What harm does radiation do to human body?

The influence of radiation on human body begins with cells. It will accelerate the decline of cells, inhibit the formation of new cells, or cause cell malformation, or cause changes in biochemical reactions in the human body. When the radiation dose is low, the human body itself has the ability to repair radiation damage, and can repair the above reactions without showing harmful effects or symptoms. However, if the dose is too high, which exceeds the repair ability of various organs or tissues of the human body, it will cause local or systemic lesions. The following table shows the biological effects of radiation recognized internationally at present. It can be seen that the human body can tolerate the concentrated irradiation of 25 rem without being damaged. Of course, everyone's resistance and physique are different. The possible effect of total body irradiation dose is 0-0.25 Sv, and there is no obvious damage. 0.25-0.50 Sv can cause blood changes, but there is no serious damage. 0.50- 1.0 Sv has some changes and some damage, but there is no fatigue. 1.0-2.0 Sv is harmful, and you may feel weak all over, and 2.0-4.0 Sv is harmful. Weak people may die of 4.0 volts, 50% fatal injuries, and above 6.0 volts may die. When it comes to radiation around us, people are a little scared, because they can't see or touch it, but it will do harm to the human body. In fact, radiation is not uncommon. Radiation is everywhere around us. In our daily life, we are exposed to certain radiation when basking in the sun, watching TV, wearing night-vision goggles, flying and taking X-rays. It's just that the radiation in life is trace and won't cause harm to human body, so people don't feel its existence. Moreover, a large amount of radiation is very harmful to human body, so we should take some corresponding protective measures to prevent and reduce the harm of radiation to our human body. Natural background radiation radioactivity is everywhere in nature, and we have been receiving natural background radiation. The "background" of natural radiation comes from two sources: one is the radiation in the form of high-energy particles, which comes from outer space and is collectively called cosmic rays; Another source is natural radioactivity, that is, radioactive radiation that naturally exists in ordinary substances (such as air, water, soil and rocks, and even food). In addition, people in modern society will be exposed to all kinds of artificial radiation, such as X-ray examination, watching TV and using microwave ovens. The following table lists all kinds of background radiation according to the radiation size. It can be seen that human beings will be exposed to a small amount of radioactive radiation when they eat, use, live and walk. Radioactive sources live around the nuclear power plant for about 0.0002 mSv every year, fly for about 0.005 mSv every hour, watch 1 hour TV every day, eat about 0.00 1 mSv every year, eat about 0.02 mSv of cosmic rays every year, smoke 20 cigarettes every day, and have an annual X-ray examination of about 0.038. The occupational dose limit for radioactive workers is 50 milliSewart per year. The natural radiation in the highest background area in the world is 65,438+0.20 msv per year. The Indoor Environmental Monitoring Center of China Interior Decoration Association recently issued an environmental warning: when buying a house, we must pay attention to whether the electromagnetic radiation pollution in the community exceeds the standard. At present, many citizens have reported that the electromagnetic radiation pollution in their newly-built residential areas is very serious, and not only the electrical appliances at home are disturbed and cannot be used normally, but many people have different degrees of discomfort. With the large-scale urban transformation and real estate development, some power transmission and transformation centers and high-voltage lines originally built around the city have also begun to be developed and constructed, and the electromagnetic radiation pollution problems in the living environment and indoor environment have also followed. These electromagnetic radiations are harmful to human body in six aspects. 1 may be one of the causes of childhood leukemia. Medical research has proved that long-term exposure to high electromagnetic radiation will change blood, lymph and cell protoplasm. According to the research of Italian experts, more than 400 children in this country suffer from leukemia every year. The main reason is that they are too close to high-voltage power lines, which leads to serious electromagnetic pollution. 2. It can induce cancer and accelerate the proliferation of cancer cells in human body. Electromagnetic radiation pollution will affect the circulatory system, immunity, reproduction and metabolic functions of human body, and even induce cancer in severe cases, accelerating the proliferation of cancer cells in human body. Swiss research data show that the probability of breast cancer among residents with high-voltage lines passing around is 7.4 times that of ordinary people. The results of sampling tests conducted by Texas Cancer Medical Foundation on some patients suffering from electromagnetic radiation injury show that the growth rate of cancer cells in workers working near high-voltage lines is 24 times faster than that of ordinary people. 3. It affects the human reproductive system, mainly manifested in the decline of male sperm quality, spontaneous abortion of pregnant women and fetal malformation. It will lead to children's intellectual disability. According to the latest survey, among the 20 million children born every year in China, 350,000 are defective children, of whom 250,000 are mentally retarded. Some experts believe that electromagnetic radiation is also one of the influencing factors. The World Health Organization believes that the electromagnetic radiation from computers, televisions and mobile phones has a negative impact on the fetus. 