Nuclear weapons, cessation atmospheric testing

Decrease of Bovine Cesium-137 Concentrations Following the Cessations of Atmospheric Nuclear Weapons Testing... 

This report concerns the changes in concentration of 137Cs in edible tissues of range cattle following the cessation of atmospheric nuclear weapons test series. 

The samples collected after cessation of atmospheric nuclear weapons tests in 1958 and 1963 were examined to ascertain the relative rate of decrease of soft-tissue cesium-137 (Table I). In view of the analysis of variance studies, each tissue and location were considered separately,... 

The half-period for decrease of muscle cesium-137 concentration in NTS animals after the cessation of atmospheric nuclear weapons testing in 1959 appears anomalous (Table I and Figure 2). In addition to being considerably greater (2.3 years) than the other half-periods found, its standard deviation was larger than the value. If one considers only the initial rate of decrease of radiocesium in these muscle samples, one finds a half-period of 0.9 year which is quite consistent with other data. Examination of these data, in comparison with data from liver (Figures 2 and 3), indicates that only muscle decreased its rate of decline in 1960. It should also be noted that the values during 1960 were only about twice the standard error of analysis. Thus, analytical error alone is not an improbable cause of these anomalous values. 

In the long run, the best protection against the buildup of radioactive strontium in the environment is the cessation of nuclear weapons tests conducted in the atmosphere. 

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