Mikrogolf – microwave

 
Daar is net op hierdie een artikel heelwat besprekings oor die gebruik van die mikrogolf, verskillende artikels waarna verwys word en universiteite / persone wat reageer het.    Just for information – there are more.   Lots of debate on this. Some interesting publications listed below.

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It all started with Hans Hertel.

The Swiss food chemist and seven fellow vegetarians confined themselves to a hotel for two months in the late 1980s.   There, they consumed milk and vegetables prepared in the microwave oven and in other ways.   Hertel emerged with an astonishing pronouncement.   Eating microwaved milk and vegetables caused changes in the men’s
blood that “appear to indicate the initial stage of a pathological process such as occurs at the start of a cancerous condition.”  Hertel didn’t actually find that microwaved food caused cancer.  And his “study,” which no researchers have tried to reproduce, was never peer-reviewed or published in a scientific journal.

“People who ingested microwaved foods showed a statistically higher incidence of stomach and intestinal cancers, plus a general degeneration of peripheral cellular tissues and a gradual breakdown of the function of the digestive and excretory systems,” Kopp
wrote.

The Soviet research was never published and the institute where it was conducted, in what is now the Republic of Belarus, no longer exists. (The former Soviet Union may have banned microwave ovens for a short period, but no countries ban them today.)

Foods cooked in microwave ovens are “a recipe for cancer,” adds medical journalist Simon Best on his Electromagnetic Hazard and Therapy Web site (www.em-hazard-therapy.com).   Hertel and Kopp aside, here’s what we know about microwave ovens.

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“A microwave oven heats food using radio waves that are almost identical to radar,” says
Jim Felton of the Lawrence Livermore Radiation Laboratory in Livermore, California.   The frequency used in microwave ovens, about 2,500 megahertz (MHz), is more powerful than the frequency that’s used to transmit radio, television, and cell phone signals. But it’s thousands of times weaker than ultraviolet light, visible light, and X-rays and millions of times weaker than the gamma radiation that’s used to irradiate some foods.

“While X-rays, gamma radiation [though not irradiated food], and even sunlight can cause cancer, microwave radiation cannot because it simply doesn’t pack enough power to damage your DNA,” says Gary Zeman of the Health Physics Society in McLean, Virginia.   The Society is a nonprofit scientific organization that promotes radiation safety.

What 2,500 MHz microwaves can do is get absorbed by the water, fats, and sugars in food. That generates heat, which cooks the food. Once the oven is turned off, it produces no more microwaves. And those that it did produce are long gone.   “The lifetime of microwaves in the oven is something like millionths of a second,” says physicist Louis Bloomfield.

Forget the charges floating around the Internet. The “evidence” that microwaved foods cause cancer boils down to  Hans Hertel’s and William Kopp’s claims.   “There is nothing solid,” says Lawrence Livermore’s Jim Felton, who is also associate director for cancer control at the Cancer Center at the University of California, Davis.    That may explain why scientists haven’t spent time and money looking for a link. “I can honestly tell you that I have never seen a valid scientific study  –  and I pay attention to most of the cooking research out there—that has given us reason to test.

Click to access microwavemyths.pdf

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Chris Deep

Lots of debate on this. Some interesting publications listed below.
Article below is a court case of someone being killed during a routine surgery due to microwave heated blood tranfusion.

So it’s clear there are some very detrimental effects particularly where fluid foods are concerned (milk, etc…) . Most of this seems to come from the uneven heating caused by microwaves rather than the microwaves themselves.
Unlike conventional heating where the source of heat is first applied to the utensil and then to the food, microwaves use the food itself to generate the heat. In conventional heating the utensil is a high thermally conducting material which presents the food with a more even and gradual heat change while with microwaves the heat is applied directly to certain parts of the food while others can remain completely cold because natural convection and conduction don’t have time to act. (Classic example is to try heating a bowl of thick soup).

In the world of fine cuisine utensils of varying thickness, shape and material are used for specific types of food. This is so that the application of heat can be controlled in a certain way depending on the type of food to give it a certain flavour. In microwave cooking the function of the utensil is merely as a holder for the food. The heat always gets applied directly so there is not much control except possibly to turn down the intensity. However most commercial microwaves do not do this! It simply turns the magnetron on and off giving spots of high intensity in the food.

