On Thursday September 30, 2000, a nuclear accident at a uranium processing plant in Tokyo left two workers in critical condition, and another 310,000 people within a six mile radius were warned to stay in their homes. The radiation level surrounding the plant had jumped thousands of times above normal.
A nuclear reaction occurred when workers added too much uranium to the processing tanks. Plant authorities said there might have been a “critical incident.” Criticality is the point when the nuclear chain reaction becomes self-sustaining, similar to what happens in a nuclear reactor.
The risk of exposure to radiation is often associated with nuclear war and fallout from bombs. But in reality, exposure from a nuclear plant like the one in Japan is more likely.
Those who live near a nuclear plant are more at risk, and should seek advanced preparation for possible leaks or accidents. If applicable, contact the local plant in your area to learn what emergency evacuation procedures they already have in place. Ask them for survival techniques should there be a leak or other accident.
When you are first notified of a possible accident, stay indoors and wait for further instruction. If possible, place as much material between you and the outside; move to the center-most part of your home. If you have a basement or cellar, go there immediately. Contrary to popular myth, radiation fallout does not penetrate everything. Some gamma radiation will reach even those who are in an excellent shelter, but it will the less than the exposure an average American receives from X rays and other radiation exposures that are normal today.
Many homes and buildings built in the 1950's may already have a bomb shelter. Contact your local fire station or other government agency to find out which city buildings have shelters or other underground facilities already built for public use.
A good shelter should have a thickness of earth or other heavy shielding material surrounding it. Gamma rays are rapidly reduced in number by layers of packed earth. For every 3.6 inches of material between you and the gamma rays, the dose of radiation is reduced by half. The denser the substance, the better it serves as a shielding material. For example, the halving-thickness of concrete is only about 2.4 inches, in comparison to compacted dirt which is 3.6 inches.
The human body can usually repair almost all radiation damage if the daily doses are not large.
The first symptoms of radiation sickness are vomiting, headache, dizziness, and a general feeling of illness. This usually starts several hours after exposure, or if it is a larger dose, symptoms will start in 30 minutes, and prove to be fatal.
Even with a shelter, there is a chance of exposure to radiation. There is no medicine to prevent radiation from damaging the human body cells. The thyroid gland is especially susceptible to radiation. Normally, your thyroid absorbs iodine, but it has a set level of iodine that it can store. Certain forms of iodine help your thyroid work right. Most people can get enough iodide from iodized salt or fish in their regular diet.
During exposure to nuclear fallout, radioactive iodine can also be absorbed into the thyroid. Small amounts of radiation in the thyroid will eventually give a large radiation dose to other cells. This can result in loss of the thyroid functions, and even thyroid cancer. The effects of this exposure may not show up for many years.
Eating and drinking fallout contaminated water and food increases the retention of radioactive iodine in the thyroid. Even air that you breathe can add to your indirect exposure.
A way to prevent this absorption of radiation is to fill your thyroid with healthy iodine before radioactive material can get in. A small dose (130 mg) of potassium iodide will provide the thyroid with a daily supply of iodine. If it is taken before exposure to radiation, it will reduce later absorption by the thyroid to only about 1% of what it would have been without the potassium iodide.
Adults and children one year of age or older should take one tablet a day at the direction of state or local public health authorities. Babies under one year of age can take one-half tablet, crushed, once a day. You should take it for 10 days unless otherwise directed. The only people who should not take potassium iodide are those who know they are allergic to iodide.