On March 11, a massive earthquake measuring 9.0 on the Richter scale struck Japan, triggering a tsunami and accidents at several nuclear power plants. The problem of nuclear contamination has caused panic in neighboring countries and regions, and many people in our country have also expressed concern about it. For this reason, we should look at nuclear contamination scientifically and correctly understand the impact of nuclear radiation on the human body. Nuclear contaminated areas scraping northeastern winds will not affect our country Nuclear contamination mainly refers to the damage to the environment caused by the remnants of nuclear material leakage, including nuclear radiation, atomic dust and other pollution caused by itself, as well as the secondary pollution brought about by the pollution of the environment by these substances. Currently, the nuclear pollution caused by the Japanese nuclear power plant refers to the leakage of radioactive substances caused by the accident, which mainly leads to the pollution of the local environment. Air pollution is the main content of environmental pollution, refers to the air contains radioactive substances, such as radioactive aerosols (a kind of tiny particles, dust), which can drift with the wind to contaminate the place where it comes. According to reports, Japan’s nuclear contaminated areas scraping the northeast wind, drifting toward the Pacific Ocean, will not affect our country; on the other hand, China already has a perfect nuclear pollution monitoring system, according to the National Nuclear Safety Administration reported that as of 17 China’s radiation environment level has not been affected by the Japanese nuclear power accident. From the information we know so far, Nikki nuclear power plant explosion is only a general chemical explosion, rather than the explosion of the reactor. Chernobyl nuclear power plant is the explosion of the reactor, so the explosion of the Japanese nuclear power plant, should not cause harm like the Chernobyl nuclear power plant. Small doses of radioactive 131 iodine will not cause damage to humans The main radioactive substances that can be measured in this nuclear contamination to air are radioactive 131 iodine and 137 cesium, which are produced by leaking radioactive substances in nuclear fission. These two radionuclides may cause damage to the human body if they enter the human body at higher doses, with the former affecting thyroid function and the latter affecting hematopoietic function. Since iodine is volatile, the substance in air pollution is mainly 131 iodine… Radioactive radiation requires a certain dose to cause damage to the human body, and small doses of radiation generally do not cause damage to the human body. We grow up in nature and are exposed to small amounts of radiation (naturally) every day. The International Commission on Radiation Protection (ICRP) proposes an effective dose limit of 1 mS for a normal (whole-body) person allowed to be exposed for one year. In exceptional cases, an individual may be exposed to higher effective doses occasionally for 1 year, but not more than 1 mS per year on average over a 5-year period. General diagnostic X-rays of the chest, mouth, and extremities receive an effective dose of about 0.01 mS or 0.02 mS each time. So for small doses of medical radiation (radiology, nuclear medicine) examinations, no damage is caused to the human body. In medicine, we often use radioactive 131 iodine to treat diseases, such as hyperthyroidism and differentiated thyroid cancer clearance, with very good results. Taking iodine tablets is a preventive measure but not for everyone If we face nuclear contamination, we need to face it scientifically and calmly and do radiation protection. External radiation protection (protection from exposure) includes shortening the time of being exposed as much as possible; moving away from the radiation source as much as possible; paying attention to shielding, using lead plates or walls to block or reduce the intensity of exposure. Internal radiation protection (prevention of internal exposure) mainly includes avoiding eating, reducing absorption, increasing excretion, not staying in contaminated areas; removing contamination in a timely manner; not eating contaminated water and food; when entering areas where the air is contaminated with radioactive substances, cover the mouth and nose with handkerchiefs, towels, fabrics, etc. to reduce the absorption of radioactive substances; personnel suspected of being contaminated with radioactivity should be isolated and cleaned and monitored; If the accident is serious, residents need to evacuate the contaminated area. People evacuated from the contaminated area should remove contaminated clothes, shoes, hats, etc. for monitoring and specialized treatment. It was reported that iodine tablets were distributed in a certain area in the disaster area in Japan as a measure to prevent radioactive 131 iodine contamination. The purpose is to seal the thyroid tissue with stable iodine (iodine tablets) to reduce radioactive iodine ingress. This is like a small room that can only accommodate one chair, and after a person sits down, the second person cannot enter, i.e., the stable iodine bursts into the thyroid gland, so that radioactive iodine cannot enter, thus achieving the purpose of prevention. If we are likely to encounter radioactive iodine contamination, we can take stable iodine tablets preventively, but should be taken under medical supervision. Stabilized iodine should be used with caution or not in patients with iodine allergy or certain skin conditions such as acne, eczema, or psoriasis. Experts say a simple conversion is all that is needed to understand. In general, the recommended dosage in case of more serious nuclear contamination is 100 mg of iodine for adults, 50 mg for pregnant women and children between the ages of 3 and 12, and 25 mg for children under the age of 3. Currently, the iodine content of edible iodized salt in China is generally 20 mg – 50 mg per kg. In other words, adults need to consume at least 2,000 grams of iodine salt to reach the recommended standard, “If you eat 4 kg of salt at a time, people will be poisoned long ago!” How to take iodine tablets In order to give full play to the effect of stable iodine on the iodine thyroid blocking effect, it is necessary to take stable iodine tablets before or as soon as possible after being exposed to the light. Even a few hours after the accident, taking iodine tablets can still prevent the thyroid from absorbing 50% of the iodine. To prevent inhalation of radioactive iodine isotopes, a single dose of stabilized iodine is usually sufficient to provide 24-hour continuous protection to the thyroid gland in the event of an incoming cloud of radioactive iodine isotopes. In a long-term continuous release situation, there is a risk of repeated exposure. It is not scientific to use iodine thyroid blockade in combination with other protective measures (such as staying indoors in seclusion, closing doors and windows, etc.) and to apply iodine to the thyroid area to prevent radioactive iodine in most cases. Iodine tablets should not be taken without authorization Experts say that the current monitoring results show that there is no radioactive contamination in the country and that a series of radiation protection measures, including taking iodine tablets, are unnecessary. Since the metabolism of iodine in the body is transient and will be excreted with urine, iodine supplementation in prescribed doses for a short period of time will not be harmful to the general population. However, for some special groups of people, potassium iodide must be taken with caution, such as those with renal insufficiency or thyroid disease, where iodine tablets can cause disease, and pregnant women, where potassium iodide can impair the thyroid function of the fetus. Therefore, potassium iodide must be taken under clear public health guidelines, and should not be taken by the public based on personal subjective assumptions or out of fear. Excessive iodine intake can have side effects on the human body. Excessive iodine intake can disrupt the normal function of the thyroid gland, leading to both hyperthyroidism and hypothyroidism, and exposure of pregnant women to high levels of iodine can lead to neonatal goiter and hypothyroidism. The prevalence of hypothyroidism increases significantly with increasing iodine intake in both pediatric weight and adults. Some studies have shown that iodine supplementation in iodine-deficient areas predisposes to elevated serum thyroid stimulating hormones for a period of time. Most current reports indicate that iodine excess increases the prevalence of autoimmune thyroid disease. In addition, acute iodine toxicity can lead to abdominal cramps, diarrhea with blood in the stool, gastroduodenal ulcers, facial and neck edema, hemolytic anemia, metabolic acidosis, hepatic steatosis, and renal failure.