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Radiocaesium Activity Concentrations in Potatoes in Croatia after the Chernobyl Accident and Dose Assessment

Z. Franic·B. Petrinec·G. Marovic
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Abstract

Systematic investigations of 137Cs and 134Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period (1986-2005) in the Republic of Croatia are summarized. The correlation between 137Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r2=0.88 with P(t) < 0.001 for 18 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of 137Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.8 +/- 1.1 years, the standard deviation being estimated by the Monte Carlo simulations. The initial observed 134Cs:137Cs activity ratio in potatoes has been found to be quite variable, but slightly lesser than theoretically predicted value of 0.5, calculated by applying the known inventory of these radionuclides in the Chernobyl reactor to the equation for the differential radioactive decay. This can be explained by presence of the pre-Chernobyl 137Cs in soil that originated from nuclear fallout. The annual effective doses received by 134Cs and 137Cs intake due to consumption of potatoes estimated for an adult member of Croatian population were found to be very small, as the per caput dose for the entire 1986 - 2005 period was calculated to be about 2.9 mSv, 134Cs accounting approximately for 1/3 of the entire dose. Therefore, after the Chernobyl accident consumption of potatoes was not the critical pathway for human intake of radiocaesium from the environment in Croatia.

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Z. Franic, B. Petrinec, G. Marovic. 2007-01-18. Radiocaesium Activity Concentrations in Potatoes in Croatia after the Chernobyl Accident and Dose Assessment. https://arxiv.org/abs/physics/0701205

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