Luminescence Detection Characteristics for Irradiated Dried Fishes Using PSL-TL System

Photostimulated luminescence (PSL) and thermoluminescence (TL) analyses were conducted for the detection of different irradiated dried fishes. All the non-irradiated samples provided PSL counts of lower than 700 (negative: T1). Clear identification of irradiated sample was only possible for irradiated anchovy with PSL counts >5000; however, the results were unsatisfactory (not positive) for irradiated cod, dried filefish, hairtail, and herring samples. The contaminating silicate minerals were obtained by density separation or acid hydrolysis to perform TL analysis, which resulted in a low intensity of TL glow curve with a maximum peak after 250 o C for the non-irradiated samples that are irrespective of their kinds and methods for the mineral separation. The TL glow curves of high intensity with maximum peak in the temperature range of 150-250 o C were observed for all the irradiated samples. However, better results of TL glow curves and particularly of the TL ratio (TL 1 /TL 2 ) were obtained when the minerals were separated by a acid hydrolysis method.