[ RadSafe ] Uranium assay; relative sensitivities

[james.g.barnes at att.net]

Folks;

For measurement of mass concentration of uranium (i.e., micrograms of U/Liter), is a radiometric analysis (i.e., pCi/Liter converted to ug/Liter) or a chemical assay measurement (directly measuring for chemical forms of U) more sensitive?

Jim Barnes