Microwave oven: mode and harmfulness

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delnoram
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by delnoram » 14/10/07, 21:50

I guess the question is for Maximus Leo?

But I read the same thing here

Unlike polyethylene recuperators, precast concrete tanks reduce the natural acidity of rainwater, thanks to the alkaline elements that the concrete contains. This property is all the more necessary for urban areas and their peripheries where rainwater is particularly acidic because of air pollution.
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by Leo Maximus » 15/10/07, 14:57

citro wrote:I have not yet read the subject on onoucachetout but I read elsewhere that the use of a concrete tank to store and decant rainwater greatly improved its qualities and erased its defects ...
Can you confirm or deny it? :?:

I've read that too, but it's mostly about new concrete. It should be noted that most of the tiles of today are no longer in terra cotta but in colored concrete. There must certainly be a small difference in pH between the water that has dripped on a clay tile roof, on a roof made of concrete tiles and the one that comes from a rain gauge ... I did not measure The pH of the rainwater I used in the experiment on plants but I will do it next time.

For the cooling experiment it would be necessary to start from a boiling water prolonged so that the temperature is uniform and stable. The water starts to boil at 90 ° (I am however only at an altitude of 30 meters), 95 ° boils quite strongly and to reach the maximum temperature, close to 100 °, wait at least one minute .

Here again I am at 100% convinced that the microwave oven has no influence but the important thing is to make the demonstration.
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by elephant » 15/10/07, 20:27

You make me laugh a bit with

Unlike polyethylene recuperators, precast concrete tanks reduce the natural acidity of rainwater, thanks to the alkaline elements that the concrete contains. This property is all the more necessary for urban areas and their peripheries where rainwater is particularly acidic because of air pollution.


It's true, but the concrete is eaten: go see in the caves ... when you put the time!
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by Christine » 15/10/07, 20:41

Caves in concrete ?? Are they bunkers? : Cheesy:
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by I Citro » 16/10/07, 21:32

:? We're not straying here ...

Well we now know that the water heated in the microwave does not cooled faster than the water heated more traditionally. 8)
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by Leo Maximus » 17/10/07, 13:18

I did a pH test of my rainwater. Result the pH is neutral! :

Image

Image

Plants and seeds sprinkled with water boiled in microwaves (or in electric kettle) grow better than when they are watered with rain water ... It is a fact that I observed by carrying out the Experience several times. It was a big surprise because all the gardening sites tout the merits of rainwater. This is not due to the acidity of the rainwater since its pH is neutral.
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by Christophe » 24/02/12, 18:29

Gross subject digging with this article: http://www.terraeco.net/Le-micro-ondes- ... 42121.html From Terraeco

No less than 85% of French households have one at home. Without necessarily knowing its operation and its effects. Terra eco looked into the matter.

As with 85% of French households, my kitchen is equipped with a microwave oven. It's convenient, it saves me from multiplying the dishes, because doing the dishes does not burst out more than that. And then when my belly cries famine, I like to be able to support it as quickly as possible. Because the microwave is very fast. But is it safe?

- How does my chicken-broccoli-puree come out of the fridge warm up?

"The microwave oven uses the thermal properties of radio frequencies," says the Health and Radio Frequencies Foundation, whose mission is to encourage research efforts on the effects of electromagnetic waves on people. "Microwaves are actually electromagnetic waves with an alternating electric field," says physicist Jean-Michel Courty, a professor at Pierre and Marie Curie University.

It is the magnetron, a tube capable of producing waves, which converts the electric current of the sector having a frequency of 60 Hz into electromagnetic radiation of 2,45 giga Hz. In short, this means that these waves oscillate 2,45 billions of times per second . At the same rate they vibrate the water molecules contained in the food. The movement of these molecules produces friction, collisions and this causes a rapid rise in temperature. When the oven is switched off, microwaves disappear almost instantaneously (one microsecond, one millionth of a second).

- Where can I put my bowl of soup to warm it up?

