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Are microwaves bad for you?

It often strikes me that the operative word for many people is the dreaded 'RADIATION'. It scares the s**t out of people and particlularly those of an age to remember the horrors which emerged from the 'casual' use of Radium products in the early 20thC. Also obviously those who were a bit chronologically closer to the whole Hiroshima/Nagasaki thing and the post WWII arms race.

So, I have known people who believed that Microwave ovens somehow made food 'radioactive'. which is of course rubbish.

If we get over the idea that microwave radiation has any sort of lasting presence once the source (the magnetron) is switched off.. we then have those who fear 'leakage'. It clearly can happen, hence the admonitions by manufacturers not to dismantle microwave equipment, use kit with faulty doors etc., etc. But, the only effect of microwaves from ovens on human anatomy would be to cause burns, and ISTM that this is far more likely to happen with any form of 'conventional' oven heated by gas, electricity or solid fuel.

From Wiki:
Direct microwave exposure
Further information: Microwave burn and Microwave § Effects on health
Direct microwave exposure is not generally possible, as microwaves emitted by the source in a microwave oven are confined in the oven by the material out of which the oven is constructed. Furthermore, ovens are equipped with redundant safety interlocks, which remove power from the magnetron if the door is opened. This safety mechanism is required by United States federal regulations.[54] Tests have shown confinement of the microwaves in commercially available ovens to be so nearly universal as to make routine testing unnecessary.[55] According to the United States Food and Drug Administration's Center for Devices and Radiological Health, a U.S. Federal Standard limits the amount of microwaves that can leak from an oven throughout its lifetime to 5 milliwatts of microwave radiation per square centimeter at approximately 5 cm (2 in) from the surface of the oven.[56] This is far below the exposure level currently considered to be harmful to human health.[57]

The radiation produced by a microwave oven is non-ionizing. It therefore does not have the cancer risks associated with ionizing radiation such as X-rays and high-energy particles. Long-term rodent studies to assess cancer risk have so far failed to identify any carcinogenicity from 2.45 GHz microwave radiation even with chronic exposure levels (i.e. large fraction of life span) far larger than humans are likely to encounter from any leaking ovens.[58][59] However, with the oven door open, the radiation may cause damage by heating. Every microwave oven sold has a protective interlock so that it cannot be run when the door is open or improperly latched.

Microwaves generated in microwave ovens cease to exist once the electrical power is turned off. They do not remain in the food when the power is turned off, any more than light from an electric lamp remains in the walls and furnishings of a room when the lamp is turned off. They do not make the food or the oven radioactive. Compared to conventional cooking, the nutritional content of some foods may be altered differently, but generally in a positive way by preserving more micronutrients - see above. There is no indication of detrimental health issues associated with microwaved food.[60]

There are, however, a few cases where people have been exposed to direct microwave radiation, either from appliance malfunction or deliberate action.[61][62] The general effect of this exposure will be physical burns to the body, as human tissue, particularly the outer fat and muscle layers, has similar composition to some foods that are typically cooked in microwave ovens and so experiences similar dielectric heating effects when exposed to microwave electromagnetic radiation.

Chemical exposure
Some magnetrons have ceramic insulators with beryllium oxide (beryllia) added. The beryllium in such oxides is a serious chemical hazard if crushed then inhaled or ingested. In addition, beryllia is listed as a confirmed human carcinogen by the IARC;[citation needed] therefore, broken ceramic insulators or magnetrons should not be handled. This is a danger if the microwave oven becomes physically damaged, if the insulator cracks, or when the magnetron is opened and handled, yet not during normal usage.

Much of the fear of microwaves seems to me to derive from either 'guilt by association' ( by erroneous association with ionising radiation) or a simple failure to understand the physics.

The most extreme example of the 'Guilt by Association' approach I've seen was some ultra vegan bloke on the telly who said he would never consider eating tomatoes, because they were from the 'same family' as Deadly Nightshade. (Solanum) This of course is true, but then so are potatoes and aubergines among others, not to mention the whole Capsicum family of peppers and chillies, also part of the Solanaceae. This whole approach is analagous to refusing to eat onions because daffodils are poisonous.

Mull
 
Microwave ovens use 2.4 GHz because it is a resonance of the water molecule and is well absorbed by food. This choice of frequency lead to the band becoming an ISM band and relatively unregulated - hence its use for WiFi.
3G and 4G is relatively unabsorbed by water, otherwise rain would stop you making a call.

