Harm of x-rays to human body

X-ray examination, as a common means of medical diagnosis, has been widely used in clinic in China. Although most patients know that radiation is harmful to their health, they all think that its harm is minimal. In order to treat diseases, they are used to exposure to X-rays.

But experts point out that X-ray examination is harmful to human body. The more X-rays you take, the greater the risk of cancer. Therefore, as early as 2002, the Ministry of Health issued the Administrative Measures for Health Protection in Radiological Work, which clearly stipulated that medical personnel should provide necessary protection for patients. But what is shocking is that most hospitals are operating illegally at present, and it seems to be a routine to "X-ray patients without any protection", but few people realize the harm. In fact, most patients may not know that the Ministry of Health has this regulation.

Weekend reported that X-ray examination, as a common medical diagnosis method, has been widely used in clinic in China. Although most patients know that radiation is harmful to their health, they all think that its harm is minimal. In order to treat diseases, they are used to exposure to X-rays.

However, this is not the case. Du Guosheng, chief technician of Radiation Health Protection Institute of Beijing CDC, said in an interview that according to the latest research results of the International Commission on Radiation Protection, taking a city with a population of about100000 as an example, about 350 people may be induced by X-rays every year. In Japan, where X-ray and CT examinations are common, 3.2% of new cancer cases are caused by these two examinations every year.

Some experts pointed out that X-ray examination is harmful to human body. The more X-rays exposed, the greater the risk of cancer. Therefore, as early as 2002, the Ministry of Health issued the Management Measures for Health Protection in Radiation Work, which clearly stipulated that medical personnel should take necessary protection for the subjects. But what is shocking is that most hospitals are operating illegally at present, and it seems to be a routine to "X-ray patients without any protection", but few people realize the harm. In fact, most patients may not know that the Ministry of Health has this regulation.

Hospital attitude: how to check patients wearing protective clothing?

The reporter consulted the Measures for the Administration of Health Protection in Radiological Work, in which Article 25 stipulates: "Units engaged in radiological diagnosis and treatment shall formulate quality control implementation plans suitable for the medical treatment projects they are engaged in and abide by the quality control monitoring norms. The protective performance of radiation diagnosis and treatment devices and technical indicators related to radiation quality shall meet the requirements of relevant standards. In the diagnosis and treatment of patients and subjects, the radiation dose should be controlled in strict accordance with the operating procedures, and sensitive organs and tissues near the irradiation site should be shielded and protected; When medical radiation is given to pregnant women and young children, the health impact should be informed in advance. "

However, what the reporter encountered in the hospital was that the radiologist led the patient to the instrument and asked the patient's chest to stand close to the instrument. Then the doctor walked out of the room, closed the thick protective door, and entered the safe room separated by lead glass to operate the instrument, so that the patient could receive X-ray irradiation without any protective equipment.

As a patient, the reporter called the radiology departments of several major hospitals to ask about protective measures. The medical staff in the radiology department of a China hospital paused after receiving the call, as if surprised by the reporter's question. Later, she advised reporters to rest assured: "It is harmless to irradiate X-rays without protective measures, which is common in hospitals. Ordinary patients usually don't wear protective clothing when taking X-rays. Moreover, the current instrument is more advanced than before, and the control of the radiation beam is very accurate, and it will not irradiate the non-inspection parts. Only pregnant women will lick their stomachs. " The medical staff in the radiology department of another big hospital made fun of the reporter's question. They said that "they have never heard of such a regulation" and that "X-rays must be close to the instrument. If you wear protective clothing, how to check it? "

The utilization rate of chest X-ray in China is more than 300 times that in developed countries.

The reporter confirmed through investigation that illegal operation in hospitals is indeed widespread. It seems that most people are quite indifferent to the harm of X-rays.

Then, how did the data put forward by the International Commission on Radiation Protection that a city with a population of10 million has 350 people suffering from cancer, leukemia or other genetic diseases induced by X-rays every year come from? The reporter specially consulted Dr. Yu from the Department of Environment and Radiation Protection of Jiangsu Provincial Center for Disease Control and Prevention.

"In fact, cancer caused by radiation examination is a question of' probability', which has a random effect and may not spread to anyone." Yu explained to the reporter, "The result of 350 people causing cancer is that the population is multiplied by a certain proportion. For individuals, the probability of radiation-induced cancer is random, which may be 0 or 100%. But for a group, the increase in the prevalence rate is affirmative. "

X-ray examination and CT examination are the most common radiation sources that ordinary people are exposed to. This radiation can penetrate cells, destroy DNA and even induce some cancer cells. X-rays will destroy the internal structure of cells and cause irreparable lifelong damage to genetic molecules. Other studies have shown that X-rays can destroy red blood cells and may induce leukemia and other blood diseases.

