I was under the impression that most people have at least a basic understanding of radiation. It looks like I was sadly wrong, though I suppose the necessity of a YouTube video explaining what radiation is in the first place should have been a dead giveaway. Yesterday I wrote a blog post on why saying that GMOs are carcinogens is just plain wrong. Well, today one of anti-GMO people in the YouTube discussion asked if GMOs are tested for radiation. This displays an extreme lack of understanding of radiation and a disturbing lack of willingness to spend 5 minutes Googling something to get even the most basic information before making rather absurd claims about it. So, for those who actually care about being right, it is time for a discussion on radiation.
The simple answer to the question "Are GMOs radioactive?" is no. The reaction you are likely to get from pretty much any scientist who knows anything about radiation, when you ask this question is, "Wait, what the heck are you talking about?"
The long answer starts with the question: How do things become radioactive? First though, perhaps we should look at what radiation is in the first place.
Technically, radiation is any kind of electromagnetic energy that that is moving through space. This includes things like radio waves, visible light, certain forms of heat, as well as UV from the sun, x-rays, and gamma rays. It also traditionally includes certain other types of particles flung through space at extremely high speeds. When people talk about dangerous radiation, they are usually talking about a few specific kinds. There are three kinds of radiation that are generally emitted by radioactive particles. Alpha radiation is the least dangerous, at least in most circumstances. Alpha radiation is when a radioactive atom ejects two protons bound together as helium, at extremely high speeds. This helium nucleus has enough energy to do a great deal of damage, but it is not generally dangerous to humans, because it cannot penetrate the skin. Ingested, however, it could do substantial damage. The second type of radiation is beta radiation, which is just an electron or positron ejected at high speed. This is generally considered more dangerous, because it can penetrate skin, but it generally does less damage than alpha radiation. If a beta decay produces a positron, however, when the positron meets with an electron, they will destroy each other, potentially releasing more dangerous radiation. The last type of radiation is gamma radiation. This is just a form of electromagnetic radiation (much like radio waves or visible light), except that it carries far more energy. Gamma radiation is considered the most dangerous form of radiation, because it can penetrate all the way through the body easily, and it can damage DNA, potentially causing cancer. Keep in mind though, it takes a lot of radiation of any kind to do significant damage. One or two or even a few hundred atoms won't do enough damage to detect.
One more thing that is important to keep in mind is that gamma radiation is not some rare thing that we only see from radioactive substances. Stars and black holes that are many of light years away are producing large amounts of gamma radiation, and very small amounts of that are constantly passing through Earth and through us. There are also other kinds of less well understood radiation in the form of energetic particles from space, called cosmic radiation, that can occasionally interact with DNA, also potentially causing cancer. There is no way to prevent this, though, so we don't generally worry to much about it, and there really is not that much reaching Earth. Most cases of cancer are due to either consuming non-radioactive carcinogens or just normal random mistakes that occur in cells all the time.
So now that we know more about radiation, how do things become radioactive? Just like calling an object carcinogenic, technically calling an object radioactive is wrong. Atoms are radioactive. It is common to call objects containing large numbers of radioactive atoms radioactive though. How does an atom become radioactive? It is complicated, and it requires a lot of energy. One of the simplest radioactive atoms is hydrogen-3, also known as tritium, and it is used in hydrogen bombs. The thing that makes it unique is that it has 2 neutrons and only 1 proton, and having significantly more neutrons (twice as many, here) than protons makes atoms unstable (too few neutrons can also cause instability). It decays into helium-2 (which is stable; that means it is not radioactive) via beta decay, emitting an electron and an electron anti-neutrino (which we won't worry about, because it does not interact much with ordinary matter). Most hydrogen-3 is produced in nuclear reactors, but it can also be extracted from sea water. It is not very common, but it is constantly being produced in oceans when hydrogen in water is hit by certain kinds of cosmic radiation, adding a neutron to the more common hydrogen-2 (which has 1 neutron). In nuclear reactors it is produced the same way, by radiation (usually energetic neutrons) that is emitted from the nuclear reactions that produce energy used to generate electricity. Tritium is safe enough that it is used to make glow-in-the-dark key chains in many places in the world (this is illegal in the U.S., not for safety reasons, but because tritium is also used in hydrogen bombs). More dangerous radioactive elements are generally heavy elements, which are primarily produced in super novas of stars. Regular stars cannot create elements heavier than about iron. Not all heavy elements are naturally radioactive, though a few have radioactive isotopes (an isotope is defined by its number of neutrons, so hydrogen-3 is a different isotope of hydrogen from hydrogen-2). In nature, radioactive elements tend to decay until they become stable elements (or isotopes), but some take millions of years to do this. Uranium is probably one of the most well known radioactive elements, but Radium was one of the first discovered. Radioactive elements can be created in labs, but it takes enormous amounts of energy. Naturally occurring radioactive elements are rare, but they can be found in some places. What it comes down to though is that radioactive elements require huge amounts of energy to make, and they can only be made in large quantities in nuclear reactors and exploding stars.
