Lalor, Gerald C.; Onianwa, Percy C.; Vutchkov, Mitko K.
Author Affiliation, Ana.
International Centre for Environment and Nuclear Sciences
Dry-Ashing Preconcentration for Micro-Reactor-Based Neutron Activation Analysis of Food and Plant Samples
International Journal of Environmental and Analytical Chemistry
Date of Publication
The application of preconcentration by dry-ashing to the neutron activation analysis of biological samples using a SLOWPOKE-2 low-power reactor is reported. Samples of selected food crops (banana, callaloo, carrot, mango, and yam) and bioindicator plants (lichen, moss, Tillandsia sp., and tree bark) were analysed both as plant tissue, and as ashed sample. The results are presented for 21 elements. Good agreement between both procedures (<10% relative standard error) was obtained for 13 elements: Al, Ca, Cd, Cr, Fe, K, La, Mg, Mn, Na, Sm, Ti, and V. For Dy, Rb, and Zn the agreement was 10-15%. Relatively poorer agreement (>15-30%) was obtained for As, Br, Cl, and Sb. Dry ashing produced improved analytical results for those samples that were of low ash content. However, the increased background counts observed in ashed samples can sometimes negate the concentration gain, particularly in plants with high ash contents but low levels of certain elements.....