Maybe this calls for the invention of some microwave utensil where the utensil gets heated and then conveys the heat to the food. This would however take away some of the efficiency in power (but you don’t get something for nothing).

So the conclusion as far as I can see is that microwaves although efficient should be used with caution. They are probably not as bad as some articles on the internet would show. Personally I have stopped using microwave ovens altogether for foods of low viscosity and only occasionally for solid and highly viscous foods.
 
 
SOME PUBLICATIONS:
Chemical changes during microwave treatment of milk
Extracorporeal Hemolysis of Blood in a Microwave Blood Warmer
Article Extracorporeal Hemolysis of Blood in a Microwave Blood Warmer
 
 
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Hazim Hashim Tahir
Ministry of Science and Technology, Iraq
Dear Colleagues, Good Day,
“How Your Microwave Oven Damages Your Health In Multiple Ways

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How Microwaves Damage Your Health

You might not be aware of this, but microwave ovens operate on gigahertz frequencies very similar to most 4G cellular networks. So, the danger AND the justifications why are identical. Conventional science and industry are clinging to the concept that these microwaves from your cell phones, portable phones, Wi-Fi routers, smart meters and wireless computers and tablets are not harmful because they do not cause any thermal damage.

New research from Professor Emeritus Martin Pall, Ph.D., has provided us with the mechanism of how this low level nonthermal microwave exposure causes biological harm. It has to do with voltage gated calcium channels (VGCCs) that are embedded in the cell membranes. He determined this by evaluating over two dozen studies showing you can radically reduce biological microwave damage using calcium channel blockers.

This explains why the argument that the microwave radiation is not high enough to cause thermal damage is fatally flawed. The statement is partially correct, as the radiation does not cause thermal damage. However, it causes massive biological damage. Pall has compiled a list of 123 studies and papers documenting the various non-thermal health effects of EMFs for those who want to take a deep-dive into the research. The safety standards that have been established are off by a factor of over 7 million.

So just how does it cause damage? Well, once the VGCCs are activated by microwaves, about 1 million calcium ions per second, these ions then stimulate the release of nitric oxide, which combines with superoxide to form peroxynitrate. These peroxynitrates then create hydroxyl free radicals, the most destructive free radicals known to man, which decimate mitochondrial and nuclear DNA, membranes and proteins that lead to mitochondrial dysfunction, the core of most chronic disease.

Pall has calculated that these VGCCs are over 7 million times more sensitive to microwave radiation than the charged particles inside and outside the cell, which means the currently established safety standards are off by a factor of over 7 MILLION.

Interestingly, the tissues with the highest density of VGCCs are the brain and nerve tissue like the pacemaker in the heart, and also in the testes. This could explain why we are having an exponential increase in many diseases like autism, Alzheimer’s, arrhythmias, anxiety, depression and male infertility. Indeed, in a 2016 paper, Pall documents how microwave EMFs produce “widespread neuropsychiatric effects including depression.”7

Microwave radiation does not have enough energy to directly break covalent bonds and damage your DNA in the way that ionizing radiation from X- or gamma rays do. However, it can actually cause more DNA damage than ionizing radiation as a byproduct of the increased hydroxyl free radical production.

Failure to realize this and take steps to minimize exposure not only will damage your DNA and increase your risk of most chronic illness, but also seriously impair your body’s ability to remove toxins, and significantly impair your immune response to address the large variety of pathogenic infectious assaults you regularly encounter, especially parasites.

It is important to understand that using your microwave oven will expose you to an energy density of milliwatts per square centimeter (the standard energy unit measurement in the U.S.).

While that sounds like a small number that will not cause thermal damage, it is easily thousands if not millions of times higher than the energy density shown to cause biological damage in hundreds of studies, as biological damage typically shows up in the micro to picowatt range.

So, every time you turn on your microwave oven, you are exposing yourself to microwave radiation densities thousands of times higher than your cellphone. This is the primary reason why I strongly advise removing the microwave from your home. Next, I will review some of the evidence showing how microwaves damage your food. But remember, this is a relatively minor issue compared to the DIRECT biological damage it will cause you and your family every time you turn it on. The closer you are to the oven, the higher the energy density and the worse the damage will be.”,…
Please, see the source for more details:
 
 
 
 
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REACTION OF 

 
Hazim Hashim Tahir
Ministry of Science and Technology, Iraq
 
K. Karthik
We would like to know the source of your responses, otherwise it is pure plagiarism. Since you are a PhD holder should know that and you should teach the others the right things!!!
This is the source of your first response:
This is the source of your second response ( same as the first one – it was taken from the bottom part of the article):
This is the source of your third response”
This is the source of your fourth response:
This is the source of your last response ( The author name: Joshua Engel, Enthusiastic eater and adventurous cook .)
 