What about GMOs? How could they become radioactive? The uneducated masses that claim GMOs are radioactive seem to believe that GMOs just magically become radioactive, because they are GMOs. This is completely false. Changing an organisms DNA will not make that organism suddenly radioactive. Some may believe that GMOs can produce radioactive substances, but given the energy required for humans to deliberately make them, it seems incredibly unlikely. Further though, we have never observed an organism that could do this, and if we had, we would certainly be using it to make reactor fuel or even to turn lead to gold. If messing with atoms was that easy, alchemists would have figured this one out hundreds of years ago. In addition, the amount of energy required for a plant to create significant amounts of radioactive atoms is more than any plant has ever collected (even those ancient Redwoods in California would fail this one). The fact is, it is practically impossible. The last problem with GMOs producing radioactive atoms is that if they produced enough to be harmful to humans, they would destroy themselves long before they were ready to harvest. It is just not feasible to claim that GMOs can create radioactive atoms.
If GMOs cannot create radioactive atoms though, perhaps there are other ways they could acquire them. This is true, there are other ways. The most likely way would be for humans to deliberately put them there, but there is no reason for any for-profit company to deliberately kill off their paying customers, and besides, it would be extremely expensive to put enough in to be dangerous. Is it possible it could be happening accidentally? No here too. Modern genetic modification processes work by taking genes (which are just sections of DNA; no radioactive atoms there) from a donor plant and inserting them into the subject plant. This process does not involved enough energy to make radioactive atoms, and it does not involve the use of any radioactive materials, so there is no chance for the resulting GMOs to be radioactive. What about the old technique of bombarding cells with radiation to cause random mutations? This technique probably could create radioactive isotopes, depending on the type of radiation used, but there is no way it could produce more than a very small amount. The problem we have here is that radiation kills things in large amounts, and if you are merely trying to mutate a cell by modifying its DNA you really don't want to kill it. The odds of making more than a few radioactive atoms doing this is extremely low. In fact, it is so low that many companies use irradiation to sterilize chicken eggs before sending them to the retail stores (this is enough radiation to kill stuff, since the goal is to kill bacteria). If there are not enough radioactive atoms in those to be harmful, there certainly won't be in a few plant cells or even a whole seed. Even if there was though, unless the plant is producing radioactive atoms (which it cannot), any radioactive atoms will almost certainly not end up in the edible part of the plant, and _even if they did,_ they would be so diluted that there would not be enough to be dangerous.
There is one other way GMO plants could acquire radioactive atoms, but it is not unique to GMOs. If there are already radioactive isotopes of atoms that are normally absorbed by a plant in the soil it is growing in, then that plant would very likely absorb those atoms along with the non-radioactive isotopes of it. It does not matter if a plant is GMO or not for this to occur though; it will happen with any kind of plant. In theory, this could result in food that is radioactive enough to be harmful, but there is still one problem. If the plant absorbs enough radioactive atoms to harm a human, the radiation will also harm the plant, and probably far more severely than a human. Radiation does its damage in several ways, but the most dangerous is by damaging DNA. This is nothing like adding a gene to a cell though. Radiation has a lot of energy, which means that it could heat a very small part of a strand of DNA, causing a break that prevents it from being read properly. This would likely result in mutant proteins being created, which could tell a cell to multiply uncontrollably, resulting in cancer. Thankfully, most DNA damage just results in the death of the cell, eliminating any further potential for damage. High concentrations of radiation don't just damage DNA though. It can kill a lot of cells, which is what causes radiation sickness. Now, think about a corn plant. It has a lot less mass than a person. So a safe amount of radiation for a person could harm a corn plant. Enough radiation to cause significant harm to a person would harm the corn plant even more, and since plant cells generally divide a lot faster than human cells, the effect would be further amplified (because the damaged DNA is reproduced more). In other words, enough radiation to seriously harm a human would almost certainly kill the corn plant long before it produced any corn. Even if it didn't though, the severe DNA damage would probably mutate the corn plant enough that it would be extremely obvious that something is very wrong with it.
