but it and Galllium have similar effects on steel and other metals too.

P.S. great joke about that doctor's thermometer and his lack of astrological bullsh*t
Smokey:

--- Quote from: Infraviolet on August 24, 2023, 01:52:07 pm ---Mercury in the eueballs has quite a history to it, doctors used to use it as the standard procedure for getting metal dust/shavings out of eyes......

--- End quote ---

Damn you angle grinders!  My eyes are way out of balance on my metal dust to mercury ratio...

"... she swallowed the spider to catch the fly ... "
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