Isolation of minerals contaminated irradiated food powder for thermoluminescence detection

Thermoluminescence method makes it possible to detect accurately irradiated food. It is necessary to isolate the minerals contaminated in the food prior to thermoluminescence measurement. The procedure for isolation of minerals usually requires large amount of sodium polytungstate which is harmful and expensive. Therefore we tested other safe and inexpensive chemical reagents for pre-isolation such as sodium tungstate (ST), potassium carbonate (K2CO3) and potassium iodide (KI). TL glow ratios and the patterns of glow curves were approximately same between minerals isolated using sodium polytungstate and those pre-isolated using saturated solutions of ST, K2CO3 or KI. Among them, KI was recommended to be the best because of its ease of handling.