5, affecting people's cardiovascular system, manifested as palpitations, insomnia, menstrual disorder in some women, bradycardia, decreased cardiac blood volume, irregular sinus heart rate, leukopenia, decreased immune function, etc. If patients with pacemakers are exposed to high electromagnetic radiation, the normal use of pacemakers will be affected. 6. It has a bad influence on people's visual system. Because eyes belong to the sensitive organs of human body to electromagnetic radiation, too high electromagnetic radiation pollution will cause vision loss, cataracts and so on. High-dose electromagnetic radiation will also affect and destroy the original biological current and biological magnetic field of human body, making the original electromagnetic field of human body abnormal. It is worth noting that different people or the same person have different tolerance to electromagnetic radiation at different ages, and the elderly, children and pregnant women are sensitive to electromagnetic radiation. Radiation knowledge The radiation around us is a kind of energy that spreads in the form of waves, particles or photon energy beams. Nuclear radiation refers to the radiation from the nucleus. There are three main types of nuclear radiation affecting human body, namely α, β and γ rays. Alpha rays are a stream of particles composed of helium nuclei. It has a large mass and a lot of charge, but it has a weak ability to penetrate matter and a short range, which can be blocked with an ordinary piece of paper. However, if it enters the human body, it will cause harmful internal irradiation, so it is especially necessary to prevent alpha emitters from entering the human body. Beta rays are composed of high-speed electrons. Compared with alpha rays, it has stronger penetrating power, and can penetrate the stratum corneum of skin and damage living tissues, but it is easily blocked by plexiglass, plastic or aluminum plate. The harm of internal irradiation is also less than that of alpha rays. Gamma rays, like X rays, are composed of invisible photons. It has the strongest penetrating power, and can penetrate a cement wall more than one meter thick. Gamma rays with energy of 1MeV are enough to penetrate the human body. Therefore, γ -ray protection is the most important in external irradiation protection. However, because gamma rays are uncharged photons and cannot directly cause ionization, the harm to human body irradiation is less than that of alpha and beta rays. Radioactivity refers to the inherent characteristics of spontaneous emission of particles or electromagnetic waves by atomic energy. Radionuclides that spontaneously emit particles or electromagnetic waves are called radionuclides. Up to now, 109 elements and about 1800 nuclides have been found. Of the elements 109, 92 are found in nature, and 17 are artificially made. Of the 1800 nuclides, only 270 are stable, and the rest 1500 are unstable and radioactive nuclides. It is not difficult to understand why our environment is full of all kinds of radiation. There are five kinds of people who should pay special attention to electromagnetic radiation pollution: people who live and work near high-voltage lines, substations, radio stations, TV stations, radar stations and electromagnetic wave towers; Personnel who frequently use computers, television electronic instruments, medical equipment and office automation equipment; Workers living in modern electrical automation environment; Patients wearing pacemakers; Pregnant women, children, the elderly and patients living in the above environment. If the electromagnetic radiation pollution in the living environment is relatively high, the public must take corresponding protective measures. Don't put household appliances too concentrated, lest you be exposed to the danger of excessive radiation. Especially some household appliances that are easy to generate electromagnetic waves, such as radios, televisions, computers, refrigerators, etc. , not suitable for centralized display in the bedroom. All kinds of household appliances, office equipment, mobile phones, etc. Try to avoid long-term operation, and try to avoid multiple office and household appliances being activated at the same time. The electromagnetic radiation released at the moment when the mobile phone is turned on is the largest. When using, the distance between the head and the antenna of the mobile phone should be as far as possible, and it is best to use a separate earphone and microphone to answer the phone. Pay attention to the distance between human body and office and household appliances, and keep a safe distance when using various appliances. The farther away from the electrical appliance, the less electromagnetic wave will harm. For example, the distance between color TV and people should be 4 to 5 meters, and the distance between color TV and fluorescent tubes should be 2 to 3 meters. After the microwave oven is turned on, it should be at least 1 meter away, and pregnant women and children should stay away from the microwave oven as far as possible. Conditional units and individuals can be equipped with radiation protection clothing, computer and TV radiation screens, radiation protection curtains, radiation protection glass and other measures to reduce electromagnetic radiation. According to the concept of "more protection and less harm", it is better to believe in it than not to believe in it, so as to prevent any harm.