Multi-element analysis using ICP-MS to determine soil-to-plant and soil-to-mushroom transfer factors

Attempts were made, using inductively coupled plasma-mass spectrometry (ICP-MS) to measure many trace elements in plant, mushroom and soil samples collected in Japan. Sample preparation and analytical conditions were investigated to set up a simple routine procedure for measuring a large range of elements. More than 50 elements were determined for soil samples. For plant and mushroom samples, about 30 elements were determined. Transfer factors (TFs) were estimated from the ratio of 'concentration in plants and mushrooms on dry weight basis' to 'concentration in the surface soils on dry weight basis'. The TFs of lanthanide elements, Th and U were low in all plant and mushroom samples, suggesting transuranium elements had low TFs. The TFs for most elements in crops increased in the following order: polished rice < tubers < root vegetables < leafy vegetables. The low TFs for polished rice might be explained by the low migration of the elements to rice grains from the other parts of the plants. Mushrooms tended to accumulate Cu, Zn, Rb, Cd and Cs. The TFs of Cs for mushrooms were one or two orders higher than those for the plants growing in the same forest. This result is consistent with the high concentrations of radiocesium in mushrooms reported in many countries. (author)