Immediate answer: it is on the edge of the turntable, not at the center of this tray, that we need to put feeding bottles, dishes, bowls for optimal heating efficiency. Why ? Because, as Jean-Michel Courty explains on his blog Ideas of physics, (see here and then also there), the heating is not homogeneous. The waves do not have the same intensity in all parts of the oven, and some parts of the food are more exposed than others. This is why the tray is rotating. And if you put your bowl in the heart of your oven, it turns in circles, on itself, and is therefore always exposed to the same waves.

- Why do not I put an egg in its shell to cook in the microwave?

Never heat a tightly closed product (such as an egg or a well-sealed lid)! And why ? Because the water molecules in food give off steam by heating. If the container is closed, it creates an overpressure and therefore there is risk of explosion. An egg in its shell in the microwave is like a grain of corn. Except that you would not really get popcorn ...

- Does the microwave oven change the composition of my food?

This question anxious many consumers who seem to believe that eating a cooked or warmed dish on the turntable turns out to catch a cancer by mouth. False. Archi-false, hammer Patrick Le Dévéhat, technical director of Gifam the federating organization of industrial appliances. "Microwaves are not Gama or X rays, they are neither irradiating nor radioactive, they do not change the DNA of food, they only heat them," he says. The Health and Radiofrequency Foundation agrees that "there is no transformation of the material and thus no creation of molecules dangerous to health during this operation" of cooking or heating by microwaves.

To the "mystics who believe that we do not tell them everything" and who are disturbing this heating power and totally invisible, Patrick Le Dévehat answers: "Do not go to the beach! For if in an oven, the frequency of the waves rises to 2.45 giga Hz, that of the infrared sensed by the skin in the sun is from 300 to 800 000 giga Hz! "

There is, however, one study carried out in 1991 by two Swiss scientists, Hans Hertel and Bernard H. Blanc, who relates the consumption of foods cooked in the microwave oven and abnormal increase in the number of white blood cells in the blood . But this assertion has not been validated by other scientific studies, which conclude on the contrary to the innocuity of this method of cooking for the consumer.

In addition, the European Food Information Council, a non-profit organization with the ambition to provide the general public with information on food safety, notes that "the highest energy levels Microwaves tend to reduce cooking times. " Therefore, "the amount of vitamins remaining after this type of cooking is sometimes more important than after a traditional cooking".

- Can microwaves escape from the oven and "pierce" me?

Microwave manufacturers, be they French, American or Chinese, are all aligned on the 60-335-2-25 standard. Established thirty years ago, it sets the international level of microwave safety and the maximum level of leakage tolerated. This threshold is set at 50 watts / square meter, at 5 centimeters from the device in operation. A threshold that would not cause your cheeks to warm up if he took you the crazy idea of ​​sticking your face to the door of your microwaves on the move.

And even if the oven door were to lose its tightness (due to a blow or poor maintenance), Patrick Le Dévéhat swears: "The very complex tests that the manufacturers put on their products show that the consumer is out of danger. The CE marking that manufacturers must obtain to market their products on the European market (and obtained if they comply with the Low Voltage Directive which regulates these products) attests to this.

"The powers coming out of a microwave in operation, a few milliwatts, are insufficient to cause a significant heating," adds physicist Jean-Michel Courty. The World Health Organization says nothing else. Moreover, "it takes only a microsecond for the electromagnetic field to stop when the door opens," explains the physicist. This applies to the inside of the oven as well as to the food that comes out of it: since they are no longer crossed by waves, they do not release any.

- Can I rush to my plate as soon as I take it out of the oven?

The records of microwave ovens advise the consumer to be more patient than me, and wait ten to twenty seconds before eating or eating what he has just cooked or reheated. "It is the same principle as to finish the cooking of a dish by turning off the gas or electricity a few minutes before, while putting a lid on the pan (saving a little energy, note): The food water molecules continue to be agitated and therefore to heat, "says Patrick Le Dévéhat.

