[ RadSafe ] Quadrillionths of a Gram

Roger Helbig rhelbig at california.com
Mon Sep 11 04:15:15 CDT 2006

Thanks to my good friend Roy Herren's finding the press release from Los Alamos about using a radiometric method to determine the age of ice cores, I searched for other instances of the Femtogram and found where Los Alamos had also used this unit of measure in analyzing sediments from a reservoir -- are any of the rest of you familiar with the Femtogram and the methods used to find this extremely minute amount of uranium or other elements and know more about whether these methods could determine if the substance found in these quantities was in fact depleted uranium or just naturally occurring uranium.  The Federal Court case in NY may in fact hinge on possible misinterpretation of Axel Gerdes analysis of urine samples.

      The concentration of CDFs in city and suburb areas ranges from less than one femtogram (fg) (one quadrillionth of a gram, that is 1/1000,000000000000th of a ...

      Newsbulletin ... the overall amount of plutonium in the sediments -- one quadrillionth of a gram of plutonium per gram of sediment -- is the same as what researchers had ...
            www.lanl.gov/orgs/pa/News/092497.html - 21k - Cached - Similar pages 

Using a sensitive analytical process called thermal ionization mass spectrometry, the researchers were able to take "isotopic fingerprints" of radionuclides found in the sediment and determine how much plutonium was deposited by worldwide fallout from above-ground nuclear weapons tests and how much came from pre-1960s Laboratory operations.


Roger Helbig

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