DETERMINATION OF THALLIUM IN URINE BY GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY

Levels of Tl in urine are determined by graphite furnace AAS to assess occupational exposure. Urine samples are digested in nitric acid and made up in 30% hydrochloric acid prior to extraction with diisobutyl ketone (DIBK). Atomization from the tube wall is facilitated by use of reduced Pd modifier. A detection limit of 0.2-mu-g/Tl per liter of urine is achieved. Spot urine samples are also analyzed for creatinine to obtain a 24-hour corrected result.