Good sense of economics to which are added considerations related to the safety of the consumer. Especially when he heats a drink. In fact, liquids in the microwave reach or even exceed their boiling point but show no signs (such as the formation of bubbles). Now, like me, you are in a hurry to add your dose of soluble coffee in hot water. But be careful, "you can cause a spontaneous boil that blows you up in the face", failing to burn you severely enough, comments Jean-Michel Courty who experiences it in this video (76 minute). To avoid the accident, it is better to wait a few tens of seconds before shaking the water.

- Why, when I heat my soup, my bowl is sometimes hot but not my vegetables?

"It depends on the material in your container. Recall that in the microwave deploys an electric field which agitates the electrons of the products present in the furnace. So if your bowl is glass or, better, in Pyrex, which are materials without electrical charge or water molecules, it will not heat. On the other hand, putting a flat metal, steel or aluminum, which are very conductive, will cause sparks. Not to do ! Other materials absorb energy from the microwave, such as ceramics, and therefore heat. This is the principle of the special pie plates sometimes supplied with the oven and which heat. This is also why you can cook your pizza in the microwave. Thank you Jean-Michel Courty, we would not have said better.
The microwave oven more energy efficient than other cooking methods?
Students from the College and Business School Nicolas Bouvier, Switzerland, conducted an interesting experiment in 2008. They looked for the most energy efficient way to heat 3 water deciliters to 100 ° C. At this little game, the kettle is the fastest and most energy efficient mode of heating. It is ahead of the microwave oven. Then come the hot plate and then the gas stove. Regarding the heating of the dishes (the kettle is therefore removed from the stroke), the advantage goes to the microwave oven because there is no loss of heat to the outside, as is the case for a Pan placed on a plate or a stove.
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by Christophe » 24/02/13, 11:30

A complete article on the harmfulness of the microwave oven ... brrrr ....
http://actuwiki.fr/dossier/12473

Practical side: cooking without fat, time saving realized, ease of use, very convenient to defrost: yes but at what price?

In 1945, the war having ended brutally, magnetron stocks were high, especially in the United States. (The magnetrons are the pulse generators producing radar waves.) It was as a result of the skin burns of the personnel using the radars that an American firm thought about recycling its stock of magnetrons. Some researchers, such as Dr. Percy-Spencer, allowed the manufacture of industrial and then household furnaces.
The principle of using the microwave is still mysterious for many of us. Yet everyone knows that a hot body is a body whose molecules are in motion. It is therefore sufficient to agitate molecules to increase the temperature. The magnetron takes care of it. This electron tube produces electromagnetic waves: microwaves, which owe their name to their mini wavelength (from 1 to 3 mm).
Normally, in the microwave oven, several devices prevent their leakage: the metal grid, which returns them towards the inside of the oven, the glass door, also metal-framed that bar the passage, the joints that border this door By providing sealing, of cavities called "wave traps" from which they do not emerge. When the ovens operate, these waves agitate the water molecules of the food very quickly, causing them to heat up: "microwave ovens use electromagnetic waves of very high frequency: 2450 megahertz (for a kiln calibrated to 2,45 Ghz) a wavelength close to that of military radars, which means that in one second, the water molecules contained in the food placed in the furnace change 2,45 billion of orientation time, resulting in friction Intense intentions which are at the origin of the warm-up.
Now, all our foods contain water and an apple cooked in less than two minutes! On the other hand, bodies that do not contain water (glass, glass ceramic, plastic ...) do not heat: this explains the first danger of these ovens: the burns of infants. The bottle thus heated appears fresh but the milk it contains reaches the 80 ° C!

