The Cs-137 contamination of soils in the Netherlands and its consequences for the contamination of crop products.

Abstract

On 2-4 May 1986 the Netherlands was contaminated with radioactive caesium originating from the nuclear accident at Chernobyl. Radiation measurements indicated that the major part of the contamination was associated with rainfall. A sampling and analysis programme confirmed this assumption. To estimate the uptake of Cs-134 and Cs-137 by crops in the future, use was made of the data of the Soil-to-Plant Transfer working group of the IUR (International Union of Radioecologists). The IUR data provide predictor values for the transfer of radionuclides for particular types of crops and soils. Correction factors are presented for the impact of pH, organic matter content and reduction of the availability of radionuclides with time. Uncertainties associated with averaging time and space effects and local differences as well as 95% confidence limits are provided. The predicted levels for edible parts of crops in the Netherlands vary between 0.1 and 10 Bq kg^-1 on a dry weight base. On a fresh weight base these values are even lower. The predicted transfer values are compared with results of uptake experiments at RIVM. It can be concluded that, for the range of conditions tested, there is no indication of severe deviations from the predicted uptake due to local conditions in the Netherlands. Therefore the derived equations for the prediction of the uptake of Cs-137 can be applied. (Abstract retrieved from CAB Abstracts by CABI’s permission)