A Comparison of Analytical Techniques Used for Determination of Fallout Cesium in Sea Water for Oceanographic Purpose

Abstract

Replicate samples of sea water were analyzed for cesium 137, both at Meteorological Research Institute and Scripps Institution of Oceanography for overall comparison of assay. Also analyses done partly on ship were compared with analyses done entirely in the laboratory. Agreement was good in spite entirely different techniques and different primary standards. The independent assays of the two separate laboratories had average difference of only 10%. Replicate of coastal sea water were analyzed for fallout cesium at SIO simultaneously by precipitation with ferrocyanide and also with ammonium molybdophosphate. Relative yields were determined under conditions close to those used for actual oceanographic purposes. Chemical yield resulting from precipitating known amounts of cesium 134 tag in sea water as nickel ferrocyanide was determined and from this, together with the relative yield data, the recovery effectiveness of analyses using ammonium molybdophosphate precipitation was deduced. Recovery of known amounts of radiocesium from sea water by scavenging with ammonium molybdophosphate gave average yields of 94 ± 3% and indicated that the sorbtive efficiency of AMP in sea water was higher than has been reported. Studies of the fundamental behavior of AMP in sea water was initiated.