2
Specific Activity
800 pCi/g K
Table 3
Natural Levels of K-40
Rstimated Mean
Earth's Crust
Range
Area
Reference
20 poi/g
5
3 wcl/eg
2
Roeks
Tgneou
Ui
Sedimentary
hoped/g
Soil
322 pCi/2
Human Diet
2300 pCi/d
-_
Jcean Water
So - 3 pCli/g
2
1 - 33 pe
2
d,
Calc.
th
Body Content