Soil to plant transfer of alpha activity in potato plants: impact of phosphate fertilizers

Background: Radionuclides in the phosphate fertilizers belonging to 232Th and 238U and 40 K are the major contributors to the outdoor terrestrial natural radiation. These radionuclides are transferred from fertilizer to food through soil. Materials and methods: Present work deals with the alpha activity in the different parts of the potato (Solanum Tuberosum) plants grown under controlled pots experiment using different amounts of phosphate fertilizers and urea. Alpha activities have been measured by track etch technique using the solid-state nuclear track detectors (LR-115). Results: Translocation factor for the fruit (edible Part) varied from 0.13 (for DAP) to 0.73 (for PF) with an average of 0.40 +/- 0.26 for the plant grown with 20 g of fertilizers. Translocation factors increased with the increase in amount of fertilizers having value 0.51 +/- 0.31 for the plant grown with 50 g of fertilizers. The translocation factor for the lower and the upper part of leaves varied from 0.44 to 0.67 and 0.22 to 0.83 with an average value 0.55 +/- 0.15 and 0.45 +/- 0.23 respectively. The transfer factor (TF's) for the potato plants varied from 1.5 x 10(-2) to 1.03 x 10(-1) for root, from 1.3 x 10(-2) to 1.23 x 10(-1) for stem, from 2.1 x 10(-3) to 4.5 x 10(-2) for fruit and from 5.4 x 10(-3) to 5.8 x 10(-3) for lower part of the leaves after 105 days of the plantation. Conclusions: The results revealed that the alpha activity in the potato plants was higher in case of the plants grown with the use of phosphate fertilizers than with other fertilizers.