max. concentration of radioactive particles in water

winnie_t

Hi,

does anyone know how I can find out the max. concentration of Cs-137 and Sr-90 in water?

Astronuc

One could use a gamma spectrometer to measure the activity of a sample, then compare to a prepared calibration standard. Or one could take a sample, remove the water, measure the mass of the precipitate and the activity, and perhaps used an inductively coupled plasma (ICP) emission test to determine the amount of Cs and/or Sr.

winnie_t

but wouldn't there be a standard max. concentration at which point no more Cs or Sr can dissolve in water? Is this not some data I can find rather to calculate if I don't have to opportunity for an experiment?

nikkkom

Depends on salt. Example

http://en.wikipedia.org/wiki/CsCl
"Solubility in water 1865 g/L"

(you could find it yourself).

You asked "does anyone know how I can find out the max. concentration of Cs-137 and Sr-90 in water?" - IOW, you asked specifically about Cs-137, not caesium in general.

Long before a salt solution with Cs-137 (say CsCl) start approaching saturation, it will be radiating millions of rem/h of gamma.

winnie_t

Thanks nikkkom, I've completely missed out that its the salt dissolving in water rather than the isotope itself.

Astronuc

Well is this about dissolved or particles. Assuming it's of elemental origin, one would probably use the solubility constant for CsOH or Sr(OH)₂. But then is one refering to seawater or freshwater, and there could be other compounds that enhance or hinder solution. Also, Cs and Sr are likely deposited on dust or other solid material.

According to this article, Cs is highly soluble in seawater.
http://www.pnas.org/content/early/20...94109.full.pdf