B Do Magnets Emit Harmful Radiation?

[cluelesswanderer]

Hi. No real physics background here so bare with me. Do magnets (ceramic ferrite and neodymium magnets) emit ionizing radiation? Many products use these types, including children’s magnet tiles and electronics. Can they pose a radiation and cancer risk as a result?

 

[Orodruin]

No.

 

[Orodruin]

It should be said though: Magnets can pose other risks to children. In particular small magnets when ingested. Any small parts should be kept away from children under 3, mainly because of the choking hazard. However, for magnets there are additional risks when eating them since they tend to attract. Several magnets going around in the intestines may stick together from different parts of the intestine, effectively locking the intestines together. This can lead to serious conditions that are likely to require surgery to resolve.

From a pure physics standpoint regarding radiation etc though: Magnets do not emit ionising radiation. As long as they are used as intended they do not pose any particular danger. If they did, they would certainly not be certified for use in common products.

 

[cluelesswanderer]

Thank you. I’m not sure where I read online that they have radioactive isotopes? Again, I decided to drop physics and chemistry in high school so I’m pretty dim in these topics, unfortunately. So, I ask.

 

[berkeman]

Thank you. I’m not sure where I read online that they have radioactive isotopes? Again, I decided to drop physics and chemistry in high school so I’m pretty dim in these topics, unfortunately. So, I ask.

Well, as you will find out, we do require references from valid sources. "I'm not sure where I read online..." is not valid for a continuing discussion here. This thread is closed for now, but if you can find the reference, please send me a message (PM) and we may be able to reopen this thread. Thanks.

 

[mfb]

Alpha decay of naturally occurring neodymium isotopes

Neodymium has two radioactive isotopes in its natural composition, 22.8% Nd-144 and 5.6% Nd-150, but their half lives are so long (over a quadrillion years) that this is completely negligible. So technically it is correct, it just doesn't have any practical relevance.

 

[Orodruin]

Alpha decay of naturally occurring neodymium isotopes

Neodymium has two radioactive isotopes in its natural composition, 22.8% Nd-144 and 5.6% Nd-150, but their half lives are so long (over a quadrillion years) that this is completely negligible. So technically it is correct, it just doesn't have any practical relevance.

Sure, I glossed over this since it doesn’t really matter and there are always people who will go all alarmist at the slightest mention of the word ”radioactive”.

The professor I had in nuclear physics used to tell lots of stories. One was about when a government official had visited the lab to discuss radiation limit guidelines and asked:
- What is the lowest level of activity you can measure.
When told a number they went:
- Then that’s our new upper limit.
They then had to spend a long time telling the official that would mean getting all bananas out of grocery stores among other things …

 

[PAllen]

Sure, I glossed over this since it doesn’t really matter and there are always people who will go all alarmist at the slightest mention of the word ”radioactive”.

The professor I had in nuclear physics used to tell lots of stories. One was about when a government official had visited the lab to discuss radiation limit guidelines and asked:
- What is the lowest level of activity you can measure.
When told a number they went:
- Then that’s our new upper limit.
They then had to spend a long time telling the official that would mean getting all bananas out of grocery stores among other things …

Ah yes, bananas are highly radioactive compared to batteries. Granite counter tops can dwarf any possible exposure near nuclear reactors - enough to at least give me pause (from accumulated radon in a tightly sealed house).

 

[Vanadium 50]

Granite countertops show a surprising variability in their radiation emissions.

And if you bring a survey meter into a Home Depot to measure this, a large man in an orange vest will ask you to stop.

 

[Orodruin]

And if you bring a survey meter into a Home Depot to measure this, a large man in an orange vest will ask you to stop.

And this you know from ... empirical ... studies?

 

[Nik_2213]

Was OP's question tangentially prompted by one of the many 'materials' initially proposed for 'Dark Matter' ?
IIRC, hypothesis suggested this whatever would react with 'Real World' in presence of sufficiently intense magnetic fields. 'Mechanism' akin to how current in near-by conductor may 'twist' polarisation of light.
Soon eliminated as possibility...

Peering into 'foil-beanie' country from beyond the safety fence, I'm reminded of the persistent notion that power lines may focus cosmic rays etc upon the unwary. Had an aunt who, embracing a variant of this notion, binned all her fridge magnets. Also denied the Apollo landings were 'for real'. Yet had no problem using hair-dryer, vacuum cleaner etc etc, demonstrating that too little logic is a dangerous thing....

 

[Thecla]

It may not emit radiation, but I would not want to walk into a 10,000 Gauss field.

 

[Orodruin]

It may not emit radiation, but I would not want to walk into a 10,000 Gauss field.

I don’t think there are toys with magnets that have a 10000 Gauss field …

 

[Nik_2213]

Local hospital built a nice annex for neuro-unit's powerful new NMR machine, put 'U' warning signs on outside of end-wall..
Then they re-routed foot-path from just outside end-wall, giving an extra metre or so stand-off distance.
After site-surveys revealed it was still a potential hazard to eg pace-makers and de-fib devices, never mind implanted insulin pumps and such, they diverted original path by a couple more metres. Next step when, despite those 'U' signs, this sheltered spot proved attractive to covert smokers, they fenced and 'greened' it. Finally, fenced off entire zone between annex and street, turning a real-handy --Especially in inclement weather-- short-cut into a non-trivial, 'three sides of the block' trek...

FWIW, you'd think this un-tended plot would naturally re-wild. It did, but not immediately. IIRC, there were wry comments made about 'mag-tolerant' flora & fauna, and this being the hospital's very own 'Chernobyl Exclusion Zone'...

I did wonder if there was some electrophoresis or related phenomena involved...

 

[mfb]

It may not emit radiation, but I would not want to walk into a 10,000 Gauss field.

A good permanent magnet can achieve that on its surface, but if you want something you can walk into then you need a large superconducting magnet. MRI machines have stronger fields and people are moved into them routinely.
So it's both (a) not possible with permanent magnets and (b) safe.

 

[Orodruin]

and (b) safe.

Tell that to the person going into the MRI scanner with a ferromagnetic butt plug …
https://healthimaging.com/topics/me...mri-accident-triggered-object-patients-rectum

 

[Motore]

I don’t think there are toys with magnets that have a 10000 Gauss field …

https://healthimaging.com/topics/me...mri-accident-triggered-object-patients-rectum

It depends which toys with which magnets

 

[Orodruin]

It depends which toys with which magnets

Well, not even the butt plug has an inherent magnetic field of 10000 Gauss. The problem occurs when placed in a strong external magnetic field.

The first was also referring to children's toys as discussed by OP :P