Japanese Plant's Plutonium Containment Vessel 'May' Have Ruptured

[bloom]

The operator of Japan's stricken Fukushima nuclear power plant has admitted there may be damage to the protective containment vessel around the most dangerous fuel rods in the complex -- the plutonium fuel rods in reactor No. 3.

The admission comes after Japan's government announced that workers who suffered burns while trying to cool the crippled No. 3 reactor were exposed to radiation levels 10,000 times higher than expected.

The evidence has raised fears that the crucial containment vessel had, indeed, ruptured in the 9.0 magnitude earthquake of March 11 or subsequent explosions after a tsunami knocked out the cooling systems of the six reactors there.

Officials have previously said that small explosions at the reactor could have damaged it, but the high seepage of radiation could imply worse damage than previously believed.

http://www.rferl.org/content/japan_nuclear_containment_vessel_may_be_ruptured/3536785.html

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Health Effects of Plutonium

Plutonium-239 is a very hazardous carcinogen which can also be used to make nuclear weapons. This combination of properties makes it one of the most dangerous substances. Plutonium-239, while present in only trace quantities in nature, has been made in large quantities in both military and commercial programs in the last 50 years. Other more radioactive carcinogens do exist, like radium-226, but unlike plutonium-239 cannot be used to make nuclear weapons, or are not available in quantity. Highly enriched uranium (HEU) can also be used to make nuclear weapons, but it is roughly one thousand times less radioactive than plutonium-239. The danger is aggravated by the fact that plutonium-239 is relatively difficult to detect once it is outside of secure, well-instrumented facilities, or once it has been incorporated into the body. This is because its gamma ray emissions, which provide the easiest method of detection of radionuclides, are relatively weak.

The main carcinogenic property of plutonium-239 arises from the energetic alpha radiation it emits. Alpha particles, being heavy, transfer their energy to other atoms and molecules within fewer collisions than the far lighter electrons which are the primary means of radiation damage for both gamma and beta radiation.1 Alpha particles travel only a short distance within living tissue, repeatedly bombarding the cells and tissue nearby. This results in far more biological damage for the same amount of energy deposited in living tissue. The relative effectiveness of various kinds of radiation in causing biological damage is known as "relative biological effectiveness" (RBE). This varies according to the type of radiation, its energy, and the organ of the body being irradiated. A simple factor, called quality factor, is used to indicate the relative danger of alpha, beta, gamma and neutron radiation for regulatory purposes. The International Commission on Radiation Protection currently recommends the use of a quality factor of 20 for alpha radiation relative to gamma radiation.2...

http://www.ieer.org/ensec/no-3/puhealth.html

[noneisthenumber]

1. This Just Gets Messier and Messier

Apparently the Japanese Government is now encouraging voluntary evacuation for residents within the 30K zone. Where are the growing numbers of Japanese nuclear refugees going to go? This is seemingly an escalating disaster, with the tragedy building in intensity each day. To me it is both saddening and sickening.

[Zoeisright]

2. In other words, it HAS ruptured.

They wouldn't put that out there unless it had happened. Too much liability otherwise.

[bloom]

3. yes - that's how I interpret it. /nt