Radionuclide Uptake from Soil to Plants: Influence of Soil Classification

Abstract

The entry of trace contaminants, which are present in the terrestrial environment, into human food chains is controlled in the long term by their uptake by plant roots. The radionuclides released into the environment can give rise to human exposure by the transport through the atmosphere, through aquatic systems, or through soil subcompartments. Soil-to-plant factor is one of the important parameters to be used in transfer models for predicting the concentration of radionuclides in crops/plants and for estimating dose impacts to man. Existing databases are limited to experimental values in a restricted number of soil systems and are largely comprised of temperate environment data. In general, transfer factors show a large degree of variation dependent upon several factors such as soil type, species of plants, and other environmental conditions. Soil-to-plant transfers of the radionuclides varied considerably with the times of deposition also. In general, the variations with the deposition times were by a factor of up to 10. This chapter describes a review of published data on the transfer factor (TF) and classification of soils based on TFs.

Transfer from soil to grass and statistical analysis of naturally occurring radionuclides in soil from phosphate mining and processing sites in Maritime Region of Togo

“…This is probably explained by the use of potassium as a crop's fertilizer in the investigated area. However, high values of higher TF for potassium do not pose a risk to human health because 40 K has low contribution to internal dose as 40 K content in the human body is homeostatically controlled (IAEA, 1994;Mollah AS, 2014)). TFs for 226 Ra were found to be less than those of 228 Ra and 40 K in all grass samples in this study.…”

“…TFs for 226 Ra were found to be less than those of 228 Ra and 40 K in all grass samples in this study. This indicates that 226 Ra is less effectively transported from soil to grass than 228 Ra and 40 K. The variation of soil-to-plant transfer factors depends on the soil's properties as the nutrient standard, the exchangeable K content, and the content of moisture in the soil (Frissel et al, 2002;Mollah AS, 2014). For the investigated radionuclides, the literature usually presents the same range of TFs values obtained in the present study except for the 40 K, that are slightly lower than those get in this work.…”

“…An important step to estimate the intake of radionuclides in the human food chain in the form of ingestion in the human organism is known as the soil-plant transfer factor (TF) which is defined as the ratio between the activity concentration of the plant and the activity concentration of the associated soil (Tagami and Uchida 2009;Mollah AS, 2014). TF is a quantity used in investigations to estimate the impact of routine or accidental monitoring releases of radionuclides into the environment for the most important agricultural products such as cereals, tubers, and other plants grown in the same area (Tagami and Uchida 2009;Adjirackor et al, 2014).…”

“…The phosphate well-core is a sample in the solid-state of rock in the form of a cylinder and is taken inside the extraction drilled (IAEA, 1994;Mollah AS, 2014). These extraction and treatment processes produce waste that must be handled with care.…”