Microwave ovens are tested to leak very low levels of stray power, 1mW/cm2
 
I am about to microwave the remains of last nights deep fried fish and chip supper. Please wish me luck.
 
Soggy Batter alert there then. Yuck. Chips not much better either.

Reheating Fish and Chips much better in a conventional oven, or even (with care) a grill
 
Soggy Batter alert there then. Yuck. Chips not much better either.

Reheating Fish and Chips much better in a conventional oven, or even (with care) a grill

I know but needs must and it was a choice between the fish'n'chips and the half eaten big mac that has been in the desk drawer for a couple of days (the latter also requires a knife to scrape off the fatty blue residue that has appeared).........

I am at work and we only have a microwave and a toaster, and I am not sure I want to put my battered cod in a toaster. Anyway, microwaving adds positive benefits in terms of flavour.

I could of course go and find the kiln I know the Creative Arts people have or one of the blow torches from Engineering
 
This Microwave is really good for you.

waldorf_microwave.jpg


Stephen
 
Steve 67
Your posts demonstrate that your strident assertions do not prove anything except your need to refute with verbiage .
And you are calling ME verbose?

As for impartiality, there are literally millions of microwaves in use, all over the world, all over the UK, in commercial premises and homes, and they have been in use for 30-40 years. Where are all the deaths and injuries? No serious study has shown up a problem provided the door is shut. The problem with speaking to conspiracy theorists is that they only want to believe their pet scientist, such as you have found, and even after 40 years it's impossible to prove a negative, just as you can't prove my elephant deterrent isn't effective.

It's the easiest thing in the world for you to say "you're biased" and impossible for me to prove I'm not. However I can say that I spend my working day dealing with any number of real food hazards. Look at the list from the FSA as a starter. Microwaves are not on the list. Nor is the mobile phone in your pocket, nor are FM radio transmissions. I have nothing to gain or lose whatever from the use (or not) of microwaves. Hoever nothing I can say will change your mind, which is fine by me. You cook your food as you wish. However do give over telling us that domestic microwave cookers are dangerous until you have some better proof than your deluded scientist with an axe to grind.
 
Microwave ovens use 2.4 GHz because it is a resonance of the water molecule and is well absorbed by food. This choice of frequency lead to the band becoming an ISM band and relatively unregulated - hence its use for WiFi.
3G and 4G is relatively unabsorbed by water, otherwise rain would stop you making a call.

Microwave ovens are tested to leak very low levels of stray power, 1mW/cm2

I tend to be wary of regarding the choice being for water 'resonance' reasons. In liquid any such LF resonance will tend to be quite broad, and made even broader or less significant by the tendency for whatever is in the oven to contain other things, so not simply be water. The water, etc, have sufficient absorption for it to work OK, though.
 
FWIW This is a topic area I've revisited more than once over *decades*. What had struck me is how those waving their hands about tend to change what causes them to do so. Not so long ago it was 'TETRA'. At another time it was the *magnetic* fields produced by powerlines - despite the powerlines being relatively high-impedance. (i.e. 'more E than H' in simple terms). I did once spend months wading such 'studies' to help a local MEP try and decide what to make of it.

Main conclusion was that people tend to worry about things for reasons like the above-mentioned. e.g. see terms like 'radiation' or that a microwave oven is 'higher power' than a mobile phone, or simply make sweeping assumptions without knowing much about EM propagation, etc.

If you want to worry about such things I'd say your main anxiety would be over sticking a mobile to your ear when using it. You are then close to a high impedance antenna. And if you use earphones/buds to get some distance, it may be using the *lead* as the antenna. 8-] Chances are your exposure to 'field levels' is rather higher than when using a microwave oven to heat a mug of coffee. *Billions* of people have been using the mobile phone/comm devices for tens of billions of person-years.

That said, maybe this is why so many people voted for Trump, etc... 8-]
 
The worst exposure is the American APCO P25 police radio. They usually wear the 5W VHF radio on the belt and pressed against the kidneys. The human body is just the right size to be resonant at VHF, so the field strength will be very high.
 
The worst exposure is the American APCO P25 police radio. They usually wear the 5W VHF radio on the belt and pressed against the kidneys. The human body is just the right size to be resonant at VHF, so the field strength will be very high.

Maybe they use the radios to keep themselves warm when 'on the beat' during a cold spell. 8-]
 


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