Although X-ray contains harmful radiation, as a necessary medical means, X-ray examination is still widely used in China. Especially when the patient's superficial symptoms are not enough to diagnose the disease, X-ray and CT examination are needed to help doctors make a definite diagnosis. X-ray examination of fracture is the most common, in addition, abnormal conditions of lung, liver, kidney, spleen and other internal organs can be observed; Bone tumors such as ribs, clavicle and thoracic vertebrae can be found; Mucosal swelling and tumors caused by gastric ulcer and gastroenteritis can also be found. The principle of CT examination and X-ray is basically the same.

Yu told reporters that China had no restrictions on X-ray examination before. In recent years, under the appeal of relevant experts, the state began to pay attention to the problem of medical radiation and issued a series of regulations, but in practice, these regulations have not been well implemented. In contrast, foreign countries should be ahead of China in this respect. Cells in different parts of the human body have different degrees of response to X-rays, among which gonads are the most sensitive. Many countries require shielding and protection of non-examined parts, especially gonads and thyroid gland, in order to minimize radiation damage. If doctors neglect their duties, they are likely to have their radiation licenses revoked. Most developed countries, such as the United States and Japan, have cancelled chest X-ray examination. Among the few countries that use it, the frequency of use in Britain is only 0.2%, while that in China is as high as 6 1.8%!

Du Guosheng, chief technician of Radiation Health Protection Institute of Beijing CDC, mentioned two typical examples when disclosing the hazards of X-rays: In 2004, a hospital in Beijing was warned by the Australian quarantine department for sending unprotected X-rays to Australia. However, when a foreign child went to a domestic hospital for X-ray examination, he jumped out of bed and refused to take pictures. It occurred to him that when taking photos in their country, he always put a lead apron on the patients. The gap between Chinese and foreign concepts about subject protection can be seen.

So how harmful is X-ray examination? Some experts have used orthopedic surgery, which needs X-ray examination most, as an example to calculate the radiation dose of patients during treatment. The times that patients need X-ray examination are: once at the time of diagnosis (if further diagnosis is needed, CT scan is needed), once after operation (patients with joint reduction need to do it again during operation), once a month after operation and once every three months after operation. This is the basic number of exams, ranging from 6 to 4. In the future, it depends on the different rehabilitation conditions of fracture patients, whether the film is clear and needs to be redone, referral from higher and lower hospitals and other factors. Some patients can do 10 times at least.

Take a chest X-ray. When radiation irradiation is carried out in the inspection area, the irradiation rate is about 160 millisieverts (unit for measuring radiation)/hour, which is about 0.045 millisieverts/second. Take chest rib fracture as an example, it takes about 0.5 seconds to take a chest X-ray, so the patient has to bear about 0.023 millisieverts of radiation. According to six X-ray examinations, a patient with rib fracture has to bear a radiation dose of 0. 138 millisieverts.

According to the standards formulated by the International Commission on Radiological Protection, the total radiation risk is 0.0 165/ sievert, that is to say, the probability of cancer will increase by 0.0 1 65 for each dose of radiation received by the human body (1sievert = 1000 millisieverts). Based on this calculation, the risk of a patient with rib fracture will increase by about 3.8/10 million.

For other medical examinations, generally speaking, X-ray examination of limbs requires 0.0 1 msv, abdomen 0.54 msv, pelvis 0.66 msv, lumbar spine10.4 msv, and upper digestive tract 2.55 msv. Based on this calculation, the risk of cancer in healthy people due to physical examination is between one in ten thousand and one in one in one hundred thousand.

Pregnant women and children are high-risk groups of radiation.

Although most hospitals don't take any protective measures when X-rays are applied to ordinary patients, pregnant women are still wary of covering their bellies. Dr. Yu suggested that pregnant women should try to avoid such tests, especially in the first three months of pregnancy. Because this is a critical period for the formation of important fetal organs, X-rays may mutate these undeveloped cells and tissues, and the incidence of fetal congenital malformation will also increase. Another study shows that if the newborn is examined by CT because of head injury, it will have some influence on the later learning ability and logical reasoning ability, but it has no influence on the spatial recognition ability.