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Forest Research Institute Dehradun
 
As far as the nutritional value is concerned, it’s true that microwaving does destroy some of the nutrients in food, but any cooking method does that. Any type of heating will destroy some nutrients in food, especially Vitamin C, which is very heat-sensitive.

Evidences either that microwaved food is less nutritious than food cooked by other methods or that the microwaves themselves cause any kind of health problems, are contradictory. I agree with Najib that “one should apply the precautionary principle and avoid it as much as possible.”

 
YOGESH CHANDRA TRIPATHI

Forest Research Institute Dehradun

Microwaves are electromagnetic waves within a frequency band of 300MHz to 300 GHz. and belong to the non-ionising radiations.

Microwaves are not forms of heat, but rather forms of energy that are manifested as heat through their interaction with materials. Microwaves initially excite the outer layers of molecules.


The inner part of the material is warmed as heat travels from the outer layers inward. Most of the moisture is vaporized before leaving the material. In conventional or surface heating, the process time is limited by the rate of the heat flow into the body of the material from the surface as determined by its specific heat, thermal conductivity, density and viscosity. Surface heat is not only slow, but also non-uniform with the surfaces, edges and corners being much hotter than the inside of the material.

Consequently, the quality of conventionally heated materials is variable and frequently inferior to the desired result. Microwaves cause water molecules in food to vibrate, producing heat that cooks the food.

That’s why foods that are high in water content, like fresh vegetables, can be cooked more quickly than other foods. The microwave energy is changed to heat as it is absorbed by food, and does not make food radioactive or contaminated. Microwave cooking can be more energy efficient than conventional cooking because foods cook faster and the energy heats only the food, not the whole oven compartment.

Microwave cooking does not reduce the nutritional value of foods any more than conventional cooking. In fact, foods cooked in a microwave oven may keep more of their vitamins and minerals, because microwave ovens can cook more quickly and without adding water.

 
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The research on microwave ovens reveals the following…

Microwaving prepared meats to ensure sanitary ingestion was found to provoke the formation of d-Nitrosodienthanolamines, a well-known carcinogen.
 
Microwaving milk and cereal grains was found to convert some of their amino acids into carcinogenic substances.
Swiss clinical trials have found that microwaving food increases cholesterol levels. It was also found to decrease red and white blood cell counts while decreasing hemoglobin and producing radiolytic compounds.
 
Thawing frozen fruits was found to convert their glucoside and galactoside containing fractions into carcinogens.
Even very short exposure of raw, cooked, or frozen vegetables to microwaves was found to convert their plant alkaloids into carcinogens.
 
Russian and Japanese studies have shown how food can lose nearly 60% to 90% of its food value when cooked or heated in a microwave oven. Significant portions of Vitamins B, C, E, and essential minerals have been found to be lost.
Food cooked in a microwave oven with a little water can lose up to 97% of its beneficial antioxidants.
 
Another issue with microwave ovens is that many people cook food in plastic and paper containers. Carcinogenic toxins can leach out of this packaging into your food. Studies have shown that chemicals such as polyethylene terpthalate (PET), benzene, toluene, and xylene can leach from the packaging of common microwavable foods such as pizzas, fries, and popcorn.
 
 
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University of Al-Qadisiyah
 
According of my reading I found :. The detrimental effects of microwaves and microwave cooking.

1- study found that broccoli when microwaved with a little bit of water loses up to 97% of its beneficial antioxidants. Steamed broccoli only lost 11% or less. Some amounts of phenolic compounds and glucosinolates were also lost. The study was published in the November 2003 issue of The Journal of the Science of Food and Agriculture.
2- Vitamin C in asparagus spears was lost during a 1999 Scandinavian study.
3-One study found 60 seconds of microwaving garlic depleted the food of it’s allinase, garlic’s primary cancer-fighting ingredient
4- Just 6 minutes of microwave heating turned 30-40 percent of the B12 in milk into a dead form, which was found in a Japanese study by Watanabe.
5- An Australian study recently conducted showed that microwaves cause a higher degree of “protein unfolding” than conventional heating.
6- A 1992 study found that breast milk lost lysozyme activity, antibodies, and became a more suitable environment for the potential growth of pathogenic bacteria after being microwaved