What it all comes down to is that even the old method of genetic modification does not make something radioactive enough to have any more impact than naturally occurring radiation coming from the stars and from space. Plants cannot make radioactive atoms. If plants were picking up radioactive atoms from their farm lands (it would not matter if they would GMO plants or not), if it were amounts harmful to humans, it would kill or otherwise destroy the plants before any food was produced. And even if a for-profit company was stupid enough to make their GMO seeds radioactive, most of the radioactive atoms would be left in the roots and lower stem of the plant, and anything that did get to the edible part would emit less dangerous radiation than the sky (from stars and blackholes and such).
Like I said, the short answer is no, GMOs are not radioactive.
25 August 2016
24 August 2016
Are GMOs carcinogenic?
In a recent debate in the comments of a YouTube video, I discovered something that is somewhat disturbing: A vast majority of people who claim that GMOs are carcinogenic don't actually know what "carcinogenic" means, and the evidence seems to indicate that they also don't know what "GMO" means either. This includes at least one person who claims to have a degree in biology with a basic understanding of genetics (a claim that I do not believe). Perhaps if I explain what these terms mean, it will help people to understand why it is absurd to claim that GMOs are carcinogenic.
The start with, what is a GMO? Based on my experience, most lay people believe that a GMO is some kind of molecule or other thing that can be in their food. GMO actually stands for Genetically Modified Organism. An organism is something alive, like a plant, an animal, a bacteria, or pretty much anything else that is alive. When we talk about GMOs in the context of food, we are generally talking about plants. So ,GMO corns does not have GMOs in it, it is a GMO. A GMO is merely an organism that has had its DNA changed in some way. When we talk about GMO plants, we are generally talking about plants that had their DNA changed deliberately and directly by humans, but technically every plant, animal, and other living creature on Earth has arisen from millions of years of natural genetic modification, and a vast majority of the plants and animals that humans eat have had their genes deliberately changed though selective breeding. Every GMO is just a regular organism that has had its DNA changed in some way that could have also happened naturally given the right conditions.
Creating GMOs is a complex process that does something simple. There are several techniques for doing it, but there is one modern technique that is used for making pretty much all GMO food plants. This technique starts by taking a plant with a specific desired trait and experimenting to figure out what gene in that plant causes the desired trait. The most well known trait used in GMOs is resistance to a specific herbicide. Another valuable trait might be more efficient nutrient use, which would be helpful in places with poor soil. Once the gene is isolated, it is removed from the plant and injected into the cells of a plant that genetic engineers want to give the trait. Genes can do a number of different things, but the most well known things genes can do is create proteins. So a gene that makes a plant pesticide resistant might create proteins that break down the molecules of the pesticide before it can damage cells. While it is theoretically possible that a gene from a plant could produce something that is toxic to humans, it is incredibly unlikely if that gene was taken from a plant that does not already product toxins that affect humans.
Now we should make sure we understand what "carcinogenic" actually means. Google defines it as "having the potential to cause cancer." It defines "carcinogen" as "a substance capable of causing cancer in living tissue." Essentially, a carcinogen is a chemical compound or element that can pass into a cell membrane and damage the DNA inside the cell in ways that cause the cell to become cancerous.
So, what about GMOs being carcinogenic? The first think to keep in mind is that technically carcinogens are compounds. Compounds are molecules made up of atoms. There are also a few carcinogenic elements, but they are rare in nature, so you don't generally find them without looking. Nothing larger than a molecule can technically be carcinogenic itself, though we typically refer to objects containing carcinogenic molecules as carcinogenic themselves. Technically though, it is not the tobacco itself that is carcinogenic, but rather it is the nicotine molecules (and a few other things) that are in the plant that are carcinogenic. In theory, we could breed a strain of tobacco without nicotine (and the other things), and it would still be tobacco, but it would not be carcinogenic, because it does not contain any carcinogens.
