a,
Specific Activity
0.33 pCi/ug U
Table
5
Natural Levels of U-238
Estimated Mean
Earth's Crust
Range
Area
Reference
1 pCi/g
3
Sedimentary
o.5 wig
2
igneous
» wife
Rocks
1.5 -3
2
Fresh Water
Lakes and Rivers
LT.
Drinking
uD to 1 pei/t
2.01 pci/1
Calc.
jew York City
?
Ocean Water
1 vei/1
d
Ocean Sediments
1 pci/eg
Human Diet
U5 poi/d
USA, Tri-City
7
Air
Lo7* poi/m?
New York City
7
0.2 - 9 pei/i
2
Z
Body Content
Skeleton
L8c poi
7