 
 
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Microwave heating is the process in which a high-frequency alternating electric field, or radio wave or microwave electromagnetic radiation heats a dielectric material. At higher frequencies, this heating is caused by molecular dipole rotation within the dielectric materials…As the field alternates, the molecules reverse direction. Rotating molecules push, pull, and collide with other molecules (through electrical forces), distributing the energy to adjacent molecules and atoms in the material. The process of energy transfer from the source to the sample is a form of radiative heating….
 
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Aderonke Abd’Quadri-Abojukoro
 
University of KwaZulu-Natal
Microwave ovens do not make foods radioactive. Microwave ovens heat food by producing radiation which is absorbed by water molecules in the food. This makes the water molecules vibrate and produce heat, which cooks the food. Microwaves heat food. They do not make any changes to food that aren’t made in any other cooking method. So they do not make food any more likely to cause cancer. If you follow the instructions for use for a microwave oven there is no known harmful effect on humans. For more information on radiation emissions from microwave ovens please refer to the Australian Radiation Protection and Nuclear Safety Agency Read more at https://www.cancercouncil.com.au/86089/cancer-information/general-information
 
 
Aderonke Abd’Quadri-Abojukoro
University of KwaZulu-Natal
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. They do not make the food or the oven radioactive. There is some evidence that nutritional content of some foods may be altered differently by cooking in a microwave oven, compared to conventional cooking, but there is no indication of detrimental health issues associated with microwaved food.( https://www.arpansa.gov.au/understanding-radiation)
 
 
 
 

 

Een gedagte oor “Mikrogolf – microwave”

  1. I am an electronic engineer who major in microwave theory and have studied quantum mechanics. Microwave ovens has has no radiation or genetic mutation issues with food or human tissue, nor does it really heat food that much differently than a normal oven. Meaning, both does the same physical thing, heat food. Now its true that IR waves like in normal oven concentrate all energy on the surface while microwaves penetrate about 2 cm into the food, causing different heating profiles. IR from ovens will be absorbed in the first 1mm of the skin of the food, this cause the crispy roast effect. it makes no sense to suggest that microwaves do anything different to food than IR waves. Different heating profiles would cause different foods to heat differently and taste different but temperature is only the vibration of molecules. Both sources get the vibration going on the same basis. Conduction, convection and radiation is present in microwave, fire, oven etc. only frequency and skin depth differs. But if IR do not cause harmful EM waves, then the less energetic microwaves will not either. Heat is heat.
    Food can taste different because of these profile differences, but radiation itself poses no health risk unless you heat the body tissue. But this is not what causes cancer. Biology depends on chemistry, chemistry depends on quantum mechanics and quantum mechanics do not agree with microwaves cause cancer hypothesis simply because microwaves do not change chemistry unless its heat that changes chemistry. But heat do not cause genetic issues else we all would have been dead long ago. The issue is that genetic mutation takes place when chemical change take place in the tissue cell like the cell remains intact and functional, but it cause DNA in the cell to break down.
    In order to succeed, you need to consider what it takes to ionize carbon, phosphorus, oxygen, nitrogen all these elements are nonmetals and would not ionize below 10eV, this is the photon energy you need to kick the lowest excitation energy electron through the Fermi energy gap, the problem with the microwave cause cancer theory in quantum mechanics is, that microwave photons are about 10 micro eV, you need a million times more energy to kick any element of DNAs electron out of the atom to change a chemical bond to change the gene. You will not cause a cancerous mutation unless you can pull that off, and you need about a million times more energy not dissipated, but packed into one photon. for that you need the higher part of the UVc spectrum.
    At microwave photon levels you cannot excite an electron enough to make the jump. Microwave has even less energy than IR waves your oven use, but none of them can penetrate the content of a cell without destroying the entire cell. Destroyed cell (burned cell) do not mutate, because it is destroyed. for mutation you need to knock the DNA and keep the cell intact. Microwaves, IR, visible light will not get it right, if anything with high power density will make an effect, it would heat and burn the material to a crisp but not cause genetic mutation. Bottom line, microwave ovens are perfectly safe, unless you place it somewhere where it can drop on your head.

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