Now, this brings us to GMOs. The only way we can call GMOs carcinogenic is if they contain carcinogenic molecules. Non-GMO corn does not contain any carcinogens, so it is not carcinogenic. GMO corn cannot be inherently carcinogenic, because the genes we added are not carcinogenic (genes are just short pieces of DNA, and DNA is not carcinogenic, so genes cannot be). What about the plant that we took the genes from, when we made the GMO corn? Honestly, I cannot say, because I don't know what that plant was, but it is very unlikely any company would risk getting fined or shut down for knowingly taking such a risk, and since most plants don't contain carcinogens, it is safe to assume that if plants resistant to a particular herbicide exist, there are probably plenty of non-carcinogenic options. (Keep in mind, these companies want your money, and if you die from cancer because their product is carcinogenic, they are not going to make as much money from you.) Additionally, if a gene that is known to make a plant herbicide resistant is put into a non-carcinogenic plant, even if the original plant did produce carcinogenic compounds, the new GMO plant is extremely unlikely to produce carcinogens, because the genes that caused the original plant to produce them were not put into the new plant. In fact, because most carcinogenic compounds produced by plants are fairly complex molecules, it is almost certain they are produced by a chain of processes, and reproducing the entire chain of processes in another plant would likely require a lot more than just one or two genes. Making a non-carcinogenic plant produce carcinogens using genetic engineering would require deliberately doing lots of very expensive experiments to isolate all of potentially hundreds of genes involved in the process of producing that carcinogen, and there is no reason any for-profit company would spend that much money just to kill off its own customers.
To take this one step further though, there are a few processes that are far more likely to produce carcinogenic plants. The first one produced pretty much every carcinogenic plant known to man, and that process is natural selection. Tobacco was not invented by humans. It evolved the ability to produce nicotine though natural selection (though humans did use selective breeding to increase its nicotine production, but Native Americans were smoking it in religious rituals long before that). The second one, which is linked to natural selection, is radiation exposure, which can "damage" DNA. This damage modifies the DNA in a much less predictable way than modern genetic modification techniques (and was actually used in early genetic engineering study). This could cause a plant to produce carcinogens, but it would likely take hundreds or thousands of specific modification events for this to happen (and this is probably how tobacco evolved the ability to produce nicotine, over millions of years). Given that a vast majority of plants on Earth don't produce carcinogens though (over millions of years of chances), it seems that the probability of millions of years of cosmic radiation resulting in a carcinogenic plant is also incredibly small. Another process that is more likely to create a carcinogenic plant than genetic engineering is selective breeding. Just the process of reproduction is rife with potential error. Genes can get damaged, split and put back together wrong, or just end up with a bad combination. This could create carcinogenic plants from non-carcinogenic plants, but again, after millions of years of evolution and thousands of years of deliberate selective breeding by humans, you would expect to see at least one food crop that produces carcinogens if this was at all likely. So far, the only carcinogenic plants bred by humans appear to be the ones that we deliberately bred to produce carcinogens (like tobacco), and even those seem to have been made carcinogenic by nature long before humans discovered them.
What it comes down to is that GMOs are not inherently carcinogenic, and the modern processes used to make them would require deliberately spending millions of dollars and many years of work to make them carcinogenic. No one with those resources is going to go to that much effort, especially not for-profit companies that have a vested interest in the survival of their customers. Monsanto might be unethical, but they are not stupid.
Lastly, the FDA mandates that all GMOs be carefully tested for carcinogens. They are also tested for other toxic compounds, though those are just as unlikely as carcinogenic compounds if both plants are not already toxic. Note that the FDA does not require this testing for non-GMO plants, including plants produced using selective breeding, which means that there are good odds that GMO plants are actually safer than non-GMO plants.
If you want to stick to buying non-GMO foods because you don't want to support Monsanto and the way they abuse gene patents, fine. That is a real thing, though perhaps not as bad as it used to be. If you are buying into the claims that GMOs are carcinogenic or otherwise toxic though, you are wasting your money. The only way any plant can be carcinogenic is if that plant produces carcinogenic compounds, and there is no evidence that any GMO does that, the probability of a GMO doing that without someone spending tons of money to make it do that on purpose is almost nothing, and even if they did, the mandatory and extensive testing required by the FDA would have found problems long before now. The fact is, GMOs are not carcinogenic, and not even one carcinogenic GMO has been produced. Don't waste your money on GMOs for your health, because it won't make any difference. If you want to buy GMOs, do it because you don't want to support unethical companies, because otherwise you are not helping anyone.