In addition to pregnant women, children are also one of the high-risk groups of radiation injury. According to the theory of radiobiology, the radiosensitivity of tissues is directly proportional to the activity of cell division. Children are at the peak of growth and development, with active cell division, which is much more sensitive than adults, and the younger they are, the more sensitive they are. If you receive more X-rays in a short time, the harm will gradually accumulate, causing irreparable damage to body cells, and the probability of inducing diseases such as cancer will greatly increase in the future. Therefore, the national regulations prohibit people under the age of 18 from engaging in occupations related to radiation work.

If the patient is only exposed to X-rays occasionally, the medical staff in the radiology department, as doctors, are more vulnerable to radiation although they have taken some protective measures. The person in charge of the Health Department of the Legal Supervision Department of the Ministry of Health said that the Ministry of Health has monitored hospitals in 15 provinces and cities nationwide, and the records show that medical personnel in all industries have the highest radiation level, and medical radiation is the main source of radiation pollution at present. Due to the long time, high frequency and short distance of exposure to radiation, the radiation intensity of medical personnel is higher than that of traditional nuclear industry personnel.

Short-term exposure of medical staff to high-dose radiation will lead to acute skin burn, necrosis, radiation dermatitis and cataract secondary to lens opacity; Long-term low-dose radiation usually appears after several years or even more than ten years, and leukemia, other tumors and fetal malformation may occur. However, many doctors do not know enough about the harm of medical radiation. Although the hospital also provides corresponding protective measures, in practice, some medical workers will be reluctant to use them because of trouble. Many doctors who do orthopedic surgery and manual reduction under the X-ray machine have stripped the hair off their arms, which shows that radiation has done harm to their bodies.

The standard is useless, and the chest X-ray is abused.

What is the reason for the increase of X-ray radiation hazard ratio? "In fact, the problem is not the lack of standards!" Yu believes that a series of radiation health protection standards issued in China have been in line with international standards, and there is no difference. However, in practice, these standards are often ineffective, and few patients enjoy shielding protection when taking chest radiographs. What's more, sometimes in order to save time, doctors even ask several medical examinees to enter the filming room at the same time, one person takes pictures, and the others wait without any protection. "The hospital may think that patients occasionally come for an X-ray examination, even if there is no protection, the harm is not great. But in fact, medical staff can't ignore the protection of subjects just because they come to the hospital for examination once. "

"We should also strictly grasp the indications of X-ray examination!" Yu pointed out that the radiation dose depends on the radiologist, and whether it is necessary to undergo radiation examination depends entirely on the clinician. In order to obtain higher economic benefits, medical staff in some hospitals abuse X-ray examination. Originally, it was completely unnecessary for the patient to receive X-rays. Therefore, in order to overcharge medical expenses, doctors let patients receive X-rays for no reason. As a medical worker, we should always stand in the patient's position and think for the patient, and try not to use X-ray examination if we can use B-ultrasound examination; If you have to use it, you should also choose X-rays with relatively small radiation dose and avoid using X-ray fluoroscopy.

Examples of obvious abuse of X-ray examination abound in life: every year, children's entrance examination, students' entrance examination, employment examination and unit physical examination are inseparable from X-ray chest radiography. The latest Basic Standard for the Safety of Ionizing Radiation and Radiation Sources (GB18871-2002+0-2002) issued by People's Republic of China (PRC) in 2003 stipulates that "fluoroscopy should be avoided in the screening and general survey of X-ray diagnosis". China's and international radiation health protection standards for children also clearly stipulate that "routine lung examination cannot be used as routine examination items for children and adolescents, such as annual physical examination." However, in China, especially people living in cities with better economic conditions, "chest X-ray" has become a "reserved item" for physical examination, which has long been abandoned abroad.

"Patients should also have a sense of self-protection and refuse unreasonable medical exposure." I am worried that many patients lack awareness of protection. Some patients even become doctors themselves and blindly choose X-rays for themselves without relevant knowledge. There is also the patient's family. There are no patients who need special care, and their families don't have to accompany them to check. There is absolutely no need to be exposed to radiation.

However, people don't have to refuse the necessary X-ray and CT examinations for fear of radiation, and even don't have to dare to enter the radiology department of the hospital. When taking chest radiographs, the exposure rate of X-rays in the examination area is about 160 millisieverts/hour, and it is 80 millisieverts (1 millisieverts = 1000 millisieverts)/hour two meters away from here, which is about 1/2000 of the central point. At this time, the probability of cancer is about one million. The radiation at a distance of 6 meters from the central point is 1.5 microsieverts/hour, which is about one millionth of the central point, and the probability of cancer is even smaller.

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