THE NEFAST EFFECTS OF MICROWAVE OVENS ON OUR HEALTH

1 - leaks

The ovens are never completely watertight. Professor Jean Paul Pellissier of Claude Bernard University in Lyon, monitors their leaks in the microwave research laboratory: "These leaks are particularly dangerous when they occur on industrial devices, much more powerful than those used in The kitchens, and before which workmen stand eight hours a day.
For example, this machine, forty times more powerful than yours, is used to stick the wood and its entrance is always open since a worker is constantly pushing boards.
In this type of work, the leakage of waves could present a real danger of burning. But as far as the housewife is concerned, Professor Pellissier wants to be reassuring: "Of course, there are minimal leaks at this level, but they are of the order of 1 to 5 milliwatts per cm². "
Yet Professor Herbert Koning of the University of Munich, who tested new kilns, just out of the factory, says that 15% of them have leaks above tolerable standards! And this does not manage over the uses.
Roger Santini, a researcher in the laboratory of pharmacodynamic physiology of INSA (National Institute of Applied Sciences), is worried: "in time, joints degrade, wave traps get clogged and users" clink " Levels! ".
For example at eye level. One has to worry when the children stick their face to the door to watch turn the dishes! Metal prosthesis wearers should also be wary of possible heat build-up, and attention should be drawn to the potential damage to the pacemaker in the event of leakage.
For all these reasons, Roger Santini wishes to impose on the manufacturers an after-sales service ensuring the safety of the users.
In the meantime, there are small leak detectors (sold at a reasonable price) in the supermarkets which are sufficiently reliable for a household user.
But microwave waves have other specific effects that have been described as early as 1956 on soldiers exposed to radars. These various effects can be characterized by:

Hyperthermia: Gays and Jonhson demonstrated in 1972 that microwave energy is unevenly distributed: the energy absorbed can therefore cause local thermal stimulation or macroscopic effects on different organs depending on the level of exposure.

The eye: the ocular lesions caused by microwaves seem to be mainly of thermal origin. However, non-thermal effects can not be excluded, but they do not appear to be sufficient to cause ocular lesions, although they can provide an interaction mechanism essential to the formation of lesions. People with contact lenses may be prone to eye inflammation, the lenses concentrating the waves in the eyes.
Neuro-Endocrine / Nervous System Effects: Several elements of the neuroendocrine apparatus exhibit extreme sensitivity at room temperature so that the effects of microwaves with low energy density can be explained by sensitivity to Small variations in temperature. These effects are fatigue, asthenia, dizziness, instability of mood, confusion, insomnia ...
The alteration of the electroencephalogram as well as the appearance of convulsions in workers exposed to microwaves for more than three years in the course of their work have been observed.
Blood system and immunocompetent cells: Deichman (1964) Kotkouska and Waak (1975) found numerous disorders: hyperleukocytosis (increase in the number of white blood cells), decreased concentration of erythrocytes (blood cell transporting oxygen from lungs to tissues) , And hemoglobin, lymphocytosis (increase of lymphocytes: the lymphocytes are the cells of the immune system, responsible for the defense reactions of the organism against the substances that it considers foreign), etc ... The modification of the number of the globules White or red appears to depend on the applied dose. The effects would be due to the thermal stress imposed by irradiation.
Disturbance of the hormonal system / reproduction and development: this leads to irregularity, disruption of the menstrual cycle and even disappearance of menstruation in women who are accidentally exposed to high doses.
Irradiation can affect reproductive and developmental mechanisms. Experimentally we find lesions in the testicles and in particular an alteration of the spermatogenesis. It should also be borne in mind that these frequencies affect blood and microorganisms (molecular chain, amino acids ...) and penetrate the fat on nearly 5 cm, the brain between 0,5 and 1 cm, the spinal cord being affected in Its totality. It is obvious that injuries will only be felt after a certain amount of exposure time.
For years, the Americans have established a maximum allowable power density of 5 milliwatts per cm² for microwave ovens leaving the factories, the Soviets of 1 microwatt per cm². Yet in France, there are still no standards.
2 - denatured foods

Even more serious than leaks, these devices denature the food. The sensitive crystallization test (for more information) shows that the microwave oven is the most common way to disrupt the food and alter its vital energy.