(I should add, supposedly there is evidence that glyphosate, the compound used in Monsanto's Roundup herbicide that the Roundup Ready line of GMO crops is used with, may be carcinogenic. This does not make the crops carcinogenic themselves, though trace amounts of herbicide remaining on the crops could be hazardous. It is important to realize that this is still better than the seriously toxic herbicides that were used before Roundup replaced them. The best solution to this potential problem, however, is not to buy non-GMO foods that have probably been covered in those more dangerous herbicides. The best solution is to wash your produce before eating it, something that has been recommended for over a century.)
The start with, what is a GMO? Based on my experience, most lay people believe that a GMO is some kind of molecule or other thing that can be in their food. GMO actually stands for Genetically Modified Organism. An organism is something alive, like a plant, an animal, a bacteria, or pretty much anything else that is alive. When we talk about GMOs in the context of food, we are generally talking about plants. So ,GMO corns does not have GMOs in it, it is a GMO. A GMO is merely an organism that has had its DNA changed in some way. When we talk about GMO plants, we are generally talking about plants that had their DNA changed deliberately and directly by humans, but technically every plant, animal, and other living creature on Earth has arisen from millions of years of natural genetic modification, and a vast majority of the plants and animals that humans eat have had their genes deliberately changed though selective breeding. Every GMO is just a regular organism that has had its DNA changed in some way that could have also happened naturally given the right conditions.
Creating GMOs is a complex process that does something simple. There are several techniques for doing it, but there is one modern technique that is used for making pretty much all GMO food plants. This technique starts by taking a plant with a specific desired trait and experimenting to figure out what gene in that plant causes the desired trait. The most well known trait used in GMOs is resistance to a specific herbicide. Another valuable trait might be more efficient nutrient use, which would be helpful in places with poor soil. Once the gene is isolated, it is removed from the plant and injected into the cells of a plant that genetic engineers want to give the trait. Genes can do a number of different things, but the most well known things genes can do is create proteins. So a gene that makes a plant pesticide resistant might create proteins that break down the molecules of the pesticide before it can damage cells. While it is theoretically possible that a gene from a plant could produce something that is toxic to humans, it is incredibly unlikely if that gene was taken from a plant that does not already product toxins that affect humans.
Now we should make sure we understand what "carcinogenic" actually means. Google defines it as "having the potential to cause cancer." It defines "carcinogen" as "a substance capable of causing cancer in living tissue." Essentially, a carcinogen is a chemical compound or element that can pass into a cell membrane and damage the DNA inside the cell in ways that cause the cell to become cancerous.
So, what about GMOs being carcinogenic? The first think to keep in mind is that technically carcinogens are compounds. Compounds are molecules made up of atoms. There are also a few carcinogenic elements, but they are rare in nature, so you don't generally find them without looking. Nothing larger than a molecule can technically be carcinogenic itself, though we typically refer to objects containing carcinogenic molecules as carcinogenic themselves. Technically though, it is not the tobacco itself that is carcinogenic, but rather it is the nicotine molecules (and a few other things) that are in the plant that are carcinogenic. In theory, we could breed a strain of tobacco without nicotine (and the other things), and it would still be tobacco, but it would not be carcinogenic, because it does not contain any carcinogens.
Now, this brings us to GMOs. The only way we can call GMOs carcinogenic is if they contain carcinogenic molecules. Non-GMO corn does not contain any carcinogens, so it is not carcinogenic. GMO corn cannot be inherently carcinogenic, because the genes we added are not carcinogenic (genes are just short pieces of DNA, and DNA is not carcinogenic, so genes cannot be). What about the plant that we took the genes from, when we made the GMO corn? Honestly, I cannot say, because I don't know what that plant was, but it is very unlikely any company would risk getting fined or shut down for knowingly taking such a risk, and since most plants don't contain carcinogens, it is safe to assume that if plants resistant to a particular herbicide exist, there are probably plenty of non-carcinogenic options. (Keep in mind, these companies want your money, and if you die from cancer because their product is carcinogenic, they are not going to make as much money from you.) Additionally, if a gene that is known to make a plant herbicide resistant is put into a non-carcinogenic plant, even if the original plant did produce carcinogenic compounds, the new GMO plant is extremely unlikely to produce carcinogens, because the genes that caused the original plant to produce them were not put into the new plant. In fact, because most carcinogenic compounds produced by plants are fairly complex molecules, it is almost certain they are produced by a chain of processes, and reproducing the entire chain of processes in another plant would likely require a lot more than just one or two genes. Making a non-carcinogenic plant produce carcinogens using genetic engineering would require deliberately doing lots of very expensive experiments to isolate all of potentially hundreds of genes involved in the process of producing that carcinogen, and there is no reason any for-profit company would spend that much money just to kill off its own customers.
