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Edited on Sat Dec-03-05 06:51 PM by rumpel
found an interesting 2002 analysis report: (sorry if this is old news) Abstract Traces of tritiated water (HTO) were detected at World Trade Center (WTC) ground zero after the 9/11/01 terrorist attack. A method of ultralowbackground liquid scintillation counting was used after distilling HTO from the samples. A water sample from the WTC sewer, collected on 9/13/01, contained 0.174 plus or minus 0.074 (2s) nCi/L of HTO. A split water sample, collected on 9/21/01 from the basement of WTC Building 6, contained 3.53 plus or minus 0.17 and 2.83 plus or minus 0.15 nCi/L, respectively. Several water and vegetation samples were analyzed from areas outside the ground zero, located in Manhattan, Brooklyn, Queens, and Kensico Reservoir. No HTO above the background was found in those samples. All these results are well below the levels of concern to human exposure.
7. Conclusions
34{.3} Ci of tritium were released from the two Boeing 767 on impact with the Twin Towers at the World Trade Center. The limited measurements and modeling are consistent with an instantaneous (catastrophic) creation of HTO from the aircraft emergency signs, deposition of a small fraction of it at ground zero and water-flow controlled removal from the site. The modeling suggests that the contribution from the aircraft would imply the HTO deposition fraction of <3>%, a value which is judged somewhat too high. Therefore, the source term from the airplanes alone is insufficient to explain the measurements and modeling.
Several weapons were present and destroyed at WTC. The modeling is also consistent with the second tritium source from the weapon sights (plus possibly tritium watches) where tritium was slowly released from the debris in the lingering fires, followed by an oxidation and removal with the water flow. Such a limiting case would require a minimum of 115 weapons and a quantitative capturing of tritium. Therefore, such a mechanism alone sufficient, which indicates that the weapon/watch source complemented the airplane source.
full report at
http://repositories.cdlib.org/lbnl/LBNL-50782/
http://en.wikipedia.org/wiki/Tritium
Tritium (symbol T or 3H) is a radioactive isotope of hydrogen. The nucleus of tritium (sometimes called triton) contains one proton and two neutrons, whereas a normal hydrogen nucleus consists of just one proton. Its atomic weight is 3.0160492. It is a gas (T2 or 3H2) at standard temperature and pressure. Tritium combines with oxygen to form a liquid called tritiated water (T2O or partially tritiated THO), somewhat like heavy water (deuterium oxide).
Tritium is radioactive with a half-life of 12.32 years.
snip
All atomic nuclei, being composed of protons and neutrons, repel one another because of their positive charge. However, if the atoms have a high enough temperature and pressure (as is the case in the core of the Sun, for example), then their random motions can overcome such electrical repulsion, and they can come close enough for the strong nuclear force to take effect, fusing them into heavier atoms.
snip
Tritium is used in nuclear weapons to obtain higher yields through nuclear fusion. However, as it decays and is difficult to contain, many nuclear weapons contain lithium instead, since the high neutron fluxes will produce tritium from the lithium when the bomb detonates; see nuclear weapon design.
Like hydrogen, it is difficult to confine tritium; rubber, plastic, and some kinds of steel are all somewhat permeable. This has raised concerns that if tritium is used in quantity, in particular for fusion reactors, it may contribute to radioactive contamination.
on edit adding more from Wikipedia
The emitted electrons from small amounts of Tritium cause phosphors to glow so as to make self-illuminating devices called trasers which are now used in watches and exit signs. It is also used in certain countries to make glowing keychains. In recent years, the same process has been used to make self-illuminating gun sights for firearms. These take the place of Radium, which is chemically poisonous and so has been banned for decades.
"if the atoms have a high enough temperature and pressure then their random motions can overcome such electrical repulsion, and they can come close enough for the strong nuclear force to take effect, fusing them into heavier atoms."
I wonder could the reported relative low level tritium have contributed to the pulverization?
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