Will nuclear plant meltdown in Fukushima, Japan affect other nations?
On March 11, 2011, Japan experienced the worst disaster since WWII. This multifaceted crisis began with a magnitude 9 earthquake off the coast of Sendai. Its eastern coast was then pounded with tsunamis up to three stories high. Days later in southern Japan the Shinmoedake volcano erupted.  As hundreds of thousands were displaced and without power, catastrophic failure affected all three failsafe measures at the nuclear power plant in Fukushima Daiichi, Japan.  Since the great earthquake there, have been hundreds of quakes between 5 and 8 magnitude off the coast of Japan.
Following heroic efforts to bring maters under control in the midst of several explosions, 800 workers at the nuclear plant were evacuated on March 14 as only 50 remained to continue cooling efforts. Radiation levels climbed to 1000 times above normal levels (400 millisieverts) within the plant's No. 3 reactor. In the north-eastern Japanese prefecture of Miyag. In Saitama, near Tokyo, were 40 times normal levels.  Lower levels of radiation detected miles away in the nation's capital, Tokyo, Japan.  Japanese Prime Minister Naoto Kan said Tuesday the risk of further releases of radioactive material remains "very high," as crews struggle to contain an increasingly critical crisis at a severely crippled nuclear plant. 
At a press conference in Tokyo, Masashi Goto, who worked for Toshiba as a reactor researcher and designer, said the mixed oxide fuel used in unit 3 of the Fukushima Daiichi nuclear plant contains plutonium, which is much more toxic than the fuel used in the other reactors. 
For a nation whose debt already exceeds its gross domestic product (GDP) income,  Japan faces years, if not decades of hard work to rebuild. Relief aid is pouring in from other countries.
Who Is At Risk of Contamination?
Fears run high among all inhabitants of Japan. Many people assume that if there is a massive leak of radiation into the atmosphere that the wind will carry the air east over the Pacific to the United States, specifically the west coast (Washington, Oregon, California). Most experts dispute this assumption, saying that any leak that happens, even if massive, will mainly affect the surrounding area by the actual plant at Fukushima. 
Countries immediately to the west include South Korea, North Korea, China, and Russia. Just as shockwaves from the tsunami were felt along the California coast, citizens are concerned over how many countries will be affected in the event of a nuclear fallout. The answer depends on the amount of radiation released and the direction and force of prevailing winds. Russia is measuring higher levels of radiation but not enough to poison its citizens.  With the caveat of unpredictable sources of radiation, models indicate that radioactive nuclear fallout dissipates over time and may be 1/10th as strong 7 hrs later. 
What Levels of Radiation Are Considered Dangerous?
Radiation absorption is measured in a unit called a gray (Gy). Symptoms of radiation sickness usually appear when the entire body receives an absorbed dose of at least 1 Gy. Doses greater than 6 Gy to the whole body are generally untreatable and fatal within two days to two weeks of exposure. 
The sievert has the same units as the gray and is equal to the absorbed dose times the quality factor, which compares the health consequences of that type of radiation with those of x-rays. One hundred millisieverts a year is the lowest level at which any increase in cancer is clearly evident. Above this, the probability of cancer occurrence increases. 
What Are Symptoms of Radiation Exposure?
Initial symptoms of treatable radiation sickness are usually nausea and vomiting. The amount of time between exposure and when these symptoms develop is an indicator of how much radiation a person has absorbed. Later symptoms may include dizziness, fatigue, hair loss, bloody vomit and stools, and infections. High-level radiation exposure can cause acute radiation syndrome, or radiation poisoning, resulting in substantial damage to human body tissues, premature aging and possibly death. Prolonged exposure to low levels is also associated with increased risk of ill health. 
How is Radiation Poisoning Treated?
Of course prevention involves limiting exposure. Workers wear hazmat suits.  Nearby citizens stay indoors with windows closed and air conditioners off. Anyone can purchase "USP Grade" Potassium Iodide at a local chemical supply house, some larger photo supply outlets, or from the Internet and readily mix up their own Potassium Iodide solution that is every bit as effective as the 130 mg tablets. 
Potassium iodide (KI) is a salt of stable (not radioactive) iodine. It can be used as a prophylaxis to block radioactive iodine absorbed into the thyroid gland, protecting it from thyroid cancer. KI cannot protect other parts of the body or reverse damage to the thyroid once it has occurred. It is not a cure-all for all radiation exposure; KI tablets would only protect the thyroid from one type of radiation.  KI works if taken within three to four hours of exposure and should be taken on a daily basis until the threat passes, according to the FDA. Though it's available over the counter, it's smart to consult a doctor before taking it. [13-15] Heavy doses of iodide could be harmful.
Adults older than 40 years should not take KI unless public health or emergency management officials say that contamination with a very large dose of radioactive iodine is expected. Adults older than 40 years have the lowest chance of developing thyroid cancer or thyroid injury after contamination with radioactive iodine. They also have a greater chance of having allergic reactions to KI. 
Prussian blue, a dye used by artists and manufacturers since 1704, can also be used to remove certain radioactive materials from the body. It should only be administered under medical supervision. [13,15]
The tragedy at the Chernobyl nuclear reactor leak in 1986 was dealt with by burrying the reactor in sand and concrete.  When most of the water in the region of radioactive contamination, planting sunflowers on a floating raft capable of reducing the impact of radiation in waters up to 95 percent. The root structure is so dense and strong, it is able to extract heavy metals such as arsenic and lead. 
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