Prediction Models for Strontium-90 and Caesium-137 Levels in the Human Food Chain

Abstract

Milk, rye, barley, wheat, oats, potatoes, cabbage, carrots, beef, pork and total diet have been collected all over Denmark since the 1961-62 test series and analysed for 90Sr and 137Cs. A.long with the performance of diet measurements, precipitation, soil and air samples were collected and analysed for 90Sr. The diet levels were related to the fall-out data by a least squares analysis. It was not essential whether concentrations in air (or precipitation) or (deposited activity were used in the "rate" and "lag" terms, although the deposition data tlmded to give the best models. Strontium-90 determinations in human bone and whole-body 13'Cs measurements were performed for the same period as the diet measurements. Quantitative models of the transfer of QOSr and 13'Cs to man were calculated in analogy with the equations used for diet OR bone/diet was calculated from the soil factors in the equations. The prediction models were transformed to exponential equations, which served for the calculation of the dose commitments to the Danish population.

Dating Recent Reservoir Sediments1

“…By associating these peaks with periods of maximum fallout in 1959-1960 and 1963-1964, it is possible to date each profile since no standard DISCUSSION In the examples, peak 137Cs concentration in the sediment profile occurred about 6 to 12 months later than the recorded peak concentration of ls7Cs in atmospheric fallout. A similar time lag has been noted for 137Cs in human food chains (Aarkrog 1971) to indicate a time lag in these biological processes. A time lag for the physical processes of erosion and sediment transport would be expected.…”

Cesium-137 in Humans

“…The level of significance was P < 0.001 and the relationship was 13.58 R Acities = 0.0688 + - (9) with a correlation coefficient of r = 0.977. The level of significance was P < 0.001 and the relationship was 13.58 R Acities = 0.0688 + - (9) with a correlation coefficient of r = 0.977.…”

“…Figure 10 is a plot of the value of the parameter A, obtained from equation (2) as a function of 2, the average 137Cs/K in milk. Also plotted are the expressions describing the relationship of A and 2 for these two groups of data [equations (7) and (9)]. Also plotted are the expressions describing the relationship of A and 2 for these two groups of data [equations (7) and (9)].…”