In daily life, people are often exposed to all kinds of radiation, and different radiation doses have different effects on the human body. Short-term radiation dose is lower than 100 millisieverts, which is harmless to human body. When it is higher than 4000 millisieverts, it is fatal to human body. In radiation medicine and human radiation protection, people use Sifo as an international unit to measure the damage of radiation to biological tissues. Siver is a very large unit, so people usually use millisieverts and microsieverts. 1 millisieverts equals 1000 microsieverts. For people who are not exposed to radiation in their daily work, the normal natural radiation (mainly radon radiation in the air) is 1000 microsieverts-2,000 microsieverts per year. When the intake of short-term radioactive substances is lower than 100 millisieverts, it is harmless to human body. If this number exceeds 100, it will cause harm to human body. 100 mSv-500 mSv, there is no feeling of disease, but the number of white blood cells in blood samples is decreasing. At 1000-2000 millisieverts, radiation will cause slight radiation diseases, such as fatigue, vomiting, loss of appetite, temporary hair loss and erythropenia. At 2000-4000 millisieverts, people's bone marrow and bone density are destroyed, the number of red blood cells and white blood cells is extremely reduced, and symptoms such as internal bleeding and vomiting appear. When it exceeds 4000 millisieverts, it will directly lead to death. In daily life, people fly 10 hour, which is equivalent to receiving 30 microsieverts of radiation. The radiation of Fukushima nuclear power plant is 10 15 microsieverts per hour, which is equivalent to one person receiving 10 x-rays. What harm does radiation do to human body? Radioactive substances release ionic radiation when they decay. This kind of radiation will cause serious damage to the chemical environment inside the human body, and it will break the chemical bonds between various atoms and molecules in human tissues.
The human body will automatically respond to this and try to repair this damage. But sometimes this kind of damage will be very extensive and serious, almost impossible to repair, and there is still the possibility of mistakes in the process of automatic repair. The most sensitive parts of human body to radiation injury are cells in stomach and hematopoietic cells in bone marrow. The harm of radiation to human body depends on your exposure time and radiation intensity. Long-term effects of radiation on human health One of the most serious aspects of the long-term effects of radiation on human health is that it can cause cancer. Generally speaking, once normal cells reach their life span, they will "commit suicide" and die to make way for new cells. When cells lose this "suicide" function, cancer occurs. This cell becomes "immortal" and continues to divide and proliferate, which is out of control.