To take this one step further though, there are a few processes that are far more likely to produce carcinogenic plants. The first one produced pretty much every carcinogenic plant known to man, and that process is natural selection. Tobacco was not invented by humans. It evolved the ability to produce nicotine though natural selection (though humans did use selective breeding to increase its nicotine production, but Native Americans were smoking it in religious rituals long before that). The second one, which is linked to natural selection, is radiation exposure, which can "damage" DNA. This damage modifies the DNA in a much less predictable way than modern genetic modification techniques (and was actually used in early genetic engineering study). This could cause a plant to produce carcinogens, but it would likely take hundreds or thousands of specific modification events for this to happen (and this is probably how tobacco evolved the ability to produce nicotine, over millions of years). Given that a vast majority of plants on Earth don't produce carcinogens though (over millions of years of chances), it seems that the probability of millions of years of cosmic radiation resulting in a carcinogenic plant is also incredibly small. Another process that is more likely to create a carcinogenic plant than genetic engineering is selective breeding. Just the process of reproduction is rife with potential error. Genes can get damaged, split and put back together wrong, or just end up with a bad combination. This could create carcinogenic plants from non-carcinogenic plants, but again, after millions of years of evolution and thousands of years of deliberate selective breeding by humans, you would expect to see at least one food crop that produces carcinogens if this was at all likely. So far, the only carcinogenic plants bred by humans appear to be the ones that we deliberately bred to produce carcinogens (like tobacco), and even those seem to have been made carcinogenic by nature long before humans discovered them.
What it comes down to is that GMOs are not inherently carcinogenic, and the modern processes used to make them would require deliberately spending millions of dollars and many years of work to make them carcinogenic. No one with those resources is going to go to that much effort, especially not for-profit companies that have a vested interest in the survival of their customers. Monsanto might be unethical, but they are not stupid.
Lastly, the FDA mandates that all GMOs be carefully tested for carcinogens. They are also tested for other toxic compounds, though those are just as unlikely as carcinogenic compounds if both plants are not already toxic. Note that the FDA does not require this testing for non-GMO plants, including plants produced using selective breeding, which means that there are good odds that GMO plants are actually safer than non-GMO plants.
If you want to stick to buying non-GMO foods because you don't want to support Monsanto and the way they abuse gene patents, fine. That is a real thing, though perhaps not as bad as it used to be. If you are buying into the claims that GMOs are carcinogenic or otherwise toxic though, you are wasting your money. The only way any plant can be carcinogenic is if that plant produces carcinogenic compounds, and there is no evidence that any GMO does that, the probability of a GMO doing that without someone spending tons of money to make it do that on purpose is almost nothing, and even if they did, the mandatory and extensive testing required by the FDA would have found problems long before now. The fact is, GMOs are not carcinogenic, and not even one carcinogenic GMO has been produced. Don't waste your money on GMOs for your health, because it won't make any difference. If you want to buy GMOs, do it because you don't want to support unethical companies, because otherwise you are not helping anyone.
(I should add, supposedly there is evidence that glyphosate, the compound used in Monsanto's Roundup herbicide that the Roundup Ready line of GMO crops is used with, may be carcinogenic. This does not make the crops carcinogenic themselves, though trace amounts of herbicide remaining on the crops could be hazardous. It is important to realize that this is still better than the seriously toxic herbicides that were used before Roundup replaced them. The best solution to this potential problem, however, is not to buy non-GMO foods that have probably been covered in those more dangerous herbicides. The best solution is to wash your produce before eating it, something that has been recommended for over a century.)
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