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by theyregreat 3166 days ago
Hmmm. It depends on the power, frequencies and distance to tissue. I remember a coworker at a GPS mfgr accidentially turned on a 440 MHz radio in high-power (25W) mode with only a whip antenna and received a nasty radio burn when he pointlessly/accidentally put his hand around it. That radio burn looked similar to a sunburn or maybe 20 seconds in the microwave. Increased risk of cancer, for sure.

A fraction of a Watt every now and then might be okay, as long as it’s not bursting at multiple Watts or near the resonant frequencies of purine or water.

5 comments

I thought microwaves weren't high enough in the spectrum to disrupt DNA which is the main cause of cancer risk for gamma/x-ray? Individual waves don't have the energy to break bonds even for relatively high power transmitters, at least that's what I've been told.

I'm not a comms engineer but I've also been told the biggest risk microwave exposure is thermal burns. Especially to the eyes which have limited cooling ability and pain receptors

Yeah no. Burning yourself on a hot stove does not increase your risk of cancer and that's the same thing which happened to your coworker.
A quick Google search for "burns and cancer" suggests that there may indeed be a relationship between kitchen burns and cancer.

One such result: https://www.ncbi.nlm.nih.gov/pubmed/11957286

> Abstract

> Burns are very frequent. Skin cancer on burns scars are one of the known complications....

Interesting - I didn't know that. But the parent was pretty obviously making the association between forms of damage which definitely increase cancer risk (sunburn) and non-ionizing radiation - which does not. The type of burn he observed is thermal.

So even if thermal damage (or just damage in general) can increase cancer risk a little...it's not remotely the same thing as sunburn or gamma radiation, and as it pertains to cellphones completely irrelevant (because a cellphone is not a 40W antenna emitter).

Any time you damage any part of your body, that tissue has to repair itself. There is always a chance (albeit small) of things not repairing themselves correctly and the DNA getting corrupted. Every time the same tissue has to repair itself, the odds of DNA corruption occurring increase. This is why cancer tends to manifest in areas of the body which are chronically damaged and repaired (such as an alcoholic's liver, or the esophagus of someone who has chronic heartburn, or the lungs of someone who smokes).

As such, it stands to reason that any type of burn (causing tissue damage) could ultimately lead to cancer.

Or at least that's my current understanding.

RF burns are thermal burns, but of the weirder kind. They don't heal as nicely as regular burns.

That said, getting an RF burn off an active radio element is like getting a regular burn because you've put your hand around an incandescent lightbulb. It's your fault, and it doesn't imply lightbulbs are a health danger, as in both cases the energy received diminishes by the square of your distance from the source.

> or maybe 20 seconds in the microwave

I'm curious to know the circumstances if you know what a skin burn from 20 seconds in a microwave looks like.

Many skin cancer treatments have a similar process.
Never put some pork in a microwave?
Maybe from cooking meat?
People actually cook things in microwaves? As in - they go from raw product to a cooked product? I've only ever used and only ever saw microwaves bring used for warming up meals, never for actual cooking.
For some reason the concept doesn't seem popular in many parts of the world, to the point that people don't even realize you could use a microwave to cook things[0]. But it can be, and people do. I even stumbled upon a cookbook once, that was entirely dedicated to cooking in microwave. Very interesting and insightful read. Microwave is a different beast than ovens and stoves, but if you appreciate its nature, it turns out you can do quite a lot of cooking with it.

--

[0] - This is a funny thought pattern failure that's common for people, and I don't know the better name than "acute lack of problem-solving abilities" for it. I mean, people should realize that cooking happens through heat, and microwave adds heat into a product, hence it can technically be used to cook...

Well, it's certainly doable. Though for meat in particular, people prefer to use stoves, grills, and ovens, because while a microwave can heat up meat to the point where it cooks, you really need a grill or a hot pan, for example, to induce the Maillard reaction on the surface of a steak (give it a good sear), while leaving the inside medium-rare. Try doing that in the microwave...
Checkout the buttons on the front - many have settings for cooking chicken, beef, etc.

Absolutely you can "cook" things in microwaves, people do it all the time.

What buttons? Pretty much every microwave I've ever seen looks like this[0] - timer + power setting. Even our kitchen at work which has some really fancy microwaves only offers time + power, nothing else. The ones full of buttons on the front are from like....American movies, not something I ever see in real life :P

[0] https://asda.scene7.com/is/image/Asda/5054781247296?hei=532&...

Consider multiple transmitters operating at the same time, in the same room. Even if no signal transmitter is dumping high output into that part of the spectrum, isn’t bandwidth saturation one of the reasons for poor reception and lower bars?

Would that not provide bonuses to absorbed effective wattage? There’s probably some constructive interference producing fortuitous signals, no?

When it comes to interference with DNA, it is wavelength not wattage that is important.
This is what I've always believed, but I stumbled upon this a minute ago:

https://en.wikipedia.org/wiki/Photoionization#Multi-photon_i...

Apparently, at least using some deep laser science magic, you can make photons' energy additive with respect to ionization process. Anyone here who knows the science behind this, and could shine the light on whether or not this thing has any impact on day-to-day interactions with RF radiation?

In theory, yes. In practice, wattage can disrupt tissue around, introducing radicals, etc. Dirupting DNA in the end.
The best reply to this is that we both generate a lot of radiant energy and are exposed to a lot of radiant energy in the form of sun, orders of magnitude stronger than the transmitters in our phone. The intensities the mechanism demands are neither likely or possible for everyday use