After a long study, Madame Bourgeay Causse of the Institut Pasteur concluded that tastes changed little after this type of cooking. In 1989, the British accused the microwave of causing food poisoning.
A study done on the other hand shows that bacteria such as listeria or salmonella are not destroyed after heating.
Professor Joyeux of the University of Montpellier describes the disturbances in the structures: "microwaves deplete food in water-soluble vitamins of group B and group C which are quite unstable vitamins. "

But the most disturbing is revealed in a study published by the very serious medical journal "The Lancet" and carried out by Austrian researchers from the Department of Pediatrics of the University of Vienna (Austria).

Milk samples were heated in the microwave and analyzed. Some proteins have been altered in their structure: for example, L-Proline has become D-Proline, a neurotoxic product. The Austrian researchers (Lubec Wolf and Bartosch) also note a new toxicity in the kidneys and liver due to the amino acids thus transformed.
A Japanese study (1968) showed that the fatty acids undergo (peroxidation) a peroxidation - oxidation of the fats by the free radicals. This reaction is the cause of many diseases, in particular cardiovascular diseases. We speak of peroxidation in the language of chemists or of rancidity according to the vocabulary of housewives - with formation of free radicals (cellular aging, atherosclerosis, activation of the process of cancerisation.

3 - Remaining waves

Finally, it should be noted that the food still radiates for about 10 mn after leaving the oven.
Ingurgities during this period, they are likely to lead to digestive disorders. Everyone knows how much water is in the human body, so let's imagine the damage! And when you see mothers heating baby bottles in their microwaves, you may wonder if babies so "treated" will not suffer A disadvantage as to their future health: this molecular agitation interferes with our own cells according to modalities that are still ill-defined but certainly disturbing (there would be, in particular, production of free radicals in the cells of the consumer, in addition to those Formed in the food).
This type of cellular interaction is all the more sensitive in a growing organism, and therefore in children (intense synthesis during the first months of life: we know that milk proteins are undermined by microwaves , But what happens in the baby whose bottle is heated so no one knows)!

Thus, taking into account the risks of electromagnetic pollution due to the effects of microwave waves, as well as the deterioration of the food by internal cooking at high temperature and vibration, as well as the very probable harms of the microwave, Persistent molecular agitation during ingestion, it seems expensive to pay the time that one is supposed to gain compared to methods of cooking without fats which, they, respect the food and preserve the health.

Article written by Catherine Martinez relayed by Cuisiner Autrement
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by culbuto » 24/02/13, 11:45

Leo Maximus wrote:
citro wrote:8) Well, it makes our life easier. For if we had actually measured a significantly different cooling time between the water heated to the pan or the boulloire and the water heated in the microwave it would have been difficult to find the explanation ... : Lol:

Always be wary of rumors and peremptory statements.

Already, in a microwave oven, the container can heat or not heat depending on the material, the porcelain remains cold, the terracotta quickly becomes burning while the liquid it contains remains cold! In addition the heating of the liquid is not uniform, that is why we have the turntable because the magnetron is on one of the sides. To carry out a study of the cooling time microwave / stove I think it should first be brought to the boil and then transfer the water uniformly hot in two identical containers. Obviously under the control of a bailiff! To silence the rumors, we have more useful things to do ...

The experience I conducted on onnouscachetout.com taught me that rainwater was not the best for plants! I have an aquarist friend who told me that putting rainwater in an aquarium is the best way to get fish to die. Rainwater = mistrust therefore.

It may be seen as an effect of acidification due to CO2 in the air. to check.
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by Christophe » 24/02/13, 11:52

Christophe wrote:A complete article on the harmfulness of the microwave oven ... brrrr ....


ps: there is a stupidity in the beginning of the article, the microwaves do not heat food water but all bipolar molecules (already said above I think) ... so oils and fats also heat up microwave (that's why the meats are very fast hot).

A complete file: http://www.bag.admin.ch/themen/strahlun ... ml?lang=fr
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