Magnets are everywhere, and almost all machinery and electronic devices use magnetic accessories, so magnetic fields have long been an integral part of the modern world. However, anyone with a little medical knowledge will know that the human body contains iron, especially in the blood. This raises a number of questions, for example, the human body is often exposed to magnetic fields every day, so will the iron in the blood be sucked away by the magnetic field? Can magnetic fields damage a person's health? Or even, will a particularly strong magnetic field bring a person's life in danger?
Interesting experiments
In order to study these issues, scientists have done a set of interesting experiments, and the experimental results are somewhat surprising.
In the first experiment, scientists used the addition of red pigment water and plastic tubes, the red water from the upper end of the plastic tube injection, the lower end out, so that the red water flow to simulate the flow of blood in the human blood vessels. Next to the plastic tube, the scientists placed a magnet to observe the magnetic field on the simulation of "blood vessels" what effect. The results found that when the red water does not contain iron, the magnetic field will not have any effect on its flow; but if you add iron filings to the red water, then after the magnetic field, the iron filings in the plastic tube will gather near the magnet, forming an embolism, blocking the "blood vessels.
Obviously, if the body contains iron filings, then the magnetic field will cause the body's blood vessels to clog, endangering lives. Fortunately, however, the iron in our blood is not simple iron in the form of iron filings, but is part of hemoglobin, which is responsible for the red color of the blood, transporting oxygen from the lungs to the body's cells, and carrying away the carbon dioxide produced by the cells.
How much iron is contained in hemoglobin? Structurally speaking, hemoglobin is a very complex macromolecule. To make a simple comparison, blood contains about 50% water, and a water molecule is composed of only two hydrogen atoms and one oxygen atom. Hemoglobin, on the other hand, is different in that its molecule consists of 2952 carbon atoms, 4664 hydrogen atoms, 832 oxygen atoms, 812 nitrogen atoms, and 8 sulfur atoms and 4 iron atoms.
There are only 4 iron atoms? Yes. As you can see, the amount of iron in human blood is not particularly high either. The blood will not react to a magnetic field of normal strength. So, the scientists designed a second experiment. They used thick pig blood instead of human blood, it will be held in a lightweight Styrofoam container, and then let the Styrofoam container floating on the surface of the still water, and then with a super strong magnetic force of the giant magnet to close to the container. As the foam floats on the smooth water surface, there is no friction, so even if it is subject to weak magnetic force, it will also drift on the water surface. What would the results of the experiment be? Contrary to what one might expect, pig blood and magnets surprisingly repel each other.
Why is blood anti-magnetic?
Blood and magnets repel each other, scientists call this phenomenon "anti-magnetic reaction". Since human blood contains iron, why is it antimagnetic? In fact, magnetism is closely related to the structure of atoms.
Simply put, magnetism originates from the movement of electric charges, which is the reason why an energized conductor (such as a solenoid) can generate a magnetic field. In an atom, electrons, through their spin motion, can produce a microscopic magnetic field. Although the protons and neutrons in the nucleus also have their own magnetic fields, they are much weaker than those produced by electrons, and overall, the magnetic field of an atom will be determined by the magnetic field of the electrons. According to quantum mechanics, the electrons in an atom exist in "pairs", and the electrons that are paired with each other will have opposite spins, which will cancel each other's magnetic fields. Only when there are unpaired electrons in an atom or crystal structure does it show a net magnetic field. Therefore, by counting the number of unpaired electrons in a substance, scientists can determine its magnetic response.
In the case of a single iron substance, for example, each iron atom in the iron filings has four unpaired electrons in its outermost layer, which causes the individual iron atom to show a strong magnetic field. In the presence of an external magnetic field, the direction of the magnetic field of the individual iron atoms "follows" the direction of the external magnetic field, so that the iron atoms are paramagnetic.
