Since 18F- is produced by the 18O(p,n)18F reaction, it is necessary to remove the 18F- ion from it‘s aqueous environment. On the GE Tracerlab MX system, this is performed using a QMA Sep-–Pak column. The 18F- ion is retained on the column whilst the [18O]H2O passes through. –The activated metal ions pass through the columns and are not retained. The 18F is then eluted from the column with an aAcetonitrile solution of Kryptofix and pPotassium cCarbonate (Yu et al., 2006). The long–lived impurities areis removed during synthesis, enabling the final [18F]FDG product to meet the requirements of the pharmacopoeias (BP, 2000; EP, 2002). However, the long–lived impurities are retained in the disposable cassette used on the Tracerlab MX radiochemistry system. Prevcious authors have confirmed the presence of these long-lived impurities in both the the Havar foil and the fluorinated water. –The aim of this study was to measure the levelrs of these long–lived impurities in the disposable cassettes, and thus the levels of radioactive waste generated during synthesis, to determine the most appropriate method of disposal.