For hemoglobin, the situation is much more complicated. Scientists have found that in hemoglobin, the number of unpaired electrons in an iron atom depends on the degree of oxidation of the hemoglobin. For example, each iron atom in deoxyhemoglobin (i.e., hemoglobin that does not carry oxygen) has four unpaired electrons, making deoxyhemoglobin weakly paramagnetic; but the iron atoms in oxyhemoglobin (i.e., hemoglobin that carries oxygen) have no unpaired electrons, making oxyhemoglobin antimagnetic. In arterial blood, oxyhemoglobin accounts for more than 96%, and in venous blood, oxyhemoglobin accounts for 60% to 80%. It is evident that most of the hemoglobin in blood is antimagnetic, and that the water that makes up half of the components is also antimagnetic. Therefore, as much as hemoglobin contains iron, blood is repulsive to magnetic fields.
Safe daily magnetic fields
Whether paramagnetic or antimagnetic, magnetic fields have an effect on blood. But don't worry, because the magnetic fields that humans are exposed to in daily life are too weak to affect human health.
We know that in physics, the unit used to measure the strength of the magnetic field is called gauss, and the larger unit is the tesla, 1 tesla is equivalent to 10,000 gauss. The strength of the magnetic field on the earth's surface is only 0.25 to 6.6 gauss, which can only affect pigeons and help them find their way home. The magnets used in refrigerators have about 50 gauss, and electric guitar pickups have about 100 gauss.
The most powerful magnetic field to which the average person has access is the magnetic resonance imaging (MRI) technology occasionally used in medical examinations or medicine. MRI scanners use superconducting magnets that can generate powerful magnetic fields of 15,000 to 94,000 gauss. A magnetic field of this magnitude can cause the only protons in the nucleus of a hydrogen atom to vibrate, causing the latter to emit radio waves that can be read by the instrument. For the average person, MRI is safe, unless you have a metal implant in your body, and that's what causes the danger - any metal implant will be pulled violently by the magnetic field during an MRI, causing you great damage.
What if you eat a lot of iron-containing food, or some bad guy injects you with some iron? Then the iron will be broken down quickly in the intestines so that it can be absorbed by the body and then become very scattered so that the iron levels remain low. For example, the iron in cereal can even remain ferromagnetic, but even though it's still in your stomach, it won't be vibrated up by the magnetic field of an MRI instrument. So if you ingest or inject enough iron, instead of worrying about magnetic fields, you should be more wary of metal poisoning.
The Terrible Magnetar
So, is there a magnetic field in nature that is powerful enough to kill you? The answer is yes. But you have to go on an interstellar trip to see the power of this magnetic field.
In the vastness of space, when a large star has 1.5 to 3 times the mass of the Sun, it will experience a war between nuclear fusion and gravity, and in the end, gravity will win. After a huge explosion called a supernova, all the matter will be so tightly bound together by gravity that most of the electrons will be pulled into the protons and combine to form neutrons, forming objects we call neutron stars. Neutron stars are more massive than the Sun and even more dense - a teaspoon of neutron stars would have a mass of more than a billion tons. Neutron stars typically spin at hundreds of revolutions per second, and protons and electrons form electrical currents around the fast-spinning neutron star, creating a powerful magnetic field of trillions of gauss. This is enough to disrupt the chemical reactions and synapses that occur in your body and take your life.
Finally, let's talk about a very interesting object - the magnetar. About one in ten neutron stars has enough surface current and spin speed to give it a magnetic field of up to 4 trillion gauss, and such a neutron star is a magnetar. The closest magnetar to Earth is called "AXP1E1048-59", which is about 9,000 light years away. If you get close enough, say a few hundred kilometers - assuming you have not been killed by cosmic rays at this point - the powerful magnetic field generated by this magnetar will pull the electrons out of your body and break the molecular bonds in your cells, pulling your atoms out one by one, and you will turn into a wisp of "smoke You will become a "smoke", spiraling towards this supermassive magnetar and eventually become a part of it.
So, on Earth, humans will not be harmed by magnetic fields, but if they want to explore space, then in addition to cosmic rays and vacuum, humans need to be alert to the threat of magnetic fields.
